Two recent scientific papers – one an analysis by NASA in May, 2016, the other a study by Scripps Institute of Oceanography in July, 2016, – confirm that earth’s cloud cover is gradually moving toward the north and south poles, cloud tops are rising higher into the atmosphere, and boundaries of the tropical zone are expanding.
Clouds play a key role in heating and cooling the planet. When they are present, they reflect solar energy back into space, and shade the earth below. Without clouds, when skies are clear, solar energy beats down directly onto earth’s surface.
The tropical zone currently runs from 30° south latitude to 30° north latitude. Cities on the 30° north latitude line are Cairo, Egypt, and Jacksonville Florida. As cloud cover moves toward the North Pole in the northern hemisphere, and the South Pole in the southern hemisphere, more and more of earth’s surface will fall within the tropical zone. Cities and farmland now in moderate climate zones will gradually be exposed to more sun, and become hotter and dryer.
The NASA analysis, led by scientists at the Goddard Space Flight Center in Maryland, attribute the poleward shift of the clouds to major changes in air circulation relating to the expansion of the tropical zone.
According to the Scripps study, “these findings confirm predictions from computer climate models that changes that took place during the last several decades were consequences of accumulation of greenhouse gases in the atmosphere generated by human populations.” The NASA study concurs.
Fossil fuel emissions pump over 100 billions of tons of CO2 and other pollutants into our atmosphere every year, heating our planet, acidifying our oceans, and stripping away our cloud cover. All are good reasons to accelerate the change over from the carbon energy to renewable energy.