Arctic amplification dominated by temperature feedbacks in contemporary climate models

Abstract

Climate change is amplified in the Arctic region. Arctic amplification has been found in past warm1 and glacial periods, as well as in historical observations and climate model experiments. Feedback effects associated with temperature, water vapour and clouds have been suggested to contribute to amplified warming in the Arctic, but the surface albedo feedback—the increase in surface absorption of solar radiation when snow and ice retreat—is often cited as the main contributor. However, Arctic amplification is also found in models without changes in snow and ice cover. Here we analyse climate model simulations from the Coupled Model Intercomparison Project Phase 5 archive to quantify the contributions of the various feedbacks. We find that in the simulations, the largest contribution to Arctic amplification comes from a temperature feedbacks: as the surface warms, more energy is radiated back to space in low latitudes, compared with the Arctic. This effect can be attributed to both the different vertical structure of the warming in high and low latitudes, and a smaller increase in emitted blackbody radiation per unit warming at colder temperatures. We find that the surface albedo feedback is the second main contributor to Arctic amplification and that other contributions are substantially smaller or even opposeArctic amplification

Effects of Arctic geoengineering on precipitation in the tropical monsoon regions

“…This larger warming in the polar regions is known as polar amplification and occurs mostly due to the icealbedo, temperature and water vapor feedbacks that operate strongly at higher latitudes (Collins et al 2013;Pithan and Mauritsen 2014). Polar amplification is robustly seen in climate model simulations of climate change (Holland and Bitz 2003) and has also been observed in late twentieth century data (Vaughan et al 2013;Stroeve et al 2012).…”

Global Contributions of Incoming Radiation and Land Surface Conditions to Maximum Near‐Surface Air Temperature Variability and Trend

“…It depends on atmospheric conditions, such as cloud cover (e.g., Stephens & Webster, 1981), water vapor (Compo & Sardeshmukh, 2009), or greenhouse gas concentrations (Arrhenius, 1896) and includes thus both short‐term weather and long‐term climate effects (Philipona et al, 2005; Pithan & Mauritsen, 2014). …”

Mechanisms influencing seasonal to inter-annual prediction skill of sea ice extent in the Arctic Ocean in MIROC

“…Sea ice reduction resulting from climate change is one of the main processes contributing to Arctic amplification (e.g., Pithan and Mauritsen, 2014). Arctic summer sea ice extent has declined at about 14 % per decade (National Snow and Ice Data Center, 2016, http://nsidc.org/arcticseaicenews/).…”