Astronomical winter starts this weekend in North America and, typically, so do conditions that send us cranking up the heat. But the days they are a-changin’. NOAA tracks the number of heating and cooling degree days by computing the total number of degrees the average daily temperature is below or above 65°F, respectively.Since around 1980, the number of heating degree days has decreased while the number of cooling degree days has increased in the contiguous United States relative to the 20th-century average. What does that mean? Lower demands for heating but higher air conditioning usage.Want to know more? Browse the indicators of global change presented by the U.S. Global Change Research Program (USGCRP).Graphic courtesy of USGCRP, GlobalChange.gov. Animated gif by UNC Asheville’s National Environmental Modeling and Analysis Center (NEMAC).
Link: go.usa.gov/xp76D