###### Abstract  
The relationship between the microwave scattering coefficient from the sea surface and wind field has been extensively studied. Nevertheless, recent research on air-sea coupling has shown that sea-air temperature difference (_SATD_) also significantly affects the scattering coefficient. Therefore, to reveal the influence of different environmental parameters, such as salinity, sea surface temperature (_SST_), and _SATD_ on the scattering coefficient, a theoretical analysis has been carried out firstly. Meanwhile, the coupling coefficient between a scattering coefficient anomaly (_SCA_) and sea-air temperature difference anomaly (_SATDA_) over four typical sea regions is compared with that between an _SCA_ and sea surface temperature anomaly (_SSTA_) by using the nearly 7-year data of the ECMWF, AMSR-E, and QSCAT. The results demonstrate that _SCA_ is more sensitive to _SATDA_ than _SSTA_. The values of \(k_{sadda}\) between the _SATDA_ and _SCA_ exhibit seasonal variation, being higher in summer and lower in winter. Specifically, \(k_{sadda}\) can reach a maximum of 0.62 in summer and drops to 0.2 in winter. Furthermore, the effects of the regional monthly mean sea surface temperature (_RMMSST_), regional monthly mean air temperature (_RMMMAT_), regional monthly mean sea-air temperature difference (_RMMSATD_), and regional monthly mean wind speed (_RMMWS_) on \(k_{sadda}\) are also discussed in detail. It is found that the _RMMSATD_ is a crucial factor influencing \(k_{sadda}\). And the negative correlation coefficient between the _RMMSATD_ and \(k_{sadda}\) is -0.81.  
sea surface temperature; sea-air temperature difference; scattering coefficient; coupling coefficient 2025  
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stability of the marine atmospheric boundary layer [18; 19]. Based on these findings, [PERSON] analyzed the responsive relationship between the wind speed and \(SST\) retrieved by a QuikSCAT scatterometer and a TRMM imager, respectively. [PERSON] found that there was a positive correlation between wind speed and \(SST\) in the typical mesoscale regions [20]. In 2005, [PERSON] investigated the impact of \(SST\) on the atmospheric boundary layer in the Agulhas Current region, and the results showed that the wind speed anomaly was positively correlated with the \(SSTA\)[21]. [PERSON]'s similarity theory is an important theoretical framework to describe the ocean-atmosphere interaction, which reveals the effect of an \(SATD\) on the equivalent neutral wind speed (\(ENWS\)) [22]. In ref. [23], [PERSON] investigated the coupling relationship between an equivalent neutral wind speed anomaly (\(ENWS\)) and \(SATDA\) by using satellite data. It was found that the coupling coefficient between an \(ENWS\) and \(SATDA\) shows a regular seasonal change of being higher in summer and lower in winter. [PERSON] further explored the regional and seasonal dependence of atmospheric responses to mesoscale sea surface temperature perturbations, focusing on the coupling relationship between a wind speed above the sea surface and the \(SST\) in the Agulhas Return Current and Kuroshio Extension regions. The results showed that wind stress exhibits a positive correlation with \(SST\) within mesoscale ranges [24]. In recent research, a correlation between the \(ENWS\) and \(SATDA\) was revealed by [PERSON]. And the results over four typical sea regions indicated that the \(ENWS\) is more sensitive to the \(SATDA\) than the \(SSTA\)[25]. The studies on air-sea coupling in [18; 19; 20; 21; 22; 23; 24; 25] show that the \(SST\) and \(SATD\) have significant effects on the wind speed above the sea surface. Therefore, it seems reasonable that the air-sea coupling effect would also affect the sea surface electromagnetic scattering coefficient since the sea surface wind field is the most important parameter in the scattering models.