{"id":77,"date":"2022-01-10T20:58:07","date_gmt":"2022-01-10T20:58:07","guid":{"rendered":"http:\/\/ny.cryoclim.net\/?page_id=77"},"modified":"2023-03-27T14:00:23","modified_gmt":"2023-03-27T14:00:23","slug":"glaciers-mainland-norway","status":"publish","type":"page","link":"http:\/\/www.cryoclim.net\/?page_id=77","title":{"rendered":"Glaciers Mainland Norway"},"content":{"rendered":"\t\t
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Glaciers Mainland Norway (NVE)<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Product summary<\/b><\/i><\/span><\/p>

Glacier products from mainland Norway in the CryoClim service consist of Glacier Area Outline (GAO), Glacier Lake Outlines (GLO), Glacier Periodic Photo series (GPP) and Climate Indicator products. The GAO and GLO products are based on Sentinel-2 MSI and Landsat TM\/ETM+\/OLI images using image analysis and geographic information system (GIS) techniques. The GPP products are time series of glacier photographs (terrestrial and airborne imagery without geo-referencing) and are used to illustrate changes for selected glaciers. The climate indicator products display NVE\u2019s records of surface mass balance and length change for glaciers in mainland Norway. The data are retrieved directly from NVE\u2019s database. For some of the glaciers area maps are also shown.<\/span><\/p>

Background<\/b><\/i><\/span><\/p>

Glaciers are particularly sensitive to changes in climate. When a glacier advances or retreats its surface area also changes and new glacier lakes form, grow, vanish, or are detached from the glacier. Glacier outline datasets are important input to many types of analysis and modelling, and valuable in glacier change studies. While the mass balance of a glacier reflects annual weather directly, records of length change (also termed front-position change) can be used for climate change detection on a decadal-to-century time scale. Imagery of glaciers are useful to display glacier and climate changes for a wider audience.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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The glacier lake product (GLO) for 2019 was derived from the glacier area outline (GAO) mapping using a Sentinel-2 image of 27 August 2019. Line edits (in red) were used to detach glacier lakes (blue) from the glacier outlines (yellow). The section shows part of south-eastern Sp\u00f8rteggbreen to the right and a former part of Sp\u00f8rteggbreen to the left. The outlines for earlier GLO products reveal growth of glacier lakes. The lakes appear black in contrast to glaciers in blue in this false colour composite (bands 11-8-4 shown as RGB). Figure from Andreassen et al. (2021) (Copernicus Sentinel data)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Retrieval algorithm<\/b><\/i><\/span><\/p>\n

Glacier area outline (GAO) is mapped using manual digitation from topographic maps and segmentation of ratio images for satellite imagery (Landsat TM\/ETM+\/OLI, Seninel-2). Manual edits are needed to correct for seasonal snow, debris, lakes and parts in shadow.<\/p>\n

Glacier lake outline (GLO) is mapped using a combination of methods: normalized difference water index (NDWI), manual digitisation, band thresholding and by map overlay with lakes from topographic digital maps (Andreassen et al. 2021).<\/p>\n

The algorithms required to effectively extract glacial variables from satellite images depend upon illumination conditions, landscape types and scene conditions. Manual adaption is needed to check the suitability of algorithms for each region and scene.<\/p>\n

Validation<\/b><\/i><\/span><\/p>\n

The applicability of standard glacier mapping methods is tested using orthophotos from norgeibilder.no and other sources. Results so far confirm that the glacier outlines and lake outlines can be mapped accurately, but that the automatic mapping often needs manual corrections. Automatically derived outlines are therefore checked against the satellite imagery, orthophotos and topographic maps, and manual corrections applied when needed.<\/span><\/p>\n

Reference:<\/b><\/i><\/span><\/p>\n

Andreassen, L. M. (ed.), G. Moholdt, A. K\u00e4\u00e4b, A. Messerli, T. Nagy and S.H. Winsvold, 2021. Monitoring glaciers in mainland Norway and Svalbard using Sentinel. NVE Rapport 3-2021, 94 s. https:\/\/publikasjoner.nve.no\/rapport\/2021\/rapport2021_03.pdf<\/a><\/span><\/p>\n

Handle access<\/em> <\/strong><\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
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Institution\/sub-service<\/b><\/span><\/span><\/span><\/p>\n<\/td>\n

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Variable\/dataset<\/b><\/span><\/span><\/span><\/p>\n<\/td>\n

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Handle<\/b><\/span><\/span><\/span><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Lake Outline (GAO) 2018<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828426<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Lake Outline (GAO) 2014<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828423<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Lake Outline 1988-1997<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2830997<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Lake Outline 1999-2006<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2831001<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Lake Outline 2018-2019<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2836905<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outline 2018-2019<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2836926<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outline 1999-2006<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2831059<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outline 1988-1997<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2831057<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outline 1947-1985<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2831053<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outline 1895-1907<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2831051<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outlines Hardangerj\u00f8kulen<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828313<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outlines Vestre Svartisen LIA<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828404<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outlines Nordland 1900<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828334<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n

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NVE mainland Norway<\/span><\/span><\/span><\/p>\n<\/td>\n

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Glacier Area Outlines Langfjordj\u00f8kelen<\/span><\/span><\/span><\/p>\n<\/td>\n

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https:\/\/hdl.handle.net\/11250\/2828394<\/span><\/span><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"

Glaciers Mainland Norway (NVE) Product summary Glacier products from mainland Norway in the CryoClim service consist of Glacier Area Outline (GAO), Glacier Lake Outlines (GLO), Glacier Periodic Photo series (GPP) and Climate Indicator products. The GAO and GLO products are based on Sentinel-2 MSI and Landsat TM\/ETM+\/OLI images using image analysis and geographic information system […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-77","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/pages\/77","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=77"}],"version-history":[{"count":31,"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/pages\/77\/revisions"}],"predecessor-version":[{"id":540,"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=\/wp\/v2\/pages\/77\/revisions\/540"}],"wp:attachment":[{"href":"http:\/\/www.cryoclim.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=77"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}