{"id":51841,"date":"2025-12-16T09:00:00","date_gmt":"2025-12-16T08:00:00","guid":{"rendered":"https:\/\/marineforum.online\/?p=51841"},"modified":"2025-12-08T13:27:08","modified_gmt":"2025-12-08T12:27:08","slug":"new-algorithm-sea-ice-thickness-arctic","status":"publish","type":"post","link":"https:\/\/marineforum.online\/en\/neuer-algorithmus-meereisdicke-arktis\/","title":{"rendered":"This is how thick the sea ice is in the Arctic Ocean"},"content":{"rendered":"<h4>New algorithm provides unprecedented information for climate research<\/h4>\n<div class=\"block introduction next--is--same--backgroundColor previous--is--same--backgroundColor is--first--of--block-type is--last--of--block-type next--is--separator\">\n<div class=\"block-container\">\n<ul>\n<li>An algorithm developed at DLR provides the first high-resolution maps that allow conclusions to be drawn about the current sea ice thickness.<\/li>\n<li>This is made possible by combining data from the European Sentinel-1 radar satellites with measurements from the ATLAS laser altimeter on board NASA's ICESat-2 satellite.<\/li>\n<li>The resolution of the generated sea ice maps is 100 metres and exceeds that of the previous maps from compiled measurements by a factor of 250.<\/li>\n<li>The knowledge gained forms a new basis for environmental and climate science.<\/li>\n<li>Focal points: Space travel, earth observation, climate research, transport, maritime research<\/li>\n<\/ul>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor next--is--same--block-type is--first--of--block-type next--is--slate\">\n<p>The Arctic is one of the least developed areas on Earth - at the same time, the changes caused by global warming are being felt more clearly here than in any other region. The sea ice cover has been decreasing for years and the existing ice is thinning. The German Aerospace Centre (DLR) has developed a new algorithm that combines radar satellite images from the European Sentinel-1 mission and elevation profile measurements from NASA's ICESat-2 satellite, enabling a high-resolution calculation of ice thickness for the first time. Sea ice plays an important role in the Earth's climate. The white, snow-covered surfaces reflect sunlight into space. Thinner ice appears darker because it is more transparent and allows the seawater to shine through. As a result, thinner ice also reflects less sunlight back into space. It is getting warmer: not only in the Arctic, but everywhere on Earth.<\/p>\n<figure id=\"attachment_51845\" aria-describedby=\"caption-attachment-51845\" style=\"width: 217px\" class=\"wp-caption alignleft\"><a href=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-karl-Kortum.jpg\"><img fetchpriority=\"high\" decoding=\"async\" class=\"wp-image-51845 size-medium\" src=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-karl-Kortum-217x300.jpg\" alt=\"\" width=\"217\" height=\"300\" srcset=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-karl-Kortum-217x300.jpg 217w, \/wp-content\/uploads\/2025\/12\/2025-DLR-karl-Kortum-9x12.jpg 9w, \/wp-content\/uploads\/2025\/12\/2025-DLR-karl-Kortum.jpg 400w\" sizes=\"(max-width: 217px) 100vw, 217px\" \/><\/a><figcaption id=\"caption-attachment-51845\" class=\"wp-caption-text\">Dr Karl Kortum, DLR Institute of Remote Sensing Technology in Bremen Photo: DLR<\/figcaption><\/figure>\n<p>\"Certain sea ice properties such as ice concentration or the age of the ice are traditionally read from satellite data and have formed the basis for research into the Earth's climate system for decades. Until now, the ice thickness could not be measured comprehensively from satellite images. Our new algorithm now provides information on ice thickness for the first time, which could significantly improve the navigation of ships in polar waters, for example.\"<\/p>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor next--is--same--block-type is--first--of--block-type next--is--slate\">\n<p id=\"79d4e050-3e22-4cfa-8cb3-44519ab559b1\"><strong>How satellites measure sea ice<\/strong><\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p>Laser altimeters installed on satellites measure a height profile along a line under the satellite and thus the so-called freeboard of the ice, i.e. the height of the ice above sea level. Altimeters are an important instrument for climate research from space - however, they are only used for linear measurements. In order to obtain comprehensive maps, all measurements for a month must be compiled, whereby the map resolution is then only 25 kilometres.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type is--last--of--block-type next--is--slateTable\">\n<p>Radar satellites provide two-dimensional images of the Earth's surface, in which land masses, bodies of water, ice surfaces and, within the ice, various structures such as ice ridges or meltwater become visible. The size and resolution of the images can be adjusted. As a rule, a Sentinel-1 image of the Arctic covers an area of 400 by 400 kilometres. Germany could be almost completely covered with two images from the radar satellite. The image resolution is 40 metres.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor next--is--same--block-type is--first--of--block-type next--is--slate\">\n<p id=\"523031fe-5b60-4917-a8a5-790efcad2a0e\"><strong>From the ice surface to the ice thickness<\/strong><\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<figure id=\"attachment_51846\" aria-describedby=\"caption-attachment-51846\" style=\"width: 373px\" class=\"wp-caption alignright\"><a href=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis.jpg\"><img decoding=\"async\" class=\"wp-image-51846\" src=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis-300x169.jpg\" alt=\"Sea ice in a satellite-based radar image Photo: DLR\" width=\"373\" height=\"210\" srcset=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis-300x169.jpg 300w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis-768x432.jpg 768w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis-18x10.jpg 18w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Meereis.jpg 1000w\" sizes=\"(max-width: 373px) 100vw, 373px\" \/><\/a><figcaption id=\"caption-attachment-51846\" class=\"wp-caption-text\">Sea ice in a satellite-based radar image Photo: DLR<\/figcaption><\/figure>\n<p>Images from radar satellites show \"echoes\" of the earth's surface. The satellites transmit a radar signal from their orbits at an altitude of several hundred kilometres, which the earth's surface reflects differently depending on the type of subsurface. The satellite then measures the reflected echoes, analyses them and compiles them into an image that shows the surface of the earth and ice. However, the radar images from space only show the surface composition of the ice, not the ice thickness.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p>However, the new algorithm developed by the DLR Remote Sensing Technology Institute in Bremen does just that: by comparing the radar signal with altimeter data, information is assigned to the radar signal that is related to the ice thickness. Overall, the algorithm generates ice maps of the height or thickness of the ice above sea level - the freeboard. When snow and density information is added, the total ice thickness can be calculated.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p>In a recent study, the researchers were able to demonstrate the functionality of the new algorithm. The resolution of the generated sea ice maps is 100 metres, surpassing the previous maps from monthly altimeter measurements by a factor of 250. This means that fine differences within the ice are now visible across the entire area for the first time.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p id=\"d10e4279-6380-4675-97b1-7b9790598876\"><strong>Tracking movements in the ice<\/strong><\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<figure id=\"attachment_51847\" aria-describedby=\"caption-attachment-51847\" style=\"width: 364px\" class=\"wp-caption alignleft\"><a href=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit.jpeg\"><img decoding=\"async\" class=\"wp-image-51847\" src=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-300x169.jpeg\" alt=\"\" width=\"364\" height=\"205\" srcset=\"\/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-300x169.jpeg 300w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-1024x576.jpeg 1024w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-768x432.jpeg 768w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-1536x864.jpeg 1536w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit-18x10.jpeg 18w, \/wp-content\/uploads\/2025\/12\/2025-DLR-Satellit.jpeg 1920w\" sizes=\"(max-width: 364px) 100vw, 364px\" \/><\/a><figcaption id=\"caption-attachment-51847\" class=\"wp-caption-text\">The Sentinel-1 mission Photo: DLR<\/figcaption><\/figure>\n<p>The European radar satellites of the Sentinel-1 mission are travelling in an orbit close to the poles, which allows them to image regions at high latitudes more frequently - some Arctic waters several times a day. This is important because wind and ocean currents are constantly changing the ice. Within a few hours, loose ice floes can be pushed together and close open water areas. If the pressure persists, ice floes pile up on top of and under each other, or they can be raised vertically. The ice ridges formed in this way can become metres thick. However, it is also possible for a closed ice sheet to break up and be removed by opposing forces.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p>The new algorithm, which is based on Sentinel-1 images, not only allows conclusions to be drawn about the ice thickness at a much higher resolution, but also at a faster rate. The ice maps generated show the constantly changing topography of the oldest floes in the Arctic in great detail. They not only create a new basis for environmental and climate science, but could also revolutionise shipping in the Arctic. Shipping routes that pass through thinner ice are more efficient and safer. The study for the new algorithm was carried out in collaboration with the <strong>Danish Meteorological Institute and the University of Bremen<\/strong> carried out. The DLR is currently planning a research project together with Drift+Noise Polar Services to investigate the suitability of the new ice charts for guiding ships. This is because the thickness of the ice, even if it is only the part above sea level, is important information for ship masters that has never been available before.<\/p>\n<\/div>\n<div class=\"slate next--is--same--backgroundColor previous--is--same--backgroundColor previous--is--same--block-type next--is--same--block-type next--is--slate\">\n<p><strong>This article was kindly provided by the German Aerospace Centre (DLR).<\/strong><\/p>\n<p class=\"headline\">Contact, e-mail: <a class=\"moz-txt-link-abbreviated\" href=\"mailto:jana.hoidis@dlr.de\">jana.hoidis@dlr.de<\/a><\/p>\n<div class=\"ui stackable two column grid\">\n<div class=\"row\">\n<div class=\"column\">\n<div class=\"contact-detail\">\n<p class=\"name\">Jana Hoidis, Communications Bremen, Bremerhaven, Hamburg, Oldenburg, Kiel, Geesthacht<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Neuer Algorithmus liefert bisher nie dagewesene Informationen f\u00fcr die Klimaforschung Ein am DLR entwickelter Algorithmus liefert erstmals hochaufgel\u00f6ste Karten, die R\u00fcckschl\u00fcsse auf die aktuelle Meereisdicke erlauben. Erm\u00f6glicht wird dies durch die Kombination von Daten der europ\u00e4ischen Radarsatelliten Sentinel-1 mit Messungen des Laseraltimeters ATLAS an Bord des NASA-Satelliten ICESat-2. Die Aufl\u00f6sung der erzeugten Meereiskarten liegt bei [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":51881,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_oasis_is_in_workflow":0,"_oasis_original":0,"_oasis_task_priority":"2normal","footnotes":""},"categories":[52,486,42,50],"tags":[11412,641,6357,11421,8516,11418,11410,11413,11419,11422,11409,10011,11416,8963,11407,11411,11420,8192,11417,8561,11415,11408,11414],"class_list":["post-51841","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technologie-news","category-headlines","category-news","category-sicherheitspolitik-news","tag-algorithmus","tag-arktis","tag-arktischer-ozean","tag-datenanalyse","tag-dlr","tag-eiskarten","tag-erdbeobachtung","tag-fernerkundung","tag-freibord","tag-hochaufgeloeste-karten","tag-icesat-2","tag-klimaforschung","tag-laseraltimeter","tag-maritime-forschung","tag-meereisdicke","tag-meereisforschung","tag-navigation-arktis","tag-polarforschung","tag-radarsatellit","tag-raumfahrt","tag-satellitendaten","tag-sentinel-1","tag-umweltforschung"],"acf":[],"_links":{"self":[{"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/posts\/51841","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/comments?post=51841"}],"version-history":[{"count":9,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/posts\/51841\/revisions"}],"predecessor-version":[{"id":51869,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/posts\/51841\/revisions\/51869"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/media\/51881"}],"wp:attachment":[{"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/media?parent=51841"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/categories?post=51841"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/marineforum.online\/en\/wp-json\/wp\/v2\/tags?post=51841"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}