Is the Sun causing global warming? https://i.imgur.com/RvqrFy3.jpg The above graph compares global surface temperature changes (red line) and the Sun's energy received by the Earth (yellow line) in watts (units of energy)pe r square meter since 1880. The lighter/thinner lines show the yearly levelswhi le the heavier/thicker lines show the 11-year average trends. Eleven-yearavera ges are used to reduce the year-to-year natural noise in the data, makingthe u nderlying trends more obvious. The amount of solar energy received by the Earth has followed the Sun’s natur al 11-year cycle of small ups and downs with no net increase since the 1950s.O ver the same period, global temperature has risen markedly. It is thereforeext remely unlikely that the Sun has caused the observed global temperature warmin g trend over the past half-century. No. The Sun can influence the Earth’s climate, but it isn’t responsible fort he warming trend we’ve seen over the past few decades. The Sun is a giverof l ife; it helps keep the planet warm enough for us to survive. We know subtlecha nges in the Earth’s orbit around the Sun are responsible for the comingsand g oings of the ice ages. But the warming we’ve seen over the last few decades i s too rapid to be linked to changes in Earth’s orbit, and too large tobe caus ed by solar activity. One of the “smoking guns” that tells us the Sun is not causing global warmin g comes from looking at the amount of the Sun’s energy that hits the top ofth e atmosphere. Since 1978, scientists have been tracking this using sensorson s atellites and what they tell us is that there has been no upward trend inthe a mount of the Sun’s energy reaching Earth. A second smoking gun is that if the Sun were responsible for global warming,we would expect to see warming throughout all layers of the atmosphere, fromthe surface all the way up to the upper atmosphere (stratosphere). But what weactu ally see is warming at the surface and cooling in the stratosphere. Thisis con sistent with the warming being caused by a build-up of heat-trapping gases nea r the surface of the Earth, and not by the Sun getting “hotter.” https://climate.nasa.gov/faq/14/is-the-sun-causing-global-warming/ --

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