{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T05:03:45Z","timestamp":1769576625255,"version":"3.49.0"},"reference-count":49,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2017,11,11]],"date-time":"2017-11-11T00:00:00Z","timestamp":1510358400000},"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 lowest elevation of spring snow (\u201csnowline\u201d) is an important factor influencing recruitment and survival of wildlife in alpine areas. In this study, we assessed the spatial and temporal variability of alpine spring snowline across major Dall sheep mountain areas in Alaska and northwestern Canada. We used a daily MODIS snow fraction product to estimate the last day of 2000\u20132016 spring snow for each 500-m pixel within 28 mountain areas. We then developed annual (2000\u20132016) regression models predicting the elevation of alpine snowline during mid-May for each mountain area. MODIS-based regression estimates were compared with estimates derived using a Normalized Difference Snow Index from Landsat-8 Operational Land Imager (OLI) surface reflectance data. We also used 2000\u20132009 decadal climate grids to estimate total winter precipitation and mean May temperature for each of the 28 mountain areas. Based on our MODIS regression models, the 2000\u20132016 mean May 15 snowline elevation ranged from 339 m in the cold arctic class to 1145 m in the interior mountain class. Spring snowline estimates from MODIS and Landsat OLI were similar, with a mean absolute error of 106 m. Spring snowline elevation was significantly related to mean May temperature and total winter precipitation. The late spring of 2013 may have impacted some sheep populations, especially in the cold arctic mountain areas which were snow-covered in mid-May, while some interior mountain areas had mid-May snowlines exceeding 1000 m elevation. We found this regional (&gt;500,000 km2) remote sensing application useful for determining the inter-annual and regional variability of spring alpine snowline among 28 mountain areas.<\/jats:p>","DOI":"10.3390\/rs9111157","type":"journal-article","created":{"date-parts":[[2017,11,13]],"date-time":"2017-11-13T11:12:36Z","timestamp":1510571556000},"page":"1157","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Remote Sensing of 2000\u20132016 Alpine Spring Snowline Elevation in Dall Sheep Mountain Ranges of Alaska and Western Canada"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6887-3957","authenticated-orcid":false,"given":"David","family":"Verbyla","sequence":"first","affiliation":[{"name":"School of Natural Resources and Extension, University of Alaska Fairbanks, Fairbanks, AK 99775, USA"}]},{"given":"Troy","family":"Hegel","sequence":"additional","affiliation":[{"name":"Yukon Department of Environment, Whitehorse, YT Y1A 4Y9, Canada"}]},{"given":"Anne","family":"Nolin","sequence":"additional","affiliation":[{"name":"College of Earth, Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA"}]},{"given":"Madelon","family":"Van de Kerk","sequence":"additional","affiliation":[{"name":"School of Environmental and Forestry Sciences, University of Washington, Seattle, WA 98195, USA"}]},{"given":"Thomas","family":"Kurkowski","sequence":"additional","affiliation":[{"name":"Scenarios Network for Alaska and Arctic Planning, University of Alaska Fairbanks, Fairbanks, AK 99775, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9045-3107","authenticated-orcid":false,"given":"Laura","family":"Prugh","sequence":"additional","affiliation":[{"name":"School of Environmental and Forestry Sciences, University of Washington, Seattle, WA 98195, USA"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1007\/s13280-011-0212-y","article-title":"The changing face of Arctic snow cover: A synthesis of observed and projected changes","volume":"40","author":"Callaghan","year":"2011","journal-title":"AMBIO"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"482","DOI":"10.1038\/nature09210","article-title":"Coupled dynamics of body mass and population growth in response to environmental change","volume":"466","author":"Ozgul","year":"2010","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1453","DOI":"10.1111\/j.1600-0706.2010.18358.x","article-title":"Interacting effect of wolves and climate on recruitment in a northern mountain caribou population","volume":"119","author":"Hegel","year":"2010","journal-title":"Oikos"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"20","DOI":"10.2307\/3803057","article-title":"Marrow fat deposition and skeletal growth in caribou calves","volume":"67","author":"Adams","year":"2003","journal-title":"J. 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