Satisfactory simulation of negative shortwave(SW) radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes...Satisfactory simulation of negative shortwave(SW) radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes in the atmospheric and/or oceanic model, but the coupling process in coupled models has not received much attention. To investigate the coupling effect on SW feedback, two versions of an AGCM and their corresponding coupled models are analyzed. Results indicate that the effects of the coupling process in the two versions lead to weakening and enhancement of the negative feedback in the earlier and new versions, respectively, mainly due to their different changes in cloud fraction feedback and dynamical feedback. Further examination of the nonlinearity of the feedback reveals that the opposite coupling effects in the two versions originate from their different responses to El Nio and to La Nia.展开更多
基金supported by the National Basic Research Program of China[973 Program,grant number 2015CB954102]the National Natural Sciences Foundation of China[grant number41205079]the China Postdoctoral Science Foundation[grant number 2016M591234]
文摘Satisfactory simulation of negative shortwave(SW) radiative feedback during ENSO in the equatorial Pacific remains a challenging issue for climate models. Previous studies have focused on specific physical processes in the atmospheric and/or oceanic model, but the coupling process in coupled models has not received much attention. To investigate the coupling effect on SW feedback, two versions of an AGCM and their corresponding coupled models are analyzed. Results indicate that the effects of the coupling process in the two versions lead to weakening and enhancement of the negative feedback in the earlier and new versions, respectively, mainly due to their different changes in cloud fraction feedback and dynamical feedback. Further examination of the nonlinearity of the feedback reveals that the opposite coupling effects in the two versions originate from their different responses to El Nio and to La Nia.