Observing storm surges in China's coastal areas by integrating multi-source satellite altimeters

Abstract Storm surge is one of the most dangerous and destructive natural disasters in the world, which is a serious threat to the survival and development of human beings in coastal areas. Therefore, in order to mitigate damage and loss, it is necessary to enhance our capabilities of observing, understanding and forecasting storm surges. In this study, we used 25-year (1993–2017) of multi-source satellite altimeters and coastal tide-gauge data to monitor storm surges in China's coastal regions. We then found that satellite altimetry can be used as a useful complementary dataset to study storm surges. During the above study period, the multi-source satellite altimeters captured 32 storm surge events, accounting for nearly 26% of storm surge events were identified from tide gauges in this study area. Although coastal surge heights identified by tide gauges is significantly higher than those recorded by satellite altimeters at most tide gauges, coastal surge heights captured by satellite altimeters can reflect the transient spatial and temporal dynamic surge process. Simultaneously, this study also shows that the altimetry mission to capture storm surges is of an opportunistic nature, and the presence of multiple satellite tracks in a region greatly enhances the probability of capturing signals of extreme events. Though satellite altimeters have been proven to be a complementary means of observing storm surges, effective strategies will be required for regular monitoring of storm surges in the future. In addition, storm surge is also affected by global climate change and rising sea levels. Therefore, we can use wide-swath altimetry or joint multi-mission gridded altimeter products and reanalysis dataset to monitor storm surges in the future.