Global Science Report: Another Indication of Lukewarming

In March 1990, NASA ’s Roy Spencer and University of Alabama-Huntsville’s (UAH) John Christy dropped quite a bomb when they published the first record of lower atmospheric temperatures sensed by satellites’ microwave sounding units (MSUs). While they only had ten years of data, it was crystal clear there was no s ignificant warming trend.It was subsequently discovered by Frank Wentz of Remote Sensing Systems (RSS), a Santa Rosa (CA) consultancy, that the orbits of the sensing satellites successively decay (i.e., become lower) and this results in a spurious but slight cooling trend. Using a record ending in 1995,Wentz showed a slight warming trend of 0.07 ⁰C/decade, about half of what was being observed by surface thermometers. In 1994, Christy and another UAH scientist, Richard McNider, attempted to remove “natural” climate change from the satellite data by backing out El Niño/La Niña fluctuations and the cooling associated with two big volcanoes in 1983 and 1991. They arrived at a warming trend of 0.09⁰C/decade after their removal.Over the years, Spencer and Christy slightly revised their record repeatedly, and its latest iteration shows a total warming trend of 0.13 ⁰C/decade, which includes natural variability. But it is noteworthy that this is biased upward by very warm readings near the end of the record, thanks to the 2015–16 El Niño.Recently, Christy and McNider carried out asimilar analysis to what they did in 1994 and found removing the volca...
Source: Cato-at-liberty - Category: American Health Authors: Source Type: blogs