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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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Snow is extremely important to a wide range of natural processes in Alaska. Snow cover helps regulate the earth’s temperature and stores water on the landscape. As it melts, snow hydrates the soil and replenishes the freshwater supplies of streams and lakes, providing water for vegetation, wildlife, and human activities such as agriculture and electricity generation. Understanding present and future snow conditions under climate change is critical for managing Alaska’s natural resources, yet many scientists, land managers, and policymakers lack this information at useful scales. Hence, the goal of this project was to produce an advanced snow modeling system for part of the Arctic that predicts a variety of factors...
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As temperature and precipitation patterns change in Alaska, the need for scientific information to inform decision making related to the management of our natural resources becomes ever more important. However, the research being conducted to understand potential future impacts of climate change in Alaska frequently results in output and products that, in their raw forms, are not easily used by stakeholders and partners or are somewhat removed from the direct information needs of natural resource decision makers. This project broadly aims to evaluate the information needs of regional stakeholders and partners; conduct “translational” activities to make archived historical data, modeled output, and future projections...
This report describes the progress made by the Integrated Ecosystem Model (IEM) for Alaska and Northwest Canada Project for the full duration of the project (September 1, 2011 through August 31, 2016).This primary goal in this project was to develop the IEM modeling framework to integrate the driving components for and the interactions among disturbance regimes, permafrost dynamics, hydrology, and vegetation succession/migration for Alaska and Northwest Canada. The major activities of the project include (1) development and delivery of input data sets, (2) model coupling, (3) evaluation and applications of fire and vegetation dynamics, (4) evaluation and application of ecosystem carbon and energy balance, (5) evaluation...
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The observed rate of warming in many National Park Service (NPS) lands in Alaska has accelerated soil subsidence and increased landslide frequency, thereby threatening public access, subsistence activities and infrastructure in NPS regions. Areas most affected by this change are along the Denali Park Road, the proposed Ambler Road through Gates of the Arctic National Park and Preserve, and the McCarthy Road in Wrangell – St. Elias National Park and Preserve. In light of this, resource managers need highly accurate, localized climate information to assess and plan for future landslide hazards. This project addresses concerns and management implications in these focus areas with emerging issues that have been outlined...
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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...
Explore thousands of curated scholarly articles, state and federal resource reports, land management plans, and more in the Northwest Boreal Landscape Conservation Cooperative bibliography. The tool allows users to search by keyword and geography to find relevant documents (i.e., peer-reviewed journal articles, government reports, land use management plans, dissertations, theses, etc.) across the boreal.
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://www.nature.com/nature/journal/v520/n7546/full/nature14338.html): Large quantities of organic carbon are stored in frozen soils (permafrost) within Arctic and sub-Arctic regions. A warming climate can induce environmental changes that accelerate the microbial breakdown of organic carbon and the release of the greenhouse gases carbon dioxide and methane. This feedback can accelerate climate change, but the magnitude and timing of greenhouse gas emission from these regions and their impact on climate change remain uncertain. Here we find that current evidence suggests a gradual and prolonged release of greenhouse gas emissions in a warming climate and present a research strategy with which to...
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...
Climate change is expected to alter the frequencies and intensities of at least some types of extreme events. Although Alaska is already experiencing an amplified response to climate change, studies of extreme event occurrences have lagged those for other regions. Forced migration due to coastal erosion, failing infrastructure on thawing permafrost, more severe wildfire seasons, altered ocean chemistry, and an ever-shrinking season for snow and ice are among the most devastating effects, many of which are related to extreme climate events. This study uses regional dynamical downscaling with the Weather Research and Forecasting (WRF) Model to investigate projected twenty-first-century changes of daily maximum temperature,...
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%...
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In the Gulf of Alaska, streams will experience more dramatic low water events, interspersed with larger and potentially more frequent high flow events in the coming decades. Reduced stream flows are likely to occur due to diminished snowpack and seasonal droughts, while higher flow events are likely to occur with more frequent storms and rain-on-snow events. These changes are likely to influence the growth trajectories of juvenile salmon, such as coho salmon and chinook salmon, that live up to two years in freshwater before migrating to the ocean. Stream flows can influence juvenile salmon growth by modifying food availability, water clarity, temperature, and predation risk. This high-resolution study examines...
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Salmon runs are an important time when salmon migrate from the ocean to freshwater, swimming upriver to reach spawning beds. These annual events provide an important food source for both predators and for local communities. However, Recent declines in salmon runs have caused hardship in subsistence fishing communities throughout Alaska, particularly in the Yukon River Basin. To adapt to a changing climate, fishing communities, natural resource managers, and scientists need to measure and understand climate impacts onto salmon runs in this region. To monitor changes in salmon populations and manage fisheries, the Alaska Department of Fish and Game (ADFG), U.S. Fish and Wildlife Service (USFWS), and Tanana Chiefs...
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Water temperature plays a large role in freshwater ecosystems in the Arctic and sub-Arctic. It affects the physical and biological features of rivers, like how the water interacts with the landscape and the life cycles of organisms that live in the river. For example, unseasonably warm water temperatures in Alaska’s large rivers in 2019 caused large numbers of salmon to die before they could reach their spawning grounds. Though water temperature data is important for natural resources monitoring programs, these data are historically lacking and hard to collect for large river systems. Satellites and other remote sensing techniques can offer valuable insight to Alaskan stream conditions. They can measure thermal...
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In the last decade, the annual area burned by wildfires in Alaska has doubled relative to any of the previous four decades, and the current frequency of fire is unprecedented over the past 1,200 years. Wildland fires are one of the main contributors to long-term changes in the structure and function of boreal and subarctic ecosystems. Although fire is a necessary component of regulating these ecosystems, it also poses a hazard to humans when uncontrolled. Currently, fire managers use the Fire Behavior Prediction Calculator to perform calculations that can assist in field management of fires, but the only version of this tool that is available depends on network access, which poses a significant limitation for...
map background search result map search result map Modeling and Predicting Future Changes in Snowfall and Snow Cover in Alaska Translating Scientific Information for Use by Decision Makers in Alaska Climate Adaptation in Yukon River Fisheries: A Robust Alternative Approach to Assess Salmon Run Size Using Environmental DNA Assessing the Risk to National Park Service Lands in Alaska Imposed by Rapidly Warming Temperatures Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making The Influence of Stream Flow Patterns on Juvenile Salmon Growth in Southeast Alaska A Mobile Fire Behavior Prediction Calculator to Inform Fire Management in Alaska Compilation of Historical Water Temperature Data for Large Rivers in Alaska using the Landsat Satellite Archive Assessment of Critical Landscape Conditions and Potential Change in the Coastal Plain of the Arctic National Wildlife Refuge to Support Habitat Management Decision Making Modeling and Predicting Future Changes in Snowfall and Snow Cover in Alaska Assessing the Risk to National Park Service Lands in Alaska Imposed by Rapidly Warming Temperatures The Influence of Stream Flow Patterns on Juvenile Salmon Growth in Southeast Alaska Translating Scientific Information for Use by Decision Makers in Alaska Climate Adaptation in Yukon River Fisheries: A Robust Alternative Approach to Assess Salmon Run Size Using Environmental DNA A Mobile Fire Behavior Prediction Calculator to Inform Fire Management in Alaska Compilation of Historical Water Temperature Data for Large Rivers in Alaska using the Landsat Satellite Archive