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The Yukon North Slope is an arctic “hot spot” of climate change-induced effects with profound significance for the Inuvialuit and the larger region. In 1984, the Inuvialuit entered into a land claim agreement – the Inuvialuit Final Agreement (IFA) – with the governments of Canada, Yukon and Northwest Territories. A co-management body formed to make a plan, which was developed in 2003 but never ratified and is now considered out-of-date. Round River Conservation Studies is assisting WMAC(NS) in the collection, development and synthesis of spatial data, models and analyses of cultural and ecological values of the YNS.The project is a collaboration among the NWB LCC, Round River Conservation Studies, and the Arctic...
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Arctic grayling (Thymallus arcticus) have a life-history strategy specifically adapted to the extreme climate of the North. These fish migrate to spawning grounds just after breakup in the spring, then migrate to feeding sites in early summer, and finally in the fall migrate back to their overwintering sites. The Kuparuk River is a perennial stream originating in the northern foothills of the Brooks Range on the North Slope of Alaska. Sections of the Kuparuk are periodically intermittent in that, during low flows in the system, these channel reaches appear dry. The flow varies between surface and subsurface in this permafrost-dominated environment, with subsurface flow being limited to the unfrozen thaw bulb around...
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Watersheds draining the Arctic Coastal Plain (ACP) of Alaska are dominated by permafrostand snowmelt runoff that create abundant surface storage in the form of lakes, wetlands, and beaded streams. These surface water elements compose complex drainage networks that affect aquatic ecosystem connectivity and hydrologic behavior. The 4676 km2 Fishand Creek drainage basin is composed of three watersheds that represent a gradient of theACP landscape with varying extents of eolian, lacustrine, and fluvial landforms. In each watershed, we analyzed 2.5-m-resolution aerial photography, a 5-m digital elevationmodel, and river gauging and climate records to better understand ACP watershed structureand processes. We show that...
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There is a great deal of interest in whether and how Alaska’s precipitation is changing but little agreement in the existing peer-reviewed literature. To provide insight on this question, we have selected three commonly used 0.5° resolution gridded precipitation products that have long-term monthly data coverage (Climatic Research Unit TS3.10.1, Global Precipitation Climatology Centre Full Data Reanalysis version 5, and University of Delaware version 2.01) and evaluated their homogeneity and trends with multiple methods over two periods, 1950–2008 and 1980–2008. All three data sets displayed common broadscale features of Alaska’s precipitation climatology, but there were substantial differences between them in terms...
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Floods, spatially complex water flows, and organism movements all generate important fluxes of aquatic-derived materials into terrestrial habitats, counteracting the gravity-driven downhill transport of matter from terrestrial-to-aquatic ecosystems. The magnitude of these aquatic subsidies isoften smaller than terrestrial subsidies to aquatic ecosystems but higher in nutritional quality, energy density, and nutrient concentration. The lateral extent of biological aquatic subsidies is typically small, extending only a few meters into riparian habitat; however, terrestrial consumers often aggregate on shorelines to capitalize on these high-quality resources. Although the ecological effects of aquatic subsidies remain...
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How local geomorphic and hydrologic features mediate the sensitivity of stream thermal regimes to variation in climatic conditions remains a critical uncertainty in understanding aquatic ecosystem responses to climate change. We used stable isotopes of hydrogen and oxygen to estimate contributions of snow and rainfall to 80 boreal streams and show that differences in snow contribution are controlled by watershed topography. Time series analysis of stream thermal regimes revealed that streams in rain-dominated, low-elevation watersheds were 5–8 times more sensitive to variation in summer air temperature compared to streams draining steeper topography whose flows were dominated by snowmelt. This effect was more pronounced...
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Interactions and feedbacks between abundant surface waters and permafrost fundamentally shapelowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceedslake depth and mean annual bed temperatures (MABTs) remain below freezing. However, decliningMIT since the1970s is likely causing talik development below shallow lakes. Here we show high-temperature sensitivity towinter ice growth at the water-sediment interface of shallow lakes based on year-round lake sensor data.Empirical model experiments suggest that shallow (1m depth) lakes have warmed substantially over the last30years (2.4°C), withMABT above freezing5 of the last 7years.This is incomparison to slower ratesofwarming...
The tundra biome is the dominant terrestrial ecosystem of the circumpolar north, and its fate in a rapidly changing climate is of high scientific and socioeconomic concern. One of those concerns is that the majority of caribou herds throughout the circumpolar north are declining, perhaps as a result of climate change. The principal objective of this research is to reveal the connections between soil nutrient cycling, forage quality and caribou habitat selection. This framework is underpinned by the concept that tundra ecosystem productivity is ultimately driven by the thermodynamics of the system induced by climate.
Categories: Data, Publication; Types: Citation; Tags: ALPINE/TUNDRA, ALPINE/TUNDRA, CARBON, CARBON, CARBON CYCLE/CARBON BUDGET MODELS, All tags...
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In this first worldwide synthesis of in situ and satellite-derived lake data, we find that lakesummer surface water temperatures rose rapidly (global mean = 0.34°C decade1) between 1985 and2009. Our analyses show that surface water warming rates are dependent on combinations of climate andlocal characteristics, rather than just lake location, leading to the counterintuitive result that regionalconsistency in lake warming is the exception, rather than the rule. The most rapidly warming lakes are widelygeographically distributed, and their warming is associated with interactions among different climatic factors—from seasonally ice-covered lakes in areas where temperature and solar radiation are increasing whilecloud...
An integrated high resolution tide and storm surge model has been developedfor all of coastal Alaska. The model uses the ADCIRC basin-to-channelscale unstructured grid circulation code. Tidal forcing from global tidal modelsand meteorological forcing from the Climate Forecast System Reanalysisare used. The model’s tidal solution has been validated at 121 shelf andnearshore stations. The model’s skill has been investigated for summer, falland winter storms. Sea ice has been incorporated through a parameterizedwind drag coefficient which modifies the air-sea drag under ice coverage.Three large storms with distinctly different ice coverages were chosen to exhibitthe effect of sea ice on the resulting storm surge. The...
Categories: Data, Publication; Types: Citation; Tags: Academics & scientific researchers, COASTAL AREAS, COASTAL AREAS, COASTAL PROCESSES, COASTAL PROCESSES, All tags...
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Many Arctic shorebird populations are declining, and quantifying adult survival and the effects of anthropogenic factorsis a crucial step toward a better understanding of population dynamics. We used a recently developed, spatially explicitCormack–Jolly–Seber model in a Bayesian framework to obtain broad-scale estimates of true annual survival rates for 6species of shorebirds at 9 breeding sites across the North American Arctic in 2010–2014. We tested for effects ofenvironmental and ecological variables, study site, nest fate, and sex on annual survival rates of each species in thespatially explicit framework, which allowed us to distinguish between effects of variables on site fidelity versus truesurvival. Our...
The Adapt Alaska Collaborative grew out of a set of initiatives to promote climate resilience and adaptation in Alaska. On May 24 and 25, 2017 a group of participants (including representatives of Alaska regional, state and federal agencies and organizations) gathered at a work session to identify next steps to build on the momentum generated by these initiatives toward a more resilient Alaska. At the work session, three working groups formed around specific areas of effort, including a Planning Working Group with the task of identifying ways to streamline the many planning requirements associated with implementing climate resilience and adaptation strategies.The Adapt Alaska Planning Working Group looked at a range...
Categories: Data, Publication; Types: Citation; Tags: Academics & scientific researchers, Aleutian Bering Sea Islands LCC data.gov, CLIMATE ADVISORIES, CLIMATE ADVISORIES, CLIMATE INDICATORS, All tags...
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This paper explores the impacts of shrinking glaciers on downstream ecosystems in the Arctic National Wildlife Refuge. Glaciers here are losing mass at an accelerating rate and will largely disappear in the next 50–100 years if current trends continue. We believe this will have a measurable and possibly important impact on the terrestrial and estuarine ecosystems and the associated bird and fish species within these glaciated watersheds.
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Lakes are dominant and diverse landscapefeatures in the Arctic, but conventional land coverclassification schemes typically map them as a singleuniform class. Here, we present a detailed lake-centricgeospatial database for an Arctic watershed in northernAlaska. We developed a GIS dataset consisting of 4362lakes that provides information on lake morphometry,hydrologic connectivity, surface area dynamics,surrounding terrestrial ecotypes, and other importantconditions describing Arctic lakes. Analyzing thegeospatial database relative to fish and bird survey datashows relations to lake depth and hydrologic connectivity,which are being used to guide research and aid in themanagement of aquatic resources in the NationalPetroleum...
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The Arctic Coastal Plain (ACP) of northern Alaskaconsists of an extremely low gradient, lake-richlandscape that is characterized by a complex networkof aquatic habitats and surface features stronglyinfluenced by permafrost dynamics. Much is unknownabout the form, function, and ecological conditions inthis unique hydrologic setting. Amplified climatechange and landscape responses in the Arctic furthercomplicate the capacity to separate natural variabilityfrom land use effects that may occur with petroleumdevelopment. A comprehensive, multi-disciplinaryreview and analysis of recent studies and initialinventory and monitoring in the Fish Creek watershedon the ACP provided guidance to develop a frameworkfor future aquatic...
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Numerous studies have evaluated precipitation trends in Alaska and come to different conclusions. These studies differ in analysis period and methodology and do not address the issue of temporal homogeneity. To reconcile these conflicting results, we selected 29 stations with largely complete monthly records, screened them for homogeneity, and then evaluated trend over two analysis periods (1950–2010 and 1980–2010) using three methods: least absolute deviation regression, ordinary least squares regression (with and without transformation), and Mann-Kendall trend testing following removal of first-order autocorrelation. We found that differences in analytical period had a significant impact on trends and that the...
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The Yukon–Kuskokwim Delta of Alaska,USAis a globally important region for numerous avianspecies including millions of migrating and nesting waterbirds.However, data on the current spatial distributionof critical nesting areas and the importance of environmental variables in the selection of nest locations aregenerally lacking for waterbirds in this region.We modeled nest densities for 6 species of geese and eiders thatcommonly breed on the Yukon–Kuskokwim Delta, including cackling goose (Branta hutchinsii minima),emperor goose (Chen canagica), black brant (B. bernicla nigricans), greater white-fronted goose (Anser albifronsfrontalis), spectacled eider (Somateria fischeri), and common eider (S. mollissima).Thedata...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: BIRDS, BIRDS, CLIMATE CHANGE IMPACT ASSESSMENT MODELS, CLIMATE CHANGE IMPACT ASSESSMENT MODELS, DELTAS, All tags...
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When resources are spatially and temporally variable, consumers can increasetheir foraging success by moving to track ephemeral feeding opportunitiesas these shift across the landscape; the best examples derive from herbivore–plant systems, where grazers migrate to capitalize on the seasonal waves ofvegetation growth. We evaluated whether analogous processes occur in watershedssupporting spawning sockeye salmon (Oncorhynchus nerka), askingwhether seasonal activities ofpredators and scavengers shift spatial distributionsto capitalize on asynchronous spawning among populations of salmon. Bothglaucous-winged gulls and coastal brown bears showed distinct shifts in theirspatial distributions over the course of the summer,...
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Global environmental change has influenced lake surface temperatures, a key driver of ecosystem structureand function. Recent studies have suggested significant warming of water temperatures in individual lakesacross many different regions around the world. However, the spatial and temporal coherence associatedwith the magnitude of these trends remains unclear. Thus, a global data set of water temperature isrequired to understand and synthesize global, long-term trends in surface water temperatures of inlandbodies of water. We assembled a database of summer lake surface temperatures for 291 lakes collectedin situ and/or by satellites for the period 1985–2009. In addition, corresponding climatic drivers (airtemperatures,...
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How local geomorphic and hydrologic features mediate the sensitivity of stream thermal regimesto variation in climatic conditions remains a critical uncertainty in understanding aquatic ecosystem responsesto climate change.We used stable isotopes of hydrogen and oxygen to estimate contributions of snow and rainfallto 80 boreal streams and show that differences in snow contribution are controlled by watershed topography.Time series analysis of streamthermal regimes revealed that streams in rain-dominated, low-elevation watershedswere 5–8 times more sensitive to variation in summer air temperature compared to streams draining steepertopography whose flows were dominated by snowmelt. This effect wasmore pronounced...
map background search result map search result map Linking North Slope of Alaska climate, hydrology, and fish migration Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate A lake-centric geospatial database to guide research and inform management decisions in an Arctic watershed in northern Alaska... Reconciling precipitation trends in Alaska: 2. Gridded data analyses Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. Rapid and highly variable warming of lake surface waters around the globe Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature Riding the crimson tide: mobile terrestrial consumers track phenological variation in spawning of an anadromous fish Subsidies of Aquatic Resources in Terrestrial Ecosystems A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Predicting the Impact of Glacier Loss Reconciling precipitation trends in Alaska: 1. Station-based analyses Developing a Long-term Aquatic Monitoring Network Developing a Long-Term Aquatic Monitoring Network in a Complex Watershed of the Alaskan Arctic Coast Predicting Waterbird Nest Distributions on the Yukon–Kuskokwim Delta of Alaska Yukon North Slope Wildlife Management Plan Linking North Slope of Alaska climate, hydrology, and fish migration Predicting Waterbird Nest Distributions on the Yukon–Kuskokwim Delta of Alaska Predicting the Impact of Glacier Loss Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate A lake-centric geospatial database to guide research and inform management decisions in an Arctic watershed in northern Alaska... Drainage Network Structure and Hydrologic Behavior of Three Lake-Rich Watersheds on the Arctic Coastal Plain, Alaska Developing a Long-term Aquatic Monitoring Network Developing a Long-Term Aquatic Monitoring Network in a Complex Watershed of the Alaskan Arctic Coast Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. Riding the crimson tide: mobile terrestrial consumers track phenological variation in spawning of an anadromous fish Rapid and highly variable warming of lake surface waters around the globe Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature Subsidies of Aquatic Resources in Terrestrial Ecosystems A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 Yukon North Slope Wildlife Management Plan Reconciling precipitation trends in Alaska: 2. Gridded data analyses Reconciling precipitation trends in Alaska: 1. Station-based analyses Environmental and ecological conditions at Arctic breeding sites have limited effects on true survival rates of adult shorebirds