{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T19:28:59Z","timestamp":1768418939930,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,9]],"date-time":"2021-02-09T00:00:00Z","timestamp":1612828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010067","name":"Gobierno de Arag\u00f3n","doi-asserted-by":"publisher","award":["DGA-FSE  T20_17R"],"award-info":[{"award-number":["DGA-FSE  T20_17R"]}],"id":[{"id":"10.13039\/501100010067","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Snow makes a great contribution to the hydrological cycle in cold regions. The parameter to characterize available the water from the snow cover is the well-known snow water equivalent (SWE). This paper presents a near-surface-based radar for determining the SWE from the measured complex spectral reflectance of the snowpack. The method is based in a stepped-frequency continuous wave radar (SFCW), implemented in a coherent software defined radio (SDR), in the range from 150 MHz to 6 GHz. An electromagnetic model to solve the electromagnetic reflectance of a snowpack, including the frequency and wetness dependence of the complex relative dielectric permittivity of snow layers, is shown. Using the previous model, an approximated method to calculate the SWE is proposed. The results are presented and compared with those provided by a cosmic-ray neutron SWE gauge over the 2019\u20132020 winter in the experimental AEMet Formigal-Sarrios test site. This experimental field is located in the Spanish Pyrenees at an elevation of 1800 m a.s.l. The results suggest the viability of the approximate method. Finally, the feasibility of an auxiliary snow height measurement sensor based on a 120 GHz frequency modulated continuous wave (FMCW) radar sensor, is shown.<\/jats:p>","DOI":"10.3390\/rs13040616","type":"journal-article","created":{"date-parts":[[2021,2,10]],"date-time":"2021-02-10T04:33:46Z","timestamp":1612931626000},"page":"616","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Analysis of the Snow Water Equivalent at the AEMet-Formigal Field Laboratory (Spanish Pyrenees) During the 2019\/2020 Winter Season Using a Stepped-Frequency Continuous Wave Radar (SFCW)"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0775-4641","authenticated-orcid":false,"given":"Rafael","family":"Alonso","sequence":"first","affiliation":[{"name":"Department of Applied Physics, University of Zaragoza, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6531-5810","authenticated-orcid":false,"given":"Jos\u00e9 Mar\u00eda Garc\u00eda del","family":"Pozo","sequence":"additional","affiliation":[{"name":"Department of Applied Physics, University of Zaragoza, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9551-9918","authenticated-orcid":false,"given":"Samuel T.","family":"Buis\u00e1n","sequence":"additional","affiliation":[{"name":"Infrastructure Division of the Aragon Regional Office of the Spanish State Meteorological Agency (AEMet), Paseo del Canal, 17, 50007 Zaragoza, Spain"}]},{"given":"Jos\u00e9 Adolfo","family":"\u00c1lvarez","sequence":"additional","affiliation":[{"name":"Ebro River Basin Authority (CHE), Paseo de Sagasta, 24-26, 50008 Zaragoza, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"521","DOI":"10.1175\/JHM-D-11-072.1","article-title":"Complexity of snow schemes in a climate model and its impact on Surface energy and hydrology","volume":"13","author":"Dutra","year":"2012","journal-title":"J. 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