Fig. 1: Tropical cyclones and sustained salinity freshening.
From: Sustained freshening of Arabian Sea High Salinity Water induced by extreme precipitation events
Tracks of tropical cyclones during a 2014–2018 and b 2019–2023, with pre-monsoon (May–June) cyclones marked by black symbols and post-monsoon (September–December) cyclones marked by red symbols. The legend columns represent the year (first column), season (pre-monsoon = 1, post-monsoon = 2) in the second column, and cyclone intensity (0—cyclone, 1—severe, 2—extremely severe, 3—super cyclone) in the last column. Cyclones are categorized by wind speeds, with extreme cyclones defined as those exceeding 46 m s−1. During the total period, 20 cyclones were observed: 6 (30%) during the pre-monsoon and 14 (70%) during the post-monsoon, indicating an increase in post-monsoon cyclones. The number of cyclones north of 15°N increased during 2019–2023. c, d show the annual mean differences between 2019–2023 and 2014–2018 for c rainfall (mm d−1) and d salinity (psu) in the upper 50 m. Rainfall data are from the Integrated Multi-satellite Retrievals for GPM (IMERG46), and salinity data are from the EN4 dataset based on Argo profiles45. Positive values represent excess rainfall, while negative salinity values indicate freshening during 2019–2023 compared to 2014–2018.
