# Glacier thickness A thematic map of the Atlas of Switzerland, the national atlas published by ETH Zurich. The map is drawn in the browser; this file describes it and lists its variants and links, but not the data values shown on the map. - Map: https://atlasderschweiz.ch/en/theme/glacier-thickness/ - Map id: 998 - Categories: Nature and Environment › Ice and Snow › Glaciers - Keywords: Environment, Geology, Glaciation, Glacier, Mountains - Published: 2022-04-13 - Last revised: 2022-04-13 - Content language: English - Other languages: [Deutsch](https://atlasderschweiz.ch/de/thema/gletschermaechtigkeit.md), [Français](https://atlasderschweiz.ch/fr/theme/epaisseur-des-glaciers.md), [Italiano](https://atlasderschweiz.ch/it/tema/spessore-dei-ghiacciai.md) ## Description The alpine late-glacial period ended approximately 11,600 years ago with the recession of Ice Age glaciers to the Holocene or recent size (e.g. as around 1850). Since then, alpine glaciers have been fluctuating within a narrowly limited range only at a high temperature level and an astonishingly low amplitude (± 1 °C). There is conclusive evidence, based on historical glaciology studies, of eight major advance cycles and as many retreat phases covering the last 11,600 years (Holocene, postglacial). During these Holocene cold phases, the glacier delineation and tongue positions always attained comparable extents and ranges. The advance phase around 1850, with its striking moraine zones (terminal and embankment moraines) constitutes the culmination and conclusion of this period of generally major glacier extents lasting over several centuries. This phase is commonly referred to as the «Little Ice Age» (period of 1250 to 1850, approx.). The glacier forefields, subsequently freed from ice, can be recognized by the areas of fresh morainic debris and the as-yet sparse vegetation. In the cool phases of the Holocene, these pro-glacial areas were repeatedly covered with ice, and then became ice-free in the retreat phases. For this reason, the maximum extent of 1850 serves as a key variable for determining and calibrating the climatic fluctuations of the Holocene. This phase is well documented (e.g., with maps and pictures) based on historical records from the period around the middle of the 19th century. The glaciers of the Alps were depicted at the point of their last maximum extent in the first overall topographic record of Switzerland (for the making of the Dufour map, at a scale of 1:100,000). Glaciomorphological findings enable a detailed reconstruction of the glacier extent around 1850. In such manner, extensive data were collected, and in comparison with the current situation (Swiss Glacier Inventories of 1973 and 1998) it was possible to illustrate and analyze the «retreat of the century». The glaciated surface of the Swiss Alps diminished from 1800 km² in 1850 to 1300 km² in 1973 and to 860 km² in 2023. With reference to the surface area of Switzerland, the glaciated portion was reduced from 4.4% to around 2%. Large glaciers, such as the Grosser Aletsch, Gorner, and Morteratsch had the greatest amount of recession, with respect to surface area, volume and length values, seen in absolute terms. However, their losses were less, at 10 to 25 %, than the medium-sized glaciers, at 30–50%, or the small glaciers, at 50 to 80%. Several hundred small firn patches melted away completely during the last 150 years. The retreat tendency is continuing at present and seems even to be accelerating, in line with climatic developments (glacier retreat scenario for 2050). ## Sources - Universität Freiburg (2014): [Gletscherschwund: Eisfläche nur noch so gross wie der Kanton Schwyz](http://www.unifr.ch/news/de/13448/). Freiburg: Universität Freiburg - Huss et al. (2025): [GLAMOS, 2026. Swiss Glacier Bulletin 2025](https://doi.glamos.ch/pubs/glbulletin/glbulletin_2025.pdf) - Huss et al. (2025): [Gletscher der Schweiz. Zustand, Prognosen und Bedeutung](https://portal-cdn.scnat.ch/asset/5fcd0f74-de25-5157-8072-01967846e0ec/Factsheet_Gletscher_D_Online.pdf?b=ad746522-7c37-5c23-bdbe-2d1611c63f99&v=4b3d34cf-55a4-5ef0-8321-287fdfff92ef_0&s=lt-oMrznzDPl5Zkq-OzCoLt9bDKqi87-zwNqQnVh8eb2oHwv-Wr7IVo4lDXllVCMi0WNY1DlprnmPE3GNodXWLPpmyzacoM5efjZj2EAJ_oXRxfcgDC8y1y08-RrqgexT_TPhka_lifE8iFckCUSLKu-r2y7MX8jvkDikxCA1KI). Swiss Academies Factsheets 20 (2) ## Data sources - Grab (2020): [Swiss Glacier Thickness – Release 2020](https://www.research-collection.ethz.ch/handle/20.500.11850/434697). ETH Zürich ## Data owners - [Laboratory of Hydraulics, Hydrology and Glaciology, ETH Zurich (VAW)](http://www.vaw.ethz.ch/) ## Authors - [Department of Geography, University of Zurich (GIUZ)](https://www.geo.uzh.ch/de.html) ## Citation The terms of use ask to name the Atlas of Switzerland and the data owners, and to keep the source references in exports, screenshots and embeds. Cite the map as: > Atlas of Switzerland (2022): Glacier thickness. ETH Zürich. Map data © VAW. https://atlasderschweiz.ch/en/theme/glacier-thickness/ ## Links The map opens at its full extent; a link cannot set the map position. - Map: https://atlasderschweiz.ch/en/theme/glacier-thickness/ - Short link, stays valid when the title changes: https://atlasderschweiz.ch/en/t/998/ - Side by side with another map: https://atlasderschweiz.ch/en/comparison/?lt=998&rt={id of the other map}&ru={u of the other map, or leave out} Embed in another website (allowed by the terms of use, as long as the source references stay visible): ```html ``` In the embed URL, `dm` sets what is shown: `e` the map with its title bar (default), `p` also the values of an object clicked on the map, `m` only the map with a button that opens it in the atlas. `ig=1` (default) lets the map react to scrolling and dragging only after a click into it, `ig=0` right away. The size can be changed in `style`. ## Related maps - [Glacier extension during the Last Glacial Maximum (Würm period)](https://atlasderschweiz.ch/en/theme/glacier-extension-during-the-last-glacial-maximum-wuerm-period.md) (id 198, former edition, desktop atlas only) - [Glacier extension in Europe during the Last Glacial Maximum (Würm period)](https://atlasderschweiz.ch/en/theme/glacier-extension-in-europe-during-the-last-glacial-maximum-wuerm-period.md) (id 416, former edition, desktop atlas only) For the use and citation of maps and data, see the [terms of use](https://atlasderschweiz.ch/en/terms-of-use/).