Cryosphere

La mayor parte de la población de Perú se concentra en ciudades localizadas en la estrecha franja comprendida entre la costa del Océano Pacífico y los Andes Centrales. Se trata de una de las regiones más áridas de la Tierra, donde la precipitación total anual apenas alcanza unas decenas de mm. Por ese motivo las reservas hídricas de la población y sus actividades económicas dependen en gran medida de los glaciares que se conservan en la cordillera. Esas masas de hielo forman parte de la criosfera, junto con la nieve, los glaciares rocosos y las capas de suelo helado (permafrost), que también están adquiriendo gran importancia como reservas de agua debido a la marcada tendencia a la reducción de la superficie y el volumen de los glaciares observada durante las últimas décadas. El proceso de deglaciación implica además un incremento de los peligros geológicos asociados a la criosfera, como aludes, avalanchas y otros tipos de movimientos en masa. El riesgo es mayor si cabe en las vertientes de la cordillera como consecuencia de su fuerte desnivel. En ese contexto la Autoridad Nacional del Agua (ANA); el Instituto Geológico Minero y Metalúrgico (INGEMMET); el Grupo de Investigación en Geografía Física de Alta Montaña de la Universidad Complutense de Madrid (GFAM) y la ONG Guías de Espeleología y Montaña (GEM), con el auspicio de la Organización de las Naciones Unidas para la Educación, la Ciencia y la Cultura (UNESCO), han acordado impulsar un proyecto denominado CRYOPERU, con dos metas principales: 1) Contribuir a la comprensión de los efectos del cambio climático en la criosfera de los Andes Centrales, en relación con dos problemas que afectan a Perú: la reducción de las reservas hídricas sólidas y el incremento de los peligros geológicos asociados al proceso de deglaciación. 2) Proporcionar instrumentos de análisis a las instituciones que deben planificar y ejecutar las políticas de adaptación y mitigación de la sociedad a los efectos del cambio climático. Para alcanzar los objetivos previstos el proyecto analizará 10 geoindicadores del cambio climático y 4 geoindicadores de peligros geológicos en 8 áreas de estudio distribuidas de norte a sur de la cordillera occidental y la cordillera oriental de los Andes Centrales. Se ha previsto el desarrollo de un software para automatizar, sistematizar y recopilar los resultados. El software será la plataforma tecnológica online de un Observatorio de la Criosfera.

The cryosphere provides multiple services to society, but mountain cryosphere is shrinking at an alarming rate worldwide due to climate change, threatening natural and human systems. Adaptation to cryosphere change is essential to avoid irreversible damage and to achieve the Sustainable Development Goals. Although documenting adaptation actions and challenges is vital for preparing and implementing adaptation strategies, efforts to document and understand current adaptation practices specifically in response to cryosphere change have been limited. This paper synthesizes adaptation actions currently practiced in the mountain ranges of the Andes, Alps, Pamir, Tien Shan and Himalaya in response to cryosphere change, discusses common constraints and suggests actions for creating an enabling environment for adaptation. It identifies various adaptation measures adopted by different actors. These range from changing current practices and behaviour at household level to collaborative monitoring at regional level. However, most adaptation measures are autonomous, narrowly focused and short term, without adequate planning and government support. The physical challenges of mountain terrain, low adaptive capacities, limited knowledge and high uncertainty about future risks constrain widespread adoption of adaptation measures. Further research is needed to better understand factors influencing adaptation actions, and the policy options and responses that can overcome existing barriers. ARTICLE HISTORY

This work provides an overview of various methods for estimating snow cover and properties in high mountains using remote sensing techniques involving microwaves. Satellite based remote sensing with its characteristics such as synoptic view, repetitive coverage and uniformity over large areas, has great potential for identifying the temporal snow cover. Many sensors have been used in the past with various algorithms and accuracies for this purpose. These methods have been improving with the use of Synthetic Aperture Radar (SAR) sensors, working in different microwave frequencies, polarization and acquisition modes. The limitations, advantages and drawbacks are illustrated while error sources and strategies on how to ease their impacts are also reviewed. An extensive list of references, with an emphasis on studies since 1990s, allows the reader to delve into specific topics.

This paper analyzes the evolution of the Monte Perdido Glacier, the third largest glacier in the Pyrenees, from 1981 to the present. We assessed the evolution of the glacier's surface area by analysis of aerial photographs from 1981, 1999, and 2006, and changes in ice volume by geode-tic methods with digital elevation models (DEMs) generated from topographic maps (1981 and 1999), airborne li-dar (2010) and terrestrial laser scanning (TLS, 2011, 2012, 2013, and 2014) data. We interpreted the changes in the glacier based on climate data from nearby meteorological stations. The results indicate that the degradation of this glacier accelerated after 1999. The rate of ice surface loss was almost three times greater during 1999–2006 than during earlier periods. Moreover, the rate of glacier thinning was 1.85 times faster during 1999–2010 (rate of surface elevation change = −8.98 ± 1.80 m, glacier-wide mass balance = −0.73 ± 0.14 m w.e. yr −1) than during 1981–1999 (rate of surface elevation change = −8.35 ± 2.12 m, glacier-wide mass balance = −0.42 ± 0.10 m w.e.

In the context of a general retreat of glaciers in the dry Andes, this study focuses on the state and recent evolution of debris-covered glaciers and permafrost-related landforms, especially rock glaciers, in the semiarid to semihumid Laguna Negra catchment, a part of the Andes of central Chile at 33.5°S, that is a key contributor of drinking water for the city of Santiago. We conducted catchment-scale geomorphological mapping, diachronic analysis of 1955 and 1996 orthophotographs and digital elevation models (DEMs), and the analysis of ground temperatures and their sensitivity to climate variation. Rock glaciers dominate spatially and in terms of water storage over glaciers (area ratio: 1.7:1; ratio of water equivalents: 1.5:1). An intense downwasting has affected both debris-covered and exposed glacier components in the Punta Negra subcatchment, a process that is associated with the growth of numerous thermokarst depressions. The altitudinal transect of ground temperature suggest that permafrost is widespread above ∼4000 m asl, although it can also occur at lower elevations on sheltered footslopes and within rock glaciers. The sensitivity analysis indicates that the near-surface ground thermal regime at high altitudes is strongly influenced by the snow cover disappearance date, which may therefore constitute an important control on the effect of climatic warming.

Continental slopes north of the East Siberian Sea potentially hold large amounts of methane (CH4) in sediments as gas hydrate and free gas. Although release of this CH4 to the ocean and atmosphere has become a topic of discussion, the region remains sparingly explored. Here we
present pore water chemistry results from 32 sediment cores taken during Leg 2 of the 2014 joint Swedish–Russian–US Arctic Ocean Investigation of Climate–Cryosphere–Carbon Interactions (SWERUS-C3) expedition. The cores come from depth transects across the slope and rise extending between the Mendeleev and the Lomonosov ridges, north of Wrangel Island and the New Siberian Islands, respectively.
Upward CH4 flux towards the seafloor, as inferred from profiles of dissolved sulfate (SO42-), alkalinity, and the 13C of dissolved inorganic carbon (DIC), is negligible at all stations east of 143 E longitude. In the upper 8m of these cores, downward SO42- flux never exceeds
6.2 mol m-2 kyr-1, the upward alkalinity flux never exceeds 6.8 mol m-2 kyr-1, and 13C composition of DIC (13CDIC) only moderately decreases with depth (3.6‰ m-1 on average). Moreover, upon addition of Zn acetate to pore water samples, ZnS did not precipitate, indicating a lack of dissolved H2S. Phosphate, ammonium, and metal profiles reveal
that metal oxide reduction by organic carbon dominates the geochemical environment and supports very low organic carbon turnover rates. A single core on the Lomonosov Ridge differs, as diffusive fluxes for SO42- and alkalinity were 13.9 and 11.3 mol m-2 kyr-1, respectively, the 13C-DIC gradient was 5.6‰ m-1, and Mn2+ reduction terminated within 1.3m of the seafloor. These are among the first pore water results generated from this vast climatically sensitive region, and they imply that abundant CH4, including gas hydrates, do
not characterize the East Siberian Sea slope or rise along the investigated depth transects. This contradicts previous modeling and discussions, which due to the lack of data are almost entirely based on assumption.

In recent years airborne and spaceborne remote sensing have developed into a widely applied tool for archaeologists. In glacial archaeology, it has been employed successfully, but could see a wider application among practitioners. This article summarizes common remote sensing approaches useful to archaeologists in cryogenic environments. It covers simple applications using easily accessible data in order to enable the practitioner to monitor melt and contextualize archaeological sites within a larger landscape setting. The improved resolution and availability of remote sensing data enhances its usefulness with regards to identifying, documenting and monitoring sites in frozen environments and is a valuable addition to most field research pertaining to glacial archaeology.

This article reviews the COP 21 agreement on climate mitigation, explains why it is doomed to fail without systemic transformation, and proposes a method for accelerating the evolution of a sustainable global system.
Despite the achievements of the Paris Agreement, the world is still racing towards disaster. This is because it will not be possible to preserve critical ecosystems without placing internationally enforceable limits on both pollution and consumption—tasks that are not possible within current economic and political frameworks.
This dichotomy—between the need to work within existing institutions and the reality that they are structurally incapable of preventing catastrophic outcomes—may be resolved by using a holistic, three-track approach.  The first track will reframe and intensify climate mitigation efforts. The second track will challenge the ideological opposition to climate mitigation. The third track will help catalyse the global movement needed to empower structural transformation and the emergence of a sustainable global system.

This paper describes anchor ice formation in the Laramie River, a small river in Wyoming. Anchor ice in the Laramie River forms predominately in riffles at night, although minor amounts also form on sand substrates. Anchor ice crystals are large, indicating that in situ thermal growth is important. Anchor ice forms on the river’s bed, and, when released from the bed, rafts bed sediment downstream. The floating, released anchor ice is a major contributor to the river’s surface ice cover. A conceptual model for anchor ice formation is developed. This model suggests that water supercooled in pools supplies a heat sink that absorbs the latent heat of fusion of anchor ice growing in riffles. The net result is a non-uniform distribution of anchor ice on the bed. We discuss flow parameters important for determining anchor ice growth, and show how a substantial set of parameters influence anchor ice formation.

Archaeologists worldwide know very little about the immense ecosystem changes already underway in the mountains and the threats that anthropogenic climate change poses to high elevation cultural resources. So how do we proceed? What do we prioritize? Is high elevation ice resilient to these changing climates, and if so, how much? How much time do we have before mid-latitude high elevation ice disappears entirely? This paper comments on the impacts of climate change to high elevation cultural resources, particularly ice patches, whose presence as a constant source of water is vital to the general appeal of high elevations for human occupation. Beyond their ecological importance, ice patches can also preserve ancient organic artifacts and paleobiological material for over 10,000 years. And they are melting rapidly thanks to anthropogenic climate change. This paper offers a case study of two groups of archaeologically productive high elevation ice patches from the Greater Yellowstone Ecosystem, analyzing their resiliency in the face of warming temperatures and changing climates. Ultimately, I conclude that high elevation patches of ice and snow may be losing their resiliency to warmer temperatures as their ancient ice melts, making them ever more vulnerable to climate change. Ice patch researchers are in a race against time to identify productive ice patches and recover any fragile artifacts or paleobiological material they may contain before they melt completely. For many of these patches, this would be their first complete melt since the early Holocene.

Transboundary river basins provide inhabitance and water resources to millions of people
around the globe and they are a source of dispute among neighbor countries also. This thesis
focuses on the snow melt and runoff modeling of a small transboundary river, Talas; using a
physically distributed rainfall-runoff model, TOPKAPI-ETH. Investigation on the use of
remotely sensed precipitation estimates and MODIS snow cover images shows that they can be
a key to model snowmelt and water resources of remote and un-gauged catchments. However
the need of observed precipitation data from different regions and elevation zones of the basin
is vital in generating the runoff with higher accuracy. Annual runoff prediction strategies from
snow cover area is also proposed which can be of great help in efficient management of water
resources and hence in resolving conflict between the riparian countries, Kyrgyzstan and
Kazakhstan.

As the ice of the world melts, heat is made visible. Rapidly rising temperatures draw attention to Earth's cryosphere as it is increasingly measured, its retreats photographed, its depths plumbed and its duration calculated. Lost glaciers and cracked ice sheets demonstrate changes to cryoforms but they can also be taken as allegories of the ways that human labor has been performed with, or upon, nature. In the minor time of human existence, labor has carved into ecological systems, indexing the work that has gone into them as well as what has been extracted from them.

A warming climate is melting the namesake glaciers of Glacier National Park, Montana, USA. James Dyson's 1948 paper was one of the earliest publications to emphasize climate change impacts to the cryosphere through an examination of Sperry and Grinnell Glaciers. This paper, combined with his subsequent works, acts as a pillar for current glacier monitoring efforts.

The Little Ice Age maximum extent of glaciers in Iceland was reached about 1890 AD and most glaciers in the country have retreated during the 20th century. A model for the surface mass balance and the flow of glaciers is used to reconstruct the 20th century retreat history of Hoffellsjökull, a south-flowing outlet glacier of Vatnajökull, which is located close to the southeast coast of Iceland. The bedrock topography was surveyed with radio-echo soundings in 2001. A wealth of data are available to force and constrain the model, e.g. surface elevation maps from ~1890, 1936, 1946, 1986, 2001, 2008 and 2010, mass balance observations conducted in 1936-1938 and after 2001, energy balance measurements after 2001, and glacier surface velocity derived by DGPS and correlation of SPOT5 images. The 21% volume loss of this glacier in the period 1895-2010 is realistically simulated with the model. After calibration of the model with past observations, it is used to simulate the future response of the glacier during the 21st century. The mass balance model was forced with an ensemble of temperature and precipitation scenarios from a study of the effect of climate change on energy production in the Nordic countries (the CES project). If the average climate of 2000-2009 is maintained into the future, the volume of the glacier is projected to be reduced by 30% with respect to the present at the end of this century, and the glacier will almost disappear if the climate warms as suggested by most of the climate change scenarios. Runoff from the glacier is predicted to increase for the next 30-40 years and decrease after that as a consequence of the diminishing ice-covered area.

Cryogenic mineral formations were studied in the Askinskaya Ice Cave, situated on the Southern Ural within Bashkortostan. Investigation of the morphology and elemental composition of cryogenic mineral formations was carried out using a scanning electron microscope (SEM) and by energy-dispersive X-ray spectroscopy (EDXA). Diagnosis of the mineral composition of the samples was carried out using X-ray diffractometry. Calcite is the predominant mineral of the cryogenic suite, with an insignificant admixture of presumably hydrated magnesium carbonates. It is concluded that the cryogenic mineral deposits in the Askinskaya cave owe their genesis to at least two basic mechanisms: 1) crystallization within the freezing film of water on the ice surface, which is the most common mechanism both in the Askinskaya cave and in other ice caves and 2) crystallization inside the fluid inclusions within the ice. This second mechanism is rarely discussed for cave conditions but is known from model experiments on freezing aqueous solutions. There are signs of post-cryogenic transformation of deposits, consisting of agglomerations of primary microcrystalline cryogenic carbonates, with the addition of a new generation of calcite with morphology typical of low supersaturations.

Meltwater from glaciers makes significant contributions to general streamflow and provides water for flora and fauna. Continuous glacier monitoring programs enhance our understanding of the impacts of global warming on glaciers and their topographical features. The objective of this study is to measure spatial and temporal changes in Canada’s Columbia Icefield glaciers. This study uses Landsat (TM 5 and OLI) images to delineate glacier extents in the Columbia Icefield between 1985 and 2018. The study also analyzes the retreat of the Athabasca, Castleguard, Columbia, Dome, Saskatchewan, and Stutfield Glaciers. The total area covered by the Icefield in 1985 was 227 km2. By 2018, the Icefield had lost approximately 42 km2 of its area coverage, representing 18% of its previous coverage. All glaciers in the study region retreated and decreased in area over the study period. The pattern observed in this study is one of general ice loss in the Columbia Icefield, which mirrors patterns obse...

Maritime Antarctica has shown the highest increase in temperature in the Southern Hemisphere. Under this scenario, biogeochemical cycles may be altered, resulting in rapid environmental change for Antarctic biota. Microbes, that drive biogeochemical cycles often form biofilms or microbial mats in continental meltwater environments. Limnetic microbial mats from the Fildes Peninsula were studied using high-throughput 16S rRNA gene sequencing. Mat samples were collected from fifteen meltwater stream sites, comprising a natural gradient from ultraoligotrophic glacier flows to meltwater streams exposed to anthropogenic activities. Our analyses show microbial structure differences between mats are explained by environmental NH 4 + , NO 3-, DIN, soluble reactive silicon and conductivity. Microbial mats living under ultraoligotrophic meltwater conditions did not exhibit a dominance of cyanobacterial photoautotrophs, as it has been Downloaded from https://academic.oup.com/femsec/advance-article-abstract/doi/10.1093/femsec/fiy129/5047302 by

Antarctic climate changes have been reconstructed from ice and sediment cores and numerical models (which also predict future changes). Major ice sheets first appeared 34 million years ago (Ma) and fluctuated throughout the Oligocene, with an overall cooling trend. Ice volume more than doubled at the Oligocene-Miocene boundary. Fluctuating Miocene temperatures peaked at 17–14 Ma, followed by dramatic cooling. Cooling continued through the Pliocene and Pleistocene, with another major glacial expansion at 3–2 Ma. Several interacting drivers control Antarctic climate. On timescales of 10,000–100,000 years, insolation varies with orbital cycles, causing periodic climate variations. Opening of Southern Ocean gateways produced a circumpolar current that thermally isolated Antarctica. Declining atmospheric CO 2 triggered Cenozoic glaciation. Antarctic glaciations affect global climate by lowering sea level, intensifying atmospheric circulation, and increasing planetary albedo. Ice sheets interact with ocean water, forming water masses that play a key role in global ocean circulation.

In this paper, we estimate the contribution of snowdrift sublimation (SUds) to the surface mass balance at Neumayer, located on the Ekström ice shelf in Eastern Antarctica. A single column version of the RACMO2-ANT model is used as a physical interpolation tool of high-quality radiosonde and surface measurements for a 15-yr period (1993–2007), and combined with a routine to calculate

The authors of the article have made an attempt to consider the role of natural cryogenic resources (snow, ice, permafrost, etc.) in traditional subsistence systems of the peoples of Siberia and the Far East. The integrating role in the methodology of the research belongs to ethnoecology which studies regularities of interactions of people and nature within various traditional cultures. More than 65% of the territory of the Russian Federation is situated in the cryolithozone, the top layer of the Earth’s crust with frozen formations. Its top part (permafrost and reservoir ices) is an environment formation component of a territorial resource which provides stability of landscapes suitable for people’s life. The authors give examples of how changes of cryogenic conditions (snow covers, freezing or thawing of permafrost and reservoirs) directly influence the functioning of traditional subsistence systems in different peoples. The authors, using ethnographic descriptions of the second half of the 19th – the beginning of the 21st centuries and their own field research data, have considered the traditional ecological knowledge of the peoples of Siberia and the Far East related to the use of natural cryogenic resources as a construction material, for food storage, for receiving moisture for drinking and irrigation of crops in agriculture and in some other spheres of economic activity. In the conclusion of the article the authors allocate the perspective directions of research of the role of natural cryogenic resources in traditional subsistence systems. The first of them is related to
the study of the anthropogenous aspects of cryodiversity inherent to some traditional cultures. According to the authors, ethnolinguistic studies of specific words and concepts which have developed in languages of the peoples inhabiting the territory of the Arctic and the Subarctic region and reflect various transformations or specific practical meanings people give to cryogenic objects have a big importance. The second direction has to give answers about how critical the natural cryogenic resource is for functioning of a traditional subsistence system of a certain local community. The third important direction of research is the search for a possible adaptation of the traditional ecological knowledge which has developed in some ethnic cultures to modern developments in the sphere of
innovative economic activity. The authors make a conclusion that the experience which has developed for centuries is extremely important both for the survival of some local communities conducting traditional kinds of subsistence and for the solution of some innovative tasks connected with the rational use of natural and energy resources.