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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 A co-management body formed to make a plan, which was developed in 2003 but never ratified and is now considered out-of-date.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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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...
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...
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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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...
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Throughout the Arctic most pregnant polar bears (Ursus maritimus) construct maternity dens in seasonal snowdrifts that form in wind-shadowed areas. We developed and verified a spatial snowdrift polar bearden habitat model (SnowDens-3D) that predicts snowdrift locations and depths along Alaska’s Beaufort Sea coast. SnowDens-3D integrated snow physics, weather data, and a high-resolution digital elevation model (DEM) to produce predictions of the timing, distribution, and growth of snowdrifts suitable for polar bear dens. SnowDens-3D assimilated 18 winters (1995 through 2012) of observed daily meteorological data and a 2.5 m grid-increment DEM covering 337.5 km2 of the Beaufort Sea coast, and described the snowdrift...
In Alaska, changes in snow, ice, and weather, have resulted in risks to human lives, infrastructure damage, threats to valuable natural resources, and disruption of hunting, fishing, and livelihoods.Leaders from the Aleutians to the Chukchi Sea came together for a series of Coastal Resilience and Adaptation Workshops, spearheaded by three Landscape Conservation Cooperatives and the Aleutian Pribilof Islands Association. Tribal leaders, resource managers, community planners, and scientists explored strategies to adapt to these unprecedented changes.The workshop series brought together 14 Organizing Partners 34 Tribes, 15 State & Federal Agencies, and a total of more than 200 participants to meet in four regional...
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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Spawning migrations of Pacific salmon (Oncorhynchus spp.) to coastal watersheds provide a rich resource subsidy to freshwater consumers. However, variation in thermal regimes and spawning activity across the landscape constrain the ability of poikilothermic consumers to assimilate eggs and carcasses. We investigated how sockeye salmon (Oncorhynchus nerka) spawning density and stream temperature affect the growth, body condition, and fatty acid composition of juvenile coho salmon (Oncorhynchus kisutch), a known egg predator, in seven tributaries of the Wood River in Southwest Alaska. We compared mean body size of juvenile coho salmon in late summer among 3–7 years per stream and found that the largest mean size occurred...
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An important unresolved question is how populations of coldwater-dependent fishes will respond to rapidly warming water temperatures. For example, the culturally and economically important group, Pacific salmon (Oncorhynchus spp.), experience site-specific thermal regimes during early development that could be disrupted by warming. To test for thermal local adaptation and heritable phenotypic plasticity in Pacific salmon embryos, we measured the developmental rate, survival, and body size at hatching in two populations of sockeye salmon (Oncorhynchus nerka) that overlap in timing of spawning but incubate in contrasting natural thermal regimes. Using a split half-sibling design, we exposed embryos of 10 families...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Academics & scientific researchers, CLIMATE CHANGE IMPACT ASSESSMENT MODELS, CLIMATE CHANGE IMPACT ASSESSMENT MODELS, DATA REFORMATTING, DATA REFORMATTING, All tags...
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Intraspecific variation in the seasonal reproductive timing of Pacific salmon (Oncorhynchus sp.) has importantimplications for the resilience of salmon and for organisms in freshwater and terrestrial communities that dependon salmon resources. Stream temperature has well known associations with salmon spawn timing buthow stream and watershed geomorphology relates to the variation in salmon spawn timing is less understood.We used multivariate statistics applied to five environmental variables to compare conditions across36 watersheds in the Wood River basin in southwest Alaska. We found that the environmental conditionsin the first two axes of a principal components analysis (PCA) explained 76% of the variation in...
    map background search result map search result map Linking North Slope of Alaska climate, hydrology, and fish migration Modeling snowdrift habitat for polar bear dens Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. Rapid and highly variable warming of lake surface waters around the globe Association between geomorphic attributes of watersheds, water temperature, and salmon spawn timing in Alaskan streams Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature Thermal adaptation and phenotypic plasticity in a warming world: Insights from common garden experiments on Alaskan sockeye salmon Thermal constraints on stream consumer responses to a marine resource subsidy 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 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 Thermal adaptation and phenotypic plasticity in a warming world: Insights from common garden experiments on Alaskan sockeye salmon Modeling snowdrift habitat for polar bear dens Watershed geomorphology and snowmelt control stream thermal sensitivity to air temperature. Association between geomorphic attributes of watersheds, water temperature, and salmon spawn timing in Alaskan streams 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 Thermal constraints on stream consumer responses to a marine resource subsidy 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