28,370 results on '"Glacier"'
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2. Estimating glacier dynamics and supraglacial lakes together with associated regional hazards using high-resolution datasets in Pamir.
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Safarov, Mustafo, Kang, Shichang, Fazylov, Ali, Gulayozov, Majid, Banerjee, Abhishek, Navruzshoev, Hofiz, Chen, Pengfei, Xue, Yuang, and Murodov, Murodkhudzha
- Abstract
Recent climate dynamics denote patterns and variations in climatic conditions and associated cryospheric changes in the Pamir region, affecting downstream ecosystems and communities. The present investigation describes changes in Baralmos glacier and supraglacial lakes, along with related hazards, using meteorological observations, reanalysis products, and high-resolution satellite imagery from 2002 to 2022. Moreover, observations using Unmanned Aerial Vehicles (UAVs) were conducted between 2020 and 2022 to document recent variations. Reanalysis data suggested that there are no obvious trends in annual air temperature and precipitation except for a significant temperature rise in July (the warmest month) of about 1.34°C/decade (p<0.05) and precipitation decrease in December (p<0.05). During the last two decades of investigation, lake areas expanded from 20500 to 62800 ± 21 m
2 , representing an approximately threefold increase, leading to increased mudflows in the Surkhob river and causing severe damage to property and infrastructures, most prominently during 2020 and 2022. The UAV data reveal an average decrease of −2.7 ± 0.5 m in surface elevation downstream of Baralmos glacier between 2020 and 2022. This study is vital for implementing more intensive measures of the glacial environment and defining suitable mitigation strategies in the Pamir region. [ABSTRACT FROM AUTHOR]- Published
- 2024
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3. Narwhal (Monodon monoceros) associations with Greenland summer meltwater release.
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Laidre, Kristin L., Zahn, Marie J., Simon, Malene, Ladegaard, Michael, Stafford, Kathleen M., Phillips, Elizabeth, Moon, Twila, Stern, Harry L., and Cohen, Benjamin
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GREENLAND ice ,HEAT waves (Meteorology) ,NARWHAL ,SEA ice ,ICE sheets ,MELTWATER - Abstract
Climate change is rapidly transforming the coastal margins of Greenland. At the same time, there is increasing recognition that marine‐terminating glaciers provide unique and critical habitats to ice‐associated top predators. We investigated the connection between a top predator occupying glacial fjord systems in Northwest Greenland and the properties of Atlantic‐origin water and marine‐terminating glaciers through a multiyear interdisciplinary project. Using passive acoustic monitoring, we quantified the summer presence and autumn departure of narwhals (Monodon monoceros) at glacier fronts in Melville Bay and modeled what glacier fjord physical attributes are associated with narwhal occurrence. We found that narwhals are present at glacier fronts after Greenland Ice Sheet peak summer runoff and they remain there during the period when the water column is becoming colder and fresher. Narwhals occupied glacier fronts when ocean temperatures ranged from −0.6 to 0.8°C and salinities between 33.2 and 34.0 psu at around 200 m depth and they departed on their southbound migration between October and November. Narwhals' departure was approximately 4 weeks later in 2019 than in 2018, after an extreme 2019 summer heatwave event that also delayed sea ice formation by 2 months. Our study provides further support for the niche conservative narwhal's preference for cold ocean temperatures. These results may inform projections about how future changes will impact narwhal subpopulations, especially those occupying Greenland glacial fjords. [ABSTRACT FROM AUTHOR]
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- 2024
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4. How can geomorphology facilitate a better understanding of glacier and ice sheet behaviour?
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Jones, Richard S., Miller, Lauren E., and Westoby, Matthew J.
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GLACIOLOGY ,ICE sheets ,GLACIAL climates ,LANDFORMS ,REMOTE sensing ,GLACIERS ,GEOMORPHOLOGY - Abstract
Glaciers and ice sheets are an integral part of Earth's system, advancing and retreating in response to changes in climate. Clues about the past, present and future behaviour of these ice masses are found throughout current and former glaciated landscapes. In this commentary, we outline recent scientific advances from a collection of articles in which geomorphological evidence is used to inform us about the behaviour of glaciers and ice sheets across a range of spatial (landform to continent) and temporal (seasons to millennia) scales. Through a diversity of approaches including field measurements, remote sensing and numerical modelling, these studies build on an extensive background literature to deepen our understanding of how ice flows, how glaciers and ice sheets respond to climate change, and of the processes of ice advance and retreat and the stability of the system. Further integration of knowledge across the fields of geomorphology and glaciology will have tangible benefits for managing the societal and environmental impacts of glacier change and for improved projections of sea‐level rise over the coming decades to centuries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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5. Emerging glacier forelands alter carbon dynamics on the Tibetan Plateau.
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Gao, Tanguang, Zhang, Yulan, and Meadows, Michael Edward
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GLOBAL warming ,ATMOSPHERIC carbon dioxide ,DISSOLVED organic matter ,GLACIAL lakes ,CLIMATE change - Abstract
The critical challenge of ongoing climate warming is resulting in glacier melting globally, a process accompanied by the formation of substantial glacier forelands. This phenomenon emerges as a pivotal area of study, especially in the Tibetan Plateau (TP), known as the Third Pole and the Asian Water Tower. In particular, the rapid retreat of temperate glaciers in the southeastern TP has led to the formation of expansive glacier forelands. These forelands are not merely evidence of climate shifts but are also key areas for transformative carbon dynamics. Moreover, the newly exposed land surface actively adjusts the balance of dissolved organic carbon, especially in meltwater, and influences the release of greenhouse gases from a range of sources including glacial lakes, subglacial sediments, and supraglacial/proglacial rivers. These processes play a crucial role in the dynamics of atmospheric carbon dioxide. Drawing from our intensive and detailed observations over several years, this perspective not only emphasizes the importance of the underexplored impact of glacier forelands on carbon cycles but also opens a window into understanding potential future trajectories in a warming world. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Spatial and temporal changes of glaciers and glacial lakes in the Northern Tianshan Mountains over the past 30 years.
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Hu, Jiayu, Yao, Xiaojun, Zhang, Cong, Zhang, Yuan, and Ma, Yuxin
- Abstract
Glaciers and glacial lakes are very sensitive to climate change, and studying their dynamics is important for revealing changes in global climate. In this study, we extracted the boundaries of glaciers and glacial lakes in the Northern Tianshan Mountains based on Landsat TM/ETM+/OLI and Sentinel 2A/2B MSI remote sensing images and analyzed their dynamics and impacts over the past 30 years. The findings indicate that in 2020, the Northern Tianshan region exhibited a total of 3254 glaciers, with an area of 1670.55 km
2 and a volume of 95.69 km3 . The corresponding numbers, areas, and volumes of glacial lakes were 281, 13.23 km2 and 210.49×106 m3 , respectively. Over the past 30 years, glaciers and glacial lakes have exhibited opposite characteristics. The former decreased by 16, 332.64 km2 (−0.60%·a−1 ) and 18.36 km3 (−0.58%·a−1 ), respectively, and the latter increased by 56 and 2.48 km2 (0.82%·a−1 ) and 38.88×106 m3 (0.79%·a−1 ), respectively. Moreover, different glacier termination types cause differences in the glacier retreat rates. Lake-terminated glaciers retreated faster than land-terminated glaciers, and the type of glacier termination has a greater effect on the retreat rate than the size of the glacial area. [ABSTRACT FROM AUTHOR]- Published
- 2024
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7. Mitigation of black carbon emissions could immediately reduce 6.3% of glacier melting in the Qilian Mountains
- Author
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Ji-Zu Chen, Wen-Tao Du, Shi-Chang Kang, Xiang Qin, Wei-Jun Sun, Li-Hui Luo, Yang Li, Jun-Hua Yang, and You-Yan Jiang
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Glacier ,Melting ,Black carbon ,Simulation ,Qilian Mountains ,Meteorology. Climatology ,QC851-999 ,Social sciences (General) ,H1-99 - Abstract
Global warming in tandem with surface albedo reduction caused by black carbon (BC) deposition on glaciers accelerated glacier melting; however, their respective contributions remain unclear. Glaciers in the Qilian Mountains are crucial for the development of oases in the Hexi Corridor; however, their area has decreased by more than 20% over the past half-century. Thus, this study developed a dynamic deposition model for light-absorbing particles (LAPs), coupled with a surface energy and mass balance model. We comprehensively assessed the effects of BC and warming on the melting of a typical glacier in the Qilian Mountains based on the coupled model. BC on the glacier surface caused 13.1% of annual glacier-wide melting, of which directly deposited atmospheric BC reduced the surface albedo by 0.02 and accounted for 9.1% of glacier melting. The air temperature during 2000–2010 has increased by 1.5 °C relative to that during the 1950s, accounting for 51.9% of current glacier melting. Meanwhile, BC emission have increased by 4.6 times compared to those of the early Industrial Revolution recorded in an ice core, accounting conservatively for 6.3% of current glacier melting. Mitigating BC emissions has a limited influence on current glacier melting; however, in the long-term, mitigation should exert a noteworthy impact on glacier melting through the self-purification of glaciers.
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- 2024
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8. Acid mine drainage: the link between melting permafrost and heavy metals in mountain lake.
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Spitzer, Philipp, Reichmann, Eva, and Tassoti, Sebastian
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HEAVY metals , *PERMAFROST , *ANALYSIS of heavy metals , *MELTING , *LAKES , *ACID mine drainage - Abstract
The article explores the connection between melting permafrost and heavy metals in mountain lakes. It explains that as permafrost melts and glaciers retreat, heavy metals can become more concentrated in streams and lakes, especially in areas with sulfide-containing bedrock. This is due to acid mine drainage, which lowers the pH of the water and causes heavy metals to dissolve. The article also presents a series of experiments that can be used in classrooms to demonstrate the effects of acid mine drainage on water quality. These experiments allow students to observe the pH changes and increased copper content in water samples exposed to pyrite. The experiments provide a hands-on learning experience for high school chemistry and environmental science classes. [Extracted from the article]
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- 2024
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9. Numerical simulation of long-distance debris flows (lahars) on glacier-clad volcanoes: the case of Cotopaxi, Ecuador.
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Vasconez, Francisco J., Phillips, Jeremy, Woodhouse, Mark J., Andrade, S. Daniel, Neglia, Francesco, and Borselli, Lorenzo
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DEBRIS avalanches ,DIGITAL elevation models ,HAZARD mitigation ,LAHARS ,TOPOGRAPHY - Abstract
Volcanic debris flows (lahars) are highly destructive volcanic phenomena and present significant challenges in numerical simulation. This manuscript tackles the three fundamental requirements for modelling gravitational flows: determining plausible source configurations; selecting suitable topographic data; and employing appropriate mathematical models to assess the current hazard posed by long-distance lahars at Cotopaxi volcano. After incorporating these elements, we successfully simulated the characteristics of a future 1877- type lahar under current conditions, accounting for glacier size and topography. For the source conditions, or "scenario", we identified 27 equidistant source locations along the lower edge of the current glacier's extent. Each source was assigned a hydrograph based on the weighted volume of water available on Cotopaxi's current glacier. Additionally, we introduced a methodology for quantifying channel width when high-resolution digital elevation models (DEMs) are available. This method enabled us to determine the minimum pixel size required for accurate representation of ravine shapes. While higher resolution DEMs demand robust computational resources and extended computational timeframes, we upscaled Cotopaxi's DEM from 3 m to 15 m to balance accuracy and efficiency, as a 15-m DEM capture over 90% of the topography and reduces computing time significantly. Optimizing DEM selection is crucial, especially when contemplating future ensemble approaches. After employing the dynamic-based model Kestrel, parameterised for large lahars, we obtained predictions closely aligned with field observations, historical flow conditions inferred for the 1877 lahar-event, and results from previous simulation studies. Notably, we observed higher depths and speeds in canyons compared to plains, consistent with historical reports and previous studies. Minor discrepancies in the inundation area, when compared with existing hazard maps, emphasize the importance of understanding flow dynamics and lahar trajectories for effective hazard assessment and mitigation strategies. Furthermore, our results contribute valuable information to current hazard maps and can aid in damage quantification and cost/benefit analyses, particularly when planning the construction of mitigation infrastructure. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Accelerating Glacier Area Loss Across the Andes Since the Little Ice Age.
- Author
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Carrivick, Jonathan L., Davies, Morwenna, Wilson, Ryan, Davies, Bethan J., Gribbin, Tom, King, Owen, Rabatel, Antoine, García, Juan‐Luis, and Ely, Jeremy C.
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LITTLE Ice Age , *GLACIERS , *ALPINE glaciers , *ENVIRONMENTAL engineering , *ENVIRONMENTAL protection , *AQUATIC ecology , *ENVIRONMENTAL management - Abstract
Andean glaciers are losing mass rapidly but a centennial‐scale context to those rates is lacking. Here we show the extent of >5,500 glaciers during the Little Ice Age chronozone (LIA; c. 1,400 to c. 1,850) and compute an overall area change of −25% from then to year 2000 at an average rate of −36.5 km2 yr−1 or −0.11% yr−1. Glaciers in the Tropical Andes (Peru, Bolivia) have depleted the most; median −56% of LIA area, and the fastest; median −0.16% yr−1. Up to 10 × acceleration in glacier area loss has occurred in Tropical mountain sub‐regions comparing LIA to 2,000 rates to post‐2000 rates. Regional climate controls inter‐regional variability, whereas local factors affect intra‐region glacier response time. Analyzing glacier area change by river basins and by protected areas leads us to suggest that conservation and environmental management strategies should be re‐visited as proglacial areas expand. Plain Language Summary: Andean glaciers are melting fast but how that rate compares in a longer‐term context is unknown. In this study we mapped the extent of >5,500 glaciers during the Little Ice Age, which was the last major glacial advance culminating about c. 150 years ago. We analyzed the change in glacier size and computed overall area change of −25% from the LIA to year 2000 at a rate of −36.5 km2 per year or −0.11% per year. Glaciers within Peru and Bolivia have shrunk the most by median −56% of LIA area, and the fastest by median −0.16% per year. We discuss that these glaciers are depleting and retreating due to climate change but that response is compounded by glacier size, shape and terminus environment effects. As glaciers melt they reveal proglacial landscapes that tend to be highly unstable, impacting water resources, natural hazards and terrestrial and aquatic ecology. Key Points: Little Ice Age (LIA) chronozone extent of >5,500 glaciers mapped from geomorphological evidenceOverall glacier area change of −25% to year 2000 at a rate of −36.5 km2 yr−1 or −0.11% yr−1Up to 10 × acceleration in glacier area loss for Tropical sub‐regions comparing LIA to 2,000 with post‐2000 rates [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Summer Hydrography Conditions at Proglacial Fjord Entrances Along East Greenland.
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Rysgaard, S., Mortensen, J., Haxen, M., Gillard, L. C., and Risgaard‐Petersen, N.
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HYDROGRAPHY ,FJORDS ,TERRITORIAL waters ,GREENLAND ice ,RUNOFF ,GLACIERS ,WATER masses ,COASTS ,ALPINE glaciers - Abstract
Climate change is causing widespread melting of land and sea ice in the Arctic, leading to an increase in freshwater input to the ocean. This may have an impact on ocean circulation, marine ecosystems, and biodiversity in the region. Our findings provide new insights into the summer hydrography conditions at proglacial fjord entrances along large parts of the east coast of Greenland. As most freshwater exits the Arctic Ocean through Fram Strait this study focuses on understanding the origin of spatial distribution of temperature and freshwater in the coastal waters in East Greenland. We find that Polar Water and the Atlantic Water variants (Eurasian Basin Atlantic Water/Subpolar Mode Water) dominate coastal waters north and south of Denmark Strait, respectively, and that coastal waters are influenced by advected meltwater from the Arctic Ocean, glacier meltwater and local precipitation. Combining hydrographic observations, water isotope data, and water source fraction analysis, we show that glacier meltwaters can be detected at fjord entrances and down to approximately 200 m. Integrated over the upper 200 m of the water column, glacial meltwater account for approximately 9%, precipitation for around 8% and Polar Water (including sea ice melt) for approximately 83% of the freshwater observed along the East Greenland coast. Below 200 m, Atlantic Water variants dominate the entire coastal section. The freshwater along East Greenland stays close to the coast and we could not detect any glacier meltwater at the slope. Plain Language Summary: The rapid warming of our planet has increased freshwater input to the Arctic Ocean. A major portion of this freshwater is exiting through Fram Strait. Also, meltwater runoff from tundra lands and glaciers connected to the Greenland ice sheet is an increasingly significant freshwater source to fjords. At present, incomplete observations exist regarding the spatial distribution of freshwater and its origin along East Greenland. Here we present results from a compressed survey of the pan‐East Greenland coastal system from the entrance of fjords. We describe the spatial distribution of water masses and source water fractions along East Greenland and their link to proglacial fjords. Key Points: Polar Water and Atlantic Water variants dominate East Greenland coastal waters north and south of Denmark Strait, respectivelyGlacier meltwater cannot be detected at the slope and most Polar Water, meteoric water, and glacier meltwater are confined to the coastAlong the coast, glacial meltwater account for ∼9%, precipitation for ∼8% and Polar Water (including sea ice melt) for ∼83% of the freshwater [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. Alaskan Glacial Dust Is an Important Iron Source to Surface Waters of the Gulf of Alaska.
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Crusius, John, Lao, Carsten A., Holmes, Thomas M., and Murray, James W.
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IRON , *TRACE metals , *RARE earth metals , *LAST Glacial Maximum , *DUST , *GEOLOGICAL time scales , *MELTWATER , *COPPER surfaces - Abstract
This work evaluates glacial dust as a source of sediment, and associated iron (Fe), to the Fe‐limited Gulf of Alaska (GoA). A reanalysis of GoA sediment data, using rare earth elements and thorium as provenance tracers, suggests a flux to the ocean surface of Copper River (AK) glacial dust, and associated Fe, that is comparable to the flux of dust from Asia, at least 1,000 km from the narrow mountain valley glacial dust source area. This work suggests dust from Asia may not be the largest source of Fe to the GoA. Dust models fail to accurately simulate this glacial dust transport because their coarse resolution underestimates wind speeds, and the dust flux. This work suggests that glacial dust fluxes may have been important in the geologic past (e.g., the last glacial maximum) from locations where there was more extensive coverage by glaciers than at present. Plain Language Summary: The growth of phytoplankton, the base of the marine food web, is known to be limited by availability of the micronutrient iron in the Gulf of Alaska. We evaluated the importance of glacial dust in this region as a source of iron, and other trace metals, by using concentrations of the rare earth elements and thorium in particles as tracers of their geographic origin. We analyzed for these elements in glacial dust samples from the Copper River valley (Alaska), the largest source of glacier‐derived dust. Together with previously published concentrations for dust from Asia and volcanic material, we estimated the inputs of each source material to the sediments of the Gulf of Alaska. This information, together with published sediment mass accumulation rates, suggests an important contribution of Alaskan glacial dust and associated iron, to surface waters of the Gulf of Alaska, at least 1,000 km from the source. Dust models fail to accurately simulate this dust transport because their coarse spatial resolution substantially underestimates wind speeds. Glacial dust fluxes may have been important sources of iron in the geologic past (e.g., the Last Glacial Maximum) from New Zealand and South America, when there was more extensive glacial coverage. Key Points: Copper River glacial dust contributes substantially to Gulf of Alaska sediments, and associated iron to surface watersDust models lack sufficient spatial resolution to accurately simulate the winds that drive the flux of glacial dust from narrow valleysGlacial dust‐associated iron may have been important in the geologic past in times and locations with more extensive glacial coverage [ABSTRACT FROM AUTHOR]
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- 2024
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13. Mapping Glacier Structure in Inaccessible Areas From Turning Seismic Sources Into a Dense Seismic Array.
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Nanni, Ugo, Roux, Philippe, and Gimbert, Florent
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SEISMIC arrays , *PHASE velocity , *GLACIERS , *SPATIAL resolution , *INTERFEROMETRY , *MICROSEISMS - Abstract
Understanding glaciers structural heterogeneity is crucial for assessing their fate. Yet, places where structure changes are strong, such as crevasses fields, are often inaccessible for direct instrumentation. To overcome this limitation, we introduce an innovative technique that transforms seismic sources, here generated by crevasses, into virtual receivers using source‐to‐receiver spatial reciprocity. We demonstrate that phase interference patterns between well‐localized seismic sources can be leveraged to retrieve phase velocity maps using Seismic Michelson Interferometry. The obtained phase velocity exhibits sensitivity to changes in glacier structure, offering insights into the origins of mechanical property changes, with spatial resolution surpassing traditional methods by a factor of five. In particular, we observe sharp variations in phase velocity related to strongly damaged subsurface areas indicating a complex 3‐D medium. Applying this method more systematically and in other contexts will enhance our understanding of the structure of glaciers and other seismogenic environments. Key Points: We transform seismic sources from crevasses into virtual receivers using source‐to‐receiver spatial reciprocityWe derive phase velocity maps in previously inaccessible areas with a resolution five times larger than traditional approachesWe retrieve the influence of glacier geometry and structural heterogeneity on the glacier mechanical properties [ABSTRACT FROM AUTHOR]
- Published
- 2024
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14. The Observed Near-Surface Energy Exchange Processes over Arctic Glacier in Summer.
- Author
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Zhou, Libo, Zhu, Jinhuan, Kong, Linlin, Li, Peng, Ma, Shupo, Li, Fei, Zou, Han, Zhang, Meigen, and Repina, Irina
- Abstract
Under Arctic warming, near-surface energy transfers have significantly changed, but few studies have focused on energy exchange over Arctic glacier due to limitations in available observations. In this study, the atmospheric energy exchange processes over the Arctic glacier surface were analyzed by using observational data obtained in summer 2019 in comparison with those over the Arctic tundra surface. The energy budget over the glacier greatly differed from that over the tundra, characterized by less net shortwave radiation and downward sensible heat flux, due to the high albedo and icy surface. Most of the incoming solar radiation was injected into the glacier in summer, leading to snow ice melting. During the observation period, strong daily variations in near-surface heat transfer occurred over the Arctic glacier, with the maximum downward and upward heat fluxes occurring on 2 and 6 July 2019, respectively. Further analyses suggested that the maximum downward heat flux is mainly caused by the strong local thermal contrast above the glacier surface, while the maximum upward heat transfer cannot be explained by the classical turbulent heat transfer theory, possibly caused by countergradient heat transfer. Our results indicated that the near-surface energy exchange processes over Arctic glacier may be strongly related to local forcings, but a more in-depth investigation will be needed in the future when more observational data become available. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Dynamic LIA advances hastened the demise of small valley glaciers in central Svalbard
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Erik S. Mannerfelt, Andrew J. Hodson, Lena Håkansson, and Harold Lovell
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Svalbard ,glacier ,little ice age ,geomorphology ,photogrammetry ,Environmental sciences ,GE1-350 ,Environmental engineering ,TA170-171 - Abstract
Most small land-terminating glaciers in Svalbard have experienced large recession since the Little Ice Age (LIA) and today are thin, cold, and largely inactive. This likely contrasts to their LIA conditions, but the observational record from that time is sparse. We investigate the evolution of five small glaciers in central Nordenskiöld Land, Svalbard, from the LIA to 2019. Photogrammetric reconstructions and ground penetrating radar are used to reconstruct their geometric changes since 1936, and historical observation, photographs, and geomorphological mapping extend this history to before the 1900s. Our results show that from 1936 to 2019, the study glaciers on average lost 49.6% of their area and 77.4% ± 7.7% of their volume, with the greatest volume loss at Scott Turnerbreen of 91% ± 5%. Four out of these five glaciers strongly indicate a history of surge-like advances near the end of the LIA within one or two decades, and the rate of subsequent mass loss seems connected to their previous dynamics. This apparent switch to high activity during a period of rapid climatic change, could have implications for our understanding of past and future glacier evolution; climate change and highly dynamic glacier responses may be more connected than previously thought.
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- 2024
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16. Geomorphology and Sedimentology of a Rapidly Retreating Alpine Glacier: Insights From the Taschachferner, Tirol, Austria
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D. P. Le Heron, P. Mejías Osorio, M. Heninger, and B. J. Davies
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glacier ,mountain ,Alps ,sedimentology ,climate change ,society ,Dynamic and structural geology ,QE500-639.5 - Abstract
The rapid retreat and fragmentation of Alpine glaciers is widely reported as humanity faces dramatic climate change in mountainous regions. This rapid change leads to changes in sedimentary processes, which are exposed in recently deglaciated regions. These Alpine glacier forefields offer a wide spectrum of settings through which the ancient sedimentary record can be interpreted. Glacial valley orientation, slope inclination and lithology, and plumbing of subglacial and englacial meltwater drainage all influence the immediate preservation potential of glacial sediments upon deposition. In this contribution, we explore the geomorphology and sedimentology of the Taschachferner (a valley glacier), presenting a new geological-geomorphological map. This small glacier drains an icefield in the Ötztal Alps, and its current ice margin lies at approximately 2550 m a.s.l. Thus far, the glacial sedimentology and its bedrock geology have not been subject to investigation. The bedrock geology is dominated by E-W striking units of paragneiss and amphibolite, and the latter exhibit a series of well-preserved striations together with meltwater-sculpted bedforms (p-forms). The lower region of the glacier can be divided into two parts: (i) a clean-ice part, on the northern valley side with a low, subdued profile and (ii) a debris-covered part at the southern valley side, covered with supraglacial debris. The valley margins are dominated by several generations of lateral moraines, the most prominent of which corresponds to the 1852 Little Ice Age Maximum. A well-developed “hanging sandur” is observed immediately in front of the ice margin. This consists of a series of sand and gravel bars cradled in the lee of an interpreted regional fault cross-cutting the bedrock. Sandur deposition is currently influenced and overprinted by dead ice, influencing the trajectory and location of river channels and gravel bars. This paper provides clear lessons regarding the distribution of ice-margin facies associations, which must be incorporated into models of glacier decay in the context of a rapidly warming climate.
- Published
- 2024
- Full Text
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17. Narwhal (Monodon monoceros) associations with Greenland summer meltwater release
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Kristin L. Laidre, Marie J. Zahn, Malene Simon, Michael Ladegaard, Kathleen M. Stafford, Elizabeth Phillips, Twila Moon, Harry L. Stern, and Benjamin Cohen
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glacier ,Greenland ,habitat modeling ,narwhal ,passive acoustics ,Ecology ,QH540-549.5 - Abstract
Abstract Climate change is rapidly transforming the coastal margins of Greenland. At the same time, there is increasing recognition that marine‐terminating glaciers provide unique and critical habitats to ice‐associated top predators. We investigated the connection between a top predator occupying glacial fjord systems in Northwest Greenland and the properties of Atlantic‐origin water and marine‐terminating glaciers through a multiyear interdisciplinary project. Using passive acoustic monitoring, we quantified the summer presence and autumn departure of narwhals (Monodon monoceros) at glacier fronts in Melville Bay and modeled what glacier fjord physical attributes are associated with narwhal occurrence. We found that narwhals are present at glacier fronts after Greenland Ice Sheet peak summer runoff and they remain there during the period when the water column is becoming colder and fresher. Narwhals occupied glacier fronts when ocean temperatures ranged from −0.6 to 0.8°C and salinities between 33.2 and 34.0 psu at around 200 m depth and they departed on their southbound migration between October and November. Narwhals' departure was approximately 4 weeks later in 2019 than in 2018, after an extreme 2019 summer heatwave event that also delayed sea ice formation by 2 months. Our study provides further support for the niche conservative narwhal's preference for cold ocean temperatures. These results may inform projections about how future changes will impact narwhal subpopulations, especially those occupying Greenland glacial fjords.
- Published
- 2024
- Full Text
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18. Quantifying the warming-induced impact of glacier storage change on runoff using Budyko framework: A case study in the Tarim River basin
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Yuanbo Chen, Hanbo Yang, Changming Li, and Ziwei Liu
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Runoff ,Budyko Framework ,Glacier ,Attribution analysis ,Climate Change ,The Tarim River Basin ,Physical geography ,GB3-5030 ,Geology ,QE1-996.5 - Abstract
Study region: The Tarim River Basin Study focus: Under the warming climate, understanding the impact of glacier storage changes on runoff is essential for maintaining ecosystems and freshwater supplies to lowland areas in cold regions. However, the lack of glacier data significantly hampers long-term analysis of this impact. To address this issue, we proposed a practical method within the Budyko framework to quantify the warming-induced changes in glacier storage. Based on this framework, we further developed a transparent elasticity approach to quantify how runoff responds to the glacier changes, with observations from 17 glacier-covered catchments in the Tarim River Basin, China. New hydrological insights for the region: Our results show that a 1℃ temperature rise in this region would lead to a 5–29 % increase in runoff attributable to warming-induced glacier storage change. On average, the glacier storage change contributes to approximately 25 % of runoff increases during 1960–2019. However, this positive trend may not be consistently sustained due to the non-linear and accelerated glacier loss in response to warming. The approach we present here provides efficient estimates for glacier-related hydrological changes in the Tarim River Basin and is transferable to other glacier-impacted regions due to its transparent methodology and low input requirements.
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- 2024
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19. Assessing GLOF Susceptibility and Risk Mapping Using Optical Remote Sensing Data: A Case Chapter of Upper Alakananda River Basin
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Rawat, Vikas, Singh, Shekhar, Negi, Mahabir Singh, Das, Jayanta, editor, and Halder, Somenath, editor
- Published
- 2024
- Full Text
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20. Microplastic in Glacier Region: Presence, Distribution, and Possible Sources
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Gosai, Hardik Giri, Yadav, Monika, Kumar, Ajay, editor, and Singh, Vijai, editor
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- 2024
- Full Text
- View/download PDF
21. Antarctic Ice Sheet Surface Mass Balance Using UAV-Based Digital Elevation Model
- Author
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Mahesh, B., Dhanush, S., Rakshita, C., Raghavendra, K. R., Geetha Priya, M., Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Aradhya, V. N. Manjunath, editor, Mahmud, Mufti, editor, Srinath, S., editor, Mahanand, B. S., editor, and Bharathi, R. K., editor
- Published
- 2024
- Full Text
- View/download PDF
22. A Narrative Review of Geospatial Techniques for assessing Climate Change Impacts on Cryosphere, Geo-environmental Hazards and Risks in the Himalayan Region
- Author
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Mir, Riyaz Ahmad, Ahmed, Rayees, Rather, Abid Farooq, Ahmad, Syed Towseef, Bhat, Irshad Ahmad, Wani, Gowhar Farooq, Javaid, Sumaira, Pandey, Prem C., editor, Kumar, Rajesh, editor, Pandey, Manish, editor, Giuliani, Gregory, editor, Sharma, R. K., editor, and Srivastava, Prashant K., editor
- Published
- 2024
- Full Text
- View/download PDF
23. Modelling Potential Zones of Gangotri Glacier Using GIS and ML in the Wake of Physico-Climatic Factors
- Author
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Khan, Zainab, Mohsin, Mohd, Ajmal, Uzma, Ahmad, Ateeque, Singh, Abha Lakshmi, editor, Jamal, Saleha, editor, and Ahmad, Wani Suhail, editor
- Published
- 2024
- Full Text
- View/download PDF
24. Estimation of Glacier Dynamics for Glacier De Corbassière Using Satellite Image Cross Correlation Approach
- Author
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Deva Jefflin, A. R., Geetha Priya, M., Sivaranjani, S., Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Tan, Kay Chen, Series Editor, Mahajan, Vasundhara, editor, Chowdhury, Anandita, editor, Singh, Sri Niwas, editor, and Shahidehpour, Mohammad, editor
- Published
- 2024
- Full Text
- View/download PDF
25. Risk and Uncertainty in Hydro-power Development in Uttarakhand Post Kedarnath and Chamoli Flood Disasters in Uttarakhand
- Author
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Mazumder, S. K., Sharma, Shivdayal, di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Timbadiya, P. V., editor, Patel, Prem Lal, editor, Singh, Vijay P., editor, and Manekar, Vivek L., editor
- Published
- 2024
- Full Text
- View/download PDF
26. Two-Stage Polsar Scattering Model-Based Classification Scheme for Improved Glacier Facies Mapping
- Author
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Panwar, Ruby, Kumar, Amit, and Kumar, Praveen
- Published
- 2024
- Full Text
- View/download PDF
27. Biogeochemical investigations of methane-rich groundwaters in high Arctic glacial catchments
- Author
-
Kleber, Gabrielle and Turchyn, Alexandra
- Subjects
Arctic ,biogeochemistry ,glacier ,methane - Abstract
Permafrost and glaciers in the high Arctic form a near-impermeable 'cryospheric cap' that traps a potentially large reservoir of sub-surface methane and prevents it from reaching the atmosphere. The vulnerability of the cryosphere to climate warming is making releases of this methane possible, but uncertainty in the magnitude and timing of such releases makes predictions of Arctic greenhouse gas emissions difficult. In Svalbard, where air temperatures are rising more than twice as fast as the average for the Arctic, glaciers are retreating and leaving behind exposed forefields that enable rapid methane escape. Through an extensive spatial study of proglacial groundwater springs on Svalbard, groundwater systems within glaciated catchments are found to be bringing to the surface deep-seated methane gas that was previously trapped beneath glaciers and permafrost in the Arctic. In this thesis, I estimate the amount of methane being released by such springs and discuss its origin. Through a temporal study conducted at a single glacial catchment, Vallåkrabreen, I use biogeochemical data collected from groundwaters during two melt seasons to investigate the sources of groundwaters and the origin of the methane they transport to the surface. Waters collected from 123 groundwater springs in the forefields of 78 land-terminating glaciers are supersaturated with methane up to 600,000-times greater than atmospheric equilibration. The spatial sampling revealed a geologic control on the extent of methane supersaturation, with strong evidence of a thermogenic source. I estimate annual methane emissions from proglacial groundwaters could be up to 2.31 kt across the Svalbard archipelago. Further investigations into marine-terminating glaciers indicate emergent methane emissions as these glaciers transition into fully land-based glaciers. My findings within the Vallåkrabreen catchment demonstrate an interconnected hydrological system where shallow and deep groundwaters mix to moderate methane emissions. During summer, deep methane-rich groundwaters sourced from upper catchment snowmelt are diluted by shallow oxygenated groundwaters, leading to some methane oxidation prior to its emergence at the surface. Microbial activity is an important methane sink along this flow-path, removing up to 62% of methane before it is brought to the surface. During winter, deep groundwaters remain active while many shallow systems shut off, reducing subsurface methane oxidation and permitting greater emissions. Ratios of the differing groundwater sources will change markedly in years to come as aquifer capacities and recharge volumes change in a warming climate. My findings reveal that climate-driven glacial retreat facilitates widespread release of methane, a positive feedback loop that has the potential to contribute to enhanced greenhouse gas emissions in the Arctic. The findings are highly relevant for other regions of the Arctic that, due to their geology, are likely to experience similar methane emissions, either currently or with further glacial retreat.
- Published
- 2023
- Full Text
- View/download PDF
28. Optimisation of water use in Kyrgyzstan agriculture: Analysis of modern and traditional irrigation methods to minimise losses and increase efficiency
- Author
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Ainura Batykova, Kasiet Musabayeva, Victoria Sultanbaeva, Oskon Osmonov, and Gulmira Shabikova
- Subjects
wastewater treatment plant ,drip irrigation ,sprinkler irrigation ,drought ,glacier ,lake issyk-kul ,Agriculture - Abstract
The study conducted on analysing the characteristics of wastewater composition before and after re-treatment is relevant in the context of environmental protection. The study aims to investigate the characteristics of wastewater before and after re-treatment using a pressure sorption filter. The results of the analysis of quantitative indicators of wastewater revealed that before treatment it was characterised by a wide range of indicators exceeding the normative levels. The greatest excess was observed in the content of suspended solids in sample No. 10, where their concentration reached 1,000 mg/l, which exceeded the normative values by 1.43 times. A pressure sorption filter was installed to improve the quality of treatment. The analysis showed that after its implementation, the wastewater indicators improved significantly: the content of suspended solids decreased by 6.67 times, which indicated the effectiveness of this treatment method. After treatment, the content of pollutants decreased to the levels corresponding to the norms. Economic calculation showed low costs for the installation and operation of the pressure sorption filter, which amounted to 22,570 KGS. It should be concluded that in the end, the results showed that the use of a drip irrigation system was cost-effective to implement because the investment amount of 2,765.2 thousand KGS paid off with additional profit in the period of 1.3 years. The results of the study can be used in practice by hydrologists, hydraulic engineers, resource scientists, environmental engineers, ecologists, ecologists-hydrobiologists, specialists in water management and environmental monitoring, as well as decision-makers in the field of ecology and environmental management to develop and implement measures for the implementation of environmental programmes and projects aimed at improving the environmental situation in the region
- Published
- 2024
- Full Text
- View/download PDF
29. Terrestrial glacial geomorphology of surge-type and non-surge-type glaciers on Svalbard
- Author
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Rebecca McCerery, Bethan Joan Davies, Harold Lovell, David Anthony Pearce, Rosalia Calvo-Ryan, Jakub Małecki, and John Woodward
- Subjects
Glacier ,geomorphology ,landsystems ,Arctic ,Svalbard ,Maps ,G3180-9980 - Abstract
This paper presents a map of terrestrial glacial geomorphology of eleven surge-type and non-surge-type glacier forefields in southwest and west Spitsbergen, Svalbard. Glacier forefields were mapped using a combination of field surveys and the use of an uncrewed airborne vehicle in September 2022 and satellite imagery captured in 2020, with mapping performed in ArcGIS Pro at a 1:5000 scale. Maps were constructed for glaciers in Van Kuelenfjorden and Van Mijenfjorden (southwest Spitsbergen), and in Isfjorden, Billefjorden a fjord branch of Isfjorden and St. Jonsfjorden (west Spitsbergen), to obtain a breadth of glacier types and features representative of glacial landsystems on Svalbard. The detailed landform inventory was divided into: (i) ice marginal, (ii) subglacial, (iii) glaciofluvial and glaciolacustrine, (iv) supraglacial and (v) other non-glacial and contemporary features. These detailed maps provide a geomorphological insight into the past and present characteristics of glaciers on Svalbard.
- Published
- 2024
- Full Text
- View/download PDF
30. Characteristics of runoff changes and their climatic factors in two different glacier-fed basins
- Author
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Sun Zhenqi, Wang Shijin, and Li Zhongqin
- Subjects
Runoff change ,Mann–Kendall test ,temperature ,precipitation ,glacier ,Environmental sciences ,GE1-350 ,Ecology ,QH540-549.5 - Abstract
The hydrological regulation function of glaciers in different watersheds is different. This study took the Yanggong River Basin (YRB) and Urumqi River Basin (URB) as two typical cases, to explore the runoff change differences and their responses to climate factors from 1979 to 2017. In the past 39 years, the YRB’s annual runoff showed an insignificant trend of increasing first and then decreasing, while the URB’s increasing trend was significant. From the 1980s to the 2010s, the YRB’s monthly runoff extremum occurred earlier than before, and the peak value decreased. The time of monthly runoff extremum in the URB has not changed, but the peak value is increasing. Both basins experienced an increase in annual temperatures from 1979 to 2017, with the rate of warming being more pronounced in the URB. The precipitation in the YRB had no significant trend from 1979 to 2017, and the significant increasing trend in annual precipitation extended in the URB from 1998 to 2010. The YRB’s runoff change was mainly influenced by the flood season precipitation, while the URB’s runoff increase was due to the temperature rise causing faster glacier and snow melt, and the summer precipitation change. In continental glacier basins with many glaciers, the regulation function of glaciers on total runoff is more significant.
- Published
- 2024
- Full Text
- View/download PDF
31. Bacterial diversity and biopotentials of Hamtah glacier cryoconites, Himalaya.
- Author
-
Singh, Purnima, Singh, Shiv Mohan, Takahiro Segawa, and Singh, Prashant Kumar
- Subjects
LIPASES ,BACTERIAL diversity ,INDUCTIVELY coupled plasma mass spectrometry ,GLACIERS ,GLOBAL warming ,ICE sheets ,PSEUDOMONAS - Abstract
Cryoconite is a granular structure present on the glaciers and ice sheets found in polar regions including the Himalayas. It is composed of organic and inorganic matter which absorb solar radiations and reduce ice surface albedo, therefore impacting the melting and retreat of glaciers. Though climate warming has a serious impact on Himalayan glaciers, the biodiversity of sub-glacier ecosystems is poorly understood. Moreover, cryoconite holes are unique habitats for psychrophile biodiversity hotspots in the NW Himalayas, but unfortunately, studies on the microbial diversity of such habitats remain elusive. Therefore, the current study was designed to explore the bacterial diversity of the Hamtah Glacier Himalaya using both culturable and non-culturable approaches. The culturable bacterial count ranged from 2.0 × 10³ to 8.8 × 10
5 colony-forming units (CFUs)/g at the different locations of the glacier. A total of 88 bacterial isolates were isolated using the culturable approach. Based on the 16S ribosomal RNA gene (16S rRNA), the identified species belong to seven genera, namely, Cryobacterium, Duganella, Janthinobacterium, Pseudomonas, Peribacillus, Psychrobacter, and Sphingomonas. In the non-culturable approach, high-throughput sequencing of 16S rRNA genes (using MiSeq) showed unique bacterial community profiles and represented 440 genera belonging to 20 phyla, namely, Proteobacteria, Actinobacteria, Firmicutes, Bacteroidetes, Chloroflexi, Acidobacteria, Planctomycetes, Cyanobacteria, Verrucomicrobia, Spirochaetes, Elusimicrobia, Armatimonadetes, Gemmatimonadetes, Deinococcus-Thermus, Nitrospirae, Chlamydiae, Chlorobi, Deferribacteres, Fusobacteria, Lentisphaerae, and others. High relative abundances of Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were observed in the samples. Phototrophic (Cyanobacteria and Chloroflexi) and nitrifier (Nitrospirae) in bacterial populations indicated sustenance of the micro-ecosystem in the oligotrophic glacier environment. The isolates varied in their phenotypic characteristics, enzyme activities, and antibiotic sensitivity. Furthermore, the fatty acid profiles of bacterial isolates indicate the predominance of branched fatty acids. Iso-, anteiso-, unsaturated and saturated fatty acids together constituted a major proportion of the total fatty acid composition. High cold-adapted enzyme activities such as lipase and cellulase expressed by Cryobacterium arcticum (KY783365) and protease and cellulase activities by Pseudomonas sp. strains (KY783373, KY783377-79, KY783382) provide evidence of the possible applications of these organisms. Additionally, antibiotic tests indicated that most isolates were sensitive to antibiotics. In conclusion, the present study contributed for the first time to bacterial diversity and biopotentials of cryoconites of Hamtah Glacier, Himalayas. Furthermore, the cold-adapted enzymes and polyunsaturated fatty acids (PUFAs)may provide an opportunity for biotechnology in the Himalayas. Inductively coupled plasma mass spectrometry (ICPMS) analyses showed the presence of several elements in cryoconites, providing a clue for the acceleratingmelting and retreating of theHamtah glacier. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
32. The Worth of Nature: Valuations of Glaciers in Alaskan and Norwegian Media Discourse.
- Author
-
Bruns, Catherine J. and Andersen, Ida Vikøren
- Subjects
VALUATION ,GLACIERS ,RHETORICAL analysis ,NORWEGIANS ,NEW business enterprises ,DISCOURSE - Abstract
This article presents a comparative case study of public valuation of glaciers in Alaska and Norway. The first case examines Alaska's Mendenhall Glacier, which has been central in public debate over the US Forest Service's proposed expansion of the Mendenhall Glacier Recreation Area. The second case centers on Norway's Svartisen glacier, which garnered international attention when the startup company, Svaice, announced its intent to extract glacier ice cubes for cocktail coolers at high-end bars and restaurants. A rhetorical analysis of newspaper coverage relevant to each case reveals that in both debates, instrumental, relational, and intrinsic values are attributed to the respective glaciers, and that government, business, and community actors hold the most power in these conversations. However, nuances within articulations of instrumental value suggest that Norwegian actors strive to balance human and glacier needs, whereas Alaskan actors largely prioritize human needs by constituting the glacier as a utilitarian object. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Optimisation of water use in Kyrgyzstan agriculture: Analysis of modern and traditional irrigation methods to minimise losses and increase efficiency.
- Author
-
Batykova, Ainura, Musabayeva, Kasiet, Sultanbaeva, Victoria, Osmonov, Oskon, and Shabikova, Gulmira
- Subjects
WATER use ,IRRIGATION ,ENVIRONMENTAL protection ,WASTEWATER treatment ,WATER quality - Abstract
The study conducted on analysing the characteristics of wastewater composition before and after re-treatment is relevant in the context of environmental protection. The study aims to investigate the characteristics of wastewater before and after re-treatment using a pressure sorption filter. The results of the analysis of quantitative indicators of wastewater revealed that before treatment it was characterised by a wide range of indicators exceeding the normative levels. The greatest excess was observed in the content of suspended solids in sample No. 10, where their concentration reached 1,000 mg/l, which exceeded the normative values by 1.43 times. A pressure sorption filter was installed to improve the quality of treatment. The analysis showed that after its implementation, the wastewater indicators improved significantly: the content of suspended solids decreased by 6.67 times, which indicated the effectiveness of this treatment method. After treatment, the content of pollutants decreased to the levels corresponding to the norms. Economic calculation showed low costs for the installation and operation of the pressure sorption filter, which amounted to 22,570 KGS. It should be concluded that in the end, the results showed that the use of a drip irrigation system was cost-effective to implement because the investment amount of 2,765.2 thousand KGS paid off with additional profit in the period of 1.3 years. The results of the study can be used in practice by hydrologists, hydraulic engineers, resource scientists, environmental engineers, ecologists, ecologists-hydrobiologists, specialists in water management and environmental monitoring, as well as decision-makers in the field of ecology and environmental management to develop and implement measures for the implementation of environmental programmes and projects aimed at improving the environmental situation in the region. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Back-analysis of the paraglacial slope failure at Grewingk Glacier and Lake, Alaska.
- Author
-
Lemaire, Emilie, Dufresne, Anja, Hamdi, Pooya, Higman, Bretwood, Wolken, Gabriel J., and Amann, Florian
- Subjects
- *
LANDSLIDES , *STRUCTURAL geology , *GLACIERS , *RELIEF models , *SEISMOGRAMS , *EARTHQUAKES - Abstract
The relationship between rock-slope failure and glacier retreat is complex, and paraglacial failures often lack clearly identified triggers. To better understand the role of glacier retreat in rock-slope failures, we analysed the processes that led to the October 1967 Grewingk landslide in Kachemak Bay State Park on the Kenai Peninsula, Southcentral Alaska. The rock material collapsed onto the glacier toe and into its pro-glacial lake and produced a tsunami wave that swept the outwash plain. On the day of the failure, rainfall and snowmelt were well within normal ranges, and seismic records show no significant shaking. Three years prior to the 1967 failure, the slope withstood the second largest earthquake ever recorded (Great Alaskan earthquake, MW 9.2). We reassessed the volume of the failure by differencing pre- and post-digital terrain models and found a value of 20–24 × 106 m3, which is four times smaller than a previous estimate. The back analysis of the Grewingk landslide is based on remote sensing data and field measurements including aerial satellite image analysis, detailed surveying and understanding of the structural geology, a kinematic analysis, and runout modelling. Our research provides an example of a major paraglacial failure that lacks an obvious trigger and points to several geological factors and changing environmental conditions that likely promote such failures. This study further indicates that the Grewingk landslide, pre-conditioned by the geometry of faults and joints, may have reached a critical stability state due to internal processes and the potential combined effects of seismic activity and glacier retreat prior to the collapse. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Monitoring a high mountain glacier through georeferenced time-lapse photography: Tapado, Dry Andes of Chile (30°S).
- Author
-
Vivero, Sebastián
- Subjects
- *
ALPINE glaciers , *GLACIERS , *CHRONOPHOTOGRAPHY , *AUTOMATIC meteorological stations , *URBAN agriculture , *DISPLACEMENT (Mechanics) , *IRRIGATION farming - Abstract
Glaciers and snow cover provide freshwater for irrigated agriculture and urban consumption in the Dry Andes. Given the aridity of this environment, sublimation losses are significant, making precise monitoring techniques crucial in estimating glacier changes. Continuous monitoring of glaciers is typically conducted through the use of automatic weather stations (AWS). However, these stations may not capture the full extent of glacier changes, warranting the use of additional monitoring techniques such as close-range remote sensing and satellite imagery. This study utilizes time-lapse photography acquired from 2013 to 2015 to examine the temporal and spatial albedo variations across the Tapado Glacier, along with the surface changes in the debris-covered section. Sequential orthorectified images were used to observe the spatial evolution of ice cliffs and supraglacial ponds as they changed over time. High-resolution displacement measurements were obtained using feature tracking methods on the debris-covered glacier. Additionally, distributed albedo maps were produced by comparing photographic data with point albedo measurements from an AWS. The results indicate decreased albedo values during summer, along with the expansion of supraglacial ponds and ice cliffs in the debris-covered region. The study also proposes a cost-effective remote site monitoring approach using time-lapse photography for continuous observation and data collection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Glacier area change (1993–2019) and its relationship to debris cover, proglacial lakes, and morphological parameters in the Chandra-Bhaga Basin, Western Himalaya, India.
- Author
-
Vatsal, Sarvagya, Azam, Mohd Farooq, Bhardwaj, Anshuman, Mandal, Arindan, Bahuguna, Ishmohan, Ramanathan, Alagappan, Raju, N. Janardhana, and Tomar, Sangita Singh
- Subjects
ALPINE glaciers ,LANDSAT satellites ,LAKES ,FIELD research ,GLACIERS ,CLIMATE change - Abstract
Glacier inventories serve as critical baseline data for understanding the impacts of climate change on glaciers. The present study maps the outlines of glaciers in the Chandra-Bhaga Basin (western Himalaya) for the years 1993, 2000, 2010, and 2019 using Landsat Thematic Mapper (TM), Enhanced Thematic Mapper (ETM), and Operational Land Imager (OLI) datasets. A total of 251 glaciers, each having an area above 0.5 km
2 , were identified, which include 216 clean-ice and 35 debris-covered glaciers. Area changes are estimated for three periods: 1993–2000, 2000–2010, and 2010–2019. The total glacierized area was 996 ± 62 km2 in 1993, which decreased to 973 ± 70 km2 in 2019. The mean rate of glacier area loss was higher in the recent decade (2010–2019), at 0.036 km2 , compared to previous decades (0.029 km2 in 2000–2010 and 0.025 km2 in 1993–2000). Supraglacial debris cover changes are also mapped over the period of 1993 and 2019. It is found that the supraglacial debris cover increased by 14.12 ± 2.54 km2 (15.2%) during 1993–2019. Extensive field surveys on Chhota Shigri, Panchi II, Patsio, Hamtah, Mulkila, and Yoche Lungpa glaciers were carried out to validate the glacier outlines and supraglacial debris cover estimated using satellite datasets. Controls of various morphological parameters on retreat were also analyzed. It is observed that small, clean ice, south oriented glaciers, and glaciers with proglacial lakes are losing area at faster rates than other glaciers in the basin. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
37. RETROCESO DEL GLACIAR DEL CARIHUAIRAZO Y SUS IMPLICACIONES EN LA COMUNIDAD DE CUNUCYACU.
- Author
-
Hidalgo, David, Domínguez, Christian, Villacís, Marcos, Ruíz, Jean-Carlos, Maisincho, Luis, Cáceres, Bolívar, Crespo-Pérez, Verónica, Condom, Thomas, and Piedra, David
- Subjects
- *
AERIAL photographs , *METEOROLOGICAL stations , *VOLCANIC eruptions , *CLIMATE change , *MOUNTAINEERING , *ALPINE glaciers , *GLACIERS - Abstract
The retreat of glaciers is a reality throughout the Andes Mountain range, especially in low-altitude mountains. One of these cases is the loss of the remaining ice mass in Carihuairazo (Tungurahua, Ecuador), which in recent years has experienced a considerable retreat. This research aims to characterize the retreat of this glacier and its implications for the nearby community (Cunucyacu) through the application of a multi-source methodology, which includes the collection of glacier aerial photographs, data from nearby meteorological stations, the use of global climate reanalysis data, interviews with community members, and mountaineers who work and frequent the area. To characterize the glacier's mass evolution, a hydroglaciological model was applied, using input data from meteorological series, and its parameters were calibrated with the photographic record of the glacier's outline. The results show a glacier loss of 99% of its surface in 1956 (0.34 km2) by 2021. The model successfully simulates the glacier area variation over 67 years, revealing a continuous decrease since 1978, with short periods of recovery and equilibrium, where temperature is the variable that best explains the glacier's retreat. However, the model fails to consider the effect of external factors, such as the eruption of the Tungurahua volcano that could enhance the glacier retreat. The Carihuairazo glacier is in a situation of inevitable disappearance, highlighting the vulnerabilities of communities facing this phenomenon as a consequence of climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. A call for an accurate presentation of glaciers as water resources.
- Author
-
Gascoin, Simon
- Subjects
- *
WATER supply , *SCIENTIFIC literature , *GLACIAL melting , *IRRIGATION , *SURFACE contamination , *GLACIERS - Abstract
Glaciers are often portrayed as an important water resource in scientific research and public debate. However, the scientific literature calls for caution when presenting this idea. While melting glaciers can increase water insecurity, their contribution to runoff is often minor and other factors like excessive groundwater pumping for irrigation or surface and groundwater contamination pose much greater threats to water availability. As we consider the wide range of environmental impacts due to glacier changes, we must also question the “glacier as water resource” narrative that may unnecessarily contribute to public anxiety. This article is categorized under: Human Water > Water as Imagined and Represented Science of Water > Water and Environmental Change [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. The Okjökull Memorial and Geohuman Relations.
- Author
-
HOWE, CYMENE and BOYER, DOMINIC
- Subjects
GLACIERS ,CLIMATE change ,CLIMATOLOGY ,ANTHROPOLOGY ,HUMAN beings - Abstract
Copyright of Social Anthropology / Anthropologie Sociale is the property of Berghahn Books and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
40. Numerical simulation of long-distance debris flows (lahars) on glacier-clad volcanoes: the case of Cotopaxi, Ecuador
- Author
-
Francisco J. Vasconez, Jeremy Phillips, Mark J. Woodhouse, and S. Daniel Andrade
- Subjects
debris flow ,lahar ,DEM ,numerical simulation ,glacier ,Cotopaxi volcano ,Science - Abstract
Volcanic debris flows (lahars) are highly destructive volcanic phenomena and present significant challenges in numerical simulation. This manuscript tackles the three fundamental requirements for modelling gravitational flows: determining plausible source configurations; selecting suitable topographic data; and employing appropriate mathematical models to assess the current hazard posed by long-distance lahars at Cotopaxi volcano. After incorporating these elements, we successfully simulated the characteristics of a future 1877-type lahar under current conditions, accounting for glacier size and topography. For the source conditions, or “scenario”, we identified 27 equidistant source locations along the lower edge of the current glacier’s extent. Each source was assigned a hydrograph based on the weighted volume of water available on Cotopaxi’s current glacier. Additionally, we introduced a methodology for quantifying channel width when high-resolution digital elevation models (DEMs) are available. This method enabled us to determine the minimum pixel size required for accurate representation of ravine shapes. While higher resolution DEMs demand robust computational resources and extended computational timeframes, we upscaled Cotopaxi’s DEM from 3 m to 15 m to balance accuracy and efficiency, as a 15-m DEM capture over 90% of the topography and reduces computing time significantly. Optimizing DEM selection is crucial, especially when contemplating future ensemble approaches. After employing the dynamic-based model Kestrel, parameterised for large lahars, we obtained predictions closely aligned with field observations, historical flow conditions inferred for the 1877 lahar-event, and results from previous simulation studies. Notably, we observed higher depths and speeds in canyons compared to plains, consistent with historical reports and previous studies. Minor discrepancies in the inundation area, when compared with existing hazard maps, emphasize the importance of understanding flow dynamics and lahar trajectories for effective hazard assessment and mitigation strategies. Furthermore, our results contribute valuable information to current hazard maps and can aid in damage quantification and cost/benefit analyses, particularly when planning the construction of mitigation infrastructure.
- Published
- 2024
- Full Text
- View/download PDF
41. Accelerating Glacier Area Loss Across the Andes Since the Little Ice Age
- Author
-
Jonathan L. Carrivick, Morwenna Davies, Ryan Wilson, Bethan J. Davies, Tom Gribbin, Owen King, Antoine Rabatel, Juan‐Luis García, and Jeremy C. Ely
- Subjects
glacier ,ice cap ,little ice age ,andes ,icefield ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Andean glaciers are losing mass rapidly but a centennial‐scale context to those rates is lacking. Here we show the extent of >5,500 glaciers during the Little Ice Age chronozone (LIA; c. 1,400 to c. 1,850) and compute an overall area change of −25% from then to year 2000 at an average rate of −36.5 km2 yr−1 or −0.11% yr−1. Glaciers in the Tropical Andes (Peru, Bolivia) have depleted the most; median −56% of LIA area, and the fastest; median −0.16% yr−1. Up to 10 × acceleration in glacier area loss has occurred in Tropical mountain sub‐regions comparing LIA to 2,000 rates to post‐2000 rates. Regional climate controls inter‐regional variability, whereas local factors affect intra‐region glacier response time. Analyzing glacier area change by river basins and by protected areas leads us to suggest that conservation and environmental management strategies should be re‐visited as proglacial areas expand.
- Published
- 2024
- Full Text
- View/download PDF
42. Alaskan Glacial Dust Is an Important Iron Source to Surface Waters of the Gulf of Alaska
- Author
-
John Crusius, Carsten A. Lao, Thomas M. Holmes, and James W. Murray
- Subjects
dust ,Alaska ,glacier ,glacial particle ,Copper River ,iron ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract This work evaluates glacial dust as a source of sediment, and associated iron (Fe), to the Fe‐limited Gulf of Alaska (GoA). A reanalysis of GoA sediment data, using rare earth elements and thorium as provenance tracers, suggests a flux to the ocean surface of Copper River (AK) glacial dust, and associated Fe, that is comparable to the flux of dust from Asia, at least 1,000 km from the narrow mountain valley glacial dust source area. This work suggests dust from Asia may not be the largest source of Fe to the GoA. Dust models fail to accurately simulate this glacial dust transport because their coarse resolution underestimates wind speeds, and the dust flux. This work suggests that glacial dust fluxes may have been important in the geologic past (e.g., the last glacial maximum) from locations where there was more extensive coverage by glaciers than at present.
- Published
- 2024
- Full Text
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43. Mapping Glacier Structure in Inaccessible Areas From Turning Seismic Sources Into a Dense Seismic Array
- Author
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Ugo Nanni, Philippe Roux, and Florent Gimbert
- Subjects
glacier ,seismic interferometry ,crevasses ,dense seismic array ,imagery ,seismic noise ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract Understanding glaciers structural heterogeneity is crucial for assessing their fate. Yet, places where structure changes are strong, such as crevasses fields, are often inaccessible for direct instrumentation. To overcome this limitation, we introduce an innovative technique that transforms seismic sources, here generated by crevasses, into virtual receivers using source‐to‐receiver spatial reciprocity. We demonstrate that phase interference patterns between well‐localized seismic sources can be leveraged to retrieve phase velocity maps using Seismic Michelson Interferometry. The obtained phase velocity exhibits sensitivity to changes in glacier structure, offering insights into the origins of mechanical property changes, with spatial resolution surpassing traditional methods by a factor of five. In particular, we observe sharp variations in phase velocity related to strongly damaged subsurface areas indicating a complex 3‐D medium. Applying this method more systematically and in other contexts will enhance our understanding of the structure of glaciers and other seismogenic environments.
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- 2024
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44. Streamflow abrupt change and the driving factors in glacierized basins of Tarim Basin, Northwest China
- Author
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Cheng-De Yang, Min Xu, Shi-Chang Kang, Cong-Sheng Fu, Wei Zhang, and Di-Di Hu
- Subjects
Abrupt change ,Streamflow ,Hybrid model ,Tarim Basin ,Glacier ,Meteorology. Climatology ,QC851-999 ,Social sciences (General) ,H1-99 - Abstract
A climate transition towards warm–wet conditions in Northwest China has drawn much attention. With continuous climate change and universal glacier degradation, increasing water-related hazards and vulnerability have become one of the important problems facing the Tarim Basin. However, the impacts of the climate transition on streamflow abrupt change and extreme hydrological events were less discussed, especially in glacial basins. In the present study, the discharge datasets in four glacial basins of Tarim Basin from 1979 to 2018 were constructed using the GRU-GSWAT+ model first. The differences in streamflow characteristics, the shift of hydrological extreme pattern, and potential changes of the controlling factors before and after the abrupt changes were investigated. The results indicated that the abrupt change point (ACP) in streamflow occurred in 2000 in the Qarqan River Basin, 2002 in the Weigan River Basin, and 1994 in the Aksu River Basin and the Yarkant River Basin. A general decrease in streamflow before the ACP has shifted to a notable upward trend in the Qarqan River Basin and the Aksu River Basin, while minor upward fluctuations were observed in other basins. Moreover, the hydrological characteristics in extreme events vary dramatically before and after the ACPs, characterized by a pronouncing shift from drought-dominant pattern to wet events dominated pattern. The driven climate factors have been altered after the ACPs with notable spatial heterogeneity, in which temperature remained as the dominant role in meltwater-dominated basins while the influence of precipitation has increased after the ACPs, whereas the sensitivity of temperature on streamflow change has been enhanced in basins dominated by precipitation such as the Qarqan River Basin. Owing to the evident warming–wetting trend and glacier compensation effect, both the inter-annual and intra-annual streamflow fluctuations can be efficiently smoothed in basins with a high glacier area ratio (GAR). These findings provide a further understanding of the abrupt change in streamflow under the exacerbated climate and glacier change in mountainous arid regions.
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- 2024
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45. The Last Glaciation and Ice-Dammed Lakes in the South-East Altai
- Author
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I. D. Zolnikov, I. C. Novikov, E. V. Deev, A. V. Panin, and R. N. Kurbanov
- Subjects
late pleistocene ,glacier ,glacier-dammed lake ,geomorphological mapping ,gorny altai ,mis 2 ,Science - Abstract
The palaeogeographic scheme of the distribution of glaciers and ice-dammed lakes in the Altai during the last global glaciation (MIS-2) was compiled based on a detailed large-scale geomorphological survey. Analysis of geomorphological traces of glaciers of this time indicates that they occupied smaller areas than those of the first Late Pleistocene glaciation. By this means, the ice dams created by them were smaller that resulted in small sizes of ice-dammed lakes. The preserved levels of terraces indicate that during the first Late Pleistocene glaciation in the Kurai-Chuya depression system the ancient lake was the only one with a level of 2250 m and a total volume of 1.70 km3. During the second Late Pleistocene glaciation in the south-east Gorny Altai, another separate lake existed which was the Bartal-Kurai Lake with a level of 1700 m and a volume of 45 km3. This lake was dammed by the Mashey Glacier, which descended from the northern slopes of the North Chuaya Range. In the Chuya Depression, the existence of a landslide-dammed lake with a volume of 0.7 km3 and a level 1.750 m has been found. Its formation was not associated with glaciers of the MIS-2 stage. Direct dating of the last ice-dammed lake in the Chuya Depression with a level of 1950 m and a volume of 140 km3 has not yet been determined. This lake was dammed by the Kuehtanar Glacier, which descended from the southern slope of the Kurai ridge. The volume of ice-dammed waters of the MIS-2 time was an order of magnitude smaller than it was in the first Late Quaternary glaciation. This explains the much lower intensity of erosive and accumulative processes associated with the mega-flood occurred due to the breakthrough of the lakes during MIS-2.
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- 2024
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46. Multisensor Glacier Surface Classification Using Confidence-Aware Explainable Inverse-Mapping Neural Network
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Gunjan Joshi, Celia A. Baumhoer, Andreas J. Dietz, Ryo Natsuaki, and Akira Hirose
- Subjects
Explainable neural network ,glacier ,great aletsch glacier ,inverse mapping ,optical satellite ,sahara dust events (SDEs) ,Ocean engineering ,TC1501-1800 ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Mapping snow cover at the end of the ablation season allows us to extract the snow line altitude (SLA). The SLA is an important proxy for the equilibrium line altitude of a glacier and an indicator of glacier health. With the increase in both active and passive remote sensing satellites, the accuracy and effectiveness of glacier monitoring can be enhanced, as the two sensors offer complementary information. In this article, we focus on the combination of Sentinel-1 synthetic aperture radar (SAR) and Sentinel-2 optical data to perform glacial classification using an explainable neural network and thereafter determine SLA. In addition, confidence-aware inverse mapping dynamics is used to understand the result reliability and the individual sensor contributions. The proposed method is applied to the Great Aletsch Glacier in the European Alps, where an overall accuracy of 83% is observed compared to the ground truth data. We observe the glacier from 2015 to 2023, noting a retreat of the SLA to higher elevations by 36 to 133 m depending on the region. Apart from climate-related mass loss, the European Alps are also affected by dust deposited during Sahara dust events and contamination from algae. Thus, in this work, we assess the annual presence of contaminated snow on the glacier. The inverse mapping dynamics reveals the contributions of both SAR and optical sensor data in the classification. This multisensor approach is shown to mitigate the limitations of single-source data, providing a comprehensive understanding of glacier dynamics in the context of climate change.
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- 2024
- Full Text
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47. Spatio-Temporal Assessment of Areal Fragmentation and Volume of Snow Cover in the Central Himalaya
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Banerjee, Surajit, Sati, Vishwambhar Prasad, Almazroui, Mansour, and Chakraborty, Sudip
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- 2024
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48. Shallow and deep groundwater moderate methane dynamics in a high Arctic glacial catchment.
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Kleber, Gabrielle E., Magerl, Leonard, Turchyn, Alexandra V., Redeker, Kelly, Thiele, Stefan, Liira, Martin, Herodes, Koit, Øvreås, Lise, Hodson, Andrew, Kavan, Jan, and Chunlin Song
- Subjects
ALPINE glaciers ,GLACIERS ,GROUNDWATER ,AQUIFERS ,METHANE ,EARTH sciences ,METHANE hydrates ,ENVIRONMENTAL sciences - Abstract
Glacial groundwater can mobilize deep-seated methane from beneath glaciers and permafrost in the Arctic, leading to atmospheric emissions of this greenhouse gas. We present a temporal, hydro-chemical dataset of methane- rich groundwater collected during two melt seasons from a high Arctic glacial forefield to explore the seasonal dynamics of methane emissions. We use methane and ion concentrations and the isotopic composition of water and methane to investigate the sources of groundwater and the origin of the methane that the groundwater transports to the surface. Our results suggest two sources of groundwater, one shallow and one deep, which mix, and moderate methane dynamics. During summer, deep methane-rich groundwater is diluted by shallow oxygenated groundwater, leading to some microbial methane oxidation prior to its emergence at the surface. Characterization of the microbial compositions in the groundwater shows that microbial activity is an important seasonal methane sink along this flow-path. In the groundwater pool studied, we found that potential methane emissions were reduced by an average of 29% (±14%) throughout the summer due to microbial oxidation. During winter, deep groundwater remains active while many shallow systems shut down due to freezing, reducing subsurface methane oxidation, and potentially permitting larger methane emissions. Our results suggest that ratios of the different groundwater sources will change in the future as aquifer capacities and recharge volumes increase in a warming climate. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Predictive mapping of glacial sediment properties (Bellingshausen Dome, King George Island, Antarctica).
- Author
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Suleymanov, Azamat, Nizamutdinov, Timur, Mavlyudov, Bulat, and Abakumov, Evgeny
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STANDARD deviations ,ICE caps ,REGRESSION analysis ,DIGITAL elevation models ,LANDSLIDE hazard analysis - Abstract
Research in Antarctica is of great importance for understanding the Earth's climate system and the processes that drive it. This study evaluated the spatial distribution of glacial sediment properties on the Bellingshausen Dome or Collins Ice Cap (King George Island, Antarctica). The particle-size distribution, pH H
2 O, total organic carbon (TOC), mobile forms of ammonium nitrogen (N–NH4 ), potassium (K2 O), and phosphorus (P2 O5 ) were measured and then spatially modelled using regression kriging (RK) and ordinary kriging (OK) approaches. The terrain attributes (elevation, aspect, slope) derived from a digital elevation model with 10-m spatial resolution and distance from a coast were used as explanatory variables. Multiple linear regression models were fitted to describe the relationships between the covariates and properties. The performance of the models was evaluated by the mean absolute error (MAE), root mean square error (RMSE), coefficient of determination (R2 ), and Nash–Sutcliffe efficiency coefficient (NSE) indices. Overall, model performance statistics showed that RK models performed better than OK and the spatial patterns of some properties were closely related to the character of the glacier topography. Thus, the application of the RK method in combination with auxiliary environmental covariates improved the accuracy of spatial prediction. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
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50. Local Controls on Near‐Surface Glacier Cooling Under Warm Atmospheric Conditions.
- Author
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Shaw, Thomas E., Buri, Pascal, McCarthy, Michael, Miles, Evan S., and Pellicciotti, Francesca
- Subjects
ALPINE glaciers ,WEATHER ,GLACIERS ,KATABATIC winds ,CLIMATE extremes ,BOUNDARY layer (Aerodynamics) - Abstract
The near‐surface boundary layer can mediate the response of mountain glaciers to external climate, cooling the overlying air and promoting a density‐driven glacier wind. The fundamental processes are conceptually well understood, though the magnitudes of cooling and presence of glacier winds are poorly quantified in space and time, increasing the forcing uncertainty for melt models. We utilize a new data set of on‐glacier meteorological measurements on three neighboring glaciers in the Swiss Alps to explore their distinct response to regional climate under the extreme 2022 summer. We find that synoptic wind origins and local terrain modifications, not only glacier size, play an important role in the ability of a glacier to cool the near‐surface air. Warm air intrusions from valley or synoptically‐driven winds onto the glacier can occur between ∼19% and 64% of the time and contribute between 3% and 81% of the total sensible heat flux to the surface during warm afternoon hours, depending on the fetch of the glacier flowline and its susceptibility to boundary layer erosion. In the context of extreme summer warmth, indicative of future conditions, the boundary layer cooling (up to 6.5°C cooler than its surroundings) and resultant katabatic wind flow are highly heterogeneous between the study glaciers, highlighting the complex and likely non‐linear response of glaciers to an uncertain future. Plain Language Summary: The presence of a 0°C ice surface cools the near‐surface air and generates a unique micro‐climate that complicates a glaciers response to future warming. Using a new data series on three glaciers during an extreme summer of 2022, we explore how variable this cooling is in space and time and investigate the factors that can control it. We focus largely on the role of valley and synoptic winds that are found to affect glaciers of varying size and orientation differently, influencing the amount of heat transfer to the ice surface that glaciers receive from outside its own micro‐climate. Moreover, we find that the presence of glacier winds can act to enhance or reduce overall heat transfer to the glacier, depending on the wind strength and degree of boundary layer disruption. We highlight the complexities that are ignored in simpler melt modeling frameworks and demonstrate how, especially under extreme summer heat, indicative of future conditions, static parameters to relate glacier melt to temperature are likely to be inappropriate. Key Points: Glacier size and alignment with valley/synoptic wind gradients control the magnitude of near‐surface coolingValley/synoptic winds can occur between 19% and 64% of the time and contribute between 3% and 81% of total sensible heat to the ice surfaceLocalized cooling and turbulence in the boundary layer increase the complexity and non‐linearity of glacier response to climate [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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