Probably because weather was really bad, from a human standpoint, during that time frame, particularly the 60’s and 70’s, when the concern was global cooling
(SMH) The World Meteorological Organisation says it’s time to shift climate baselines because global warming is increasingly setting a new “normal†for weather conditions.
The widely used 1961-90 baseline should be retained as a “stable reference” for climate study but a more current data set – updated every decade – should be adopted to gauge changes in heatwave and rainstorm frequency already under way, the WMO said.
“Rising atmospheric concentrations of greenhouse gases are changing the Earth’s climate much faster than before,†the United Nations agency said in a statement . “As a result, decision-makers in climate-sensitive industries may be basing important decisions on information that may be out of date.â€
Under the recommendations, all countries would start using the most recent 30-year period, 1981-2010, as the new baseline. This would be updated to the 1991-2020 period in 2021, and revised each decade afterwards.
This might not work out too well for them, since there has been a pause going on since 1996, roughly half of the time period. Hurricane activity, wildfires, and tornadoes, among others, have been dropping to historical lows.
