Variation and possible causes of Marine Heatwaves under global warming condition

Abstract

Under a warming climate, extreme ocean warming events, namely Marine Heatwaves (MHW), have become more frequent and stronger in global ocean regions. This study examines how the long-term variability of global marine heatwave characteristics is affected by global warming. We quantify the long-term trends (1982-2022) of MHW and investigate the connection between mean climate change and MHW trends. Since 1982, MHW properties over most global regions have increased positive signals during winter and summer. We investigate the rapidly variation of marine heatwave duration and intensity over the global ocean regions compared to the global average change. In addition, this study reveals the possible atmospheric and oceanic processes driving these rapidly changes in ocean areas where MHW occurs dramatically increasing. For example, during winter, the MHW has increased rapidly over the northern East Sea region (over 600 %) compared to the past two decades and this region is influenced on the northward shift of warm ocean current.