Bias of Arctic surface temperature in December-January-February (DJF) during 1979-2005 relative to ERA-Interim reanalysis data from two models. Left: Model with improved spectral-dependent surface emissivity CESM-ϵ(ν). Right: The default CESM-LME. Credit: Kuo et al., 2018, Figure 2a and 2b
Source: Journal of Geophysical Research: Atmospheres

Climate models commonly simulate too cold surface temperatures in the Arctic. In the Community Earth System Model (CESM), the systematic cold bias in the winter is about 7 Kelvin degrees when averaged over the Arctic. Kuo et al. [2018] found that using more realistic spectrally resolved surface emissivity can significantly reduce the CESM cold bias to about 1 Kelvin degree. The improved surface emissivity also introduces a longwave equivalent of the positive shortwave albedo feedback that had received little attention before. This positive feedback affects the simulated magnitude of climate variability and change in the Arctic.

Citation: Kuo, C., Feldman, D. R., Huang, X., Flanner, M., Yang, P., & Chen, X. [2018]. Time-dependent cryospheric longwave surface emissivity feedback in the Community Earth System Model. Journal of Geophysical Research: Atmospheres, 123.

—Minghua Zhang, Editor-in-Chief, JGR: Atmospheres

Text © 2018. The authors. CC BY-NC-ND 3.0
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