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These data can be used to replicate the application of MWBMglacier as described in two journal articles: 1) Enhancement of a parsimonious water balance model to simulate surface hydrology in a glacierized watershed (in review), and 2) Hydrologic regime changes in a high-latitude glacierized watershed under future climate conditions (doi:10.3390/w10020128). These simulations provide results from historical and 12 future general circulation model scenarios for the period 1949-2099 to determine the potential effects of climate change on the hydrology and water quality of a snow-dominated mountainous environment. In addition to the inputs and outputs, this Data Release includes summaries of the input and output data...
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As glaciers melt from climate change, their contents – namely, large quantities of freshwater, sediment, and nutrients – are slowly released into coastal ecosystems. This project addressed the impacts of melting glaciers on coastal ecosystems in the Copper River region of the Gulf of Alaska, which is home to several commercially important fisheries. Researchers examined how glacial melting is altering the amount and timing of freshwater that enters the Gulf of Alaska from the Copper River. They also investigated the source and amount of two nutrients, iron and nitrate, dissolved in the water. As a complementary piece of the study, researchers tested the relationship between nutrient levels, plankton populations,...
Abstract (from http://www.nature.com/nature/journal/v521/n7551/full/nature14238.html): Over 20% of Earth’s terrestrial surface is underlain by permafrost with vast stores of carbon that, once thawed, may represent the largest future transfer of carbon from the biosphere to the atmosphere1. This process is largely dependent on microbial responses, but we know little about microbial activity in intact, let alone in thawing, permafrost. Molecular approaches have recently revealed the identities and functional gene composition of microorganisms in some permafrost soils2, 3, 4 and a rapid shift in functional gene composition during short-term thaw experiments3. However, the fate of permafrost carbon depends on climatic,...
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Permafrost – the thick layer of permanently frozen soil found in Arctic regions – has been thawing rapidly over the past century due to climate change. When permafrost thaws unevenly, it produces thermokarst landscapes, irregular surfaces of small hills interspersed with hollows. The processes that produce thermokarst can lead to significant changes within the surrounding ecosystems, altering water quality, vegetation, and water, carbon, and nutrient storage and flows. These changes can have substantial implications for fish and wildlife populations and disrupt rural communities and infrastructure. The goal of this project was to better understand the extent of thermokarst processes and the rate at which they...
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Retreating glaciers are an iconic image of climate change;yet not all glaciers in Alaska are actively retreating, and a few glaciers are even advancing. While this contrasting behavior can be misleading for the casual observer, variable responses between glaciers in a changing climate are expected. Glaciers act as conveyor belts that transport snow and ice from high elevations, where it does not melt, down to low elevations, where it does melt. A change in climate can impact the amount of snow and ice that accumulates (accumulation), the way snow and ice melt (ablation), or the conveyor belt (ice dynamics). While these impacts vary with elevation and glacier shape, glacier changes have major implications for downstream...
Abstract (from http://www.sciencedirect.com/science/article/pii/S0309170815002444): The northern portion of the Pacific coastal temperate rainforest (PCTR) is one of the least anthropogenically modified regions on earth and remains in many respects a frontier area to science. Rivers crossing the northern PCTR, which is also an international boundary region between British Columbia, Canada and Alaska, USA, deliver large freshwater and biogeochemical fluxes to the Gulf of Alaska and establish linkages between coastal and continental ecosystems. We evaluate interannual flow variability in three transboundary PCTR watersheds in response to El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Arctic...
Abstract (from http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0132652): Climate warming is likely to cause both indirect and direct impacts on the biophysical properties of stream ecosystems especially in regions that support societally important fish species such as Pacific salmon. We studied the seasonal variability and interaction between stream temperature and DO in a low-gradient, forested stream and a glacial-fed stream in coastal southeast Alaska to assess how these key physical parameters impact freshwater habitat quality for salmon. We also use multiple regression analysis to evaluate how discharge and air temperature influence the seasonal patterns in stream temperature and DO. Mean daily...
Abstract: We present a high-resolution Gravity Recovery and Climate Experiment (GRACE) mascon solution for Gulf of Alaska (GOA) glaciers and compare this with in situ glaciological, climate and other remote-sensing observations. Our GRACE solution yields a GOA glacier mass balance of - 65 ± 11 Gt a - 1 for the period December 2003 to December 2010, with summer balances driving the interannual variability. Between October/November 2003 and October 2009 we obtain a mass balance of - 61 ± 11 Gt a - 1 from GRACE, which compares well with - 65 ± 12 Gt a - 1 from ICESat based on hypsometric extrapolation of glacier elevation changes. We find that mean summer (June - August) air temperatures derived from both ground and...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2014JC010395/full): A study of the freshwater discharge into the Gulf of Alaska (GOA) has been carried out. Using available streamgage data, regression equations were developed for monthly flows. These equations express discharge as a function of basin physical characteristics such as area, mean elevation, and land cover, and of basin meteorological characteristics such as temperature, precipitation, and accumulated water year precipitation. To provide the necessary input meteorological data, temperature and precipitation data for a 40 year hind-cast period were developed on high-spatial-resolution grids using weather station data, PRISM climatologies, and...
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Areas along the Arctic coast are changing the fastest among all of Earth’s habitats due to climate change. The Arctic coast is a fragile ecosystem that provides habitat for migratory birds, endangered species, and species critical for local subsistence living. In this area, permafrost is thawing rapidly, changing how much and when water reaches rivers, ponds, lakes, wetlands and groundwater. In addition, there is also a growing interest in oil and gas resource exploration. With ongoing permafrost thaw, future warming, and interests in oil and gas extraction in the coastal plain (also known as the 1002 area) of the Arctic National Wildlife Refuge, it is urgent to improve the understanding of this area and its vulnerability...
How do glaciers impact Alaska’s coastal ecosystems, and what do glacier changes mean for the future of this ecologically and economically valuable system?
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2014JG002683/abstract): Changes in vegetation and soil properties following permafrost degradation and thermokarst development in peatlands may cause changes in net carbon storage. To better understand these dynamics, we established three sites in Alaska that vary in permafrost regime, including a black spruce peat plateau forest with stable permafrost, an internal collapse scar bog formed as a result of thermokarst, and a rich fen without permafrost. Measurements include year-round eddy covariance estimates of carbon dioxide (CO2 ), water, and energy fluxes, associated environmental variables, and methane (CH4 ) fluxes at the collapse scar bog. The ecosystems...
The large, highly glacierized Copper River basin is an important water resource for the south‐central region of Alaska. Thus, information is needed on the reaction of its hydrologic timing and streamflow volumes to historical changes in climate, in order to assess the possible impact of future changes. However, the basin is remote, and therefore, it has proved difficult to collect field data in a frequent temporal and spatial manner. An extension of the distributed‐parameter, physical‐process code Precipitation Runoff Modeling System, PRMSglacier, has been specifically developed to simulate daily hydrology without requiring extensive input data. In this study, PRMSglacier was used to characterize the hydrology of...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2015JF003789/abstract): A module to simulate glacier runoff, PRMSglacier, was added to PRMS (Precipitation Runoff Modeling System), a distributed-parameter, physical-process hydrological simulation code. The extension does not require extensive on-glacier measurements or computational expense but still relies on physical principles over empirical relations as much as is feasible while maintaining model usability. PRMSglacier is validated on two basins in Alaska, Wolverine, and Gulkana Glacier basin, which have been studied since 1966 and have a substantial amount of data with which to test model performance over a long period of time covering a wide range...
Abstract (from http://link.springer.com/article/10.1007/s10021-014-9777-1): The Coast Mountains of southeast Alaska are currently experiencing some of the highest rates of glacier volume loss on Earth, with unknown implications for proglacial stream biogeochemistry. We analyzed streamwater for δ18O and dissolved organic matter (DOM) biogeochemistry (concentration, δ13C-dissolved organic carbon (DOC), and fluorescence characterization) during the 2012 glacial runoff season from three coastal watersheds in southeast Alaska that ranged in glacier coverage from 0 to 49% and a glacier outflow stream. Our goal was to assess how DOM biogeochemistry may change as receding glaciers are replaced by forests and glaciers contribute...
This publication is a product from the 2011 Alaska CSC supported project "Assessing the Sensitivity of Alaska’s Coastal Rainforest Ecosystems to Changes in Glacier Runoff". Abstract from paper: Iceberg calving is known to release substantial seismic energy, but little is known about the specific mechanisms that produce calving icequakes. At Yahtse Glacier, a tidewater glacier on the Gulf of Alaska, we draw upon a local network of seismometers and focus on 80 hours of concurrent, direct observation of the terminus to show that calving is the dominant source of seismicity. To elucidate seismogenic mechanisms, we synchronized video and seismograms to reveal that the majority of seismic energy is produced during...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/2015JF003539/abstract): A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex terrain due to interactions between topography and meteorological processes. In spring 2013, we measured snow accumulation on several glaciers around the Gulf of Alaska using both ground- and helicopter-based ground-penetrating radar surveys, complemented by extensive ground truth observations. We found that SWE can be highly variable (40%...
map background search result map search result map Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Gulf of Alaska Monitoring Thermokarst on the Landscapes of Northern Alaska Supporting data for two MWBMglacier applications to the Copper River basin in Alaska Assessing the Vulnerability of Alaska’s Glaciers in a Changing Climate Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making Supporting data for two MWBMglacier applications to the Copper River basin in Alaska Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making Impacts of Climate Change and Melting Glaciers on Coastal Ecosystems in the Gulf of Alaska Monitoring Thermokarst on the Landscapes of Northern Alaska Assessing the Vulnerability of Alaska’s Glaciers in a Changing Climate