{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,7]],"date-time":"2026-06-07T04:15:01Z","timestamp":1780805701935,"version":"3.54.1"},"reference-count":56,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,5,24]],"date-time":"2022-05-24T00:00:00Z","timestamp":1653350400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["776848"],"award-info":[{"award-number":["776848"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The pressing need for accurate and reliable precipitation measurements and forecasting poses theoretical and technological problems. Remote-sensing instruments with increased coverage and sensitivity (such as space-borne and ground-based radar) are available; however, their full exploitation requires physical calibration and validation based on a deep knowledge of precipitation microphysics. This study reports a detailed analysis of the evidence of non-terminal velocities in a mid-latitude (Bologna, Italy) and a tropical location (Kolkata, India). The data from two identical disdrometers OTT-Parsivel2 were analyzed to shed light on the nature of the raindrops that fall at a velocity that is significantly higher (i.e., super-terminal drops) or lower (sub-terminal drops) than the terminal velocity expected for the raindrop sizes. The results show a significant fraction of super- and sub-terminal drops in both locations. The percentages of both super- and sub-terminal drops were higher in Kolkata. However, the difference was more notable for convective rain. The percentages of both super- and sub-terminal drops were found to be high within a drop diameter of 1 mm. The number of sub-terminal drops seemed to increase with an increase in diameter for drops larger than ~2.5 mm. The natural rain in Bologna showed stronger evidence of drop break-up in correspondence with the evolution of non-terminal velocities. Moreover, this study once again pointed toward the fact that the process of break-up cannot be neglected in natural rain of tropical or mid-latitude locations. We found that 7% and 10% of rain samples in Bologna and Kolkata seemed to be subjected to drop break-up. The results indicate that radar measurements of rain in the tropics or mid-latitude regions, relying on the Gunn\u2013Kinzer relationship between velocity and diameter, should be verified by observations of disdrometers for a high precision QPE.<\/jats:p>","DOI":"10.3390\/rs14112515","type":"journal-article","created":{"date-parts":[[2022,5,25]],"date-time":"2022-05-25T00:14:14Z","timestamp":1653437654000},"page":"2515","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["An Investigation on Super- and Sub-Terminal Drops in Two Different Rain Categories and Climate Regimes"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4180-1694","authenticated-orcid":false,"given":"Chandrani","family":"Chatterjee","sequence":"first","affiliation":[{"name":"Department of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology, Indore 452020, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1283-7679","authenticated-orcid":false,"given":"Federico","family":"Porc\u00f9","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy \u201cAugusto Righi\u201d, Alma Mater Studiorum University of Bologna, 40127 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4373-1631","authenticated-orcid":false,"given":"Saurabh","family":"Das","sequence":"additional","affiliation":[{"name":"Department of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology, Indore 452020, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7047-6213","authenticated-orcid":false,"given":"Alessandro","family":"Bracci","sequence":"additional","affiliation":[{"name":"Department of Physics and Astronomy \u201cAugusto Righi\u201d, Alma Mater Studiorum University of Bologna, 40127 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e2020GL091950","DOI":"10.1029\/2020GL091950","article-title":"Characterizing uncertainties in ground \u201ctruth\u201d of precipitation over complex terrain through high-resolution numerical modeling","volume":"48","author":"Ouyang","year":"2021","journal-title":"Geophys. 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