**5. Summaries**

The wind-driven UEH is a typical seasonal coastal upwelling in the northwestern SCS. Satellite SST data and wind products help to investigate the variability of UEH to multi-scale atmospheric processes. This chapter overviews the recent progress, including the long-term and interannual variability of UEH with the global climate change in recent decades, the response of UEH and UEV to super El Niño events in 1998 and 2016, the variation of UEH after sudden impacts of typhoon passages, and the variability mechanisms. The main results are summarized as follows:

