Showing papers in "Arctic, Antarctic, and Alpine Research in 2019"
TL;DR: In high alpine environments, glacial shrinkage and permafrost warming due to climate change have significant consequences on mountaineering routes as mentioned in this paper, and few research projects have studied the relationsh...
Abstract: In high alpine environments, glacial shrinkage and permafrost warming due to climate change have significant consequences on mountaineering routes. Few research projects have studied the relationsh...
60 citations
TL;DR: In this paper, the authors predict that high-elevation ecosystems will experience increasing periods of above-average warmth and altered precipitation changes because of climate change, which causes uncertainties for community properties.
Abstract: High-elevation ecosystems will experience increasing periods of above-average warmth and altered precipitation changes because of climate change. This causes uncertainties for community properties ...
31 citations
TL;DR: In this paper, the 30 m resolution of a lake was used to study the effect of rapid changes in surface area by thermokarst expansion and by sudden lake drainage on arctic lakes and ponds.
Abstract: Lakes and ponds are important ecosystem components in arctic lowlands, and they are prone to rapid changes in surface area by thermokarst expansion and by sudden lake drainage. The 30 m resolution ...
28 citations
University of Alaska Fairbanks1, Bureau of Land Management2, Potsdam Institute for Climate Impact Research3, Alaska Department of Natural Resources4, United States Fish and Wildlife Service5, Lamont–Doherty Earth Observatory6, Alfred Wegener Institute for Polar and Marine Research7, Montana State University8, University of Alaska Anchorage9
TL;DR: In this article, the dynamics of habitat availability and connectivity are linked to how food webs support fish and waterbirds across diverse freshwater habitats, and a progressive refinement in understanding responses to change provides an example of adaptive management focused on ensuring responsible resource development in the Arctic.
Abstract: Vast mosaics of lakes, wetlands, and rivers on the Arctic Coastal Plain give the impression of water surplus. Yet long winters lock freshwater resources in ice, limiting freshwater habitats and water supply for human uses. Increasingly the petroleum industry relies on lakes to build temporary ice roads for winter oil exploration. Permitting water withdrawal for ice roads in Arctic Alaska is dependent on lake depth, ice thickness, and the fish species present. Recent winter warming suggests that more winter water will be available for ice- road construction, yet high interannual variability in ice thickness and summer precipitation complicates habitat impact assessments. To address these concerns, multidisciplinary researchers are working to understand how Arctic freshwater habitats are responding to changes in both climate and water use in northern Alaska. The dynamics of habitat availability and connectivity are being linked to how food webs support fish and waterbirds across diverse freshwater habitats. Moving toward watershed-scale habitat classification coupled with scenario analysis of climate extremes and water withdrawal is increasingly relevant to future resource management decisions in this region. Such progressive refinement in understanding responses to change provides an example of adaptive management focused on ensuring responsible resource development in the Arctic.
25 citations
TL;DR: In this article, the authors applied the modified Frost Number model to simulate frozen ground distributions in the Tibetan Plateau and calculated the maximum thawing depth by the Stefan approach, and classified the simulated frozen ground into three subzones: seasonal frozen ground zone, changing zone, and permafrost zone.
Abstract: Understanding the driving forces for alpine vegetation variations at different permafrost degrading stages is important when the Tibetan Plateau is experiencing climate warming. We applied the modified Frost Number model to simulate frozen ground distributions in the Tibetan Plateau and calculated the maximum thawing depth by the Stefan approach. We classified the simulated frozen ground into three subzones: seasonal frozen ground zone, changing zone, and permafrost zone. We evaluated the effects of precipitation, air temperature, and maximum thawing depth on Normalized Difference Vegetation Index (NDVI) in the subzones across five different stages from 1982 to 2012. The results show that permafrost zone, changing zone, and seasonal frozen ground zone account for about 30.6 percent, 23.3 percent, and 46.1 percent of the study area, respectively. Over the five stages, permafrost areas decreased at fast, slow, fastest, and then slowest rate from stage1 to stage 5, and the large continuous permafrost area has been degraded into pieces. Precipitation is strongly correlated with NDVI and contributes most `to the changes of NDVI. Maximum thawing depth and particularly air temperature show a much smaller correlation and contribute less to the variation rate of NDVI. The findings will have broad applications in investigating the impact of climate and environment changes on alpine vegetation variations in the Tibetan Plateau.
19 citations
TL;DR: In this paper, the authors examine changes in greenness over time in the Tibetan Plateau and examine the role of the Tibetan plateau in environmental change in light of global warming and changes in land management.
Abstract: Understanding the Tibetan Plateau’s role in environmental change has gained increasing scientific attention in light of warming and changes in land management. We examine changes in greenness over ...
18 citations
TL;DR: In this article, the first comprehensive inventory and analysis of rock glaciers in the hydrographic Great Basin (GB), United States, documenting 842 features (mean 9.9 m and range 0.1-201 m) across thirty-two mountain ranges.
Abstract: We present the first comprehensive inventory and analysis of rock glaciers in the hydrographic Great Basin (GB), United States, documenting 842 features (mean 9.9 ha; range 0.1–201 ha) across thirty-two mountain ranges. These encompassed 8° latitude (from 36.5°N to 44.3°N) and 11° longitude (from −110.7°W to −121.4°W), and composed 83.1 km2, or 1.1 percent, of the cumulative area above the lowest rock glacier elevation. Forty-five percent of the features were mapped as intact (containing ice) and occurred across sixteen mountain ranges. Rock glaciers conservatively contained cumulative water volume of 0.8924 km3. We also mapped 237 persistent ice fields from thirteen GB ranges. Ice-field water equivalent was 0.0653 km3; rock glaciers contributed 93 percent of the total water volume (rock glacier:icefield ratio, 14:1). Rock glaciers occurred on northerly aspects at high elevations (mean, 3,196 m) and had a mean annual air temperature of 1.7°C (range, 1.3–3.3°C). Contributions of water from rock-glacier springs and groundwater have not been included in GB hydrologic assessments, nor have rock glaciers been evaluated for their roles in supporting cold-adapted aquatic fauna and promoting vegetation communities and habitat for alpine terrestrial species. Rock glaciers provide hydrologic and ecologic refugia previously unrecognized in the GB with respect to warming future climates.
18 citations
TL;DR: In this paper, the authors assess the total storage, landscape distribution, and vertical partitioning of soil organic carbon stocks on the Brogger Peninsula, Svalbard, in order to assess the storage and distribution of CO stocks.
Abstract: In this study we assess the total storage, landscape distribution, and vertical partitioning of soil organic carbon (SOC) stocks on the Brogger Peninsula, Svalbard. This type of high Arctic...
17 citations
TL;DR: In this article, the first description of snow penitentes was given using molecular and microscopic approaches, using a model based on the Nieves Penitentes, a pinnacle-shaped ice structure found at high elevations in the dry Andes.
Abstract: Nieves penitentes are pinnacle-shaped ice structures found at high elevations in the dry Andes. Here we report, using molecular and microscopic approaches, the first description of snow alg...
16 citations
TL;DR: A changing Arctic climate may alter freshwater ecosystems as a result of warmer surface waters, longer open-water periods, reduced wintertime lake ice growth, and altered hydrologic connectiv...
Abstract: Changing Arctic climate may alter freshwater ecosystems as a result of warmer surface waters, longer open-water periods, reduced wintertime lake ice growth, and altered hydrologic connectiv...
16 citations
TL;DR: In this article, an important component of biodiversity in northern ecosystems and are involved in diverse ecological processes, they contribute to nutrient availability through nitrogen fixatio- ing through nitrogen fixation and nitrogen fixation.
Abstract: Lichens are an important component of biodiversity in northern ecosystems and are involved in diverse ecological processes. They contribute to nutrient availability through nitrogen fixatio...
TL;DR: In this article, the increasing dominance of deciduous shrubs in arctic-alpine ecosystems involves major shifts in plant functional group composition due to climate change, and the importance of these shrubs is examined.
Abstract: Ongoing responses to climate change in arctic-alpine ecosystems, including the increasing dominance of deciduous shrubs, involve major shifts in plant functional group composition. Because rates of...
TL;DR: It is suggested that shrub expansion may influence summer C cycling differently depending on plant community, as belowground respiration might increase in the heath and decrease in the meadow communities.
Abstract: Recent vegetation changes in arctic-alpine tundra ecosystems may affect several ecosystem processes that regulate microbe and soil functions. Such changes can alter ecosystem carbon (C) cycling with positive feedback to the atmosphere if plant C uptake is less than the amount of soil C released. Here, we examine how differences in plant functional traits, microbial activity, and soil processes within and across Salix-dominated shrub, dwarf shrub–dominated heath, and herb- and cryptogam-dominated meadow communities influence C cycling. We develop a hypothesized framework based on a priori model selection of variation in daytime growing season gross ecosystem photosynthesis (GEP) and above- and belowground respiration. The fluxes were standardized to light and temperature. Gross ecosystem photosynthesis was primarily related to soil moisture and secondarily to plant functional traits and aboveground biomass, and belowground respiration was dependent on the community weighted mean of specific leaf area (SLACWM). Similarly, microbial activity was linked with SLACWM and was highest in meadows, and carbon-degrading microbial activity decreased with vegetation woodiness. These results suggest that shrub expansion may influence summer C cycling differently depending on plant community, as belowground respiration might increase in the heath and decrease in the meadow communities.
TL;DR: This article showed that reindeer grazing can inhibit shrubification of arctic tundra, but grazing impacts on mire mire can be significant in the arctic environment.
Abstract: Shrubification of arctic tundra is a well-recognized phenomenon, and it can be particularly rapid in moist habitats. Reindeer grazing can inhibit shrubification, but grazing impacts on mire...
TL;DR: The results show that the vegetation of glacier forelands is developing rapidly depending on the plant species in the surrounding area and the species’ life-history traits.
Abstract: Recently developed glacier forelands provide valuable insights into vegetation dynamics. We studied the vascular plants in the glacier forelands of the Almajallojekna glacier in comparison to the p...
TL;DR: In this article, the authors experimentally increased summertime temperature and precipitation for three seasons and quantified community responses with a climatic niche analysis, finding that thermophilization occurred in response to experimental heating, and if this effect was ameliorated by experimental watering.
Abstract: A warming climate has been shown to drive thermophilization—shifts in species abundance toward those adapted to warm and dry conditions. The community dynamics shaping this process have been proposed to vary between temperature-limited alpine plant communities and those that are both temperature and moisture limited. In nine sites across the xeric alpine zone in the White Mountains, California, USA, we experimentally increased summertime temperature and precipitation for three seasons and quantified community responses with a climatic niche analysis. We asked if thermophilization occurred in response to experimental heating, and if this effect was ameliorated by experimental watering. Under experimentally warmer conditions, we found no change in the mean community-weighted climatic niche (CCN); however, thermophilization of this community was observed based on a shift in the seventy-fifth percentile of the CCN and an increase in the proportional abundance of the hottest, driest adapted species. In addition, total vegetation abundance increased and species richness decreased with heating. Experimental watering did not ameliorate these effects of heating. Together, these results suggest that warming in arid alpine areas may result in less diverse plant communities dominated by hot, dry associated species, although short-term responses may be limited because of community lags.
TL;DR: In this paper, the authors examined how a remotely sensed proxy of vegetation productivity varied among mountai in northwestern Canada and Alaska during a period of rapid climate change and high-latitude systems.
Abstract: High-latitude systems in northwestern Canada and Alaska have warmed rapidly. The aim of this study was to examine how a remotely sensed proxy of vegetation productivity varied among mountai...
TL;DR: In this article, the authors studied the effects of weathering caused by interaction between glacial sediments and water in exposed moraines on the global carbon cycle, and proposed a method to evaluate their possible effects.
Abstract: Weathering caused by interaction between glacial sediments and water in exposed moraines needs to be studied to evaluate their possible effects on the global carbon cycle. In this study, mo...
TL;DR: Pollen grains are commonly found in ice cores, particularly those from mountain glaciers at low to middle latitudes as mentioned in this paper, because the release of pollen from flowers has a seasonality and varies among different regions of the world.
Abstract: Pollen grains are commonly found in ice cores, particularly those from mountain glaciers at low to middle latitudes. Because the release of pollen from flowers has a seasonality and varies among th...
TL;DR: The north and east slopes of Mount Rainier, Washington, are host to three of the largest glaciers in the contiguous United States: Carbon Glacier, Winthrop Glacier, and Emmons Glacier as discussed by the authors.
Abstract: The north and east slopes of Mount Rainier, Washington, are host to three of the largest glaciers in the contiguous United States: Carbon Glacier, Winthrop Glacier, and Emmons Glacier. Each has an ...
TL;DR: The alpine ecosystem of the Rocky Mountains is experiencing significant increases in growing season length, summer maximum temperatures, and shifting patterns in precipitation as discussed by the authors, and the alpine ecosystems are experiencing significant changes in growing seasons.
Abstract: The alpine ecosystem of the Rocky Mountains is experiencing significant increases in growing season length, summer maximum temperatures, and shifting patterns in precipitation. Alpine herbs...
TL;DR: In this article, the performance of wind forecasts over Svalbard, located between the Arctic Ocean and the Norwegian Sea, was evaluated using the Polar Weather Research and Forecasting (PWRF) model.
Abstract: In this study, the performance of wind forecasts over Svalbard, located between the Arctic Ocean and the Norwegian Sea, was evaluated using the Polar Weather Research and Forecasting (PWRF) model a...
TL;DR: The authors conducted a 2 m snow pit study in July 2017 at the East GRIP (Greenland Ice-Core Project; northeastern Greenland) deep ice-coring site and collected snow samples at intervals of 0.05 m.
Abstract: We conducted a 2 m snow pit study in July 2017 at the East GRIP (Greenland Ice-Core Project; northeastern Greenland) deep ice-coring site. We collected snow samples at intervals of 0.05 m and analy...
TL;DR: In this article, the authors detail variations in the weight percent (wt%) of quartz, a proxy for drift ice, in fifteen marine sediment cores from the northwest, west, and southwest Iceland shelf.
Abstract: We detail variations in the weight percent (wt%) of quartz, a proxy for drift ice, in fifteen marine sediment cores from the northwest, west, and southwest Iceland shelf throughout the past 10 cal ...
TL;DR: Gravelpit lakes are a common feature of many human-modified landscapes throughout the world as mentioned in this paper and they are often formed when gravel is extracted to construct dams, bridges, and highw...
Abstract: Gravel-pit lakes are a common feature of many human-modified landscapes throughout the world. In Canada’s north, they are often formed when gravel is extracted to construct dams, bridges, and highw...
TL;DR: In this paper, the authors evaluate visible-near-infrared spectroscopy (vis-NIRS) for the prediction of carbon emissions from high-latitude soils to the atmosphere.
Abstract: Release of carbon from high-latitude soils to the atmosphere may have significant effects on Earth’s climate. In this contribution, we evaluate visible–near-infrared spectroscopy (vis-NIRS)...
TL;DR: In this article, the impacts of sustained glacier loss are quantified by mapping a complete map of the glaciers in mountainous regions. But the authors did not consider the effects of glacier loss on hydrology, vegetation, and wildlife.
Abstract: Glaciers have significant influence on hydrology, vegetation, and wildlife in mountainous regions, and are receding globally. To quantify the impacts of sustained glacier loss, we mapped a complete...
TL;DR: This work set up transects along environmental gradients in the arctic-alpine ecosystems of Norway and analyzed using a random forest approach to identify the relative importance of topographic position, elevation, and study region on body size of P. palustris, finding that research region was the best explanatory variable.
Abstract: Body size is one of the most important individual traits, determining various other life-history traits, including fitness. Both evolutionary and ecological factors shape the body size in a...
TL;DR: In this paper, the authors reveal contradictory responses of primary producers in Arctic lakes to increasing temperatures, making it unclear how future warming and climate change will alter lake produc......
Abstract: Research has revealed contradictory responses of primary producers in Arctic lakes to increasing temperatures, making it unclear how future warming and climate change will alter lake produc...
TL;DR: Since the 1960s, warming air and sea surface temperatures have led to decreasing sea ice extent and longer periods of open water in the Canadian Arctic Archipelago (CAA), together with chan...
Abstract: Since the 1960s, warming air and sea surface temperatures have led to decreasing sea ice extent and longer periods of open water in the Canadian Arctic Archipelago (CAA), together with chan...