Variation And Mechanism Analysis Of Polar Warming Amplification Effect In Different Warming Scenarios Of CMIP6

The climate in polar regions has experienced an obvious warming amplification due to global warming,resulting in the rapid melting of sea ice in Arctic and Antarctic,which has an impact on the surrounding ecosystem,the atmospheric circulation at middle and low latitudes and the occurrence of extreme climate events.In this study,the changes in polar amplification are analyzed in response to feedback mechanisms(including Planck,lapse rate,cloud,water vapor,albedo feedback,CO₂ radiative forcing,ocean heat uptake,and atmospheric heat transport)under three warming scenarios in CMIP6—namely,SSP1-2.6,SSP2-4.5,and SSP5-8.5 compared with historical scenario.The main conclusions are as follows:(1)Since the industrial revolution,with the passage of time,the surface temperature has increased significantly,especially in the Arctic.The temperature increase in the Antarctic was slightly less significant,but it was still more significant than that in the tropical region,which can be collectively called the polar amplification.(2)The most important factor of Arctic amplification was lapse rate feedback,followed by albedo feedback,Planck feedback and weak atmospheric heat transport.The dominant factor of Antarctic amplification was also lapse rate feedback,followed by albedo feedback,atmospheric heat transport and Planck feedback.In both Arctic and Antarctic regions,winter warming was stronger than summer warming,which was mainly dominated by ocean heat uptake.The second most important mechanism was lapse rate feedback.(3)The Arctic amplification was stronger than the Antarctic amplification,which was mainly dominated by lapse rate feedback,followed by Planck feedback and albedo feedback.In both winter and summer,the Arctic amplification was stronger than the Antarctic amplification.In winter,the lapse rate feedback played the most important role,followed by ocean heat uptake and CO₂ radiative forcing.In summer,cloud feedback played the most important role,followed by Planck feedback and albedo feedback.(4)The Arctic amplification decreased significantly with surface warming,and the dominant feedback mechanisms were Planck feedback,lapse rate feedback and albedo feedback.The variation of the Antarctic amplification was very small and was ignored here.The diversity of the models of the warming contribution in the Arctic was mainly drived by the lapse rate feedback,Planck feedback and albedo feedback,which helped reduce the diversity of the models.