This graph illustrates the change in global surface temperature relative to average temperatures, with the year tying with for warmest on record Source: NASA's Goddard Institute for Space Studies. Learn more about global surface temperature here.
Images of Change. Explore a stunning gallery of before-and-after images of Earth from land and space that reveal our home planet in a state of flux. Climate Mobile Apps. Keep track of Earth's vital signs, see the planet in a state of flux and slow the pace of global warming with NASA's free mobile apps.
Climate Time Machine. Travel through Earth's recent climate history and see how increasing carbon dioxide, global temperature and sea ice have changed over time. Eyes on the Earth. Global Ice Viewer. Earth's ice cover is shrinking. Sunlight shines onto the Earth's surface, where the energy is absorbed and then radiate back into the atmosphere as heat. In the atmosphere, greenhouse gas molecules trap some of the heat, and the rest escapes into space.
The more greenhouse gases concentrate in the atmosphere, the more heat gets locked up in the molecules. Scientists have known about the greenhouse effect since , when Joseph Fourier calculated that the Earth would be much colder if it had no atmosphere.
This natural greenhouse effect is what keeps the Earth's climate livable. Without it, the Earth's surface would be an average of about 60 degrees Fahrenheit 33 degrees Celsius cooler. In , the Swedish chemist Svante Arrhenius discovered that humans could enhance the greenhouse effect by making carbon dioxide , a greenhouse gas.
He kicked off years of climate research that has given us a sophisticated understanding of global warming. Levels of greenhouse gases have gone up and down over the Earth's history, but they had been fairly constant for the past few thousand years.
Global average temperatures had also stayed fairly constant over that time— until the past years. Through the burning of fossil fuels and other activities that have emitted large amounts of greenhouse gases, particularly over the past few decades, humans are now enhancing the greenhouse effect and warming Earth significantly, and in ways that promise many effects , scientists warn. Human activity isn't the only factor that affects Earth's climate.
Volcanic eruptions and variations in solar radiation from sunspots, solar wind, and the Earth's position relative to the sun also play a role. Changes in solar radiation levels as well as minute particles suspended in the atmosphere from volcanic eruptions , for example, have contributed only about two percent to the recent warming effect.
The balance comes from greenhouse gases and other human-caused factors, such as land use change. The short timescale of this recent warming is singular as well. Volcanic eruptions , for example, emit particles that temporarily cool the Earth's surface. But their effect lasts just a few years. On the other hand, the types of global temperature fluctuations that have contributed to ice ages occur on a cycle of hundreds of thousands of years. For thousands of years now, emissions of greenhouse gases to the atmosphere have been balanced out by greenhouse gases that are naturally absorbed.
As a result, greenhouse gas concentrations and temperatures have been fairly stable, which has allowed human civilization to flourish within a consistent climate. Now, humans have increased the amount of carbon dioxide in the atmosphere by more than a third since the Industrial Revolution. Changes that have historically taken thousands of years are now happening over the course of decades. Also, a new and more unpredictable climate poses unique challenges to all life.
Historically, Earth's climate has regularly shifted between temperatures like those we see today and temperatures cold enough to cover much of North America and Europe with ice. The difference between average global temperatures today and during those ice ages is only about 9 degrees Fahrenheit 5 degrees Celsius , and the swings have tended to happen slowly, over hundreds of thousands of years.
The following charts show how both emissions and temperatures have gone up since , and the projections for how they could continue to change in the future. If we continue on our current path, and emit more and more greenhouse gases, the temperature of the Earth will rise a lot — maybe as much as 5 degrees Celsius 9 degrees Fahrenheit by However, if we reduce our emissions, the temperature of the Earth will still rise but we might be able to keep the rise below 2 degrees Celsius or about 4.
Inventory of U. Each of the past four decades has been warmer than the previous one. According to the National Oceanic and Atmospheric Administration , was the warmest year on record, and the six warmest years have all been since Rising global temperatures threaten human health, increase the risk of some types of extreme weather , and damage ecosystems.
And as the oceans warm and polar ice caps melt, sea levels are rising, endangering coastal areas. These impacts are already being felt today, and groups like the poor, elderly, and those living in conflict areas are especially vulnerable. Learn more about the relationship between extreme weather and climate change. The American pika, a potato-sized relative of the rabbit, could be the first North American mammal to go extinct due to climate change, as warmer temperatures push the creature into higher and higher altitudes, where eventually they will run out of space.
We need to use more clean energy — and use that energy more efficiently — to power everything from our phones to our buildings and factories. We need to drive cars and trucks that use less gasoline or run on electricity or other alternative fuels. Everyone can play a part, including government, businesses, and you.
The first is to reduce the greenhouse gas emissions responsible for climate change. By choosing cleaner ways to power our homes, offices, and cars, and being more efficient and less wasteful, we can produce fewer greenhouse gas emissions. Everyone can play a part in a clean energy future, including government, businesses, and you. There are lot of things you can do to help, like turning off the lights when you leave a room to reduce the electricity you use, taking shorter showers to reduce the water you use and the energy it takes to process, move, and heat it , planting a tree to absorb carbon dioxide, or recycling to reduce waste.
For example, recycling aluminum like soda cans is percent more energy efficient than producing aluminum from raw materials. Look for more ideas on what we can do together and individually.
The second is to prepare for life in a changing climate. Learn how communities and companies are preparing. Whatever your talents are, you can use them to get involved in fighting climate change. Around the world, young people are learning about climate change and taking action. For example, some students are joining together to call on their governments to create strong policies to fight climate change.
Other students are putting their engineering minds to work to invent new technologies to cut emissions or pull greenhouse gases out of the atmosphere. Still others are using their creative talents to bring awareness to climate change by writing songs and creating art. Look for ways to get involved in your community — maybe you can help your school set up a composting program to keep food waste out of the landfill; maybe your church needs help switching to energy efficient lights; maybe you can work with your local government to learn about the ways your community is preparing for extreme weather or wildfires.
Everyone can do something to fight climate change. Check out our Educator Resources page for activities you can do to learn more about how climate change works and how you can be a part of the solution.
As a fully independent organization, C2ES is solely responsible for its positions, programs, and publications. Tags Science At Home. Climate Basics » Climate Classroom. Climate Basics for Kids. The Science Scientific evidence paints a clear picture: Climate change is happening, it is caused in large part by human activity, and it will have many serious and potentially damaging effects in the decades ahead. The Greenhouse Effect The picture below shows the greenhouse effect.
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