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Recent study shows that the asymmetric component (AC) of Hadley circulation variability during late winter and early spring can be explained by the combined effect between background sea surface temperature (SST) and the SST anomalies associated with El Nino-Southern Oscillation (ENSO). But the sensitivity of AC-ENSO relationship to background SST and ENSO properties is still unknown. Using 17 climate models from the Coupled Model Intercomparison Project phase 5, we investigated the sensitivity of the AC-ENSO relationship to the background SST and three ENSO properties. Most of the Coupled Model Intercomparison Project phase 5 models capture the spatial structure of the AC and reproduce the AC-ENSO relationship, but the AC-ENSO relationship has large intermodel spread. The AC-ENSO relationship is mostly sensitive to ENSO zonal extent. ENSO amplitude can also influence the AC-ENSO relationship by affecting the zonal extent. However, ENSO meridional extent and background SSTabove a certain thresholdhave little influence on the AC-ENSO relationship.

Plain Language Summary El Nino-Southern Oscillation (ENSO) has robust impacts on Hadley circulation (HC). The HC is one of the most important large-scale atmospheric circulations that can affect precipitation and drought in the tropics and subtropics. It is reported that the background sea surface temperature (SST) over the South Pacific Convergence Zone can modulate the relationship between the HC and ENSO. We know that both the background SST and ENSO pattern may change in response to global warming. Therefore, it is necessary to determine how the relationship between HC and ENSO depends on the background SST and ENSO patterns. In this study, we estimated the sensitivity of the HC-ENSO relationship to the background SST and ENSO properties in the state-of-the-art coupled climate models, which promotes our understanding about how the simulation biases of the climatological SST and ENSO properties in these climate models influence the HC-ENSO relationship and to what degree ENSO events may impact the HC in a warming world.