Wednesday, 8 February 2017

Lowest January sea ice volume on record in Arctic

January Arctic Sea Ice Volume is Lowest On Record by a Considerable Margin

7 February, 2017
Almost continuous warm, moist air invasions of the Arctic during fall and winter of 2016 and 2017 have resulted in the lowest sea ice refreeze rates on record. As a result, the amount of ice covering sections of the Northern Hemisphere ocean is now remarkably lower than during past comparable periods. In other words, we’ve never seen a winter in which Northern Hemisphere sea ice was so weak and reduced.
One key measure, sea ice volume, has shown particular losses when compared to past years. And even taking into account a long term trend of ice losses for the northern polar region that has been ongoing since the 20th Century, the 2016-2017 losses stand out like a flashing red indicator light. A trend directly related to the human-forced warming of our world through fossil fuel burning and related greenhouse gas emissions.
(Significant sea ice losses during the winter of 2016-2017 show up clearly in the above PIOMAS graph. PIOMAS is a model measure of sea ice volume. And as you can well see when looking at the red line at the left hand side of the graph, the departure from past years is currently quite large. Image source: PIOMAS.)
In the above PIOMAS graph we find that January sea ice volume averaged around 14,000 cubic kilometers. This reading is roughly comparable to the early July average for the period of 1979 through 2016 — a time when the Arctic saw continuous declines in sea ice. The present reading is also about 1,500 cubic kilometers below the previous record low for the month of January set in 2013. And anyone looking at the above graph can well see that the departure is significantly below the trend line (about 8,000 cubic kilometers below the falling 38 year average for this time of year).
It’s worth reiterating that these are the lowest sea ice volumes ever seen for this time of year in the Arctic. A new record that comes after consistent new record lows occurring throughout the past 38 year period.
Presently, approximate 5 C above average temperatures are dominating the region above the 66 North Latitude. Over the coming days, a pair of warm air invasions of the North Pole region near 90 N are expected to push temperatures to more than 30 degrees Celsius above average and to near the melting point on two separate occasions. This pair of, not at all normal, events will likely produce additional sea ice losses in a polar region that is already seeing very unusual low sea ice concentrations, volumes and extents.