Affiliation:
1. National Marine Environmental Forecasting Center, Beijing 100081, China
2. Key Laboratory of Marine Hazards Forcasting MNR, Beijing 100081, China
3. Tianjin Key Laboratory for Marine Environmental Research and Service, School of Marine Science and Technology, Tianjin University, Tianjin 300072, China
Abstract
Marine heatwaves (MHWs) are changing global ecosystems and bearing profound socio-economic impacts, yet our understanding of the spatial features, temporal evolution characteristics, and regional differences in China’s marginal seas remains insufficient. In this study, the spatio-temporal variation characteristics of the frequency, mean intensity, maximum intensity, cumulative intensity, duration and total days of MHWs are systematically analyzed based on daily sea surface temperature data from Operational Sea Surface Temperature and Ice Analysis (OSTIA) for the period of 1983–2020. The results show the following: The annual mean frequency of MHWs in China’s coastal seas is 1.4–4.6 counts per year and increases gradually from north to south. The annual mean of mean intensity, maximum intensity and cumulative intensity are, respectively, in the ranges of 0.3–2.9 °C, 0.4–3.7 °C and 3.9–41.7 °C days, all of which show a significant decreasing trend from north to south. The annual mean of duration and total days of MHWs are in the respective ranges 8.7–19.7 and 18.9–69.1 days. The annual mean of frequency, cumulative intensity, duration and total days all show a clear increasing trend, with respective linear increases of 1.03 counts, 3.57 °C days, and 1.98 and 17.58 days per decade. The annual means of the mean intensity and maximum intensity have no obvious upward trend, with the exceptions of the Bohai and Yellow Seas. Finally, MHWs were divided into the four categories of moderate, strong, severe and extreme, with the results showing that moderate ones account for more than 70% of all heatwave events, while strong, severe and extreme ones, respectively, account for about 25%, 2% and 0.02%.
Funder
development and application demonstration of regional high-resolution and ultra-high-resolution nested marine multi-source data assimilation system around islands and reefs
National Natural Science Foundation of China
Ocean Telemetry Technology Innovation Center, Ministry of Natural Resources
Subject
Atmospheric Science,Environmental Science (miscellaneous)
Reference23 articles.
1. Marine heatwaves threaten global bio-diversity and the provision of ecosystem services;Smale;Nat. Clim. Chang.,2019
2. A hierarchical approach to defining marine heatwaves;Hobday;Prog. Oceanogr.,2016
3. Longer and more frequent marine heatwaves over the past century;Oliver;Nat. Commun.,2018
4. IPCC (2021, August 09). Climate Change 2021: The Physical Science Basis [M/OL]. Available online: https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter_07.pdf.
5. Marine heatwaves under global warming;Fischer;Nature,2018