When I wrote a brief squib last month about the new Holland et al. paper on sea ice decline, I made fun of myself for picking the worst-case scenario, suggesting a “a chance of an ice-free late summer arctic by as soon as 2040.” Apparently I was not alone. In her RealClimate post on the paper and its journalistic aftermath, Cecilia Bitz offers a nice explanation of the work and offers a similar observation to mine. The ice-free 2040 was the most extreme of a number of scenarios:
There is considerable uncertainty in future model projections, and Figs 2 and 4 illustrate why it would be better not to focus too much on the year 2040, which to our dismay was highly publicized.
In understanding why this happened, it is useful to look at the NCAR news relese:
The recent retreat of Arctic sea ice is likely to accelerate so rapidly that the Arctic Ocean could become nearly devoid of ice during summertime as early as 2040, according to new research published in the December 12 issue of Geophysical Research Letters.
In the news release, only the “ice-free in 2040” model run is discussed. It is the model run featured in the animation included with the news release. Is it any surprise that this is the scenario journalists chose to focus on, given that this is what the scientists, through their news release, told them was the most important?