Yes, there are, but the only new process on Earth that has been identified that can account for the significant tipping of Earth's carbon balance is human activity, including deforestation, biomass burning, cement production, and—especially—fossil-fuel emissions.
Yes, human activities exert a cooling influence on Earth in several ways. Overall, this cooling influence is smaller than the warming influence of the heat-trapping gases humans put into the air.
There is overwhelming scientific evidence that Earth is warming and a preponderance of scientific evidence that human activities are the main cause.
Yes, human activity is putting carbon dioxide into the atmosphere faster than natural processes take it out. Rising carbon dioxide levels are strengthening Earth's greenhouse effect and causing global warming.
Considering some locations experience temperature swings of 30°F or more in a single day, warming of 1.8°F (1°C) might seem small, but Earth's annual temperatures are very stable when climate isn't changing.
Our global historical temperature records undergo rigorous quality control and independent peer review. Plus, the proof Earth is warming is practically everywhere you look.
Differences in exposure to sunlight, cloud cover, atmospheric circulation patterns, and other factors influence whether and how much a location is warming or cooling.
With specially designed sensors mounted on their own cars, volunteers in each city will drive pre-planned routes, recording heat and humidity as they go. Scientists will stitch their results into a detailed map showing the hottest parts of each city.
How do we know we can trust the historical surface temperature record? How do we know the rise in carbon dioxide in the atmosphere comes from fossil fuels? Did global warming stop in 1998? Get answers to these and other frequently asked questions.
Much of the western and southern central United States could be in for a warmer-than-average winter this year, while the upper Midwest and Florida peninsula could experience colder-than-average temperatures. Most of California and western Nevada could experience well-below-normal precipitation, while parts of the southeast could receive well-above-normal precipitation.