March 2019 Global Temperature Update
March 2019 was the 3rd warmest March in the 140-year instrumental record, at +1.11°C relative to the 1951-1980 mean (2016 was +1.31°C, 2017 was +1.13°C). Tell that to people in the Northern and Midwestern United States, regions hit by brutal cold and heavy snow!
The map of temperature anomalies shows regions in the Arctic that were more than 10°C (about 20°F) above normal (1951-1980 mean) on monthly average! Such Arctic warmth is not from local heating; it is warm air from lower latitudes. Of course, the imported air is balanced by Arctic air moving out – the 48 United States being the recipient in this case.
Polar amplification of global warming causes the jet stream to be less tightly wound, which may increase the chance of cold air outbreaks to middle latitudes. However, March, as the transition month from winter to warmer seasons, always has highly variable weather, as shown by the maps below for the last six years. And Jonathan Erdman of weather.com (http://www.columbia.edu/…/Te…/Emails/Erdman_MarchWeather.pdf) argues that March is mainly a winter month.