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Interdisciplinary approaches are needed to reconstruct the behaviour of glaciers beyond the beginning of systematic measurements. For example, historical documents have been used to reconstruct former glacier extents successfully at different sites, including in the well-documented Mont Blanc area that became popular since the mid-18th century among artists, scientists, and travellers. Jean-Antoine Linck from Geneva is probably the artist to whom we owe the greatest number of unique glacier views. Linck’s special preference were the ice regions, which he discovered and drew with alpinistic daring and naturalistic correctness, preferably by gouache, although many pencil sketches are preserved. Linck subtly used the etching technique to create easily reproducible plates in large format, which are then hand-coloured with gouache and watercolour. This technique allowed him to create numerous reproductions of the same view, while still giving them a unique and original aspect, views that are remarkable for their serenity and silence, while offering luminous atmospheres. These illustrations introduced the realistic representation of the high mountains into the iconography of Genevese painting and thus led to a new kind of landscape painting with a permanent character. From a perspective of glacier history and although many of his artworks are not exactly dated by the author, the work of Jean-Antoine Linck is indispensable since it represents the whole development, specifically of the Mer de Glace and the Glacier des Bossons, but also other glaciers during the period from the end of the 18th century until the 19th century glacier maximum around 1820. Linck’s work has the same importance for the Mont Blanc area as that of Caspar Wolf and Samuel Birmann for the central Swiss Alps or Thomas Ender for the Austrian Alps in terms of glacier iconography. Therefore, Linck was both an artist and a glacier historian. // Des approches interdisciplinaires sont nécessaires pour reconst

Les glaciers sont considérés comme des indicateurs climatiques clés, car ils réagissent de manière sensible aux changements climatiques passés. Pour reconstruire l’évolution des glaciers pendant le Petit âge glaciaire, la méthode historique est particulièrement adaptée. Cet article montre des exemples de la région du Mont-Blanc et des Alpes centrales suisses, deux régions caractérisées par l’apparition de sources iconographiques de haute qualité au 18e siècle. Dans les deux régions, deux avancées glaciaires très prononcées s’étant déroulées vers 1720 et dans les années 1770 sont documentées par les sources historiques. Parallèlement, on constate un changement de perception de l’objet magique-mystérieux à l’objet d’étude scientifique : les glaciers étaient avant tout perçus comme une menace au début du 18e siècle, la perception a changé lorsque les glaciers sont devenus un élément fascinant pour les artistes et touristes et un objet d’étude pour les scientifiques. Finalement, les glaciers du 18e siècle contrastent fortement avec la situation actuelle de fonte globale des glaciers.

The Finsteraarhorn, the highest peak in the Bernese Alps, and the Jungfrau, renowned for its cog railway that attracts a high number of tourists each year, are together in the heart of a high mountain glacier landscape. The Unteraar Glacier with an east-oriented and extensively debris-covered tongue has, since the eighteen/nineteenth century, been the cradle of glacier research (e.g. L. Agassiz). In turn, Lower Grindelwald Glacier became historically the best-documented Swiss valley glacier, thanks to its accessible, low-altitude ice-front position. A wealth of high-quality depictions by top artists (e.g. C. Wolf and S. Birmann) have allowed the reconstruction of the Little Ice Age (LIA) glacier fluctuations in a uniquely precise way. The Upper Lauterbrunnen Valley, dominated on both sides by huge steep rock walls with a great number of waterfalls, hosts smaller glaciers and a collection of moraines in the valley bottom. Since the end of the LIA, all the glaciers have been melting back, with a dramatic increase in recent years. The Lower Grindelwald Glacier, for instance, shows a reduction of the ice volume by 50% since the end of the LIA. By the end of the twenty-firstc entury, the Finsteraarhorn–Jungfrau landscape will no longer exist in the form it has been renowned for over the last centuries.

Comprehensive assessments of global glacier mass changes based on a variety of observations and prevailing methodologies have been published at multi-annual intervals. For the years in between, the glaciological method provides annual observations of specific mass changes but is suspected to not be representative at the regional to global scales due to uneven glacier distribution with respect to the full sample. Here, we present a simple approach to estimate and correct for this bias in the glaciological sample and, hence, to provide an ad hoc estimate of global glacier mass changes and corresponding sea-level equivalents for the latest years, i.e. about −300±250 Gt in 2016/17 and −500±200 Gt in 2017/18.

Comprehensive assessments of global glaciermass changes based on a variety of observations and prevailing methodologies have been published at multi-annual intervals. For the years in between, the glaciological method provides annual observations of specific mass changes but is suspected to not be representative at the regional to global scales due to uneven glacier distribution with respect to the full sample. Here, we present a simple approach to estimate and correct for this bias in the glaciological sample and, hence,to provide an ad hoc estimate of global glacier mass changes and corresponding sea-level equivalents for the latest years, i.e. about −300±250 Gt in 2016/17 and −500±200 Gt in 2017/18.