Little ice age glacier history of the central and western alps from pictorial documents

The Lower Grindelwald Glacier (Bernese Oberland, Switzerland) consists of two parts, the Ischmeer in the east (disconnected) and the Bernese Fiescher Glacier in the west. During the Little Ice Age (LIA), the glacier terminated either in the area of the “Schopffelsen” (landmark rock terraces) or advanced at least six times (ten times if we include early findings) even further down into the valley bottom forming the “Schweif” (tail). Maximal ice extensions were reached in 1602 and 1855/56 AD. The years after the end of the LIA have been dominated by a dramatic melting of ice, especially after 2000. The Mer de Glace (Mont Blanc area, France) is a compound valley glacier formed by the tributaries Glacier du Tacul, Glacier de Léschaux, and Glacier de Talèfre (disconnected). During the LIA, the Mer de Glace nearly continuously reached the plain in the Chamonix Valley (maximal extensions in 1644 and 1821 AD). The retreat, beginning in the mid-1850s, was followed by a relatively stable position of the front (1880s until 1930s). Afterwards the retreat has continued until today, especially impressive after 1995. The perception of glaciers in the early times was dominated by fear. In the age of Enlightenment and later in the 19th century, it changed to fascination. In the 20th century, glaciers became a top attraction of the Alps, but today they are disappearing from sight. With a huge number of high-quality pictorial documents, it is possible to reconstruct the LIA history of many glaciers in the European Alps from the 17th to the 19th centuries. Thanks to these pictures, we get an image of the beauty and fascination of LIA glaciers, ending down in the valleys. The pictorial documents (drawings, paintings, prints, photographs, and maps) of important artists (Caspar Wolf, Jean-Antoine Linck, Samuel Birmann) promoted a rapidly growing tourism. Compared with today’s situations, it gives totally different landscapes – a comparison of LIA images with the same views of today is probably the best visual proof for the changes in climate

The Glacier Views of Jean-Antoine Linck – A Milestone for the Mont Blanc Glacier History from the 18th to the 19

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 For example, historical documents have been used to reconstruct former glacier extents successfully at different sites, including in the well-documented Mont Blanc area that became popular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 reconstruire les fluctuations des glaciers au xixe siècle, au-delà du début des mesures systématiques. Par exemple, des documents historiques ont été appliqués pour reconstituer d’anciennes étendues des glaciers sur différents sites, notamment dans la région du Mont-Blanc, qui sont très bien documentés et devenus populaires parmi les artistes, les scientifiques et les voyageurs depuis le milieu du xviiie siècle. Le Genevois Jean-Antoine Linck est probablement l’artiste à qui l’on doit le plus de vues glaciaires exceptionnelles. La préférence particulière de Linck était les régions des glaciers, qu’il a découvertes et dessinées avec une audace d’alpiniste et une exactitude de naturaliste, principalement à la gouache, bien que de nombreux croquis au crayon aient été conservés. Linck a subtilement utilisé la technique de la gravure pour créer des planches de grand format facilement reproductibles, qui ont été ensuite coloriées à la gouache et à l’aquarelle. Cette technique lui a permis de créer de nombreuses reproductions d’une même vue, tout en leur donnant un aspect unique et original. Elles sont remarquables de sérénité et de silence, tout en offrant des ambiances lumineuses. Ces illustrations introduisent la représentation réaliste de la haute montagne dans l’iconographie de la peinture genevoise et conduisent ainsi à une nouvelle forme de peinture de paysage à caractère permanent. D’un point de vue de l’histoire des glaciers, et bien que nombre de ses œuvres ne soient pas exactement datées par l’auteur, l’ouvrage de Jean-Antoine Linck est indispensable. Il représente l’ensemble de l’évolution de la mer de Glace et du glacier des Bossons, mais également d’autres glaciers, pendant la période allant de la fin du xviiie siècle jusqu’au maximum glaciaire du xixe siècle vers 1820. L’œuvre de Linck accorde au territoire du Mont-Blanc la même importance, en termes d’iconographie des glaciers, que celle de Caspar Wolf et Samuel Birmann pour les Alpes centrales suisses, ou de Thomas Ender pour les Alpes autrichiennes. Linck était donc à la fois artiste et historien des glaciers

Glacier monitoring and capacity building: important ingredients for sustainable mountain development

Glacier observation data from major mountain regions of the world are key to improving our understanding of glacier changes: they deliver fundamental baseline information for climatological, hydrological, and hazard assessments. In many mountain ecosystems, as well as in the adjacent lowlands, glaciers play a crucial role in freshwater provision and regulation. This article first presents the state of the art on glacier monitoring and related strategies within the framework of the Global Terrestrial Network for Glaciers (GTN-G). Both in situ measurements of changes in glacier mass, volume, and length as well as remotely sensed data on glacier extents and changes over entire mountain ranges provide clear indications of climate change. Based on experiences from capacity-building activities undertaken in the Tropical Andes and Central Asia over the past years, we also review the state of the art on institutional capacity in these regions and make further recommendations for sustainable mountain development. The examples from Peru, Ecuador, Colombia, and Kyrgyzstan demonstrate that a sound understanding of measurement techniques and of the purpose of measurements is necessary for successful glacier monitoring. In addition, establishing durable institutions, capacity-building programs, and related funding is necessary to ensure that glacier monitoring is sustainable and maintained in the long term. Therefore, strengthening regional cooperation, collaborating with local scientists and institutions, and enhancing knowledge sharing and dialogue are envisaged within the GTN-G. Finally, glacier monitoring enhances the resilience of the populations that depend on water resources from glacierized mountains or that are affected by hazards related to glacier changes. We therefore suggest that glacier monitoring be included in the development of sustainable adaptation strategies in regions with glaciated mountains

Elevation changes of the Holm Land Ice Cap, northeast Greenland, from 1978 to 2012–2015, derived from high-resolution digital elevation models

Greenland’s peripheral glaciers and ice caps are key indicators of climate change in the Arctic, but quantitative observational data of their recent evolution are sparse. Three recently released high-resolution digital elevation models (DEMs)—AeroDEM (based on images from 1978 to 1987), ArcticDEM (2012–2015), and TanDEM-X (2010–2014)—provide the possibility to calculate elevation changes spanning almost four decades along the margins of the Greenland Ice Sheet. This study explores the potential of these DEMs by calculating elevation changes for the Holm Land Ice Cap (865 km2), northeast Greenland. Co-registration indicated no significant shifts between the DEMs but we encountered localized vertical offsets in AeroDEM. The data quality of ArcticDEM and TanDEM-X is high, but AeroDEM suffers from 19 percent low-quality data, which were treated as data voids. Applying two approaches to fill the data voids in the difference grid between ArcticDEM and AeroDEM, mean surface-elevation change over the Holm Land Ice Cap and a period of approximately 35 y is in the range of −8.30 ±0.30 m. Comparing ArcticDEM and TanDEM-X reveals a glacier elevation difference of 2.54 m, which may be partly related to the different retrieval techniques (optical and SAR). Overall, the DEMs have good potential for large-scale and long-term assessment of geodetic glacier mass balance

Democratizing glacier data – maturity of worldwide datasets and future ambitions

The creation and curation of environmental data present numerous challenges and rewards. In this study, we reflect on the increasing amount of freely available glacier data (inventories and changes), as well as on related demands by data providers, data users, and data repositories in-between. The amount of glacier data has increased significantly over the last two decades as remote sensing techniques have improved and free data access is much more common. The portfolio of observed parameters has increased as well, which presents new challenges for international data centers, and fosters new expectations from users. We focus here on the service of the Global Terrestrial Network for Glaciers (GTN-G) as the central organization for standardized data on glacier distribution and change. Within GTN-G, different glacier datasets are consolidated under one umbrella, and the glaciological community supports this service by actively contributing their datasets and by providing strategic guidance via an Advisory Board. To assess each GTN-G dataset, we present a maturity matrix and summarize achievements, challenges, and ambitions. The challenges and ambitions in the democratization of glacier data are discussed in more detail, as they are key to providing an even better service for glacier data in the future. Most challenges can only be overcome in a financially secure setting for data services and with the help of international standardization as, for example, provided by the CoreTrustSeal. Therefore, dedicated financial support for and organizational long-term commitment to certified data repositories build the basis for the successful democratization of data. In the field of glacier data, this balancing act has so far been successfully achieved through joint collaboration between data repository institutions, data providers, and data users. However, we also note an unequal allotment of funds for data creation and projects using the data, and data curation. Considering the importance of glacier data to answering numerous key societal questions (from local and regional water availability to global sea-level rise), this imbalance needs to be adjusted. In order to guarantee the continuation and success of GTN-G in the future, regular evaluations are required and adaptation measures have to be implemented

Vida y medios de subsistencia más seguros en las montañas: Cómo lograr que el Marco de Sendai para la Reducción del Riesgo de Desastres trabaje para el desarrollo sostenible de las regiones de montaña

Mountain systems are very diverse and so is the pattern of natural hazards. Worldwide disaster databases show that associated human and economic losses are significant but vary greatly between and within mountain regions. Continued changes in climate, land use and socio-economic conditions are likely to lead to vastly altered mountain landscapes in the future, with associated implications for hazards and impacts on sustainable mountain development

Last phase of the Little Ice Age forced by volcanic eruptions

During the first half of the nineteenth century, several large tropical volcanic eruptions occurred within less than three decades. The global climate effects of the 1815 Tambora eruption have been investigated, but those of an eruption in 1808 or 1809 whose source is unknown and the eruptions in the 1820s and 1830s have received less attention. Here we analyse the effect of the sequence of eruptions in observations, global three-dimensional climate field reconstructions and coupled climate model simulations. All the eruptions were followed by substantial drops of summer temperature over the Northern Hemisphere land areas. In addition to the direct radiative effect, which lasts 2–3 years, the simulated ocean–atmosphere heat exchange sustained cooling for several years after these eruptions, which affected the slow components of the climate system. Africa was hit by two decades of drought, global monsoons weakened and the tracks of low-pressure systems over the North Atlantic moved south. The low temperatures and increased precipitation in Europe triggered the last phase of the advance of Alpine glaciers. Only after the 1850s did the transition into the period of anthropogenic warming start. We conclude that the end of the Little Ice Age was marked by the recovery from a sequence of volcanic eruptions, which makes it difficult to define a single pre-industrial baseline

Reconstructing the annual mass balance of the Echaurren Norte glacier (Central Andes, 33.5° S) using local and regional hydroclimatic data

Despite the great number and variety of glaciers in southern South America, in situ glacier mass-balance records are extremely scarce and glacier–climate relationships are still poorly understood in this region. Here we use the longest (>  35 years) and most complete in situ mass-balance record, available for the Echaurren Norte glacier (ECH) in the Andes at  ∼  33.5° S, to develop a minimal glacier surface mass-balance model that relies on nearby monthly precipitation and air temperature data as forcing. This basic model is able to explain 78 % of the variance in the annual glacier mass- balance record over the 1978–2013 calibration period. An attribution assessment identified precipitation variability as the dominant forcing modulating annual mass balances at ECH, with temperature variations likely playing a secondary role. A regionally averaged series of mean annual streamflow records from both sides of the Andes between  ∼  30 and 37° S is then used to estimate, through simple linear regression, this glacier's annual mass-balance variations since 1909. The reconstruction model captures 68 % of the observed glacier mass-balance variability and shows three periods of sustained positive mass balances embedded in an overall negative trend over the past 105 years. The three periods of sustained positive mass balances (centered in the 1920s–1930s, in the 1980s and in the first decade of the 21st century) coincide with several documented glacier advances in this region. Similar trends observed in other shorter glacier mass-balance series suggest that the Echaurren Norte glacier reconstruction is representative of larger-scale conditions and could be useful for more detailed glaciological, hydrological and climatological assessments in this portion of the Andes

Historically unprecedented global glacier decline in the early 21st century

Observations show that glaciers around the world are in retreat and losing mass. Internationally coordinated for over a century, glacier monitoring activities provide an unprecedented dataset of glacier observations from ground, air and space. Glacier studies generally select specific parts of these datasets to obtain optimal assessments of the mass-balance data relating to the impact that glaciers exercise on global sea-level fluctuations or on regional runoff. In this study we provide an overview and analysis of the main observational datasets compiled by the World Glacier Monitoring Service (WGMS). The dataset on glacier front variations (⇠42 000 since 1600) delivers clear evidence that centennial glacier retreat is a global phenomenon. Intermittent readvance periods at regional and decadal scale are normally restricted to a subsample of glaciers and have not come close to achieving the maximum positions of the Little Ice Age (or Holocene). Glaciological and geodetic observations (⇠5200 since 1850) show that the rates of early 21st-century mass loss are without precedent on a global scale, at least for the time period observed and probably also for recorded history, as indicated also in reconstructions from written and illustrated documents. This strong imbalance implies that glaciers in many regions will very likely suffer further ice loss, even if climate remains stable

Global glacier mass changes and their contributions to sea-level rise from 1961 to 2016

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