1. Multidecadal Variations in East Asian Winter Temperature Since 1880: Internal Variability Versus External Forcing.
- Author
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Miao, Jiapeng and Jiang, Dabang
- Subjects
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ATLANTIC multidecadal oscillation , *ATMOSPHERIC temperature , *TEMPERATURE , *WINTER , *SURFACE temperature , *GREENHOUSE gases , *TELECONNECTIONS (Climatology) - Abstract
This study investigates the relative contributions of internal variability and external forcing to multidecadal variations in the winter (December–February) East Asian averaged surface air temperature (EASAT) since 1880 by analyzing three observational datasets and large ensemble simulations from 12 coupled models. The results indicate that the internal variability plays a dominant role in the EASAT multidecadal variations. Specifically, the Atlantic Multidecadal Oscillation (AMO) affects the EASAT via an atmospheric teleconnection across the Eurasian continent, and the correlation coefficient between internally generated EASAT variation and the AMO index is −0.49. In comparison, the external forcings only modulate the observed EASAT variations due to offsetting effects of the external forcing agents. That is, the multidecadal variations in the greenhouse gas concentrations and anthropogenic/volcanic aerosols make positive and negative contributions, respectively. Our new finding is conducive to EASAT predictions in the following decades due to the predictability of AMO and anthropogenic forcings. Plain Language Summary: Internal variability is one of the most important sources of uncertainty in predicting the East Asian winter temperature in future decades. It is thus essential to address associated reasons for the internally generated East Asian temperature variability. This study tries to separate internal variability from the externally forced climate response for the winter East Asian averaged surface air temperature (EASAT) based on three observational datasets and large ensemble simulations from 12 latest coupled models. We find that the internal variability explains 59% of the total EASAT multidecadal variations, in which the Atlantic Multidecadal Oscillation (AMO) plays a vital role. The external forcings play the secondary role. This means that accurate prediction of the AMO would be helpful for predicting internally generated EASAT variations at the multidecadal scale. Key Points: Internal variability has played a dominant role in the multidecadal variations of winter temperature averaged over East Asia since 1880The Atlantic Multidecadal Oscillation plays a vital role in internally generated East Asian winter temperature variationsChanges in greenhouse gas concentrations and anthropogenic/volcanic aerosols make positive and negative contributions, respectively [ABSTRACT FROM AUTHOR]
- Published
- 2022
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