Climate Watch
The United Nations’ Intergovernmental Panel on Climate Change released the latest installment of a global assessment of our changing climate and potential futures. Although the report is global in nature, there are a number of important messages for western Alaska. Perhaps the most fundamental is that warming has occurred over the past century is entirely the result of human activities and as such will be with us for a long time into the future. This means that we can expect the kinds of extremes that we’ve seen in recent years, such as the Bering Sea spring sea ice collapse of 2018 and 2019 or the super snowy winter of 2017/18 to be a preview of the future.
Here at the Alaska Center for Climate Assessment Policy at UAF, Dr. Nathan Kettle led a group of researchers who analyzed the frequency and types extreme weather hazards that have been impactful in the greater Nome area since 1990. They used The Nome Nugget and other historical documents to combine the results from that work with projections of how some of the most important hazards may change over the course of the coming decades. One of the most important findings was that some impactful weather events can be expected to change trends over the course of the 21st century. This was the case with the occurrence of heavy snow. Heavy snow, and the accompanying blowing and drifting in Nome is of course a significant problem, exacerbated when big storms occur one right after another. As ocean waters warm and sea ice season becomes shorter, the frequency of big snow storms is expected to increase from historic levels through the 2020s and 2030s, but then decrease (but not go away) starting in the 2040s. The reason for this is simple: As air and ocean temperatures warm beyond a certain point, winter and spring rain is expected to become more frequent, so that even with more precipitation overall in the cold season, more of that will occur as rain. The paper, entitled “Integrating archival analysis, observational data, and climate projections to assess extreme event impacts in Alaska” was published in the journal “Climate Change” in November 2020. If you’d like to read the complete paper it’s available online at https://link.springer.com/article/10.1007/s10584-020-02907-y