Water bears dominated cryoconite hole ecosystems: densities, habitat preferences and physiological adaptations of Tardigrada on an alpine glacier

We investigated the Forni Glacier and the surrounding area in the Alps in terms of habitat preferences, densities, dispersal and desiccation tolerance of glacier tardigrades, which are one of the most common faunal representatives and top consumers in supraglacial ecosystems. To do so, we sampled supraglacial environments (cryoconite holes, debris from ice surface, dirt cones and moraine, mosses from supraglacial stones) and non-glacial habitats (mosses, freshwater sediments and algae), and we installed air traps on the glacier and the nearby area. We found that cryoconite holes on the Forni Glacier are exclusively dominated by one metazoan group of tardigrades, representing one species, Hypsibius klebelsbergi (identified by morphological and molecular approaches). Tardigrades were found in 100% of cryoconite holes and wet supraglacial sediment samples and reached up to 172 ind./ml. Additionally, we found glacier tardigrades in debris from dirt cones and sparsely in supraglacial mosses. Glacier tardigrades were absent from freshwater and terrestrial samples collected from non-glacial habitats. Despite the fact that H. klebelsbergi is a typical aquatic species, we showed it withstands desiccation in sediments, but in low temperatures only. Treatments conducted in higher temperatures and water only showed low or no recovery. We suspect successful dispersal with wind might have taken place only when tardigrades desiccated in sediments and were passively transported by cold wind. Limited ability to withstand high temperatures and desiccation may be potential barriers preventing glacier tardigrades inhabiting new, even apparently suitable high mountain water bodies like temporary rock pools

PRELIMINARY MAPPING OF GLACIERS AND GLACIAL LANDFORMS OF MOUNT AĞRI DAĞI (ARARAT), EASTERN ANATOLIA - TURKEY

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Geomorphology of Mount Ararat/Ağri Daği (Ağri Daği Milli Parki, Eastern Anatolia, Turkey)

This paper presents a geomorphological map of Mount Ararat/Ağri Daği in Eastern Anatolia (Turkey). Mount Ararat/Ağri Daği is a volcanic complex covered by a unique ice cap in the Near East. The massif is the result of multiple volcanic phases, and present day landforms are the result of subsequent and overlapping glacial, periglacial, and slope processes. The geomorphological mapping of Mount Ararat/Ağri Daği was firstly performed on the basis of desktop studies, by applying remote-sensing investigations using high-resolution satellite imagery (PLEIADES and SPOT images). A preliminary draft of the map was crosschecked and validated in the field as part of an interdisciplinary campaign carried out in the 2014 summer season. All the collected data suggest that the Mount Ararat/Ağri Daği glaciation played a crucial role in the evolution of the landscape and that even today glaciers are significant features in this area. Currently, ice bodies cover 7.28 km2 and include peculiar glacier types. Among these are three well-developed debris-covered glaciers, flowing down along the flanks of the volcano

Variations of Lys Glacier (Monte Rosa Massif, Italy) from the Little Ice Age to the Present from Historical and Remote Sensing Datasets

Alpine glaciers respond to climate imbalance by adjusting their mass and length. In turn, these changes modify the glacial and periglacial environment, leading to increased supraglacial debris cover, the development of glacial lakes and glacier fragmentation. In this research, we investigated the evolution of Lys Glacier (Monte Rosa Group), by studying length, area and volume changes, and evolution of its supraglacial debris cover and proglacial lakes by means of historical sources and high-resolution aerial and satellite orthophotos. Lys Glacier retreated almost continuously, by nearly 2 km, from its maximum Little Ice Age position. More recently, the glacier lost 11.91% of its area between 1975 and 2014 and underwent fragmentation in 2009. Over the same period, glacier fragmentation and tongue stagnation affected the formation and rapid growth of a series of ice-contact lakes and led to a non-linear debris cover evolution. The glacier was also subjected to strong volume losses, with more than 135 m thinning on the ablation tongue from 1991 to 2014. Analysis of the meteorological records (1927–present) from the closest weather station reveals a considerable increase in average annual temperatures by more than 1°C from the mean of 1971–1989 to the mean of 1990–2017

Snow data intercomparison on remote and glacierized high elevation areas (Forni Glacier, Italy)

Abstract. We present and compare 11 years of snow data (snowfall, snow depth and snow water equivalent (SWE)) measured by an Automatic Weather Station and by some field campaigns on the Forni Glacier. The data have been acquired by means of (i) a Campbell SR50 sonic ranger from October 2005 (snow depth data), (ii) manual snow pits from January 2006 (snow depth and SWE data), (iii) a Sommer USH8 sonic ranger from May 2014 (snow depth data), (iv) a Park Mechanical SS-6048 snow pillow from May 2014 (SWE data), (v) a manual snow weighting tube (Enel-Valtecne©) from May 2014 (snow depth and SWE data). The aim of the analyses is to assess the mean value of fresh snow density and the most appropriate method to evaluate SWE for this measuring site. The results indicate that the daily SR50 sonic ranger measures allow a rather good estimation of the SWE, and the provided snow pit data are available for defining the site mean value of fresh snow density. For the Forni Glacier measuring site, this value turned out to be 140 kg m−3. The SWE derived from sonic ranger data is rather sensitive to this value: a change in fresh snow density of 20 kg m−3 causes a mean variation in SWE of ±0.093 m w.e. for each hydrological year, ranging from ±0.050 m w.e. to ±0.115 m w.e

Inventory of glaciers and glacial lakes of the Central Karakoram National Park (CKNP – Pakistan)

This study presents a map reporting valuable information on the cryosphere of the Central Karakoram National Park (CKNP, the largest protected area of Pakistan and the highest park in the world). All the information is provided considering the CKNP as a whole, and in detail by dividing it into five basins (i.e. Shigar, Hunza, Shyok, Upper Indus, and Gilgit). The glacier inventory reports 608 ice bodies covering 3680 km2 ( 3c35% of the CKNP area), with a total glacier volume of ca. 532 km3. In addition, we modeled the meltwater from glacier ice ablation over the period 23 July to 9 August 2011. The total melt amount is ca. 1.5 km3. Finally, we considered glacial lakes (202 water-bodies, covering 4 km2). For these latter glacier features, we also analyzed their potentially dangerous conditions and two lakes were found having such conditions

Inventory of glaciers and glacial lakes of the central Karakoram National Park (Pakistan) as a contribution to know and manage mountain freshwater resource.

In this study, we reported valuable information on the cryosphere of the Central Karakoram National Park (CKNP, the largest protected area of Pakistan and the highest park all over the world). In fact, in addition to the glacier inventory, we also estimated the glacier volume and we modeled the amount of meltwater derived from glacier ice ablation during a 18-day summer period (23 July–9 August 2011, time window where also field melt measurements were performed thus enabling a crosscheck of the obtained results). Moreover, glacial lakes were considered as well; for these latter glacier features we also analyzed their potentially dangerous conditions. All these information are given considering the CKNP as a whole and in detail by dividing it into five basins (i.e. Shigar, Hunza, Shyok, Upper Indus and Gilgit). As regards the CKNP as a whole, 608 glaciers are found with a total area of 3682.1 ± 61.0 km2, ~35% of the CKNP area. Analyzing in detail the five basins included in the CKNP area, they reflect the overall conditions regarding glacier distribution per size class, terminus elevation, length, and thickness. The widest basin (for number of ice bodies, glacier extent and ice volume) is the Shigar basin, where the largest glaciers are present (among which Baltoro Glacier), and the smallest one is the Gilgit basin. Finally, the highest number of debris-covered glaciers is located in the Shyok basin (62 glaciers). During 18 days in summer 2011, we quantified a total water magnitude of 1.54 km3 derived from ice melting. Even if we considered a relatively short period, this water volume equals ~11% of the reservoir capacity of the Tarbela Dam. In addition to glacier information, we provided glacial lake occurrence, as these ephemeral water bodies can develop into actual glacial risk conditions, which makes it important to list them and to survey them over time. The information reported in this study would provide base for future monitoring of glacial lakes and GLOFs and for planning and prioritizing disaster mitigation efforts in the park. In fact, even if the Potentially Dangerous Glacial Lakes (PDGLs) identified in the park territory are only 2, they are located in a high vulnerable and fragile area and the recent history suggests us to survey over time these water bodies to avoid losses of human lives and destructions of villages and communities. Moreover, many other supraglacial lakes identified in the park area could develop into conditions of PDGLs thus suggesting to prosecute the lake monitoring and to develop early strategies for risk mitigations and disaster management