Robust but weak winter atmospheric circulation response to future Arctic sea ice loss

The degree to which Arctic sea ice decline influences the mid-latitude atmospheric circulation is widely debated. Here, the authors use a coordinated multi-model experiment to show that Arctic sea ice loss causes a weakening of the mid-latitude westerly winds, but the effect is overall small. The po...

Full description

Bibliographic Details
Published in:Nature Communications
Main Authors: Smith, D., Eade, R., Andrews, M., Ayres, H., Clark, A., Chripko, S., Deser, C., Dunstone, N., Garcia-Serrano, J., Gastineau, G., Graff, L., Hardiman, S., He, B., Hermanson, L., Jung, T., Knight, J., Levine, X., Magnusdottir, G., Manzini, E., Matei, D., Mori, M., Msadek, R., Ortega, P., Peings, Y., Scaife, A., Screen, J., Seabrook, M., Semmler, T., Sigmond, M., Streffing, J., Sun, L., Walsh, A.
Format: Article in Journal/Newspaper
Language:English
Published: 2022
Subjects:
Arctic
North Atlantic
North Atlantic oscillation
Sea ice
Online Access:http://hdl.handle.net/21.11116/0000-000A-07D8-B
http://hdl.handle.net/21.11116/0000-000A-07DB-8
Description
Summary:The degree to which Arctic sea ice decline influences the mid-latitude atmospheric circulation is widely debated. Here, the authors use a coordinated multi-model experiment to show that Arctic sea ice loss causes a weakening of the mid-latitude westerly winds, but the effect is overall small. The possibility that Arctic sea ice loss weakens mid-latitude westerlies, promoting more severe cold winters, has sparked more than a decade of scientific debate, with apparent support from observations but inconclusive modelling evidence. Here we show that sixteen models contributing to the Polar Amplification Model Intercomparison Project simulate a weakening of mid-latitude westerlies in response to projected Arctic sea ice loss. We develop an emergent constraint based on eddy feedback, which is 1.2 to 3 times too weak in the models, suggesting that the real-world weakening lies towards the higher end of the model simulations. Still, the modelled response to Arctic sea ice loss is weak: the North Atlantic Oscillation response is similar in magnitude and offsets the projected response to increased greenhouse gases, but would only account for around 10% of variations in individual years. We further find that relationships between Arctic sea ice and atmospheric circulation have weakened recently in observations and are no longer inconsistent with those in models.

Similar Items