What is the role of the sun and solar cycles in climate change and global warming?
Since 1750, the average amount of energy coming from the sun either remained constant or increased slightly. Estimates of the amount of energy the sun has sent to Earth are based on sunspot records dating back more than two centuries, and other proxy indicators, such as the amount of carbon in tree rings. More recently, satellite observations of solar activity from space suggest a slight increase in solar activity, but the change can’t account for more than 10 percent of the warming trend seen during the past century.
