Global warming has sped up since around 2015, according to a new analysis from the Potsdam Institute for Climate Impact Research (PIK). By comparison, the average warming rate from 1970 to 2015 was just under 0.2°C per decade. Study Does Not Identify the CauseThe research was designed to detect and measure the statistical acceleration, not to determine exactly why it has occurred. They do not predict every short-term fluctuation perfectly, but they help scientists evaluate long-term climate patterns and possible future changes. The 1.5°C limit refers to the goal of restricting long-term global warming to 1.5°C above preindustrial temperatures.