claim: A paper by Ross McKitrick, an economics professor at the  University of Guelph, and Patrick Michaels, an environmental studies  professor at the University of Virginia, concludes that half of the  global warming trend from 1980 to 2002 is caused by Urban Heat Island.
evidence: A satellite record revealed that the overall increase in Antarctic sea ice extents reversed in 2014, with rapid rates of decrease in 2014–2017 reducing the Antarctic sea ice extents to their lowest values in the 40-y record.