Premium
Intermodel Spread in the Northern Hemisphere Stratospheric Polar Vortex Response to Climate Change in the CMIP5 Models
Author(s) -
Wu Yutian,
Simpson Isla R.,
Seager Richard
Publication year - 2019
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2019gl085545
Subject(s) - polar vortex , coupled model intercomparison project , environmental science , northern hemisphere , polar , climatology , atmospheric sciences , sudden stratospheric warming , zonal and meridional , vortex , climate change , stratosphere , climate model , meteorology , physics , geology , oceanography , astronomy
This study investigates the intermodel spread of the Northern Hemisphere winter stratospheric polar vortex change to anthropogenic greenhouse gas increase in Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Previous proposed mechanisms for the polar vortex response to climate change, based on analysis of atmosphere‐only models, are found inadequate to explain the intermodel spread in the coupled models in CMIP5. It is further found that resolved stationary wave driving in the polar vortex region accounts for less than 30% of the intermodel spread, and intermodel differences in both the vertical and meridional wave propagation contribute to differences in the wave driving. The results call for a detailed budget analysis of the stratospheric circulation response by including both the resolved and parameterized processes through the Dynamics and Variability Model Intercomparison Project. The results also highlight a need for an improved theoretical understanding of future projected polar vortex change and intermodel spread.