{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:49:31Z","timestamp":1760240971478,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2019,11,13]],"date-time":"2019-11-13T00:00:00Z","timestamp":1573603200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The airborne Hurricane Imaging Radiometer (HIRAD) was developed to remotely sense hurricane surface wind speed (WS) and rain rate (RR) from a high-altitude aircraft. The approach was to obtain simultaneous brightness temperature measurements over a wide frequency range to independently retrieve the WS and RR. In the absence of rain, the WS retrieval has been robust; however, for moderate to high rain rates, the joint WS\/RR retrieval has not been successful. The objective of this paper was to resolve this issue by developing an improved forward radiative transfer model (RTM) for the HIRAD cross-track viewing geometry, with separated upwelling and specularly reflected downwelling atmospheric paths. Furthermore, this paper presents empirical results from an unplanned opportunity that occurred when HIRAD measured brightness temperatures over an intense tropical squall line, which was simultaneously observed by a ground based NEXRAD (Next Generation Weather Radar) radar. The independently derived NEXRAD RR created the simultaneous 3D rain field \u201csurface truth\u201d, which was used as an input to the RTM to generate HIRAD modeled brightness temperatures. This paper presents favorable results of comparisons of theoretical and the simultaneous, collocated HIRAD brightness temperature measurements that validate the accuracy of this new HIRAD RTM.<\/jats:p>","DOI":"10.3390\/rs11222650","type":"journal-article","created":{"date-parts":[[2019,11,13]],"date-time":"2019-11-13T09:11:27Z","timestamp":1573636287000},"page":"2650","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Validation of the Hurricane Imaging Radiometer Forward Radiative Transfer Model for a Convective Rain Event"],"prefix":"10.3390","volume":"11","author":[{"given":"Abdusalam","family":"Alasgah","sequence":"first","affiliation":[{"name":"King Abdulaziz City for Science and Technology, Riyadh 12354, Saudi Arabia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0662-0716","authenticated-orcid":false,"given":"Maria","family":"Jacob","sequence":"additional","affiliation":[{"name":"Facultad de Matem\u00e1tica, Astronom\u00eda y F\u00edsica, Universidad Nacional de C\u00f3rdoba; C\u00f3rdoba X5000, Argentina"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8796-4598","authenticated-orcid":false,"given":"Linwood","family":"Jones","sequence":"additional","affiliation":[{"name":"Central Florida Remote Sensing Lab, University of Central Florida, Orlando, FL 32816-2362, USA"}]},{"given":"Larry","family":"Schneider","sequence":"additional","affiliation":[{"name":"Central Florida Remote Sensing Lab, University of Central Florida, Orlando, FL 32816-2362, USA"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1109\/TGRS.2011.2161637","article-title":"Hurricane Wind Speed Measurements in Rainy Conditions using the Airborne Hurricane Imaging Radiometer (HIRAD)","volume":"50","author":"Amarin","year":"2012","journal-title":"IEEE Trans. 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Lett."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/22\/2650\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:34:05Z","timestamp":1760189645000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/22\/2650"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,13]]},"references-count":20,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2019,11]]}},"alternative-id":["rs11222650"],"URL":"https:\/\/doi.org\/10.3390\/rs11222650","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2019,11,13]]}}}