Monday, March 14, 2016

Two Climate Extremes

There are two climate extremes being reported. The Global Monthly Mean Surface Temperature Change in February was more than 1.5 kelvins above pre-industrial temperatures for the first time on record. The 1.5 level is significant because it is the target set just last year by global convention as the endpoint for global warming. That plan is likely not realistic if the world is already flirting with that level of temperature change.

February also saw the lowest Arctic Sea ice for a February by most measures, and now it looks more likely than not that this winter will set new record low maximums for Arctic sea ice. NSIDC Arctic sea ice extent, one of the more reliable and longest-running time series on the subject, peaked early this month at a level slightly below last winter’s record low maximum, then fell off. Extent has been holding steady for a week, and on average, the middle of March is when Arctic ice begins the first phase of its spring decline. A lot could happen in Arctic Ocean weather over the next three weeks, but if nothing too strange happens, the peak set at the beginning of the month will stand as a new record low maximum. Several other Arctic sea ice time series are also showing tentative record low maximums.