Sunday, August 3, 2014

Arctic Sea Ice, Temperatures Indicative of Winter Ahead

Latest observations of Arctic sea ice anomalies, as well as temperature anomalies, may hint at what's to come this winter.

The above graph shows past records of Arctic sea ice over time, categorized by color, with the key on the bottom left. This year's sea ice observations are shown in the thick black line, while 2013's sea ice observations can be viewed by the orange-colored line. Glancing around this chart, it's quite evident that sea ice anomalies in comparison to recent history are above normal this year. Showing itself more recently, these above-normal sea ice anomalies appear to be eclipsing the observations of 2006, which appears to be the highest areal sea ice coverage minimum in the last ten or so years. This recent slowdown of declining ice coverage indicates the presence of cold air over the Arctic Circle, something that stays in that area year-round. What's more important this time, however, is that the cold air is allowing less ice to melt, which in response provides more cold air, and so on and so forth.

The next chart we will analyze is a graph of observed temperatures in the Arctic Circle. The red line on this graph shows observed temperatures, in units of Kelvin. The green line indicates the average temperature for a given date, and the solid blue line depicts the freezing temperature. Arctic temperatures have remained almost completely below average since this spring, a rather remarkable feat. Temperatures currently are above freezing, as is to be expected for the summer season, but observed temperatures remains below the average temperatures. As we discussed earlier, the presence of cold air and slowing of sea ice melt are likely playing into these below normal temperatures in the Arctic.

To break it all down, these developments tell me the chances of a cold winter ahead are being raised. If we were to see low sea ice levels and warm Arctic temperatures, I'd probably root for a warm winter ahead. However, seeing substantial sea ice presence in the northern Hemisphere, as well as consistently below-normal Arctic temperatures, I believe that these factors could play into the risk of another cold winter ahead.