Climate Change Causes - NASA
Most climate scientists agree the main cause of the current global warming trend is human expansion of the "greenhouse effect"1 — warming that results when the atmosphere traps heat radiating from Earth toward space. Certain gases in the atmosphere block heat from escaping. Long-lived gases that remain semi-permanently in the atmosphere and do not respond physically or chemically to changes in temperature are described as "forcing" climate change. Gases, such as water vapor, which respond physically or chemically to changes in temperature are seen as "feedbacks." Gases that contribute to the greenhouse effect include: Water vapor. On Earth, human activities are changing the natural greenhouse. The consequences of changing the natural atmospheric greenhouse are difficult to predict, but certain effects seem likely: On average, Earth will become warmer. The role of human activity Solar irradiance Indeed, studies show that solar variability has played a role in past climate changes.
Related: Year 8 - Climate Change
• Climate Change
• CLIMATE CHANGE