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Filters: Tags: {"type":"Harvest Set","name":"western alaska landscape conservation cooperative data.gov"} (X) > partyWithName: U.S. Geological Survey (X)

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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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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...
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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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This report is structured around the specific objectives in the format of three stand-alone manuscripts that are in the process of submission to peer-reviewed journals. The first manuscript includes objectives 1-2, the second manuscript addresses objective 3, and the final manuscript objective 4. The overarching goal of the proposal was to understand how both recently experienced and projected water temperatures might influence population-specific patterns of embryo incubation, timing of hatching and fry emergence, and survival of sockeye salmon embryos. Additionally, we sought to explore the potential for adaptation in a heritable threshold life history trait that shapes whether an individual migrates to the ocean...
Categories: Data; Types: 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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Webinar 2015: Alaska’s National Hydrography Dataset (NHD), the digital data layer that depicts the location of lakes and streams, was originally created from the 1950’s topographic maps. With funding support from the LCC Network, this project focused on establishing a statewide framework to improve the hydrography mapping and stewardship in Alaska. This will be achieved through the creation of a statewide system to make digital mapping data updates accessible and affordable, and through the creation of a statewide hydrography mapping coordinator position to synchronize updates and guide hydrography mapping development. This framework will allow agencies and organizations to greatly improve their hydrography mapping...
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Southwest Alaska is one of the fastest warming regions on Earth and its aquatic resources are at distinct risk from changing climate. Previous work has demonstrated that a variety of physical and biological processes are sensitive to changing climate regimes in this region, including those that support wildlife and fisheries that are of substantial importance for subsistence and commercial activities. This collaborative project resulted in the compilation of a database of existing stream, river and lake temperatures that is unmatched anywhere else in Alaska in terms of its spatial and temporal coverage. Analysis of these data resulted in refinement of the monitoring plan developed to characterize thermal responses...
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Webinar 1: Alaska’s National Hydrography Dataset (NHD), the digital data layer that depicts the location of lakes and streams, was originally created from the 1950’s topographic maps. With funding support from the LCC Network, this project focused on establishing a statewide framework to improve the hydrography mapping and stewardship in Alaska. This will be achieved through the creation of a statewide system to make digital mapping data updates accessible and affordable, and through the creation of a statewide hydrography mapping coordinator position to synchronize updates and guide hydrography mapping development. This framework will allow agencies and organizations to greatly improve their hydrography mapping...
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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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This strategic plan is a guiding framework that lays out the objectives and goals for Alaska Hydrology Technical Working Group and AK Hydro to accomplish high-resolution statewide hydrography updates that meet national mapping standards and local partners’ needs.The strategic plan identifies five key objec-tives: 1) Map Alaska’s Water 2) Support Alaska’s Hydrography Needs 3) provide Hydrography Services 4) establish a Sus-tainable Hydrography future and 5) allow for Data Integration. These strategic objectives will give AK Hydro and AHTWG success in meeting the mission to efficiently serve the hydrography needs of Alaska. The objectives as-sist in mapping the surface water of Alaska, meeting NHD standards, securing...
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Alaska is an expansive state with abundant water resources. The complex landscape is defined by water and ice, but Alaska lacks quality mapping of its surface water features. The Alaska Hydrography Technical Working Group and Alaska Hydrography Database have worked to establish the Alaska Hydrography Strategic Plan to promote and guide a core mission to efficiently serve the current and future hydrography needs of Alaska for the next five years. This work will update the state’s hydrography in the National Hydrography Database from its current condition to meet national 1:24,000-scale standards. This work has focused on coordination of hydrography needs with partners and land managers, planning for the future hydrography...
    map background search result map search result map Rapid and highly variable warming of lake surface waters around the globe 2014 Webinar for Bringing Alaska's Hydrology into the 21st Century 2015 Webinar: Bringing Alaska's Freshwater Hydrography into the 21st Century 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 Webinar: Effects of winter climate and watershed features on summer stream temperatures in Bristol Bay, Alaska Final Report Water Temperature Regimes in the Togiak NWR and Wood-Tikchik State Park Final Report: Temperature, phenology, and embryo survival in Western Alaska sockeye salmon populations: the potential for adaptation to a warming worl Bringing Alaska’s Freshwater Hydrography into the 21st Century Alaska Hydrography Strategic Plan: Mapping Alaska's Water 2017-2021 Subsidies of Aquatic Resources in Terrestrial Ecosystems A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 Lidar processing and Survey Reports Thermal adaptation and phenotypic plasticity in a warming world: Insights from common garden experiments on Alaskan sockeye salmon Final Report: Temperature, phenology, and embryo survival in Western Alaska sockeye salmon populations: the potential for adaptation to a warming worl Lidar processing and Survey Reports 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 Webinar: Effects of winter climate and watershed features on summer stream temperatures in Bristol Bay, Alaska Final Report Water Temperature Regimes in the Togiak NWR and Wood-Tikchik State Park Subsidies of Aquatic Resources in Terrestrial Ecosystems A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009 2014 Webinar for Bringing Alaska's Hydrology into the 21st Century 2015 Webinar: Bringing Alaska's Freshwater Hydrography into the 21st Century Bringing Alaska’s Freshwater Hydrography into the 21st Century Alaska Hydrography Strategic Plan: Mapping Alaska's Water 2017-2021