{"id":"https://openalex.org/W1991893068","doi":"https://doi.org/10.1109/tgrs.2011.2177667","title":"ASCAT Surface State Flag (SSF): Extracting Information on Surface Freeze/Thaw Conditions From Backscatter Data Using an Empirical Threshold-Analysis Algorithm","display_name":"ASCAT Surface State Flag (SSF): Extracting Information on Surface Freeze/Thaw Conditions From Backscatter Data Using an Empirical Threshold-Analysis Algorithm","publication_year":2012,"publication_date":"2012-01-17","ids":{"openalex":"https://openalex.org/W1991893068","doi":"https://doi.org/10.1109/tgrs.2011.2177667","mag":"1991893068"},"language":"en","primary_location":{"id":"doi:10.1109/tgrs.2011.2177667","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tgrs.2011.2177667","pdf_url":null,"source":{"id":"https://openalex.org/S111326731","display_name":"IEEE Transactions on Geoscience and Remote Sensing","issn_l":"0196-2892","issn":["0196-2892","1558-0644"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Transactions on Geoscience and Remote Sensing","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5052213658","display_name":"Vahid Naeimi","orcid":null},"institutions":[{"id":"https://openalex.org/I145847075","display_name":"TU Wien","ror":"https://ror.org/04d836q62","country_code":"AT","type":"education","lineage":["https://openalex.org/I145847075"]},{"id":"https://openalex.org/I2898391981","display_name":"Deutsches Zentrum f\u00fcr Luft- und Raumfahrt e. V. (DLR)","ror":"https://ror.org/04bwf3e34","country_code":"DE","type":"facility","lineage":["https://openalex.org/I1305996414","https://openalex.org/I2898391981"]}],"countries":["AT","DE"],"is_corresponding":true,"raw_author_name":"Vahid Naeimi","raw_affiliation_strings":["German Remote Sensing Data Center (DFD), German AeroSpace Center (DLR), Wessling, Germany","Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria"],"affiliations":[{"raw_affiliation_string":"German Remote Sensing Data Center (DFD), German AeroSpace Center (DLR), Wessling, Germany","institution_ids":["https://openalex.org/I2898391981"]},{"raw_affiliation_string":"Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria","institution_ids":["https://openalex.org/I145847075"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5015111226","display_name":"Christoph Paulik","orcid":"https://orcid.org/0000-0002-4231-7933"},"institutions":[{"id":"https://openalex.org/I145847075","display_name":"TU Wien","ror":"https://ror.org/04d836q62","country_code":"AT","type":"education","lineage":["https://openalex.org/I145847075"]}],"countries":["AT"],"is_corresponding":false,"raw_author_name":"Christoph Paulik","raw_affiliation_strings":["Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria"],"affiliations":[{"raw_affiliation_string":"Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria","institution_ids":["https://openalex.org/I145847075"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5076659280","display_name":"Annett Bartsch","orcid":"https://orcid.org/0000-0002-3737-7931"},"institutions":[{"id":"https://openalex.org/I145847075","display_name":"TU Wien","ror":"https://ror.org/04d836q62","country_code":"AT","type":"education","lineage":["https://openalex.org/I145847075"]}],"countries":["AT"],"is_corresponding":false,"raw_author_name":"Annett Bartsch","raw_affiliation_strings":["Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria"],"affiliations":[{"raw_affiliation_string":"Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria","institution_ids":["https://openalex.org/I145847075"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5066754586","display_name":"Wolfgang Wagner","orcid":"https://orcid.org/0000-0001-7704-6857"},"institutions":[{"id":"https://openalex.org/I145847075","display_name":"TU Wien","ror":"https://ror.org/04d836q62","country_code":"AT","type":"education","lineage":["https://openalex.org/I145847075"]}],"countries":["AT"],"is_corresponding":false,"raw_author_name":"Wolfgang Wagner","raw_affiliation_strings":["Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria"],"affiliations":[{"raw_affiliation_string":"Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria","institution_ids":["https://openalex.org/I145847075"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5112001883","display_name":"Richard Kidd","orcid":null},"institutions":[{"id":"https://openalex.org/I145847075","display_name":"TU Wien","ror":"https://ror.org/04d836q62","country_code":"AT","type":"education","lineage":["https://openalex.org/I145847075"]}],"countries":["AT"],"is_corresponding":false,"raw_author_name":"Richard Kidd","raw_affiliation_strings":["Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria"],"affiliations":[{"raw_affiliation_string":"Institute of Photogrammetry and Remote Sensing, University of Technology, Vienna, Vienna, Austria","institution_ids":["https://openalex.org/I145847075"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5090776574","display_name":"Sang-Eun Park","orcid":"https://orcid.org/0000-0003-0887-1348"},"institutions":[{"id":"https://openalex.org/I71395657","display_name":"Niigata University","ror":"https://ror.org/04ww21r56","country_code":"JP","type":"education","lineage":["https://openalex.org/I71395657"]}],"countries":["JP"],"is_corresponding":false,"raw_author_name":"Sang-Eun Park","raw_affiliation_strings":["Graduate School of Science and Technology, Niigata University, Niigata, Japan"],"affiliations":[{"raw_affiliation_string":"Graduate School of Science and Technology, Niigata University, Niigata, Japan","institution_ids":["https://openalex.org/I71395657"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5003634032","display_name":"Kirsten Elger","orcid":"https://orcid.org/0000-0001-5140-8602"},"institutions":[{"id":"https://openalex.org/I127251866","display_name":"Alfred-Wegener-Institut Helmholtz-Zentrum f\u00fcr Polar- und Meeresforschung","ror":"https://ror.org/032e6b942","country_code":"DE","type":"facility","lineage":["https://openalex.org/I127251866","https://openalex.org/I1305996414"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Kirsten Elger","raw_affiliation_strings":["Alfred Wegener Institute\uc2a0of Polar and Marine Research, Potsdam, Germany"],"affiliations":[{"raw_affiliation_string":"Alfred Wegener Institute\uc2a0of Polar and Marine Research, Potsdam, Germany","institution_ids":["https://openalex.org/I127251866"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5011080965","display_name":"Julia Boike","orcid":"https://orcid.org/0000-0002-5875-2112"},"institutions":[{"id":"https://openalex.org/I127251866","display_name":"Alfred-Wegener-Institut Helmholtz-Zentrum f\u00fcr Polar- und Meeresforschung","ror":"https://ror.org/032e6b942","country_code":"DE","type":"facility","lineage":["https://openalex.org/I127251866","https://openalex.org/I1305996414"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Julia Boike","raw_affiliation_strings":["Alfred Wegener Institute\uc2a0of Polar and Marine Research, Potsdam, Germany"],"affiliations":[{"raw_affiliation_string":"Alfred Wegener Institute\uc2a0of Polar and Marine Research, Potsdam, Germany","institution_ids":["https://openalex.org/I127251866"]}]}],"institutions":[],"countries_distinct_count":3,"institutions_distinct_count":8,"corresponding_author_ids":["https://openalex.org/A5052213658"],"corresponding_institution_ids":["https://openalex.org/I145847075","https://openalex.org/I2898391981"],"apc_list":null,"apc_paid":null,"fwci":6.0455,"has_fulltext":false,"cited_by_count":148,"citation_normalized_percentile":{"value":0.96199097,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":96,"max":100},"biblio":{"volume":"50","issue":"7","first_page":"2566","last_page":"2582"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11333","display_name":"Climate change and permafrost","score":0.9998999834060669,"subfield":{"id":"https://openalex.org/subfields/1902","display_name":"Atmospheric Science"},"field":{"id":"https://openalex.org/fields/19","display_name":"Earth and Planetary Sciences"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T11333","display_name":"Climate change and permafrost","score":0.9998999834060669,"subfield":{"id":"https://openalex.org/subfields/1902","display_name":"Atmospheric Science"},"field":{"id":"https://openalex.org/fields/19","display_name":"Earth and Planetary Sciences"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T11312","display_name":"Soil Moisture and Remote Sensing","score":0.9995999932289124,"subfield":{"id":"https://openalex.org/subfields/2305","display_name":"Environmental Engineering"},"field":{"id":"https://openalex.org/fields/23","display_name":"Environmental Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10644","display_name":"Cryospheric studies and observations","score":0.9990000128746033,"subfield":{"id":"https://openalex.org/subfields/1902","display_name":"Atmospheric Science"},"field":{"id":"https://openalex.org/fields/19","display_name":"Earth and Planetary Sciences"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/scatterometer","display_name":"Scatterometer","score":0.8276686668395996},{"id":"https://openalex.org/keywords/environmental-science","display_name":"Environmental science","score":0.697496235370636},{"id":"https://openalex.org/keywords/backscatter","display_name":"Backscatter (email)","score":0.6432005763053894},{"id":"https://openalex.org/keywords/remote-sensing","display_name":"Remote sensing","score":0.6278001070022583},{"id":"https://openalex.org/keywords/permafrost","display_name":"Permafrost","score":0.6150679588317871},{"id":"https://openalex.org/keywords/snowmelt","display_name":"Snowmelt","score":0.5278986096382141},{"id":"https://openalex.org/keywords/northern-hemisphere","display_name":"Northern Hemisphere","score":0.4161013662815094},{"id":"https://openalex.org/keywords/meteorology","display_name":"Meteorology","score":0.3613772988319397},{"id":"https://openalex.org/keywords/atmospheric-sciences","display_name":"Atmospheric sciences","score":0.25532662868499756},{"id":"https://openalex.org/keywords/geology","display_name":"Geology","score":0.22500109672546387},{"id":"https://openalex.org/keywords/snow","display_name":"Snow","score":0.2097455859184265},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.12451666593551636},{"id":"https://openalex.org/keywords/wind-speed","display_name":"Wind speed","score":0.09047955274581909}],"concepts":[{"id":"https://openalex.org/C2776212561","wikidata":"https://www.wikidata.org/wiki/Q905295","display_name":"Scatterometer","level":3,"score":0.8276686668395996},{"id":"https://openalex.org/C39432304","wikidata":"https://www.wikidata.org/wiki/Q188847","display_name":"Environmental science","level":0,"score":0.697496235370636},{"id":"https://openalex.org/C30354325","wikidata":"https://www.wikidata.org/wiki/Q204667","display_name":"Backscatter (email)","level":3,"score":0.6432005763053894},{"id":"https://openalex.org/C62649853","wikidata":"https://www.wikidata.org/wiki/Q199687","display_name":"Remote sensing","level":1,"score":0.6278001070022583},{"id":"https://openalex.org/C15098985","wikidata":"https://www.wikidata.org/wiki/Q179918","display_name":"Permafrost","level":2,"score":0.6150679588317871},{"id":"https://openalex.org/C64649846","wikidata":"https://www.wikidata.org/wiki/Q1754697","display_name":"Snowmelt","level":3,"score":0.5278986096382141},{"id":"https://openalex.org/C2778835443","wikidata":"https://www.wikidata.org/wiki/Q39061","display_name":"Northern Hemisphere","level":2,"score":0.4161013662815094},{"id":"https://openalex.org/C153294291","wikidata":"https://www.wikidata.org/wiki/Q25261","display_name":"Meteorology","level":1,"score":0.3613772988319397},{"id":"https://openalex.org/C91586092","wikidata":"https://www.wikidata.org/wiki/Q757520","display_name":"Atmospheric sciences","level":1,"score":0.25532662868499756},{"id":"https://openalex.org/C127313418","wikidata":"https://www.wikidata.org/wiki/Q1069","display_name":"Geology","level":0,"score":0.22500109672546387},{"id":"https://openalex.org/C197046000","wikidata":"https://www.wikidata.org/wiki/Q7561","display_name":"Snow","level":2,"score":0.2097455859184265},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.12451666593551636},{"id":"https://openalex.org/C161067210","wikidata":"https://www.wikidata.org/wiki/Q1464943","display_name":"Wind speed","level":2,"score":0.09047955274581909},{"id":"https://openalex.org/C555944384","wikidata":"https://www.wikidata.org/wiki/Q249","display_name":"Wireless","level":2,"score":0.0},{"id":"https://openalex.org/C111368507","wikidata":"https://www.wikidata.org/wiki/Q43518","display_name":"Oceanography","level":1,"score":0.0},{"id":"https://openalex.org/C76155785","wikidata":"https://www.wikidata.org/wiki/Q418","display_name":"Telecommunications","level":1,"score":0.0},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.0}],"mesh":[],"locations_count":6,"locations":[{"id":"doi:10.1109/tgrs.2011.2177667","is_oa":false,"landing_page_url":"https://doi.org/10.1109/tgrs.2011.2177667","pdf_url":null,"source":{"id":"https://openalex.org/S111326731","display_name":"IEEE Transactions on Geoscience and Remote Sensing","issn_l":"0196-2892","issn":["0196-2892","1558-0644"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310319808","host_organization_name":"Institute of Electrical and Electronics Engineers","host_organization_lineage":["https://openalex.org/P4310319808"],"host_organization_lineage_names":["Institute of Electrical and Electronics Engineers"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"IEEE Transactions on Geoscience and Remote Sensing","raw_type":"journal-article"},{"id":"pmh:oai:elib.dlr.de:77932","is_oa":false,"landing_page_url":"http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6133332","pdf_url":null,"source":{"id":"https://openalex.org/S4377196266","display_name":"elib (German Aerospace Center)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I2898391981","host_organization_name":"Deutsches Zentrum f\u00fcr Luft- und Raumfahrt e. V. (DLR)","host_organization_lineage":["https://openalex.org/I2898391981"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Zeitschriftenbeitrag"},{"id":"pmh:oai:epic.awi.de:25807","is_oa":false,"landing_page_url":"https://epic.awi.de/id/eprint/25807/","pdf_url":null,"source":{"id":"https://openalex.org/S4306400378","display_name":"Helmholtz-Zentrum f\u00fcr Polar-und Meeresforschung (Alfred-Wegener-Institut)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I2799732068","host_organization_name":"Royal Prince Alfred Hospital","host_organization_lineage":["https://openalex.org/I2799732068"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Article"},{"id":"pmh:oai:gfz-potsdam.de:escidoc:1453930","is_oa":false,"landing_page_url":"http://gfzpublic.gfz-potsdam.de/pubman/item/escidoc:1453930","pdf_url":null,"source":{"id":"https://openalex.org/S4306401313","display_name":"Publication Database GFZ (GFZ German Research Centre for Geosciences)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I4210152878","host_organization_name":"GFZ Helmholtz Centre for Geosciences","host_organization_lineage":["https://openalex.org/I4210152878"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"IEEE Transactions on Geoscience and Remote Sensing","raw_type":"http://purl.org/escidoc/metadata/ves/publication-types/article"},{"id":"pmh:oai:gfzpublic.gfz-potsdam.de:item_1453930","is_oa":false,"landing_page_url":"https://gfzpublic.gfz-potsdam.de/pubman/item/item_1453930","pdf_url":null,"source":{"id":"https://openalex.org/S4306401313","display_name":"Publication Database GFZ (GFZ German Research Centre for Geosciences)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I4210152878","host_organization_name":"GFZ Helmholtz Centre for Geosciences","host_organization_lineage":["https://openalex.org/I4210152878"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"IEEE Transactions on Geoscience and Remote Sensing","raw_type":"info:eu-repo/semantics/article"},{"id":"pmh:oai:gfzpublic.gfz.de:item_1453930","is_oa":false,"landing_page_url":"https://gfzpublic.gfz.de/pubman/item/item_1453930","pdf_url":null,"source":{"id":"https://openalex.org/S4306401313","display_name":"Publication Database GFZ (GFZ German Research Centre for Geosciences)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I4210152878","host_organization_name":"GFZ Helmholtz Centre for Geosciences","host_organization_lineage":["https://openalex.org/I4210152878"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"IEEE Transactions on Geoscience and Remote Sensing","raw_type":"info:eu-repo/semantics/article"}],"best_oa_location":null,"sustainable_development_goals":[{"id":"https://metadata.un.org/sdg/13","score":0.6800000071525574,"display_name":"Climate action"}],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":55,"referenced_works":["https://openalex.org/W178907388","https://openalex.org/W311561747","https://openalex.org/W1509477376","https://openalex.org/W1532691246","https://openalex.org/W1819426174","https://openalex.org/W1966652425","https://openalex.org/W1970641180","https://openalex.org/W1979440117","https://openalex.org/W1990184879","https://openalex.org/W1992697912","https://openalex.org/W1996099728","https://openalex.org/W1996291952","https://openalex.org/W2000703424","https://openalex.org/W2005507895","https://openalex.org/W2014082923","https://openalex.org/W2015129595","https://openalex.org/W2023117794","https://openalex.org/W2028040054","https://openalex.org/W2034956981","https://openalex.org/W2035235584","https://openalex.org/W2043735836","https://openalex.org/W2046371417","https://openalex.org/W2050198538","https://openalex.org/W2055588961","https://openalex.org/W2060476649","https://openalex.org/W2064495430","https://openalex.org/W2065969377","https://openalex.org/W2071641450","https://openalex.org/W2072806535","https://openalex.org/W2075369191","https://openalex.org/W2086599780","https://openalex.org/W2087873369","https://openalex.org/W2105503694","https://openalex.org/W2111890593","https://openalex.org/W2114664960","https://openalex.org/W2118235452","https://openalex.org/W2118430141","https://openalex.org/W2119132330","https://openalex.org/W2121745948","https://openalex.org/W2123744475","https://openalex.org/W2123892463","https://openalex.org/W2125305600","https://openalex.org/W2143491956","https://openalex.org/W2144260774","https://openalex.org/W2148401988","https://openalex.org/W2155897273","https://openalex.org/W2156407014","https://openalex.org/W2161306253","https://openalex.org/W2166252673","https://openalex.org/W2167731682","https://openalex.org/W2170006997","https://openalex.org/W2329933930","https://openalex.org/W4243350966","https://openalex.org/W4249073520","https://openalex.org/W6702422492"],"related_works":["https://openalex.org/W2070850297","https://openalex.org/W2146056128","https://openalex.org/W2113437624","https://openalex.org/W2101982260","https://openalex.org/W3130749594","https://openalex.org/W2566865967","https://openalex.org/W2045934768","https://openalex.org/W790100635","https://openalex.org/W1996875821","https://openalex.org/W4237414713"],"abstract_inverted_index":{"Information":[0],"on":[1,28,129],"soil":[2,41,50,113,145,172],"surface":[3,29,136],"state":[4,33,137],"is":[5,52,62],"valuable":[6],"for":[7,86],"many":[8],"applications":[9],"such":[10],"as":[11,119,149,151],"climate":[12],"studies":[13],"and":[14,82,124,184],"monitoring":[15],"of":[16,36,45,48,68,88,121,191],"permafrost":[17],"regions.":[18],"C-band":[19],"scatterometer":[20,56,104],"data":[21,101,147,174],"indicate":[22],"good":[23],"potential":[24],"to":[25,64,70,194],"deliver":[26],"information":[27],"freeze/thaw.":[30],"Variation":[31],"in":[32,39,55,73,178,182],"or":[34,126],"amount":[35],"water":[37,128],"contained":[38],"the":[40,49,75,130,152,161,188],"causes":[42],"significant":[43],"alteration":[44],"dielectric":[46],"properties":[47],"which":[51],"markedly":[53],"observable":[54],"backscattered":[57],"signal.":[58],"A":[59],"threshold-analysis":[60],"method":[61],"developed":[63],"derive":[65],"a":[66],"set":[67],"parameters":[69,93],"be":[71],"used":[72],"evaluating":[74],"normalized":[76],"backscatter":[77,100],"measurements":[78,116,155],"through":[79],"decision":[80],"trees":[81],"anomaly":[83],"detection":[84],"modules":[85],"determination":[87],"freeze/thaw":[89],"conditions.":[90],"The":[91,132,164],"model":[92],"are":[94,117,168],"extracted":[95],"from":[96,102,156],"two":[97,143],"years":[98],"(2007-2008)":[99],"ASCAT":[103],"onboard":[105],"Metop":[106],"satellite":[107],"collocated":[108],"with":[109,142,171],"ECMWF":[110],"ReAnalysis":[111],"(ERA-Interim)":[112],"temperature.":[114],"Backscatter":[115],"flagged":[118],"indicator":[120],"frozen/unfrozen":[122],"surface,":[123],"snowmelt":[125],"existing":[127],"surface.":[131],"output":[133],"product,":[134],"so-called":[135],"flag":[138],"(SSF),":[139],"compares":[140],"well":[141,150],"modeled":[144],"temperature":[146,154,173],"sets":[148],"air":[153],"synoptic":[157],"meteorological":[158],"stations":[159],"across":[160],"northern":[162],"hemisphere.":[163],"SSF":[165],"time":[166],"series":[167],"also":[169],"validated":[170],"available":[175],"at":[176],"four":[177],"situ":[179],"observation":[180],"sites":[181],"Siberian":[183],"Alaska":[185],"regions":[186],"showing":[187],"overall":[189],"accuracy":[190],"about":[192],"80%":[193],"90%.":[195]},"counts_by_year":[{"year":2026,"cited_by_count":1},{"year":2025,"cited_by_count":7},{"year":2024,"cited_by_count":12},{"year":2023,"cited_by_count":16},{"year":2022,"cited_by_count":19},{"year":2021,"cited_by_count":8},{"year":2020,"cited_by_count":5},{"year":2019,"cited_by_count":13},{"year":2018,"cited_by_count":14},{"year":2017,"cited_by_count":16},{"year":2016,"cited_by_count":10},{"year":2015,"cited_by_count":7},{"year":2014,"cited_by_count":8},{"year":2013,"cited_by_count":6},{"year":2012,"cited_by_count":5}],"updated_date":"2026-04-04T16:13:02.066488","created_date":"2025-10-10T00:00:00"}