{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T17:35:00Z","timestamp":1777484100268,"version":"3.51.4"},"reference-count":31,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,3,14]],"date-time":"2020-03-14T00:00:00Z","timestamp":1584144000000},"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>Seasonal changes control the development of salt crust over the Salar de Aguas Calientes Sur located in Andes Highlands, Chile. Precipitations throughout the Altiplanic winter (December to March) and austral winter (June to September) caused ponds to enlarge and surface salt crusts to dissolve driving roughness and dielectric features of the salar surface change over time. A four-year time series backscattering coefficient analysis, obtained by Sentinel 1 and ALOS-2\/PALSAR-2 with 10 m of spatial resolution, demonstrated the capability of microwaves to discriminate seasonal patterns illustrated in this paper. Both sensors showed to be sensitive to changes in the surface crust due to weather conditions. Backscattered power gradually increased during the driest months as the rough salt crusts develop and decreased rapidly due to precipitations or flooding events, which lead to a smoothing appearance to radar. The high temporal frequency of acquisition in Sentinel 1 (5\u201313 scenes\/month) allowed the discrimination among climate and annual seasonality and episodic events in the C-band backscatter coefficient. On the other hand, ALOS-2\/PALSAR-2 showed subsurface changes at L-band since the salinity of the brine in the soil reduces the penetration depth of backscattered power for shorter wavelengths. Results might be useful to monitor salars with geographic and weather conditions similar to Salar de Aguas Calientes Sur.<\/jats:p>","DOI":"10.3390\/rs12060941","type":"journal-article","created":{"date-parts":[[2020,3,18]],"date-time":"2020-03-18T08:20:44Z","timestamp":1584519644000},"page":"941","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Seasonality Analysis of Sentinel-1 and ALOS-2\/PALSAR-2 Backscattered Power over Salar de Aguas Calientes Sur, Chile"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4311-5812","authenticated-orcid":false,"given":"Analia","family":"Delsouc","sequence":"first","affiliation":[{"name":"Mag\u00edster en Teledetecci\u00f3n, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mat\u00edas","family":"Barber","sequence":"additional","affiliation":[{"name":"Grupo de Teledetecci\u00f3n Cuantitativa, Instituto de Astronom\u00eda y F\u00edsica del Espacio (IAFE, CONICET-UBA), Buenos Aires 1428, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3206-9999","authenticated-orcid":false,"given":"Audrey","family":"Gallaud","sequence":"additional","affiliation":[{"name":"Subgerencia de Recursos Naturales, Centro de Informaci\u00f3n de Recursos Naturales (CIREN), Santiago 7501556, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francisco","family":"Grings","sequence":"additional","affiliation":[{"name":"Grupo de Teledetecci\u00f3n Cuantitativa, Instituto de Astronom\u00eda y F\u00edsica del Espacio (IAFE, CONICET-UBA), Buenos Aires 1428, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1836-5684","authenticated-orcid":false,"given":"Paulina","family":"Vidal-P\u00e1ez","sequence":"additional","affiliation":[{"name":"Mag\u00edster en Teledetecci\u00f3n, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"},{"name":"H\u00e9mera Centro de Observaci\u00f3n de la Tierra, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3670-6190","authenticated-orcid":false,"given":"Waldo","family":"P\u00e9rez-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Mag\u00edster en Teledetecci\u00f3n, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"},{"name":"H\u00e9mera Centro de Observaci\u00f3n de la Tierra, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Idania","family":"Brice\u00f1o-De-Urbaneja","sequence":"additional","affiliation":[{"name":"Mag\u00edster en Teledetecci\u00f3n, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"},{"name":"H\u00e9mera Centro de Observaci\u00f3n de la Tierra, Escuela de Ingenier\u00eda Forestal, Facultad de Ciencias, Universidad Mayor, Santiago 8340589, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1007\/BFb0045179","article-title":"The Cenozoic Saline Deposits of the Chilean Andes Between 18\u00b000\u2019 and 27\u00b000\u2019 South Latitude","volume":"17","year":"1988","journal-title":"Lect. 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