what are the causes of global warming short essay

Essay on Global Warming – Causes and Solutions

500+ words essay on global warming.

Global Warming is a term almost everyone is familiar with. But, its meaning is still not clear to most of us. So, Global warming refers to the gradual rise in the overall temperature of the atmosphere of the Earth. There are various activities taking place which have been increasing the temperature gradually. Global warming is melting our ice glaciers rapidly. This is extremely harmful to the earth as well as humans. It is quite challenging to control global warming; however, it is not unmanageable. The first step in solving any problem is identifying the cause of the problem. Therefore, we need to first understand the causes of global warming that will help us proceed further in solving it. In this essay on Global Warming, we will see the causes and solutions of Global Warming.

Causes of Global Warming

Global warming has become a grave problem which needs undivided attention. It is not happening because of a single cause but several causes. These causes are both natural as well as manmade. The natural causes include the release of greenhouses gases which are not able to escape from earth, causing the temperature to increase.

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Further, volcanic eruptions are also responsible for global warming. That is to say, these eruptions release tons of carbon dioxide which contributes to global warming. Similarly, methane is also one big issue responsible for global warming.

So, when one of the biggest sources of absorption of carbon dioxide will only disappear, there will be nothing left to regulate the gas. Thus, it will result in global warming. Steps must be taken immediately to stop global warming and make the earth better again.

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Global Warming Solutions

As stated earlier, it might be challenging but it is not entirely impossible. Global warming can be stopped when combined efforts are put in. For that, individuals and governments, both have to take steps towards achieving it. We must begin with the reduction of greenhouse gas.

Furthermore, they need to monitor the consumption of gasoline. Switch to a hybrid car and reduce the release of carbon dioxide. Moreover, citizens can choose public transport or carpool together. Subsequently, recycling must also be encouraged.

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For instance, when you go shopping, carry your own cloth bag. Another step you can take is to limit the use of electricity which will prevent the release of carbon dioxide. On the government’s part, they must regulate industrial waste and ban them from emitting harmful gases in the air. Deforestation must be stopped immediately and planting of trees must be encouraged.

In short, all of us must realize the fact that our earth is not well. It needs to treatment and we can help it heal. The present generation must take up the responsibility of stopping global warming in order to prevent the suffering of future generations. Therefore, every little step, no matter how small carries a lot of weight and is quite significant in stopping global warming.

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FAQs on Global Warming

Q.1 List the causes of Global Warming.

A.1 There are various causes of global warming both natural and manmade. The natural one includes a greenhouse gas, volcanic eruption, methane gas and more. Next up, manmade causes are deforestation, mining, cattle rearing, fossil fuel burning and more.

Q.2 How can one stop Global Warming?

A.2 Global warming can be stopped by a joint effort by the individuals and the government. Deforestation must be banned and trees should be planted more. The use of automobiles must be limited and recycling must be encouraged.

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Essay on Global Warming

• Updated on  
• Apr 27, 2024

Being able to write an essay is an integral part of mastering any language. Essays form an integral part of many academic and scholastic exams like the SAT, and UPSC amongst many others. It is a crucial evaluative part of English proficiency tests as well like IELTS, TOEFL, etc. Major essays are meant to emphasize public issues of concern that can have significant consequences on the world. To understand the concept of Global Warming and its causes and effects, we must first examine the many factors that influence the planet’s temperature and what this implies for the world’s future. Here’s an unbiased look at the essay on Global Warming and other essential related topics.

Short Essay on Global Warming and Climate Change?

Since the industrial and scientific revolutions, Earth’s resources have been gradually depleted. Furthermore, the start of the world’s population’s exponential expansion is particularly hard on the environment. Simply put, as the population’s need for consumption grows, so does the use of natural resources , as well as the waste generated by that consumption.

Climate change has been one of the most significant long-term consequences of this. Climate change is more than just the rise or fall of global temperatures; it also affects rain cycles, wind patterns, cyclone frequencies, sea levels, and other factors. It has an impact on all major life groupings on the planet.

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What is Global Warming?

Global warming is the unusually rapid increase in Earth’s average surface temperature over the past century, primarily due to the greenhouse gases released by people burning fossil fuels . The greenhouse gases consist of methane, nitrous oxide, ozone, carbon dioxide, water vapour, and chlorofluorocarbons. The weather prediction has been becoming more complex with every passing year, with seasons more indistinguishable, and the general temperatures hotter.

The number of hurricanes, cyclones, droughts, floods, etc., has risen steadily since the onset of the 21st century. The supervillain behind all these changes is Global Warming. The name is quite self-explanatory; it means the rise in the temperature of the Earth.

Also Read: What is a Natural Disaster?

What are the Causes of Global Warming?

According to recent studies, many scientists believe the following are the primary four causes of global warming:

• Deforestation 
• Greenhouse emissions
• Carbon emissions per capita

Extreme global warming is causing natural disasters , which can be seen all around us. One of the causes of global warming is the extreme release of greenhouse gases that become trapped on the earth’s surface, causing the temperature to rise. Similarly, volcanoes contribute to global warming by spewing excessive CO2 into the atmosphere.

The increase in population is one of the major causes of Global Warming. This increase in population also leads to increased air pollution . Automobiles emit a lot of CO2, which remains in the atmosphere. This increase in population is also causing deforestation, which contributes to global warming.

The earth’s surface emits energy into the atmosphere in the form of heat, keeping the balance with the incoming energy. Global warming depletes the ozone layer, bringing about the end of the world. There is a clear indication that increased global warming will result in the extinction of all life on Earth’s surface.

Also Read: Land, Soil, Water, Natural Vegetation, and Wildlife Resources

Solutions for Global Warming

Of course, industries and multinational conglomerates emit more carbon than the average citizen. Nonetheless, activism and community effort are the only viable ways to slow the worsening effects of global warming. Furthermore, at the state or government level, world leaders must develop concrete plans and step-by-step programmes to ensure that no further harm is done to the environment in general.

Although we are almost too late to slow the rate of global warming, finding the right solution is critical. Everyone, from individuals to governments, must work together to find a solution to Global Warming. Some of the factors to consider are pollution control, population growth, and the use of natural resources.

One very important contribution you can make is to reduce your use of plastic. Plastic is the primary cause of global warming, and recycling it takes years. Another factor to consider is deforestation, which will aid in the control of global warming. More tree planting should be encouraged to green the environment. Certain rules should also govern industrialization. Building industries in green zones that affect plants and species should be prohibited.

Also Read: Essay on Pollution

Effects of Global Warming

Global warming is a real problem that many people want to disprove to gain political advantage. However, as global citizens, we must ensure that only the truth is presented in the media.

This decade has seen a significant impact from global warming. The two most common phenomena observed are glacier retreat and arctic shrinkage. Glaciers are rapidly melting. These are clear manifestations of climate change.

Another significant effect of global warming is the rise in sea level. Flooding is occurring in low-lying areas as a result of sea-level rise. Many countries have experienced extreme weather conditions. Every year, we have unusually heavy rain, extreme heat and cold, wildfires, and other natural disasters.

Similarly, as global warming continues, marine life is being severely impacted. This is causing the extinction of marine species as well as other problems. Furthermore, changes are expected in coral reefs, which will face extinction in the coming years. These effects will intensify in the coming years, effectively halting species expansion. Furthermore, humans will eventually feel the negative effects of Global Warming.

Also Read: Concept of Sustainable Development

Sample Essays on Global Warming

Here are some sample essays on Global Warming:

Essay on Global Warming Paragraph in 100 – 150 words

Global Warming is caused by the increase of carbon dioxide levels in the earth’s atmosphere and is a result of human activities that have been causing harm to our environment for the past few centuries now. Global Warming is something that can’t be ignored and steps have to be taken to tackle the situation globally. The average temperature is constantly rising by 1.5 degrees Celsius over the last few years.

The best method to prevent future damage to the earth, cutting down more forests should be banned and Afforestation should be encouraged. Start by planting trees near your homes and offices, participate in events, and teach the importance of planting trees. It is impossible to undo the damage but it is possible to stop further harm.

Also Read: Social Forestry

Essay on Global Warming in 250 Words

Over a long period, it is observed that the temperature of the earth is increasing. This affected wildlife, animals, humans, and every living organism on earth. Glaciers have been melting, and many countries have started water shortages, flooding, and erosion and all this is because of global warming. 

No one can be blamed for global warming except for humans. Human activities such as gases released from power plants, transportation, and deforestation have increased gases such as carbon dioxide, CFCs, and other pollutants in the earth’s atmosphere.                                              The main question is how can we control the current situation and build a better world for future generations. It starts with little steps by every individual. 

Start using cloth bags made from sustainable materials for all shopping purposes, instead of using high-watt lights use energy-efficient bulbs, switch off the electricity, don’t waste water, abolish deforestation and encourage planting more trees. Shift the use of energy from petroleum or other fossil fuels to wind and solar energy. Instead of throwing out the old clothes donate them to someone so that it is recycled. 

Donate old books, don’t waste paper.  Above all, spread awareness about global warming. Every little thing a person does towards saving the earth will contribute in big or small amounts. We must learn that 1% effort is better than no effort. Pledge to take care of Mother Nature and speak up about global warming.

Also Read: Types of Water Pollution

Essay on Global Warming in 500 Words

Global warming isn’t a prediction, it is happening! A person denying it or unaware of it is in the most simple terms complicit. Do we have another planet to live on? Unfortunately, we have been bestowed with this one planet only that can sustain life yet over the years we have turned a blind eye to the plight it is in. Global warming is not an abstract concept but a global phenomenon occurring ever so slowly even at this moment. Global Warming is a phenomenon that is occurring every minute resulting in a gradual increase in the Earth’s overall climate. Brought about by greenhouse gases that trap the solar radiation in the atmosphere, global warming can change the entire map of the earth, displacing areas, flooding many countries, and destroying multiple lifeforms. Extreme weather is a direct consequence of global warming but it is not an exhaustive consequence. There are virtually limitless effects of global warming which are all harmful to life on earth. The sea level is increasing by 0.12 inches per year worldwide. This is happening because of the melting of polar ice caps because of global warming. This has increased the frequency of floods in many lowland areas and has caused damage to coral reefs. The Arctic is one of the worst-hit areas affected by global warming. Air quality has been adversely affected and the acidity of the seawater has also increased causing severe damage to marine life forms. Severe natural disasters are brought about by global warming which has had dire effects on life and property. As long as mankind produces greenhouse gases, global warming will continue to accelerate. The consequences are felt at a much smaller scale which will increase to become drastic shortly. The power to save the day lies in the hands of humans, the need is to seize the day. Energy consumption should be reduced on an individual basis. Fuel-efficient cars and other electronics should be encouraged to reduce the wastage of energy sources. This will also improve air quality and reduce the concentration of greenhouse gases in the atmosphere. Global warming is an evil that can only be defeated when fought together. It is better late than never. If we all take steps today, we will have a much brighter future tomorrow. Global warming is the bane of our existence and various policies have come up worldwide to fight it but that is not enough. The actual difference is made when we work at an individual level to fight it. Understanding its import now is crucial before it becomes an irrevocable mistake. Exterminating global warming is of utmost importance and each one of us is as responsible for it as the next.  

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Essay on Global Warming UPSC

Always hear about global warming everywhere, but do we know what it is? The evil of the worst form, global warming is a phenomenon that can affect life more fatally. Global warming refers to the increase in the earth’s temperature as a result of various human activities. The planet is gradually getting hotter and threatening the existence of lifeforms on it. Despite being relentlessly studied and researched, global warming for the majority of the population remains an abstract concept of science. It is this concept that over the years has culminated in making global warming a stark reality and not a concept covered in books. Global warming is not caused by one sole reason that can be curbed. Multifarious factors cause global warming most of which are a part of an individual’s daily existence. Burning of fuels for cooking, in vehicles, and for other conventional uses, a large amount of greenhouse gases like carbon dioxide, and methane amongst many others is produced which accelerates global warming. Rampant deforestation also results in global warming as lesser green cover results in an increased presence of carbon dioxide in the atmosphere which is a greenhouse gas.  Finding a solution to global warming is of immediate importance. Global warming is a phenomenon that has to be fought unitedly. Planting more trees can be the first step that can be taken toward warding off the severe consequences of global warming. Increasing the green cover will result in regulating the carbon cycle. There should be a shift from using nonrenewable energy to renewable energy such as wind or solar energy which causes less pollution and thereby hinder the acceleration of global warming. Reducing energy needs at an individual level and not wasting energy in any form is the most important step to be taken against global warming. The warning bells are tolling to awaken us from the deep slumber of complacency we have slipped into. Humans can fight against nature and it is high time we acknowledged that. With all our scientific progress and technological inventions, fighting off the negative effects of global warming is implausible. We have to remember that we do not inherit the earth from our ancestors but borrow it from our future generations and the responsibility lies on our shoulders to bequeath them a healthy planet for life to exist. 

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Climate Change and Global Warming Essay

Global Warming and Climate Change are two sides of the same coin. Both are interrelated with each other and are two issues of major concern worldwide. Greenhouse gases released such as carbon dioxide, CFCs, and other pollutants in the earth’s atmosphere cause Global Warming which leads to climate change. Black holes have started to form in the ozone layer that protects the earth from harmful ultraviolet rays. 

Human activities have created climate change and global warming. Industrial waste and fumes are the major contributors to global warming. 

Another factor affecting is the burning of fossil fuels, deforestation and also one of the reasons for climate change.  Global warming has resulted in shrinking mountain glaciers in Antarctica, Greenland, and the Arctic and causing climate change. Switching from the use of fossil fuels to energy sources like wind and solar. 

When buying any electronic appliance buy the best quality with energy savings stars. Don’t waste water and encourage rainwater harvesting in your community. 

Also Read: Essay on Air Pollution

Tips to Write an Essay

Writing an effective essay needs skills that few people possess and even fewer know how to implement. While writing an essay can be an assiduous task that can be unnerving at times, some key pointers can be inculcated to draft a successful essay. These involve focusing on the structure of the essay, planning it out well, and emphasizing crucial details.

Mentioned below are some pointers that can help you write better structure and more thoughtful essays that will get across to your readers:

• Prepare an outline for the essay to ensure continuity and relevance and no break in the structure of the essay
• Decide on a thesis statement that will form the basis of your essay. It will be the point of your essay and help readers understand your contention
• Follow the structure of an introduction, a detailed body followed by a conclusion so that the readers can comprehend the essay in a particular manner without any dissonance.
• Make your beginning catchy and include solutions in your conclusion to make the essay insightful and lucrative to read
• Reread before putting it out and add your flair to the essay to make it more personal and thereby unique and intriguing for readers  

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Ans. Both natural and man-made factors contribute to global warming. The natural one also contains methane gas, volcanic eruptions, and greenhouse gases. Deforestation, mining, livestock raising, burning fossil fuels, and other man-made causes are next.

Ans. The government and the general public can work together to stop global warming. Trees must be planted more often, and deforestation must be prohibited. Auto usage needs to be curbed, and recycling needs to be promoted.

Ans. Switching to renewable energy sources , adopting sustainable farming, transportation, and energy methods, and conserving water and other natural resources.

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Digvijay Singh

Having 2+ years of experience in educational content writing, withholding a Bachelor's in Physical Education and Sports Science and a strong interest in writing educational content for students enrolled in domestic and foreign study abroad programmes. I believe in offering a distinct viewpoint to the table, to help students deal with the complexities of both domestic and foreign educational systems. Through engaging storytelling and insightful analysis, I aim to inspire my readers to embark on their educational journeys, whether abroad or at home, and to make the most of every learning opportunity that comes their way.

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This was really a good essay on global warming… There has been used many unic words..and I really liked it!!!Seriously I had been looking for a essay about Global warming just like this…

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I want to learn how to write essay writing so I joined this page.This page is very useful for everyone.

Hi, we are glad that we could help you to write essays. We have a beginner’s guide to write essays ( https://leverageedu.com/blog/essay-writing/ ) and we think this might help you.

It is not good , to have global warming in our earth .So we all have to afforestation program on all the world.

thank you so much

Very educative , helpful and it is really going to strength my English knowledge to structure my essay in future

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Global warming is the increase in 𝓽𝓱𝓮 ᴀᴠᴇʀᴀɢᴇ ᴛᴇᴍᴘᴇʀᴀᴛᴜʀᴇs ᴏғ ᴇᴀʀᴛʜ🌎 ᴀᴛᴍᴏsᴘʜᴇʀᴇ

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Fossil fuels – coal, oil and gas – are by far the largest contributor to global climate change, accounting for over 75 per cent of global greenhouse gas emissions and nearly 90 per cent of all carbon dioxide emissions. As greenhouse gas emissions blanket the Earth, they trap the sun’s heat. This leads to global warming and climate change. The world is now warming faster than at any point in recorded history. Warmer temperatures over time are changing weather patterns and disrupting the usual balance of nature. This poses many risks to human beings and all other forms of life on Earth. 

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ENCYCLOPEDIC ENTRY

Global warming.

The causes, effects, and complexities of global warming are important to understand so that we can fight for the health of our planet.

Earth Science, Climatology

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Ash spews from a coal-fueled power plant in New Johnsonville, Tennessee, United States.

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Global warming is the long-term warming of the planet’s overall temperature. Though this warming trend has been going on for a long time, its pace has significantly increased in the last hundred years due to the burning of fossil fuels . As the human population has increased, so has the volume of fossil fuels burned. Fossil fuels include coal, oil, and natural gas, and burning them causes what is known as the “greenhouse effect” in Earth’s atmosphere.

The greenhouse effect is when the sun’s rays penetrate the atmosphere, but when that heat is reflected off the surface cannot escape back into space. Gases produced by the burning of fossil fuels prevent the heat from leaving the atmosphere. These greenhouse gasses are carbon dioxide , chlorofluorocarbons, water vapor , methane , and nitrous oxide . The excess heat in the atmosphere has caused the average global temperature to rise overtime, otherwise known as global warming.

Global warming has presented another issue called climate change. Sometimes these phrases are used interchangeably, however, they are different. Climate change refers to changes in weather patterns and growing seasons around the world. It also refers to sea level rise caused by the expansion of warmer seas and melting ice sheets and glaciers . Global warming causes climate change, which poses a serious threat to life on Earth in the forms of widespread flooding and extreme weather. Scientists continue to study global warming and its impact on Earth.

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global warming summary

Learn about the causes and effects of global warming.

global warming , Increase in the global average surface temperature resulting from enhancement of the greenhouse effect, primarily by air pollution . In 2007 the UN Intergovernmental Panel on Climate Change forecast that by 2100 global average surface temperatures would increase 3.2–7.2 °F (1.8–4.0 °C), depending on a range of scenarios for greenhouse gas emissions, and stated that it was now 90 percent certain that most of the warming observed over the previous half century could be attributed to greenhouse gas emissions produced by human activities (i.e., industrial processes and transportation). Many scientists predict that such an increase in temperature would cause polar ice caps and mountain glaciers to melt rapidly, significantly raising the levels of coastal waters, and would produce new patterns and extremes of drought and rainfall, seriously disrupting food production in certain regions. Other scientists maintain that such predictions are overstated. The 1992 Earth Summit and the 1997 Kyoto Protocol to the United Nations Framework Convention on Climate Change attempted to address the issue of global warming, but in both cases the efforts were hindered by conflicting national economic agendas and disputes between developed and developing nations over the cost and consequences of reducing emissions of greenhouse gases.

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What Are the Causes of Climate Change?

We can’t fight climate change without understanding what drives it.

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At the root of climate change is the phenomenon known as the greenhouse effect , the term scientists use to describe the way that certain atmospheric gases “trap” heat that would otherwise radiate upward, from the planet’s surface, into outer space. On the one hand, we have the greenhouse effect to thank for the presence of life on earth; without it, our planet would be cold and unlivable.

But beginning in the mid- to late-19th century, human activity began pushing the greenhouse effect to new levels. The result? A planet that’s warmer right now than at any other point in human history, and getting ever warmer. This global warming has, in turn, dramatically altered natural cycles and weather patterns, with impacts that include extreme heat, protracted drought, increased flooding, more intense storms, and rising sea levels. Taken together, these miserable and sometimes deadly effects are what have come to be known as climate change .

Detailing and discussing the human causes of climate change isn’t about shaming people, or trying to make them feel guilty for their choices. It’s about defining the problem so that we can arrive at effective solutions. And we must honestly address its origins—even though it can sometimes be difficult, or even uncomfortable, to do so. Human civilization has made extraordinary productivity leaps, some of which have led to our currently overheated planet. But by harnessing that same ability to innovate and attaching it to a renewed sense of shared responsibility, we can find ways to cool the planet down, fight climate change , and chart a course toward a more just, equitable, and sustainable future.

Here’s a rough breakdown of the factors that are driving climate change.

Natural causes of climate change

Human-driven causes of climate change, transportation, electricity generation, industry & manufacturing, agriculture, oil & gas development, deforestation, our lifestyle choices.

Some amount of climate change can be attributed to natural phenomena. Over the course of Earth’s existence, volcanic eruptions , fluctuations in solar radiation , tectonic shifts , and even small changes in our orbit have all had observable effects on planetary warming and cooling patterns.

But climate records are able to show that today’s global warming—particularly what has occured since the start of the industrial revolution—is happening much, much faster than ever before. According to NASA , “[t]hese natural causes are still in play today, but their influence is too small or they occur too slowly to explain the rapid warming seen in recent decades.” And the records refute the misinformation that natural causes are the main culprits behind climate change, as some in the fossil fuel industry and conservative think tanks would like us to believe.

Chemical manufacturing plants emit fumes along Onondaga Lake in Solvay, New York, in the late-19th century. Over time, industrial development severely polluted the local area.

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Scientists agree that human activity is the primary driver of what we’re seeing now worldwide. (This type of climate change is sometimes referred to as anthropogenic , which is just a way of saying “caused by human beings.”) The unchecked burning of fossil fuels over the past 150 years has drastically increased the presence of atmospheric greenhouse gases, most notably carbon dioxide . At the same time, logging and development have led to the widespread destruction of forests, wetlands, and other carbon sinks —natural resources that store carbon dioxide and prevent it from being released into the atmosphere.

Right now, atmospheric concentrations of greenhouse gases like carbon dioxide, methane , and nitrous oxide are the highest they’ve been in the last 800,000 years . Some greenhouse gases, like hydrochlorofluorocarbons (HFCs) , do not even exist in nature. By continuously pumping these gases into the air, we helped raise the earth’s average temperature by about 1.9 degrees Fahrenheit during the 20th century—which has brought us to our current era of deadly, and increasingly routine, weather extremes. And it’s important to note that while climate change affects everyone in some way, it doesn’t do so equally: All over the world, people of color and those living in economically disadvantaged or politically marginalized communities bear a much larger burden , despite the fact that these communities play a much smaller role in warming the planet.

Our ways of generating power for electricity, heat, and transportation, our built environment and industries, our ways of interacting with the land, and our consumption habits together serve as the primary drivers of climate change. While the percentages of greenhouse gases stemming from each source may fluctuate, the sources themselves remain relatively consistent.

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David Parsons/iStock

The cars, trucks, ships, and planes that we use to transport ourselves and our goods are a major source of global greenhouse gas emissions. (In the United States, they actually constitute the single-largest source.) Burning petroleum-based fuel in combustion engines releases massive amounts of carbon dioxide into the atmosphere. Passenger cars account for 41 percent of those emissions, with the typical passenger vehicle emitting about 4.6 metric tons of carbon dioxide per year. And trucks are by far the worst polluters on the road. They run almost constantly and largely burn diesel fuel, which is why, despite accounting for just 4 percent of U.S. vehicles, trucks emit 23 percent of all greenhouse gas emissions from transportation.

We can get these numbers down, but we need large-scale investments to get more zero-emission vehicles on the road and increase access to reliable public transit .

As of 2021, nearly 60 percent of the electricity used in the United States comes from the burning of coal, natural gas , and other fossil fuels . Because of the electricity sector’s historical investment in these dirty energy sources, it accounts for roughly a quarter of U.S. greenhouse gas emissions, including carbon dioxide, methane, and nitrous oxide.

That history is undergoing a major change, however: As renewable energy sources like wind and solar become cheaper and easier to develop, utilities are turning to them more frequently. The percentage of clean, renewable energy is growing every year—and with that growth comes a corresponding decrease in pollutants.

But while things are moving in the right direction, they’re not moving fast enough. If we’re to keep the earth’s average temperature from rising more than 1.5 degrees Celsius, which scientists say we must do in order to avoid the very worst impacts of climate change, we have to take every available opportunity to speed up the shift from fossil fuels to renewables in the electricity sector.

The factories and facilities that produce our goods are significant sources of greenhouse gases; in 2020, they were responsible for fully 24 percent of U.S. emissions. Most industrial emissions come from the production of a small set of carbon-intensive products, including basic chemicals, iron and steel, cement and concrete, aluminum, glass, and paper. To manufacture the building blocks of our infrastructure and the vast array of products demanded by consumers, producers must burn through massive amounts of energy. In addition, older facilities in need of efficiency upgrades frequently leak these gases, along with other harmful forms of air pollution .

One way to reduce the industrial sector’s carbon footprint is to increase efficiency through improved technology and stronger enforcement of pollution regulations. Another way is to rethink our attitudes toward consumption (particularly when it comes to plastics ), recycling , and reuse —so that we don’t need to be producing so many things in the first place. And, since major infrastructure projects rely heavily on industries like cement manufacturing (responsible for 7 percent of annual global greenhouse gas), policy mandates must leverage the government’s purchasing power to grow markets for cleaner alternatives, and ensure that state and federal agencies procure more sustainably produced materials for these projects. Hastening the switch from fossil fuels to renewables will also go a long way toward cleaning up this energy-intensive sector.

The advent of modern, industrialized agriculture has significantly altered the vital but delicate relationship between soil and the climate—so much so that agriculture accounted for 11 percent of U.S. greenhouse gas emissions in 2020. This sector is especially notorious for giving off large amounts of nitrous oxide and methane, powerful gases that are highly effective at trapping heat. The widespread adoption of chemical fertilizers , combined with certain crop-management practices that prioritize high yields over soil health, means that agriculture accounts for nearly three-quarters of the nitrous oxide found in our atmosphere. Meanwhile, large-scale industrialized livestock production continues to be a significant source of atmospheric methane, which is emitted as a function of the digestive processes of cattle and other ruminants.

Stephen McComber holds a squash harvested from the community garden in Kahnawà:ke Mohawk Territory, a First Nations reserve of the Mohawks of Kahnawà:ke, in Quebec.

Stephanie Foden for NRDC

But farmers and ranchers—especially Indigenous farmers, who have been tending the land according to sustainable principles —are reminding us that there’s more than one way to feed the world. By adopting the philosophies and methods associated with regenerative agriculture , we can slash emissions from this sector while boosting our soil’s capacity for sequestering carbon from the atmosphere, and producing healthier foods.

A decades-old, plugged and abandoned oil well at a cattle ranch in Crane County, Texas, in June 2021, when it was found to be leaking brine water

Matthew Busch/Bloomberg via Getty Images

Oil and gas lead to emissions at every stage of their production and consumption—not only when they’re burned as fuel, but just as soon as we drill a hole in the ground to begin extracting them. Fossil fuel development is a major source of methane, which invariably leaks from oil and gas operations : drilling, fracking , transporting, and refining. And while methane isn’t as prevalent a greenhouse gas as carbon dioxide, it’s many times more potent at trapping heat during the first 20 years of its release into the atmosphere. Even abandoned and inoperative wells—sometimes known as “orphaned” wells —leak methane. More than 3 million of these old, defunct wells are spread across the country and were responsible for emitting more than 280,000 metric tons of methane in 2018.

Unsurprisingly, given how much time we spend inside of them, our buildings—both residential and commercial—emit a lot of greenhouse gases. Heating, cooling, cooking, running appliances, and maintaining other building-wide systems accounted for 13 percent of U.S. emissions overall in 2020. And even worse, some 30 percent of the energy used in U.S. buildings goes to waste, on average.

Every day, great strides are being made in energy efficiency , allowing us to achieve the same (or even better) results with less energy expended. By requiring all new buildings to employ the highest efficiency standards—and by retrofitting existing buildings with the most up-to-date technologies—we’ll reduce emissions in this sector while simultaneously making it easier and cheaper for people in all communities to heat, cool, and power their homes: a top goal of the environmental justice movement.

An aerial view of clearcut sections of boreal forest near Dryden in Northwestern Ontario, Canada, in June 2019

River Jordan for NRDC

Another way we’re injecting more greenhouse gas into the atmosphere is through the clearcutting of the world’s forests and the degradation of its wetlands . Vegetation and soil store carbon by keeping it at ground level or underground. Through logging and other forms of development, we’re cutting down or digging up vegetative biomass and releasing all of its stored carbon into the air. In Canada’s boreal forest alone, clearcutting is responsible for releasing more than 25 million metric tons of carbon dioxide into the atmosphere each year—the emissions equivalent of 5.5 million vehicles.

Government policies that emphasize sustainable practices, combined with shifts in consumer behavior , are needed to offset this dynamic and restore the planet’s carbon sinks .

The Yellow Line Metro train crossing over the Potomac River from Washington, DC, to Virginia on June 24, 2022

Sarah Baker

The decisions we make every day as individuals—which products we purchase, how much electricity we consume, how we get around, what we eat (and what we don’t—food waste makes up 4 percent of total U.S. greenhouse gas emissions)—add up to our single, unique carbon footprints . Put all of them together and you end up with humanity’s collective carbon footprint. The first step in reducing it is for us to acknowledge the uneven distribution of climate change’s causes and effects, and for those who bear the greatest responsibility for global greenhouse gas emissions to slash them without bringing further harm to those who are least responsible .

The big, climate-affecting decisions made by utilities, industries, and governments are shaped, in the end, by us : our needs, our demands, our priorities. Winning the fight against climate change will require us to rethink those needs, ramp up those demands , and reset those priorities. Short-term thinking of the sort that enriches corporations must give way to long-term planning that strengthens communities and secures the health and safety of all people. And our definition of climate advocacy must go beyond slogans and move, swiftly, into the realm of collective action—fueled by righteous anger, perhaps, but guided by faith in science and in our ability to change the world for the better.

If our activity has brought us to this dangerous point in human history, breaking old patterns can help us find a way out.

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• Global Warming Essay

Essay on Global Warming

The last few decades have been monumental when it comes to technological development. Humans have developed systems and machines that make our lives easier. Especially during the early modern period from the early 16th century to as far as the late 18the century, also commonly referred to as “The Scientific Revolution” or “The Enlightenment”, modern technology leapt ahead in development in such a short time frame compared to all of history.

However, with the development of society, there has been a severe detriment to the quality of Earth’s environment. One of the most massive threats to the condition of the planet is climate change. Inadequate research and reckless misuse of natural resources are some of the core reasons for the deteriorating condition of the planet.

To understand the concept of Global Warming and its causes and effects, we need to take an in-depth look into many factors that affect the temperature of the planet and what that means for the future of the world. Here is an objective look at the topic of Global Warming and other important related topics.

What is Climate Change?

Ever since the industrial and scientific revolution, Earth is slowly being used up for its resources. Moreover, the onset of the exponential increase in the world’s population is also very taxing on the environment. 

Simply put, as the need for consumption of the population increases, both the utilisation of natural resources and the waste generated from the use of said resources have also increased massively. 

One of the main results of this over the many years has become climate change. Climate change is not just the rise or fall of temperature of different areas of the world; it is also a change in the rain cycles, wind patterns, cyclone frequencies, sea levels, etc. It affects all major life groups on the planet in some way or the other.  

What is Global Warming?

Global Warming is often considered an effect of Climate change. Global Warming is the rapid increase in the temperature of the Earth’s environment that is causing many life-threatening issues to arise.

Global Warming is a dangerous effect on our environment that we are facing these days. Rapid industrialization, increase in the population growth and pollution are causing a rise in Global Warming. Global Warming refers to the increase in the average temperature of the earth's surface during the last century. One of the reasons why Global Warming is dangerous is because it disturbs the overall ecology of the planet. This results in floods, famine, cyclones and other issues. There are many causes and results of this warming and is a danger for the existence of life on earth.

The sign of Global Warming is already visible with many natural phenomena happening around globally, affecting each living species.

Here is some data that can help to give a more precise understanding of the reality of Global Warming in the last few years:

On average, the world’s temperature is about 1.5°C higher than during the start of the industrial revolution in the late 1700s. That may not seem a lot to you, but that is an average estimate. This number is only increasing. Many parts of the world face far more severe changes in temperature that affect the planet’s overall health.

In 1950, the world’s CO 2 emissions were at 6 billion tonnes which had quadrupled in volume until 1990, just 40 years later to 22 billion tonnes. Not only that, unchecked CO 2 emissions today have reached a whopping 35 billion tonnes.

The most evident causes of Global Warming are industrialization, urbanization, deforestation, and sophisticated human activities. These human activities have led to an increase in the emission of Greenhouse Gases, including CO₂, Nitrous Oxide, Methane, and others.

Causes of Global Warming

A variety of reasons causes Global Warming. Some of which can be controlled personally by individuals but others are only expected to be solved by communities and the world leaders and activists at the global level.

Many scientists believe the main four reasons for Global Warming, according to recent studies, are:

Greenhouse gases

Deforestation

Per capita carbon emissions

Global Warming is certainly an alarming situation, which is causing a significant impact on life existence. Extreme Global Warming is resulting in natural calamities, which is quite evident happening around. One of the reasons behind Global Warming is the extreme release of greenhouse gases stuck on the earth surface, resulting in the temperature increase.

Similarly, volcanoes are also leading to Global Warming because they spew too much CO₂ in the air. One of the significant causes behind Global Warming is the increase in the population. This increase in the population also results in air pollution. Automobiles release a lot of CO₂, which remains stuck in the earth.

This increase in the population is also leading to deforestation, which further results in Global Warming. More and more trees are being cut, increasing the concentration of CO₂.

The greenhouse is the natural process where the sunlight passes through the area, thus warming the earth's surface. The earth surface releases energy in the form of heat in the atmosphere maintaining the balance with the incoming energy. Global Warming depletes the ozone layer leading to the doom's day.

There is a clear indication that the increase in Global Warming will lead to the complete extinction of life from the earth surface.

Solution for Global Warming

Global Warming can not be blamed on individuals; however, it can be tackled and maintained from worsening starting at the individual level. Of course, industries and multinational conglomerates have higher carbon emissions levels than an average citizen. Still, activism and community effort are the only feasible ways to control the worsening state of Global Warming.

Additionally, at the state or government level, world leaders need to create concrete plans and step programmes to ensure that no further harm is being caused to the environment in general. 

Although we are almost late in slowing down the Global Warming rate, it is crucial to find the right solution. From individuals to governments, everyone has to work upon a solution for Global Warming. Controlling pollution, population and use of natural resources are some of the factors to consider. Switching over to the electric and hybrid car is the best way to bring down the carbon dioxide.

As a citizen, it is best to switch over to the hybrid car and to use public transport. This will reduce pollution and congestion. Another significant contribution you can make is to minimize the use of plastic. Plastic is the primary cause of Global Warming taking years to recycle.

Deforestation is another thing to consider that will help in controlling Global Warming. Planting of more trees should be encouraged to make the environment go green.

Industrialization should be under certain norms. The building of industries should be banned in green zones affecting plants and species. Hefty penalties should be levied on such sectors contributing towards Global Warming.

Effects of Global Warming

Global Warming is a real problem that many want to prove as a hoax for their political benefit. However, as aware citizens of the world, we must make sure only the truth is presented in the media.

Various parts of the environment, both flora and fauna, are directly adversely affected by the damages caused by Global Warming. Wildlife being in danger is ultimately a serious threat to the survival of humanity as we know it and its future.

The effect of Global Warming is widely seen in this decade. Glacier retreat and arctic shrinkage are the two common phenomena seen. Glaciers are melting in a fast way. These are pure examples of climate change.

Rise in sea level is another significant effect of Global Warming. This sea-level rise is leading to floods in low-lying areas. Extreme weather conditions are witnessed in many countries. Unseasonal rainfall, extreme heat and cold, wildfires and others are common every year. The number of these cases is increasing. This will indeed imbalance the ecosystem bringing the result of the extinction of species.

Similarly, marine life is also widely getting affected due to the increase in Global Warming. This is resulting in the death of marine species and other issues. Moreover, changes are expected in coral reefs, which are going to face the end in coming years.

These effects will take a steep rise in coming years, bringing the expansion of species to a halt. Moreover, humans too will witness the negative impact of Global Warming in the end.

FAQs on Global Warming Essay

1. What Global Warming will Cause?

Global warming will have a massive impact on our earth in the end. Flood, extreme weather conditions, famine, wildfire and many more will be the result. There will be hotter days, which will also increase the wildfire and famine. In the past years, many meteorological bureaus have added purple and magenta to the forecast.

Another impact of global warming will be rising sea levels. Increased ocean temperatures will lead to the melting of glaciers and ice caps. Increase in the sea level will lead to floods in many low-lying areas.

The overall ecosystem of nature will be an imbalance. This will affect nature in the long-term.

2. Why Does Global Warming Happen?

There are many reasons for the cause of global warming. There are certain gases in the atmosphere called greenhouse gases. The energy then radiates from the surface; the greenhouse gases trap longwave radiation. We humans have added to the atmospheric blanket of greenhouse affecting the living species. Warming of air, oceans, and land is how global warming happens.

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Global Warming: Causes And Consequences

The familiar photo of the Earth spinning in the blackness of space that was taken 50 years ago by William Anders, an astronaut on the Apollo 8 lunar mission, starkly illustrated our isolation on this planet. Now we face a crisis as the climate and environmental conditions that support life as we know it become ever more fragile owing to CO 2 -induced global warming. The evidence suggests there is significant risk that areas of the Earth in tropical zones may become uninhabitable and that significant food chains will collapse in this century. 

Spaceship Earth

The familiar photo of the Earth spinning in the blackness of space that was taken 50 years ago by William Anders, an astronaut on the Apollo 8 lunar mission, starkly illustrated our isolation on this planet. Now we face a crisis as the climate and environmental conditions that support life as we know it become ever more fragile owing to CO 2 -induced global warming. The evidence suggests there is significant risk that areas of the Earth in tropical zones may become uninhabitable and that significant food chains will collapse in this century. We agree with those who say that the highest human priority now is to greatly reduce human societies’ reliance on CO 2 -producing oil and coal. However, even the most optimistic projections of reduced CO 2 production and resulting reductions in climatic warming suggest that future generations will face daunting problems. Fortunately, this growing disruption is occurring at a time of unprecedented breakthroughs in science and technology. Although there are many things that can be done to ameliorate individual events, the worldwide effort is uncoordinated and there is widespread resistance from vested economic and political interest groups. Here, we first survey the consequences of the rapid rise in CO 2 emissions and then consider the possibility that new genetic technologies can help mitigate some of the biological consequences of global changes in climate patterns.

Life on Earth has evolved in an interconnected ecology determined by weather patterns, movements of global tectonic plates, and the dynamic surface chemistry of oceans and land. The creatures on Earth—all the humans, animals, plants, bacteria, fungi, and viruses—are dependent on each another as well as on this enveloping ecosystem. Since the Earth is an integrated system, significant changes in any internal component or in external influences induce movement toward a new equilibrium. Throughout the history of the Earth there have been long periods of cooling leading to growth of massive continental ice sheets, interspersed with warm intervals. While the causes of these ice ages are not fully understood, the principal contributing factors have been identified. The composition of the atmosphere, particularly the concentration of carbon dioxide and methane, is important. Also changes in the Earth’s orbit around the sun, changes in the tilt in the Earth’s axis, impacts of large meteorites, and eruptions of super volcanoes. The latter two phenomena can both put massive amounts of particulate matter and carbon dioxide into the atmosphere.

In two instances, biological phenomena have disrupted the composition of the atmosphere with global consequences. One was the Great Oxidation Event or the Oxidation Catastrophe, around 2.45 billion years ago. This occurred after a bacterial species, an ancestor of contemporary cyanobacteria, evolved the ability to produce oxygen as a byproduct of photosynthesis. This event had extraordinary consequences for ocean chemistry and eventually for the slow accumulation of atmospheric oxygen to contemporary levels over an interval of several million years. The newly oxygenated atmosphere was toxic to virtually all the anaerobic organisms that then populated the earth. These organisms died and were replaced by creatures that could thrive in the new oxygenated atmosphere. 1 Now, the current human-induced increase in atmospheric CO 2 is the second biological disruption of atmospheric composition that is producing global warming with credible predictions of ever more dire consequences in coming decades. Consequences we are already seeing include:

Accelerating rise in global sea level owing to irreversible melting of glacial ice in the European Alps, melting of arctic ice, and of greatest concern, melting of the land ice sheets in Greenland and Antarctica.

Large changes in climate patterns that have led to cataclysmic wild fires encouraged by the hottest summers on record and extreme floods stemming from new and disruptive storm patterns.

Acidification and warming of the oceans leading to decimation of coral reefs and other changes that are disrupting the marine food chain.

The global redistribution of bacterial, fungal, and viral pathogens and their vectors out of the tropics and into temperate zones and the emergence of previously unknown pathogens.

As the Earth’s climate continues to warm owing to increasing levels of atmospheric CO 2 the mean sea level will rise. 2 The mean sea level has risen about 8 inches since the late 1800s, and projections suggest an accelerating rise of between 2 and 6 feet by 2100. 3 The predominant contributor to the future sea level increase will be melting of the enormous land-based ice sheets and glaciers on Antarctica and Greenland. The amount of the rise will be strongly dependent on mankind’s success in limiting future CO 2 emissions. However, even the lowest estimates portend devastating consequences: 4 loss of arable land owing to flooding and salt water intrusion (e.g., Vietnam, Bangladesh, California’s Salinas valley 5 ); major population displacements (100 million people will be displaced by a three-foot rise); many coastal areas may have to be abandoned (e.g., South Florida and Miami 6 ).

We are already experiencing changes in global weather patterns. Regions accustomed to temperate temperatures and predictable periods of rainfall are seeing prolonged drought and periods of extreme high temperature, while other regions are experiencing excess rain and snowfall along with lower ambient temperatures. In parts of Australia, drought and peak summer temperatures nearing 116 o F are causing vast wildfires. Simultaneously, U.S. states around the Great Lakes have experienced winter temperatures of -34 o C (-29.2 o F) that are significantly colder than temperatures in the Arctic. This skewing of ambient temperatures in North America is due to changes in the jet stream that have allowed polar air from the Arctic to flow into zones normally buffered against temperature extremes. Global warming contributes to these unusual weather patterns through its influence on the polar vortex, a wide expanse of swirling cold air near the pole. 7 Over a surprisingly short time, the average temperature rise at the north polar region has been higher than in some more southerly areas. While average temperatures across the globe have now increased to 1.2 o C above preindustrial revolution levels, the poles have seen an average increase of 3 o C. During March 2018, temperatures in Siberia were 15 o C (59 o F) above historical averages, and Greenland experienced a period of 61 hours above freezing (three times longer than any previous year), while temperatures were unusually low in Europe. These disruptions in global weather patterns have caused long-term drought conditions in some regions and unprecedented floods in others, leading to loss of arable land and precipitous reductions in agricultural production. Those who deny climate change often point to periods of extreme cold in unexpected regions as evidence supporting their views, without understanding that the large-scale changes in weather patterns are a central consequence of global warming. When the oceans warm, global weather patterns are disrupted in many areas in unexpected ways.

It is important to recognize that these global events are interconnected. For example, consider the consequences of sustained rainfall on degraded farmland: Increased rainfall leads to soil erosion, that in turn results in the release of phosphorous from fertilized soil into rivers and the oceans. That release, in turn can stimulate algal blooms and red tides, further reducing the ocean oxygen levels that are already lowered by warming waters. These phenomena add to the impacts of warming and acidification on food chains in the ocean.

What will be the impact of global warming on our land-based food supply and our ability to maintain the animals and plants we depend on? Warming is already slowing yield gains in most wheat-growing locations, and global wheat production is expected to fall by 6% for each 1°C of further temperature increase while becoming more variable. 8 Global production of corn is similarly at risk. 9 Global warming will alter world food production patterns, with crop productivity reduced in low latitudes and tropical regions but increased somewhat in high latitude regions. This will lead to trade changes with expanded sales of food products from the mid-to-high latitudes to lower latitude regions. 10

Extinction of species owing to expanding human activities around the globe has been accelerating over the last two centuries. Now the onset of changes in the climate is accelerating the rate of extinctions. Disruptions of habitats, loss of food sources, and the spread of infectious diseases are happening at a rate that cannot be accommodated by evolutionary adaptation. The number of species that have gone extinct in the last century alone would have taken between 800 and 1000 years to disappear in previous mass extinctions. 11 During one of these extinctions, the Permian-Triassic extinction 250 million years ago, 12,13 the earth lost 96% of all marine species, 100% of the coral reefs, and 70% of terrestrial vertebrates. In that event, the accumulation of carbon dioxide in the atmosphere led to ocean warming and to ocean acidification that together played a key role in the global loss of life. Recovery from that extinction event took more than 10 million years.

Currently, we are experiencing a 6 th mass extinction, 11 and we are approaching up to 100x higher rates of extinction than the background rate. There are two critical differences now. First, the current rate of change to the earth’s ecosystem is occurring in a few decades rather than over thousands of years as in the previous five extinction periods. Second, the events underlying the current cataclysm are man-made. Metaphorically, we are riding a runaway climate train with no one at the controls.

Effects on the Oceans

In the past there have been few established populations of invasive species identified in the high northern latitudes, that is, the northern coasts of Canada or Russia. With the continuing loss of Arctic sea ice, this situation will change. There has been rapid growth of shipping traffic along the northern coast of Russia in recent years, a large cruise ship went through the Northwest Passage in 2016, and now multiple arctic cruises are advertised each year. We can expect continuing expansion in arctic shipping activities, mineral/energy exploration, fishing, and tourism in future years. These new northern transport routes offer shorter and less expensive connections between northern hemisphere ports, so the shipping traffic will inevitably grow as more ice melts and warmer weather seasons get longer. Introduction of invasive species into these Arctic regions will follow rapidly. This will bring new challenges to the native inhabitants—humans, wildlife, and plants—of these northern ocean and terrestrial habitats. There will be greater competition for food sources and introduction of new infectious diseases. This sequence of events has occurred innumerable times before when alien populations expanded into new regions. 14

Currently, the oceans absorb 93% of the heat trapped by greenhouse gases in the atmosphere, thus slowing warming of land masses. But the resulting rapid warming of the oceans directly impacts marine life and related food chains. Consider, for example, the coral reefs along over 93,000 miles of coastline rimming the oceans—one of the largest ecosystems on the planet.

A thriving coral reef is comprised of groups of millions of identical tiny polyps a few millimeters wide and a few centimeters long, each with a calcite skeleton. Millions of these tiny stony skeletons accumulate over generations to form the large hard coral reefs found along tropical shorelines. Many of the coral species obtain most of their nutrients from photosynthetic algae plants called zooxanthellae . When the sea around them warms excessively, the polyps expel the zooxanthellae and the coral becomes completely white—a condition called coral bleaching. Corals can survive bleaching events and restore the zooxanthellae , if conditions normalize quickly enough. But the bleaching events are highly stressful, and the corals will die if occurrence of bleaching events persists. When this happens, only the dead coral skeletons—which can be immense—are left.

The Great Barrier Reef, 500 feet thick at some points, extends discontinuously for over 1500 miles off the coast of eastern Australia. By 2018, half of the Great Barrier Reef had died from heat stress. Similar damage is occurring in the Caribbean and the rest of the world’s tropical shorelines. 15,16

Loss of the ocean reef ecosystems could substantially compromise the Earths ability to sustain the health and well-being of its inhabitants. Fish populations in the coral reefs are the source of food for hundreds of millions of people. Loss of the reefs disrupts the marine food chain which causes loss of local food supplies, stressed populations, and conflicts over fishing rights.

There is now a global sense of urgency to develop methods to restore and maintain the health of the reefs considering their increasing destruction. Corals can evolve to survive in changed conditions—warmer, more acidic, etc. However, the rate of natural adaptation is too slow relative to the current rate of changes in their ocean environment, so there is widespread devastation of established reefs. This has led to efforts to accelerate the rate of adaptation. In some stressed reefs, small coral colonies are found that have successfully adapted to the local changes in temperature and increased acidity. Reef preservationists have shown that corals harvested from these colonies can be nurtured in coral “farms” and then used to seed new growth in damaged areas. Scientists are also experimenting with selective breeding to develop coral strains better adapted to changed conditions. 17–19

In Indonesia another attempt at coral reef remediation involves attaching optimized coral polyps to metal rods planted within the compromised reefs. The application of a mild electric shock causes minerals in the water to precipitate and adhere to the metal structures, thus stimulating calcification with the goal of creating the more native ‘cement’ of a reef’s exoskeleton, referred to as ‘Biorock.’ 20 The resulting limestone surface increases the growth of the corals under conditions that would normally lead to their death. All these schemes are highly promising, but there are daunting cost and logistical barriers to scaling restoration efforts to address the vast areas of lost reefs.

Global Warming Is Changing the Distribution of Animal and Plant Pathogens

The last century has seen radical changes in the pattern, volume, and speed of transport of people and cargo between widely separated regions on the planet. One consequence has been the increase in direct long-distance human transport of dangerous infectious diseases by person to person transmission. Surveillance of travelers at entry points, coupled with identification, treatment, and when necessary, quarantine of the infected persons and their contacts, has been the response strategy. But diseases that are carried by intermediate vectors, for example, mosquitoes or ticks, present a different and more complex challenge. Any such vector is adapted to thrive in some environmental niche—characterized by a temperature and rainfall range, urban or rural, indoor or outdoor, etc. When a region’s climate warms, it may become hospitable to new vectors, which will then inevitably arrive either by expansion from adjacent territories or as accidental hitchhikers in freight shipments or transport vehicles.

For example, in a remarkably short time, human viruses like Zika, Dengue, Chikungunya, Yellow Fever, and West Nile have spread into regions of the Caribbean, Latin America, and the United States that until recently had ambient temperatures below that required to support their transmission. In addition, fungal infections of food plants, like the blights infecting Cavendish bananas and cocoa trees, have become a global problem. The rapid spread of global disease caused by changes in atmospheric temperature, ocean temperature, erratic and drenching rains, and floods in one geographic location accompanied by droughts in another location is being facilitated by migration of the vectors, such as mosquitoes, ticks, bats, and rats, that carry the pathogens. Insect vectors are exquisitely sensitive to changes in temperature, and warmer temperatures increase their breeding season and life span. Zika, Dengue, Chikungunya, and Yellow Fever viruses soon follow arrival of the common Aedes aegypti mosquito and are then transmitted among humans by the female mosquito. Other mosquito species transmit West Nile virus, the malaria parasite, and the parasitic nematode worm that causes the human disfiguring disease lymphatic filariasis (elephantiasis).

Ticks are another rapidly spreading vector. Although most tick species do not harbor pathogens harmful to humans, Lyme disease is caused by a tick-borne bacterial pathogen, Borrelia burgdorferi . Until recently, ticks were inhibited over much of North America by cold winters, but with increasing average temperatures and milder winters they are becoming established further north. Lyme disease is now endemic in Canada, so the government has recently established tick surveillance networks.

The vector-borne bacterial pathogen Candidatus Liberibacter that causes citrus greening disease is a serious agricultural threat. Liberibacter are transferred to citrus trees by an insect vector, the Asian citrus psyllid or jumping plant lice. The disease causes the decline and death of citrus trees by blocking the flow of nutrients and sugars from the leaves to the roots. Once infected, the tree is doomed. Liberibacter have recently migrated along with the citrus psyllid vector to warming temperate climate zones worldwide, including ten U.S. states. 21 The resulting Citrus Greening infections have devastated the Florida citrus industry and destroyed citrus groves in Asia, Brazil, and the Dominican Republic. In the United States, the damage has been less in states further north than Florida, probably because of their cooler temperatures, but as the climate warms, the citrus greening infections will likely continue moving northward.

Owing to the huge financial impact of citrus greening, there are multiple biology-based efforts underway to disrupt the infection pathway either by eliminating the psyllid vector, by killing the bacterial Liberibacter pathogen, or by developing an infection resistant citrus tree variety. 22 Insect warfare has also been tried by introduction of a wasp that preys specifically on the Asian citrus psyllid. This strategy works, but it only reduces, rather than eliminating, the citrus psyllid population. 23

Each biological approach tried so far has its pros and cons. Insecticides can kill the citrus psyllid, but they may also threaten beneficial insects. Antibiotics may kill the Liberibacter, but their use can also increase bacterial antibiotic resistance and thus loss of antibiotic effectiveness for treating human diseases. This story of the challenges of containing the spread of the citrus greening disease is representative of similar challenges encountered in trying to deal with a myriad of newly encroaching diseases, some carried by other insect vectors. Are there better solutions on the horizon? It may be that recent advances in genetic technology will lead to more effective approaches.

Can New Genetic Technologies Reduce Global Warming Consequences?

Along with the increasing threat of climate change to human health and agriculture, we are experiencing a revolution in genetic engineering technology. Perhaps this will lead to new methods for effective surveillance and for mitigation of the redistribution of vectors that transmit disease.

The new CRISPR Cas9 technology lets us change specific genes in an insect or animal vector, thus making it either unable to serve as a reservoir for a given pathogen (known as a population modification drive) or eliminating the ability of the vector to propagate (known as a suppression drive). A suppression drive targets the reproductive capacity of the insect vector and can lead to a population crash, potentially wiping out a species. A population modification drive does not affect the reproduction capability of the insect, but it prevents the vector from harboring the pathogen or it prevents transmitting the pathogen to the human host. With these technologies, the genetic makeup of a few individuals in a targeted vector species is changed in such a manner that once these individuals are released into the wild, the change spreads rapidly throughout the entire vector population. Gene drives only affect sexually reproducing species, and thus they cannot be used directly on bacterial and viral pathogens.

Malaria transmission has been used as a test case to explore use of a vector gene drive to contain the spread of a disease. The results have been encouraging. In 2015, 200 million people worldwide were infected with malaria and between 500,000 and 700,000 died from the disease. Seventy-two percent of these were children under 5 years of age. In 2016, the number of cases worldwide increased to 216 million. Of 3,500 mosquito species, only those that belong to a subset called Anopheles can transmit the malaria parasite, Plasmodium falciparum , to a human by means of a bite from a female. The Anopheles stephensi mosquito, endemic to India and South Asia, carries the malaria parasite in that region. These mosquitoes were experimentally gene edited so that they could no longer carry the malaria parasite, establishing a population modification gene drive. A key trick in a gene drive is to engineer both copies of the chromosome so that all the offspring of a mating between a normal mosquito and a genetically altered one carry the genetic profile of the desired alteration, rather than just half the offspring, which is normally the case. Under laboratory conditions, it was demonstrated that this population modification drive leads to rapid spread of the desired genetically-altered mosquito and disappearance of the normal mosquitoes. The genetically altered mosquitoes cannot harbor the malaria parasite. This suggests that release of this genetically altered mosquito into the wild would halt the spread of malaria and thus save millions of lives. Eventually the malaria parasite could naturally mutate to overcome the genetic change in its mosquito host allowing it to once again infect humans, but this might not occur for a long time.

Another example is the Anopheles gambiae mosquito, which transmits malaria in sub-Saharan Africa. In another series of gene drive experiments, gene editing was used to change genes that the female mosquito needs for egg production, thereby creating female sterility (a suppression gene drive). In this case, the goal was just to reduce the number of mosquitoes transmitting malaria, but the technique could potentially wipe out the entire population of Anopheles gambiae . The combined challenge of climate change, which is altering the geographic distribution of the vector mosquitoes, and growing resistance to drugs routinely used to treat malaria-infected patients is making gene editing of the insect vectors an increasingly attractive potential solution. However, the notion of eliminating an entire insect species troubles many people.

In another test case, gene drives are being explored as a way of controlling transmission of Lyme disease by ticks on the U.S. island of Nantucket. Owing to recent increases in the population of island ticks, over 40% of the 10,000 inhabitants of Nantucket have, or have had, Lyme disease. Both deer and the white foot mouse can transmit the Lyme disease pathogen, Borrelia burgdorferi bacteria, to ticks, and the pathogen can then be transmitted to humans by the ticks. Ticks feed on the deer or white foot mice carrying Borrelia and the infected ticks bite humans, passing on Lyme disease. A plan was proposed by Kevin Esvelt (MIT) and Sam Telford (Tufts U., Cummings School of Veterinary Medicine) to use a gene drive to reduce the population of white footed mice that are infected with Borrelia . To do this, the mice would be genetically engineered so that they are immune to infection by the Lyme disease bacterial pathogen and thus could not accumulate infectious Borrelia . In this case, there would still be the same number of mice and the same number of ticks, but the number of ticks able to transmit Borrelia would be significantly reduced. Thousands of altered mice would be released on the island. The gene drive would ensure that the genetic alteration would pass down through all following generations of mice on the island, disrupting the cycle of transmission. The plan is to first test the genetically modified mice on an uninhabited island and then, with the concurrence of the inhabitants of both Nantucket Island and Martha’s Vineyard, release the genetically altered mice. The first step will be to get the concurrence and support of the inhabitants of these islands, because the gene drive would be altering the environment shared by all inhabitants.

Recently, a new gene editing application has been developed to alter the response of plants to environmental challenges. The proposed scheme involves spraying a field of plants with millions of insect vectors carrying viruses that are programmed to edit the genome of a plant such as maize to become drought resistant, in one growing season. This technique would be significantly faster than a gene drive. Further, this method would not permanently alter the genetic makeup of future plant generations, as is the case with gene drives. The goal is to engineer drought-resistant and temperature-tolerant plants, thereby securing the food supply during times of climate instability. But there is a catch, as once released into the wild, controlling these insect vectors would be difficult, if not impossible. As a result, this work has been limited so far to the laboratory. There is also concern that the method could be adapted as a biological weapon, enabling destruction of targeted food crops over wide areas by adverse genetic manipulation of the plants’ chromosomes. In addition to controlling mosquito vectors and tick-borne Lyme disease, gene drives are also being devised to control the nematode worms that carry the parasite causing Schistosomiasis.

Gene drives have not yet been released in the wild to mitigate vector-borne transmission of disease as there are critical questions to be resolved as noted above. Although the biology is ready, there are many questions of governance, safety, and ethics to be answered. Caution is important, since once the genetically-altered vectors are released, there is no assured way of controlling them at this point.

In July 2015, the U.S. National Academy of Sciences convened a meeting to discuss “the promise and perils of gene drives.” Critical questions raised at the meeting were:

Will an entire species of vector be wiped out? Methods are being devised to slow the gene drive so that only a portion of the offspring contain the genetically engineered alterations. These “Daisy chain drives,” have been engineered to be self-limiting and eventually disappear from the population.

Have techniques been devised that could control a runaway gene drive? By creating a second gene drive that undoes the genetic alterations of the first gene drive, essentially “a molecular eraser,” it is hoped a gene drive could be reversed, but not before unintended consequences to the ecosystem become apparent.

Can the altered genetic traits be transferred to other insect species ? Unlikely, but possible. If this occurred, the potential for wiping out beneficial insect species would lead to further ecological disruptions, compounding the ravages of climate change.

Global Warming Mitigation Will Require a Coordinated International Effort

Many climate scientists and other thoughtful people have had concerns about the deteriorating global ecosystem for several decades now. The contribution of human activity to this escalating cataclysm is well documented. Predictions of dire consequences have been noted and sporadic attempts by the international community have been made to mitigate the ongoing onslaught of carbon emissions. But global warming is a problem that can only be solved by global cooperation because the world’s ecosystem is an integrated system. The causes of environmental degradation cannot be addressed by a patchwork of uncoordinated responses. We are dependent upon achieving international cooperation to mount a coordinated, science-based response.

In the United States today, political calculations relating to oil and coal interests have halted government acknowledgement of the risks of continuing future emissions of CO 2 into the atmosphere. In December 2018, at a UN Climate Change Conference in Poland, Wells Griffith, Mr. Trump’s international energy and climate adviser, said “We strongly believe that no country should have to sacrifice their economic prosperity or energy security in pursuit of environmental sustainability.” The attendees broke into jeers and mocking laughter. 24 Do not think that the United States is alone in this stance. We are aligned with other major fossil fuel producing nations, including Russia, Saudi Arabia, Kuwait, and Australia. We are now well beyond the time of debating about validity of the predictions about what will happen if climate change is left unaddressed. Rather, we are trying to mitigate what has already happened, while, as a society, summoning the courage and the will to leave fossil fuels in the ground and switch to alternative energy sources. Renewable power resources and improvements in the efficiency of our energy use can be important components of our energy future for the rest of this century. But, practically speaking, nuclear power will probably also have to be a major component of the future energy portfolio in order to meet world energy demands while greatly reducing use of fossil fuels. 25, 26 That too is controversial. These are existential choices that call for an unprecedented level of wisdom and societal responsiveness in the world’s political systems. It does seem likely that achieving the necessary global political response will only come when there is widespread public fear and panic as the realization of the danger percolates into public consciousness. 27 It is extraordinary that the current U.S. national leadership both denies existence of the global warming problem and actively promotes more use of fossil fuels. The longer we delay reduction in global CO 2 emissions, the worse the ultimate catastrophe will be.

Authors’ Note:

We believe the world energy economy must shift rapidly from reliance on fossil fuels—coal, oil, and gas—to cleaner alternatives or our children and grandchildren will suffer dire consequences. We encourage the reader to personally assess the risks and potential solutions. To that end, we have included references for further reading that are openly accessible on the Internet.

Lucy Shapiro is a professor in the Department of Developmental Biology at Stanford University School of Medicine where she holds the Virginia and D. K. Ludwig Chair in Cancer Research and is the director of the Beckman Center for Molecular and Genetic Medicine. Harley McAdams is an emeritus professor at the Department of Developmental Biology at Stanford University School of Medicine.

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What Is Climate Change?

Climate change is a long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates. These changes have a broad range of observed effects that are synonymous with the term.

Changes observed in Earth’s climate since the mid-20th century are driven by human activities, particularly fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere, raising Earth’s average surface temperature. Natural processes, which have been overwhelmed by human activities, can also contribute to climate change, including internal variability (e.g., cyclical ocean patterns like El Niño, La Niña and the Pacific Decadal Oscillation) and external forcings (e.g., volcanic activity, changes in the Sun’s energy output , variations in Earth’s orbit ).

Scientists use observations from the ground, air, and space, along with computer models , to monitor and study past, present, and future climate change. Climate data records provide evidence of climate change key indicators, such as global land and ocean temperature increases; rising sea levels; ice loss at Earth’s poles and in mountain glaciers; frequency and severity changes in extreme weather such as hurricanes, heatwaves, wildfires, droughts, floods, and precipitation; and cloud and vegetation cover changes.

“Climate change” and “global warming” are often used interchangeably but have distinct meanings. Similarly, the terms "weather" and "climate" are sometimes confused, though they refer to events with broadly different spatial- and timescales.

What Is Global Warming?

Global warming is the long-term heating of Earth’s surface observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere. This term is not interchangeable with the term "climate change."

Since the pre-industrial period, human activities are estimated to have increased Earth’s global average temperature by about 1 degree Celsius (1.8 degrees Fahrenheit), a number that is currently increasing by more than 0.2 degrees Celsius (0.36 degrees Fahrenheit) per decade. The current warming trend is unequivocally the result of human activity since the 1950s and is proceeding at an unprecedented rate over millennia.

Weather vs. Climate

“if you don’t like the weather in new england, just wait a few minutes.” - mark twain.

Weather refers to atmospheric conditions that occur locally over short periods of time—from minutes to hours or days. Familiar examples include rain, snow, clouds, winds, floods, or thunderstorms.

Climate, on the other hand, refers to the long-term (usually at least 30 years) regional or even global average of temperature, humidity, and rainfall patterns over seasons, years, or decades.

Find Out More: A Guide to NASA’s Global Climate Change Website

This website provides a high-level overview of some of the known causes, effects and indications of global climate change:

Evidence. Brief descriptions of some of the key scientific observations that our planet is undergoing abrupt climate change.

Causes. A concise discussion of the primary climate change causes on our planet.

Effects. A look at some of the likely future effects of climate change, including U.S. regional effects.

Vital Signs. Graphs and animated time series showing real-time climate change data, including atmospheric carbon dioxide, global temperature, sea ice extent, and ice sheet volume.

Earth Minute. This fun video series explains various Earth science topics, including some climate change topics.

Other NASA Resources

Goddard Scientific Visualization Studio. An extensive collection of animated climate change and Earth science visualizations.

Sea Level Change Portal. NASA's portal for an in-depth look at the science behind sea level change.

NASA’s Earth Observatory. Satellite imagery, feature articles and scientific information about our home planet, with a focus on Earth’s climate and environmental change.

Header image is of Apusiaajik Glacier, and was taken near Kulusuk, Greenland, on Aug. 26, 2018, during NASA's Oceans Melting Greenland (OMG) field operations. Learn more here . Credit: NASA/JPL-Caltech

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10 (page 173) p. 173 Conclusion

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The ‘Conclusion’ confirms that global warming is the major challenge for our global society. There is very little doubt that global warming will change our climate in the next century. So what are the solutions to global warming? First, there must be an international political solution. Second, funding for developing cheap and clean energy production must be increased, as all economic development is based on increasing energy usage. We must not pin all our hopes on global politics and clean energy technology, so we must prepare for the worst and adapt. If implemented now, a lot of the costs and damage that could be caused by changing climate can be mitigated.

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Global Warming Definition, Causes, Effects, Impacts, Solutions

Global Warming is a long-term increase in average global temperature. Read about Global Warming Definition, Causes, Effects, Impact on Climate Change & Solutions for the UPSC exam.

Table of Contents

What is Global Warming?

Global Warming is a long-term increase in average global temperature. It is considered a natural phenomenon, but anthropogenic activities on earth, particularly post Industrial Revolution , have led to an increase in the rate of this temperature increase. Various Reports published by the International Panel on Climate Change (IPCC) have time and again highlighted that since 1850 human activities have led to an increase of about 1 degree Celsius in average global temperature. Most of this warming has taken place in the second half of the 20th century. The fact that 5 of the hottest recorded year have occurred since 2015 can help us better understand the calamitous impact of anthropogenic activities.

Global Warming Causes

Green House Gases also known as GHGs in the atmosphere trap the solar radiations that are reflected by the earth’s surface. Under normal circumstances, most of these radiations escape into outer space. However, the release of GHGs by anthropogenic activities has increased their concentration in the atmosphere. Thus, the earth is getting hotter and hotter. 

Some of the common GHGs include carbon dioxide, methane, nitrous oxide, chlorofluorocarbons, and water vapour, among others. The global warming potential of each GHG is different. For example, methane has a 25-time warming potential than carbon dioxide. Similarly, nitrous oxide has more than 250 times the warming potential than carbon dioxide. The top  anthropogenic activities that are responsible for the release of GHGs are shown below.

Global Warming and Green House Effect

Both phenomena are related to each other. Green House Gases also known as GHGs in the atmosphere trap the solar radiations that are reflected by the earth’s surface. Under normal circumstances, most of these radiations escape into outer space. However, the release of GHGs by anthropogenic activities has increased their concentration in the atmosphere. This is the primary cause of Global Warming . 

Global Warming Effects

Increase in the average temperature of the earth.

According to IPCC reports, human-induced global warming is responsible for nearly 1 degree Celsius temperature rise vis a vis pre-industrial level. Data from NASA suggest that 2016 has been the hottest year on record.

Frequency of Extreme Weather Events is Increasing

Across the globe, extreme weather events have increased in occurrence. For example, forest fires in California have become an annual event. Also, it is increasing in frequency each year. Most recently, we have recorded the phenomena of heat waves in Antarctica. The intensity of cyclones in the Bay of Bengal region has increased. Similarly, the frequency of occurrence of El Niño and La Niña has reduced from once in 8–10 years to once in 3–4 years now. More frequent episodes of floods and drought are being recorded every year across the world.

Melting of Ice

According to IPCC, there is 10% less permafrost in North Hemisphere at present compared to the 1900s. Remote sensing data suggest Arctic ice is melting fast. Experts suggest that not only will the sea level rise with the melting of glaciers, but there is also a danger of new bacteria and viruses being released into the environment which has so far been trapped in ice sheets. This may lead to outbreaks of disease and pandemics which are beyond the control of human medical sciences.

Sea Level Rise and Acidification of Ocean

A report published by WMO, suggests that the rate of sea level rise has doubled for the period between 2013 and 2021 compared to the rate for the period between 1993 and 2002. Earth scientists are suggesting that if this phenomenon continues, many human-inhabited coastal areas will be submerged into the sea in the coming decades. Also, with the concentration of carbon dioxide rising in the atmosphere, oceans are absorbing more of it. This is leading to ocean acidification. The impact of this phenomenon can be disastrous for ocean biodiversity, particularly the coral reefs. 

Adverse Impact on Terrestrial Ecosystems of the Earth

It has been recorded that many flora and fauna species are heading northwards in Northern Hemisphere. Significant changes have been observed in the migratory movements of birds across the world. Early arrival to their summer feeding and breeding grounds is quite evident. Expert biologists suggest that rising temperatures in the tropical and subtropical regions may lead to an outbreak of new diseases, which in turn may render many floral and faunal species extinct.

Social and Economic Impact

A rising number of extreme weather events will have an adverse impact on agriculture and fisheries. Rising global temperatures will have a negative impact on the productivity of human beings, particularly in tropical and subtropical regions of the earth. The impact on life and livelihoods of indigenous people across the world will be even more pronounced. 

Global Warming Solutions

Global cooperation for reduction of emissions.

It is time that the target of containing the global average temperature rise within 1.5 degrees Celsius of pre-industrial levels is taken seriously. Also, global efforts should be based on a spirit of Common But Differentiated Responsibility. This will ensure that historical injustices done to the global south are duly acknowledged, and they have an equal chance to transform themselves into developed countries. Countries must act proactively to achieve Net Zero Emission status at the earliest. 

Transition to Cleaner and Greener Forms of Energy

Thermal power plants based on coal should be made more efficient and inefficient ones should be phased off. Also, mass adoption of renewable forms of energy like solar should be promoted. Similarly, avenues for using hydrogen as energy fuel should be looked into. We must also explore the possibility of Nuclear fusion for energy generation, in addition to making nuclear fission-based energy generation safer.

Changes in Agricultural Practices and Land Use

Agriculture based on the use of nitrogenous fertilizers must be replaced with organic farming techniques. Also, methane gas released from agricultural and cattle waste must be trapped as biogas for domestic usage. Massive afforestation drives must be organized. Urban governments must make it a point to include green spaces in urban planning.

Improving Transportation System

The advent of E-vehicles is a welcome change, but we need to make the batteries used in these vehicles more efficient. Urban planners must make public transportation systems inherent as a benchmark of good urban planning. Also, urban planning should be such that it promotes more walking and cycling habits among the residents. 

Behavioural Changes

All the above discussions will have no meaning if we as individuals are not sensitive enough. We need to make reducing, reusing and recycling a mantra of our living. It should be our civic duty to save water, and wildlife and raise awareness among others. 

Solar Geoengineering

Solar geoengineering, a proposed climate intervention method, aims to counteract global warming by reflecting a portion of the sun’s rays back into space. One prominent approach involves injecting substances like sulphur dioxide into the upper atmosphere to create reflective aerosols. These particles can scatter sunlight, reducing the Earth’s temperature. However, solar geoengineering is a topic of debate, with concerns about its side effects, such as disrupted weather patterns and potential geopolitical risks. Research in this field is ongoing, but it remains a theoretical concept with limited practical implementation.

Can Solar Geoengineering Halt Global Warming?

Solar geoengineering, specifically solar radiation management (SRM), is under scrutiny as a potential method to mitigate global warming. SRM involves reflecting sunlight away from Earth, often by injecting substances like sulphur dioxide into the upper atmosphere to create reflective aerosols. However, its effectiveness remains a subject of debate, with concerns about potential side effects and ethical implications. While research in this field is ongoing, solar geoengineering is currently in a theoretical stage, with limited practical implementation.

Global Warming Conclusion

It is rightly said that “Charity begins at home.” Climate action will be more efficient if we go by this spirit. To begin with, each individual can make sure that what is happening in their house and immediate surroundings is in harmony with the environment. If this can happen, all the policies we are making at the local, national, regional and global levels will give far better results. 

Global Warming UPSC

Each year, we read about rising global temperatures. Also, catching the headlines is the news related to disasters caused by events like cyclones, forest fires, floods and drought. All these phenomena can be attributed to one single cause which is global warming. 

Global Warming is a long-term increase in average global temperature. It is considered a natural phenomenon, but anthropogenic activities on earth, particularly post-Industrial Revolution, have led to an increase in the rate of this temperature increase.

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Why is global warming a problem?

Global Warming at present rate can lead to disastrous impacts like rising sea level, out break of new diseases, extreme weather events among others.

What are 3 causes of global warming?

Human induced green house gas emission due to activities like agriculture, industrial emissions, transportation are the top 3 causes of global warming.

What are 5 effects of global warming?

Rising sea level, out break of new diseases, extreme weather events, changes in biodiversity and melting of glaciers are top 5 effects of global warming.

Why global warming is important?

Global warming at its natural rate is important to keep up the temperature of earth within the range that makes it habitable. This makes global warming important.

Can we control global warming?

Number of mitigation measures like shifting to cleaning forms of energy and transportation can be taken to control global warming.

Who help with global warming?

Global Warming is a collective challenge for entire humanity. Citizens, civil societies, governments and businesses must act in unison to address it.

I, Sakshi Gupta, am a content writer to empower students aiming for UPSC, PSC, and other competitive exams. My objective is to provide clear, concise, and informative content that caters to your exam preparation needs. I strive to make my content not only informative but also engaging, keeping you motivated throughout your journey!

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How global warming is disrupting life on Earth

The signs of global warming are everywhere, and are more complex than just climbing temperatures.

Our planet is getting hotter. Since the Industrial Revolution—an event that spurred the use of fossil fuels in everything from power plants to transportation—Earth has warmed by 1 degree Celsius, about 2 degrees Fahrenheit.  

That may sound insignificant, but 2023 was the hottest year on record , and all 10 of the hottest years on record have occurred in the past decade.  

Global warming and climate change are often used interchangeably as synonyms, but scientists prefer to use “climate change” when describing the complex shifts now affecting our planet’s weather and climate systems.  

Climate change encompasses not only rising average temperatures but also natural disasters, shifting wildlife habitats, rising seas , and a range of other impacts. All of these changes are emerging as humans continue to add heat-trapping greenhouse gases , like carbon dioxide and methane, to the atmosphere.

What causes global warming?

When fossil fuel emissions are pumped into the atmosphere, they change the chemistry of our atmosphere, allowing sunlight to reach the Earth but preventing heat from being released into space. This keeps Earth warm, like a greenhouse, and this warming is known as the greenhouse effect .  

Carbon dioxide is the most commonly found greenhouse gas and about 75 percent of all the climate warming pollution in the atmosphere. This gas is a product of producing and burning oil, gas, and coal. About a quarter of Carbon dioxide also results from land cleared for timber or agriculture.  

Methane is another common greenhouse gas. Although it makes up only about 16 percent of emissions, it's roughly 25 times more potent than carbon dioxide and dissipates more quickly. That means methane can cause a large spark in warming, but ending methane pollution can also quickly limit the amount of atmospheric warming. Sources of this gas include agriculture (mostly livestock), leaks from oil and gas production, and waste from landfills.  

What are the effects of global warming?  

One of the most concerning impacts of global warming is the effect warmer temperatures will have on Earth's polar regions and mountain glaciers. The Arctic is warming four times faster than the rest of the planet. This warming reduces critical ice habitat and it disrupts the flow of the jet stream, creating more unpredictable weather patterns around the globe.  

( Learn more about the jet stream. )

A warmer planet doesn't just raise temperatures. Precipitation is becoming more extreme as the planet heats. For every degree your thermometer rises, the air holds about seven percent more moisture. This increase in moisture in the atmosphere can produce flash floods, more destructive hurricanes, and even paradoxically, stronger snow storms.  

The world's leading scientists regularly gather to review the latest research on how the planet is changing. The results of this review is synthesized in regularly published reports known as the Intergovernmental Panel on Climate Change (IPCC) reports.  

A recent report outlines how disruptive a global rise in temperature can be:

• Coral reefs are now a highly endangered ecosystem. When corals face environmental stress, such as high heat, they expel their colorful algae and turn a ghostly white, an effect known as coral bleaching . In this weakened state, they more easily die.  
• Trees are increasingly dying from drought , and this mass mortality is reshaping forest ecosystems.
• Rising temperatures and changing precipitation patterns are making wildfires more common and more widespread. Research shows they're even moving into the eastern U.S. where fires have historically been less common.
• Hurricanes are growing more destructive and dumping more rain, an effect that will result in more damage. Some scientists say we even need to be preparing for Cat 6 storms . (The current ranking system ends at Cat 5.)

How can we limit global warming?  

Limiting the rising in global warming is theoretically achievable, but politically, socially, and economically difficult.  

Those same sources of greenhouse gas emissions must be limited to reduce warming. For example, oil and gas used to generate electricity or power industrial manufacturing will need to be replaced by net zero emission technology like wind and solar power. Transportation, another major source of emissions, will need to integrate more electric vehicles, public transportation, and innovative urban design, such as safe bike lanes and walkable cities.  

( Learn more about solutions to limit global warming. )

One global warming solution that was once considered far fetched is now being taken more seriously: geoengineering. This type of technology relies on manipulating the Earth's atmosphere to physically block the warming rays of the sun or by sucking carbon dioxide straight out of the sky.

Restoring nature may also help limit warming. Trees, oceans, wetlands, and other ecosystems help absorb excess carbon—but when they're lost, so too is their potential to fight climate change.  

Ultimately, we'll need to adapt to warming temperatures, building homes to withstand sea level rise for example, or more efficiently cooling homes during heat waves.  

Related Topics

• CLIMATE CHANGE
• ENVIRONMENT AND CONSERVATION
• POLAR REGIONS

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How Extreme Heat Is Threatening Education Progress Worldwide

Children today face many more extreme weather hazards that can undermine global gains in education.

By Somini Sengupta

The continued burning of fossil fuels is closing schools around the world for days, sometimes weeks at a time, and threatening to undermine one of the greatest global gains of recent decades: children’s education.

It’s a glimpse into one of the starkest divides of climate change. Children today are living through many more abnormally hot days in their lifetimes than their grandparents, according to data released Wednesday by Unicef, the United Nations Children’s Fund.

Consider the scale of some recent school closures.

Pakistan closed schools for half its students, that’s 26 million children, for a full week in May, when temperatures were projected to soar to more than 40 degrees Celsius. Bangladesh shuttered schools for half its students during an April heat wave, affecting 33 million children. So too South Sudan in April. The Philippines ordered school closures for two days , when heat reached what the country’s meteorological department called “danger” levels.

And in the United States, heat days prompted school closures or early dismissal in districts from Massachusetts to Colorado during the last school year. They still represent a small share of total school days, though one recent estimate suggests that the numbers are increasing quickly, from about three days a year a few years ago to double that number now, with many more expected by midcentury.

In short, heat waves, exacerbated by the accumulation of planet-heating gases in the atmosphere, are making it harder to learn. Even if schools are open, extremely high temperatures, especially over several hours, affects learning outcomes , including test scores, research shows .

“We are deeply concerned that the number of extreme heat days is going to indirectly lead to learning loss,” Lily Caprani, chief of advocacy for Unicef, said in a telephone interview on Tuesday.

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Climate Change: Evidence and Causes: Update 2020 (2020)

Chapter: conclusion, c onclusion.

This document explains that there are well-understood physical mechanisms by which changes in the amounts of greenhouse gases cause climate changes. It discusses the evidence that the concentrations of these gases in the atmosphere have increased and are still increasing rapidly, that climate change is occurring, and that most of the recent change is almost certainly due to emissions of greenhouse gases caused by human activities. Further climate change is inevitable; if emissions of greenhouse gases continue unabated, future changes will substantially exceed those that have occurred so far. There remains a range of estimates of the magnitude and regional expression of future change, but increases in the extremes of climate that can adversely affect natural ecosystems and human activities and infrastructure are expected.

Citizens and governments can choose among several options (or a mixture of those options) in response to this information: they can change their pattern of energy production and usage in order to limit emissions of greenhouse gases and hence the magnitude of climate changes; they can wait for changes to occur and accept the losses, damage, and suffering that arise; they can adapt to actual and expected changes as much as possible; or they can seek as yet unproven “geoengineering” solutions to counteract some of the climate changes that would otherwise occur. Each of these options has risks, attractions and costs, and what is actually done may be a mixture of these different options. Different nations and communities will vary in their vulnerability and their capacity to adapt. There is an important debate to be had about choices among these options, to decide what is best for each group or nation, and most importantly for the global population as a whole. The options have to be discussed at a global scale because in many cases those communities that are most vulnerable control few of the emissions, either past or future. Our description of the science of climate change, with both its facts and its uncertainties, is offered as a basis to inform that policy debate.

A CKNOWLEDGEMENTS

The following individuals served as the primary writing team for the 2014 and 2020 editions of this document:

• Eric Wolff FRS, (UK lead), University of Cambridge
• Inez Fung (NAS, US lead), University of California, Berkeley
• Brian Hoskins FRS, Grantham Institute for Climate Change
• John F.B. Mitchell FRS, UK Met Office
• Tim Palmer FRS, University of Oxford
• Benjamin Santer (NAS), Lawrence Livermore National Laboratory
• John Shepherd FRS, University of Southampton
• Keith Shine FRS, University of Reading.
• Susan Solomon (NAS), Massachusetts Institute of Technology
• Kevin Trenberth, National Center for Atmospheric Research
• John Walsh, University of Alaska, Fairbanks
• Don Wuebbles, University of Illinois

Staff support for the 2020 revision was provided by Richard Walker, Amanda Purcell, Nancy Huddleston, and Michael Hudson. We offer special thanks to Rebecca Lindsey and NOAA Climate.gov for providing data and figure updates.

The following individuals served as reviewers of the 2014 document in accordance with procedures approved by the Royal Society and the National Academy of Sciences:

• Richard Alley (NAS), Department of Geosciences, Pennsylvania State University
• Alec Broers FRS, Former President of the Royal Academy of Engineering
• Harry Elderfield FRS, Department of Earth Sciences, University of Cambridge
• Joanna Haigh FRS, Professor of Atmospheric Physics, Imperial College London
• Isaac Held (NAS), NOAA Geophysical Fluid Dynamics Laboratory
• John Kutzbach (NAS), Center for Climatic Research, University of Wisconsin
• Jerry Meehl, Senior Scientist, National Center for Atmospheric Research
• John Pendry FRS, Imperial College London
• John Pyle FRS, Department of Chemistry, University of Cambridge
• Gavin Schmidt, NASA Goddard Space Flight Center
• Emily Shuckburgh, British Antarctic Survey
• Gabrielle Walker, Journalist
• Andrew Watson FRS, University of East Anglia

The Support for the 2014 Edition was provided by NAS Endowment Funds. We offer sincere thanks to the Ralph J. and Carol M. Cicerone Endowment for NAS Missions for supporting the production of this 2020 Edition.

F OR FURTHER READING

For more detailed discussion of the topics addressed in this document (including references to the underlying original research), see:

• Intergovernmental Panel on Climate Change (IPCC), 2019: Special Report on the Ocean and Cryosphere in a Changing Climate [ https://www.ipcc.ch/srocc ]
• National Academies of Sciences, Engineering, and Medicine (NASEM), 2019: Negative Emissions Technologies and Reliable Sequestration: A Research Agenda [ https://www.nap.edu/catalog/25259 ]
• Royal Society, 2018: Greenhouse gas removal [ https://raeng.org.uk/greenhousegasremoval ]
• U.S. Global Change Research Program (USGCRP), 2018: Fourth National Climate Assessment Volume II: Impacts, Risks, and Adaptation in the United States [ https://nca2018.globalchange.gov ]
• IPCC, 2018: Global Warming of 1.5°C [ https://www.ipcc.ch/sr15 ]
• USGCRP, 2017: Fourth National Climate Assessment Volume I: Climate Science Special Reports [ https://science2017.globalchange.gov ]
• NASEM, 2016: Attribution of Extreme Weather Events in the Context of Climate Change [ https://www.nap.edu/catalog/21852 ]
• IPCC, 2013: Fifth Assessment Report (AR5) Working Group 1. Climate Change 2013: The Physical Science Basis [ https://www.ipcc.ch/report/ar5/wg1 ]
• NRC, 2013: Abrupt Impacts of Climate Change: Anticipating Surprises [ https://www.nap.edu/catalog/18373 ]
• NRC, 2011: Climate Stabilization Targets: Emissions, Concentrations, and Impacts Over Decades to Millennia [ https://www.nap.edu/catalog/12877 ]
• Royal Society 2010: Climate Change: A Summary of the Science [ https://royalsociety.org/topics-policy/publications/2010/climate-change-summary-science ]
• NRC, 2010: America’s Climate Choices: Advancing the Science of Climate Change [ https://www.nap.edu/catalog/12782 ]

Much of the original data underlying the scientific findings discussed here are available at:

• https://data.ucar.edu/
• https://climatedataguide.ucar.edu
• https://iridl.ldeo.columbia.edu
• https://ess-dive.lbl.gov/
• https://www.ncdc.noaa.gov/
• https://www.esrl.noaa.gov/gmd/ccgg/trends/
• http://scrippsco2.ucsd.edu
• http://hahana.soest.hawaii.edu/hot/

Climate change is one of the defining issues of our time. It is now more certain than ever, based on many lines of evidence, that humans are changing Earth's climate. The Royal Society and the US National Academy of Sciences, with their similar missions to promote the use of science to benefit society and to inform critical policy debates, produced the original Climate Change: Evidence and Causes in 2014. It was written and reviewed by a UK-US team of leading climate scientists. This new edition, prepared by the same author team, has been updated with the most recent climate data and scientific analyses, all of which reinforce our understanding of human-caused climate change.

Scientific information is a vital component for society to make informed decisions about how to reduce the magnitude of climate change and how to adapt to its impacts. This booklet serves as a key reference document for decision makers, policy makers, educators, and others seeking authoritative answers about the current state of climate-change science.

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