New Arctic Sea ice low
26th March, 2015
As a winter risk management company we would usually be delighted at reducing levels of ice, but this week it has been announced that the levels of sea ice in the Arctic Ocean are at their lowest levels since satellite monitoring began in 1979. The Arctic sea ice follows an annual cycle - freezing during the winter months and melting during the spring and summer. It is usually around this time of year that the ‘winter maximum’ is reached.
The winter maximum is the point in the year when the build-up of ice levels in the Arctic Ocean reaches its peak. Data from the National Snow and Ice Data Center (NSIDC) at the University of Colorado shows that the maximum this winter was 14.5 million square kilometres, reached on the 25th February 2015. This figure beats the previous worst, recorded in 2011, by 1%.
Scientists have been aware of a reduction in Arctic sea ice for decades, but this new low brings the possibility of an ice-free Arctic a step closer.
Reduction in Winter Maximum
- 1980: 16.5 million sq. km
- 1990: 16.2 million sq. km
- 2000: 15.4 million sq. km
- 2010: 15.2 million sq. km
- 2015: 14.5 million sq. km
Why Has It Happened?
Whilst it is likely to have had an impact, experts at the NSIDC are wary of blaming global warming entirely for the reduction in sea ice. They point out that there is a natural variability to our planet's weather and one influencing factor this winter has been an unusual configuration to the jet stream.
During February the jet stream formed a pattern across North America which resulted in the eastern half of the United States and Canada experiencing unusually cold air and stormy weather. At the same time the Pacific side of the continent was experiencing sunny and above average temperatures - something that resulted in a low sea ice build-up in the Bering Sea and Sea of Okhotsk.
One of the obvious results of a reduction in sea ice is that eventually we could experience an ice-free Arctic. Predictions for when this could happen vary greatly and researcher's estimates range from some time in the next 10 years to 2100.
It is not expected that every last ice floe will melt and we are not going to see the Arctic Ocean transformed into the Caribbean Sea. As winter temperatures fall below zero the ice will continue to form, with ‘ice-free’ used to describe when the sea ice is at its minimum during the summer months.
You can see how the levels of ice in the Arctic fluctuated this winter by watching this video from NASA's Goddard Space Flight Center.