EGU2020-4431
https://doi.org/10.5194/egusphere-egu2020-4431
EGU General Assembly 2020
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

An evaluation of East Asian Extratropical cyclones in CMIP5 models and their response to greenhouse warming

Jaeyeon Lee1, Jaeyoung Hwang1, Seok-Woo Son1, and John Gyakum2
Jaeyeon Lee et al.
  • 1School of Earth and Environmental Sciences, Seoul National University, Seoul, Republic of Korea (ljy0330@snu.ac.kr)
  • 2Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Canada

The extratropical cyclones (ETCs) over East Asia and their possible future changes are evaluated using the Coupled Model Intercomparison Project phase 5 (CMIP5) models. The East Asian ETCs are identified using an automated tracking algorithm applied to the 850-hPa relative vorticity field for both reference data (ERA-Interim reanalysis data) and model data. The CMIP5 models well capture the spatial distribution of East Asian ETC properties, although significant biases are present around the high-topography regions. Based on the individual model biases, Best 5 models are selected and used for examining the future changes of East Asian ETCs. In future climate, Best 5 shows declined cyclogenesis in the leeward side of the Tibetan Plateau, which is partly responsible for the decreased ETC frequency over the western North Pacific. The intensity of individual ETCs is also projected to decrease in a warm climate. These changes could be attributed to the combined effect of increased static stability and decreased vertical wind shear in East Asia, which means reduced local baroclinicity. It is also found that CMIP6 models have smaller bias than Best 5 CMIP5 models, indicating that the result documented in this study may change in quantity when newly-available CMIP6 models are utilized.

How to cite: Lee, J., Hwang, J., Son, S.-W., and Gyakum, J.: An evaluation of East Asian Extratropical cyclones in CMIP5 models and their response to greenhouse warming, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-4431, https://doi.org/10.5194/egusphere-egu2020-4431, 2020.