1. The Science of Rapid Climate Change in Alaska and the Arctic: Sea Ice, Land Ice, and Sea Level
- Author:
- John P. Holdren
- Publication Date:
- 08-2023
- Content Type:
- Policy Brief
- Institution:
- Belfer Center for Science and International Affairs, Harvard University
- Abstract:
- The Earth’s surface north of the Arctic Circle, which includes nearly a third of Alaska, is warming 3-4 times faster than the global average.1 Alaska as a whole is warming twice as fast as the lower 48 states.2 As is true for most of the manifestations of anthropogenic climate change, moreover, the extremes of temperature are growing faster than the averages: the highest-ever temperature north of the Arctic Circle—100.4°F—was recorded in Verkhoyansk, Siberia, in June 2020;3 Anchorage reached an all-time high of 90°F on July 4, 2019;4 and Utqiavgik, Alaska, the northernmost U.S. city, reached an all-time winter high of 40°F in December 2022.5 The reasons warming is so fast in the Far North are quite well understood scientifically. The most important factor is the ice-snow-albedo feedback, in which warming reduces the area of land and water covered by ice and snow, which means less reflectivity and more absorption of incident solar energy at the surface, hence further warming.
- Topic:
- Climate Change, Environment, Carbon Emissions, and Sea Ice
- Political Geography:
- North America, Alaska, Arctic, and United States of America