Global increase in tropical cyclone rain rate

• Published in: Nature communications Vol. 12; no. 1; p. 5344
• Main Authors: Guzman, Oscar, Jiang, Haiyan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.09.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 704/106/35/823; 704/106/694/1108; Cyclones; Humanities and Social Sciences; multidisciplinary; Rainfall; Rainfall rate; Science; Science (multidisciplinary); Sea surface temperature; Trends; Tropical cyclones
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-25685-2

Theoretical models of the potential intensity of tropical cyclones (TCs) suggest that TC rainfall rates should increase in a warmer environment but limited observational evidence has been studied to test these hypotheses on a global scale. The present study explores the general trends of TC rainfall rates based on a 19-year (1998–2016) time series of continuous observational data collected by the Tropical Rainfall Measuring Mission and the Global Precipitation Measurement mission. Overall, observations exhibit an increasing trend in the average TC rainfall rate of about 1.3% per year, a fact that is contributed mainly by the combined effect of the reduction in the inner-core rainfall rate with the increase in rainfall rate on the rainband region. We found that the increasing trend is more pronounced in the Northwestern Pacific and North Atlantic than in other global basins, and it is relatively uniform for all TC intensities. Further analysis shows that these trends are associated with increases in sea surface temperature and total precipitable water in the TC environment. How much the potential intensity of tropical cyclones (TCs) increases in warmer environments is not well known. Here, the authors show that TC rainfall rates have increased by 1.3% per year between 1998 and 2018, a trend that is mainly driven by stronger rainfall in the outer-core region of TCs.