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The scientific evidence is unequivocal. Natural climate variability alone cannot explain this trend. Human activities, especially the burning of coal and oil, have warmed the earth by dramatically increasing the concentrations of heat-trapping gases in the atmosphere. The more of these gases humans put into the atmosphere, the more the earth will warm in the decades and centuries ahead. The impacts of warming can already be observed throughout the United States, from rising sea levels to melting snow and ice to more drought and extreme rainfall. Climate change is already affecting ecosystems, freshwater supplies, and human health around the world. Although some amount of climate change is now unavoidable, much worse impacts can be avoided by substantially reducing the amount of heat-trapping gases released into the atmosphere.
For more information on the science and impacts of climate change, be sure to listen to our Climate Change 101 podcast series