A - Evidence for man-made global warming has reached a “gold standard” level of certainty, adding pressure for cuts in greenhouse gases to limit rising temperatures, scientists said on Monday. “Humanity cannot afford to ignore such clear signals,” the US-led team wrote in the journal Nature Climate Change of satellite measurements of rising temperatures over the past 40 years.
Satellite data Monday’s findings, by researchers in the United States, Canada and Scotland, said evidence for global warming reached the five sigma level by 2005 in two of three sets of satellite data widely used by researchers, and in 2016 in the third. Professor John Christy, of the University of Alabama in Huntsville which runs the third set of data, said there were still many gaps in understanding climate change. His data show a slower pace of warming than the other two sets.