Spatiotemporal characteristics of actual evapotranspiration in Northeast China and its influencing factors

The spatiotemporal characteristics of actual evapotranspiration (ETa) in Northeast China from 2003 to 2020 was analyzed in this research using the global SSEBOP ETa product. Then simple correlation coefficient and sensitivity coefficient were adopted to quantify correlation relationship and the sensitivity of ETa to the influencing factors such as air temperature (T), precipitation (P), surface net radiation (RN), surface wind speed (WS), actual vapor pressure (EA), and normalized difference vegetation index (NDVI), et al. The result showed that ETa showed obvious seasonal characteristics, with the highest ETa in summer. Meteorological factors and land use characteristics jointly affect regional ETa. In summer, land use types played a dominant role. The WS, EA, P, and NDVI were mainly positively correlated with ETa. The RN and T were mainly negatively correlated with ETa. As time goes on, the ETa will be more sensitive to RN, P and NDVI, but be less sensitive to T, EA and WS.