New research, led by former Carnegie postdoctoral fellow Summer Praetorius, shows that changes in the heat flow of the northern Pacific Ocean may have a larger effect on the Arctic climate than previously thought. The findings are published in the August 7, 2018, issue of Nature Communications.
The Arctic is experiencing larger and more rapid increases in temperature from global warming more than any other region, with sea-ice declining faster than predicted. This effect, known as Arctic amplification, is a well-established response that involves many positive feedback mechanisms in polar regions.
What has not been well understood is how sea-surface temperature patterns and oceanic heat flow from Earth’s different regions, including the temperate latitudes, affect these polar feedbacks. This new research suggests that the importance of changes occurring in the Pacific may have a stronger impact on Arctic climate than previously recognized.
Paleoclimate records show that climate change in the Arctic can be very large and happen very rapidly. During the last deglaciation, as the planet was starting to warm from rising greenhouse gases, there were two episodes of accelerated warming in the Arctic—with temperatures increasing by 15°C (27°F) in Greenland over the course of decades. Both events were accompanied by rapid warming in the mid-latitude North Pacific and North Atlantic oceans.
Read more at Carnegie Institution for Science
Image: This image was taken in September 2016 showing the extent of Arctic sea ice then. The yellow line shows the average minimum extent of sea ice in the Arctic from 1981 to 2010. (Credit: NASA)