{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T00:08:50Z","timestamp":1774570130526,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2019,7,10]],"date-time":"2019-07-10T00:00:00Z","timestamp":1562716800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["BE1780\/31-1 and BE1780\/38-1"],"award-info":[{"award-number":["BE1780\/31-1 and BE1780\/38-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Research Office of the University of Cuenca (DIUC) and ETAPA","award":["Project \u201cIdentificaci\u00f3n de los procesos hidrometeorol\u00f3gicos que desencadenan crecidas a partir de la informaci\u00f3n suministrada por un radar de precipitaci\u00f3n\u201d and the project \u201cDesarrollo de modelos para pron\u00f3stico hidrol\u00f3gico a partir de datos de radar mete"],"award-info":[{"award-number":["Project \u201cIdentificaci\u00f3n de los procesos hidrometeorol\u00f3gicos que desencadenan crecidas a partir de la informaci\u00f3n suministrada por un radar de precipitaci\u00f3n\u201d and the project \u201cDesarrollo de modelos para pron\u00f3stico hidrol\u00f3gico a partir de datos de radar mete"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Despite many efforts of the radar community, quantitative precipitation estimation (QPE) from weather radar data remains a challenging topic. The high resolution of X-band radar imagery in space and time comes with an intricate correction process of reflectivity. The steep and high mountain topography of the Andes enhances its complexity. This study aims to optimize the rainfall derivation of the highest X-band radar in the world (4450 m a.s.l.) by using a random forest (RF) model and single Plan Position Indicator (PPI) scans. The performance of the RF model was evaluated in comparison with the traditional step-wise approach by using both, the Marshall-Palmer and a site-specific Z\u2013R relationship. Since rain gauge networks are frequently unevenly distributed and hardly available at real time in mountain regions, bias adjustment was neglected. Results showed an improvement in the step-wise approach by using the site-specific (instead of the Marshall-Palmer) Z\u2013R relationship. However, both models highly underestimate the rainfall rate (correlation coefficient &lt; 0.69; slope up to 12). Contrary, the RF model greatly outperformed the step-wise approach in all testing locations and on different rainfall events (correlation coefficient up to 0.83; slope = 1.04). The results are promising and unveil a different approach to overcome the high attenuation issues inherent to X-band radars.<\/jats:p>","DOI":"10.3390\/rs11141632","type":"journal-article","created":{"date-parts":[[2019,7,10]],"date-time":"2019-07-10T11:56:51Z","timestamp":1562759811000},"page":"1632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Optimization of X-Band Radar Rainfall Retrieval in the Southern Andes of Ecuador Using a Random Forest Model"],"prefix":"10.3390","volume":"11","author":[{"given":"Johanna","family":"Orellana-Alvear","sequence":"first","affiliation":[{"name":"Laboratory for Climatology and Remote Sensing (LCRS), Faculty of Geography, University of Marburg, D-35032 Marburg, Germany"},{"name":"Departamento de Recursos H\u00eddricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca EC010207, Ecuador"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7683-3768","authenticated-orcid":false,"given":"Rolando","family":"C\u00e9lleri","sequence":"additional","affiliation":[{"name":"Departamento de Recursos H\u00eddricos y Ciencias Ambientales, Universidad de Cuenca, Cuenca EC010207, Ecuador"},{"name":"Facultad de Ingenier\u00eda, Universidad de Cuenca, Cuenca EC010207, Ecuador"}]},{"given":"R\u00fctger","family":"Rollenbeck","sequence":"additional","affiliation":[{"name":"Laboratory for Climatology and Remote Sensing (LCRS), Faculty of Geography, University of Marburg, D-35032 Marburg, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6559-2033","authenticated-orcid":false,"given":"J\u00f6rg","family":"Bendix","sequence":"additional","affiliation":[{"name":"Laboratory for Climatology and Remote Sensing (LCRS), Faculty of Geography, University of Marburg, D-35032 Marburg, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3065","DOI":"10.1175\/JAMC-D-17-0009.1","article-title":"Analysis of Rain Types and Their Z\u2013R Relationships at Different Locations in the High Andes of Southern Ecuador","volume":"56","author":"Rollenbeck","year":"2017","journal-title":"J. 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