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River piracy[mdash]the diversion of the headwaters of one stream into another one[mdash]can dramatically change the routing of water and sediment, with a profound effect on landscape evolution. Stream piracy has been investigated in glacial environments, but so far it has mainly been studied over Quaternary or longer timescales. Here we document how retreat of Kaskawulsh Glacier[mdash]one of Canada/'s largest glaciers[mdash]abruptly and radically altered the regional drainage pattern in spring 2016. We use a combination of hydrological measurements and drone-generated digital elevation models to show that in late May 2016, meltwater from the glacier was re-routed from discharge in a northward direction into the...
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EXECUTIVE SUMMARY The persistent environmental contaminants include organochlorine compounds such as the PCBs and pesticides, heavy metals and radioactive elements. They are found at many military sites, mining and oil extraction sites and municipal land fills throughout Alaska. Most however, originate from other parts of the world and make their way here by air, water and even migratory wildlife pathways. Chemically they are very stable and concentrate in the food chain, which serves as the most significant route of exposure to humans. While many traditional foods from many areas of the state have yet to be tested, data that is available indicates levels in traditional foods are not significantly elevated. Nearly...
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A long range dual frequency identification sonar (DIDSON-LR) was used to enumerate the chinook salmon escapement to the Big Salmon River in 2006, as well as determine associated run timing, and diel migration patterns. This was the second year of sonar operation at this site. The sonar site was located on the Big Salmon River at the same location as in 2005, approximately 1.5 km upstream of the confluence with the Yukon River. Partial weirs placed on both sides of the river were used to restrict fish passage through a 34 m opening. The sonar was configured to provide a 29º conical ensonified field, 40 m wide that covered the water column within the fish passage opening. A total of 7,308 (7,298 counted plus 10 extrapolated)...
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The seismic shothole drillers' log database provides baseline, shallow (10-50 m) lithostratigraphic geoscience information on surficial and bedrock geology, hydrogeology, permafrost geology, and geohazards. The revised version 2 database is a greatly enlarged compilation of 275 871 individual, augered shothole drillers' log records collected from 1954 to present. Originally published as Open File 5465, and containing 76 000 records, the version 2 database has been bolstered by tremendous Industry support, wherein the archival holdings of 16 companies have been made available for inclusion. Compiled in a Microsoft Access (super R) database, the shothole data span the length and breadth of the Mackenzie corridor,...
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Climate has warmed substantially in interior Alaska and several remote sensing studies have documented a decadal-scale decline in the normalized difference vegetation index (NDVI) termed a ‘browning trend’. Reduced summer soil moisture due to changing climatic factors such as earlier springs, less snowpack, and summer drought may reduce boreal productivity and NDVI. However, the relative importance of these climatic factors is poorly understood in boreal interior Alaska. In this study, I used the remotely sensed peak summer NDVI as an index of boreal productivity at 250 m pixel size from 2000 to 2014. Maximum summer NDVI was related to last day of spring snow, early spring snow water equivalent (SWE), and a...
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Discontinuous permafrost in the North American boreal forest is strongly influenced by the effects of ecological succession on the accumulation of surface organic matter, making permafrost vulnerable to degradation resulting from fire disturbance. To assess factors affecting permafrost degradation after wildfire, we compared vegetation composition and soil properties between recently burned and unburned sites across three soil landscapes (rocky uplands, silty uplands, and sandy lowlands) situated within the Yukon Flats and Yukon-Tanana Uplands in interior Alaska. Mean annual air temperatures at our study sites from 2011 to 2012 were relatively cold (-5.5 degrees C) and favorable to permafrost formation. Burning...
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Issue Title: Special issue: "Holocene paleoenvironmental records from Arctic lake sediment" Wetlands and lakes in the Tanana Valley, Alaska, have provided important resources for prehistoric humans who inhabited this region. We examine an ~11,200 cal yr BP record of environmental and paleolimnological changes from Quartz Lake in the middle Tanana Valley. Our data are also presented in the context of recent archaeological findings in the lake's general vicinity that have 18 associated AMS ^sup 14^C dates. We analyzed the stable-carbon and nitrogen isotope composition of total organic matter from the core, coupled with oxygen and carbon isotope analyses of Pisidiidae shells (fingernail clams), in addition to chironomid...
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Uncertainty in hydrometric data is a fact of life. Basic assumptions about the nature of this uncertainty are necessary in every analysis of hydrometric data, and an understanding of the variability of uncertainty can facilitate the effective use of hydrologic information. For most of the twentieth century there has been little change in hydrometric methods and many analysts explicitly or implicitly assume that the uncertainty has not changed over the period of record. We argue that there is substantial variability in the magnitude of uncertainty in published streamflow records that is not transparent to data users. Quantifying uncertainty is particularly important in the context of the current changes in hydrometric...
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GIS Metadata notes for AMJV Bird Habitat Conservation Areas (BHCA)Kirsten Luke GIS Specialist, Atlantic Coast Joint VentureCreated October 18, 2007Updated December 28, 2007Updated March 20, 2008Base data:a) Meeting Maps and excel spreadsheets from the Appalachian Mountains Joint Venture Technical Committee Meeting August 7- 9th 2007 b) National Land Cover Database (NLCD) 2001c) ESRI Street Map d) Federal Land : National Atlas Federal Lands Layer (2004) - these I believe are proclamation boundaries not actual fed land ownership boundariese) Protected Areas: Conservation Biology Institute Protected Areas Database (CBI -PAD) version 4. Land ownership boundaries - not proclamation boundaries.f) Audubon IBA's (2007)BHCA...
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In this study carbon dioxide and methane fluxes were measured in three dominant vegetational communities in a taiga peatland located within the zone of discontinuous permafrost in the Alaskan interior. Trace gas (CO2 and CH4 ) flux measurements were made across spatial scales from excised roots to in situ peatland ecosystems. Temperatures increases and local water tables decreases from 1991 to 1993 affected methane emission two sites. Mid season methane emissions in the tussock meadow was fairly constant, ranging from 56.3 ± 29.8 mg CH4 /m2 /day in 1991 to 62.3 ± 37.2 mg CH 4 /m2 /day in 1993. Emissions dropped in the drier dwarf spruce scrub from 12.2 ± 8.1 mg CH4 /m2 /day in 1991 to zero in 1993. In the floating...
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The social, cultural and economic value of barren-ground caribou to residents of the Northwest Territories (NWT) is immense. These migratory herds are hunted by Dene, Inuvialuit, Metis and non-aboriginal people from almost all communities on mainland Northwest Territories (NWT). The minimum annual harvest is 11,000 caribou with a minimum economic value of $17 million dollars (includes meat replacement and outfitting). Over the last ten years, the barren-ground caribou herds in the Northwest Territories (NWT) have declined from 40 to 86 percent. Management actions are required to assist declining caribou herds to recover and address the economic hardships resulting from low caribou numbers. The NWT Barren-ground...
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During the past ~50 years, the number and area of lakes have declined in several regions in boreal forests. However, there has been substantial finer-scale heterogeneity; some lakes decreased in area, some showed no trend, and others increased. The objective of this study was to identify the primary mechanisms underlying heterogeneous trends in closed-basin lake area. Eight lake characteristics (d18O, electrical conductivity, surface : volume index, bank slope, floating mat width, peat depth, thaw depth at shoreline, and thaw depth at the forest boundary) were compared for 15 lake pairs in Alaskan boreal forest where one lake had decreased in area since ~ 1950, and the other had not. Mean differences in characteristics...
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Koyukon Elders of Alaska's Interior observe that "cold weather is growing old" and recent warming is contributing to a world out of balance. Alaska is among the most rapidly warming places globally, with the Interior experiencing the most pronounced warming statewide, and with significant regional-scale ecosystem services disruptions affecting subsistence hunting and harvest success. Vulnerability of individuals, households, and communities to climate change is exacerbated by rising energy costs and a regulatory system that constrains the adaptive flexibility needed to cope with impacts on livelihoods. Socioeconomic and cultural change notwithstanding, the well-being of rural native communities is still dependant...
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Whitefish species in Alaska are subject to intensive subsistence fisheries everywhere they occur, commercial fisheries in certain places, and limited sport fisheries. Our understanding of whitefish biology comes primarily from studies of the same or similar species in other places, although some biological studies have taken place locally. Whitefish fisheries in the Yukon and Kuskokwim River drainages in Alaska have been documented in numerous anthropological and social science publications and in subsistence harvest surveys, but usually without species distinctions. Scientific sampling work since the 1960s has been reasonably effective at describing the species that are present and their distributions within the...
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Executive Summary: ... In response to criticisms of the northern regulatory regimes, in particular that of the Northwest Territories, and to calls for change, Indian and Northern Affairs Canada (INAC) developed the Northern Regulatory Improvement Initiative. The Northern Regulatory Improvement Initiative has a two-fold approach, focussing on both concrete, operational-level improvements to areas of federal responsibility, while building a longer-term regulatory improvement agenda. The longer-term approach included a detailed examination of the current regulatory systems for non-renewable resources in Northern Canada and a process to make improvements. This report is in response to the Cabinet Directive and the Northern...
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Introduction Improving vehicle trafficability planning is a major defense mission, and we believe that this research has made significant improvements towards this end. We are striving to develop new space-borne Synthetic Aperture Radar (SAR) techniques to measure temporal changes in soil moisture, soil freeze/thaw state, and snowmelt, utilizing both amplitude and phase signal information. Such knowledge is of great use to a variety of end-users. Military planners need to predict the bearing strength of the underlying soil and thus the number and weight of vehicles able to travel across it. Global climate modelers need to know the surface greenhouse gas and latent heat flux. The common variables in these applications...
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In 2002-03, the U.S. Geological Survey collected samples of streambed sediment at 18 sites in the lower Chena River watershed for analysis of selected nutrients, traces elements, and organic compounds. The purpose of the project was to provide Federal, State, and local agencies as well as neighborhood committees, with information for consideration in plans to improve environmental conditions in the watershed. The exploratory sampling program included analysis of streambed sediment from the Chena River and Chena Slough, a tributary to the Chena River. Results were compared to streambed-sediment guidelines for the protection of aquatic life and to 2001-02 sediment data from Noyes Slough, a side channel of the lower...
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PURPOSE: The deployment of a national missile defense (NMD) program in Alaska, California, Massachusetts, and North Dakota is considered. The NMD system would be a fixed, land-based, non-nuclear missile defense system with a land- and space-based detection system capable of responding to limited strategic ballistic missile threats to the United States. The proposed Alaskan sites include Clear Air Force Station (AFS) in Denali Borough, Eareckson Air Station (AS) on Shemya Island, Eielson Air Force Base (AFB) in Fairbanks North Star Borough, Fort Greely, and Yukon Training Area in Fairbanks North Star Borough. The proposed California site is Beale AFB. The proposed Massachusetts site is Cape Cod AFS. The proposed...
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The Greater Sage Grouse Focal Area represents an area of interest pertaining to the greater sage grouse under the U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) Working Lands for Wildlife (WLFW) Wildlife Habitat Incentive Program (WHIP).Working Lands for Wildlife is a partnership between NRCS and the U.S. Fish and Wildlife Service (FWS) to use agency technical expertise and financial assistance from the Wildlife Habitat Incentive Program to combat the decline of seven specific wildlife species whose decline can be reversed and will benefit other species with similar habitat needs. The WLFW project will target species whose decline can be reversed and will benefit other species...
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The Gopher Tortoise Focal Area represents an area of interest pertaining to the gopher tortoise under the U.S. Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS) Working Lands for Wildlife (WLFW) Wildlife Habitat Incentive Program (WHIP).Working Lands for Wildlife is a partnership between NRCS and the U.S. Fish and Wildlife Service (FWS) to use agency technical expertise and financial assistance from the Wildlife Habitat Incentive Program to combat the decline of seven specific wildlife species whose decline can be reversed and will benefit other species with similar habitat needs. The WLFW project will target species whose decline can be reversed and will benefit other species with...


map background search result map search result map Gopher Tortoise Focal Area (WLFW) Greater Sage Grouse Focal Area (WLFW) Ohio - AMJV Bird Habitat Conservation Areas Seasons out of balance: Climate change impacts, vulnerability, and sustainable adaptation in interior Alaska Quantifying Uncertainty in Streamflow Records A revised lithostratigraphic database of baseline geoscience information derived from seismic shothole drillers' logs, Northwest Territories and northern Yukon Edaphic and microclimatic controls over permafrost response to fire in interior Alaska Carbon cycle dynamics in a taiga peatland An ~11,200 year paleolimnological perspective for emerging archaeological findings at Quartz Lake, Alaska Occurrence of Selected Nutrients, Trace Elements, and Organic Compounds in Streambed Sediment in the Lower Chena River Watershed near Fairbanks, Alaska, 2002-03 Remote sensing of interannual boreal forest NDVI in relation to climatic conditions in interior Alaska Road to improvement: 'The review of the regulatory systems across the North' Whitefish Biology, Distribution, and Fisheries in the Yukon and Kuskokwim River Drainages in Alaska: a Synthesis of Available Information Determining the Utility of Synthetic Aperture Radar (SAR) in Estimating Surface Soil Moisture Conditions for Trafficability Analyses; Phase III Progress Report 2005 CHINOOK SALMON SONAR ENUMERATION ON THE BIG SALMON RIVER CRE-41-05. Prepared For: The Yukon River Panel Restoration and Enhancement Fund NATIONAL MISSILE DEFENSE DEPLOYMENT; FORT GREELY, SHEMYA ISLAND, AND DENALI AND FAIRBANKS NORTH STAR BOROUGHS, ALASKA, CALIFORNIA, MASSACHUSETTS, AND CAVALIER, GRAND FORKS, PEMBINA, RAMSEY, AND WALSH COUNTIES, NORTH DAKOTA Caribou Forever - Our Heritage, Our Responsiblity: A Barren-ground Caribou Management Strategy for the Northwest Territories 2006-2010 Mechanisms influencing changes in lake area in Alaskan boreal forest River piracy and drainage basin reorganization led by climate-driven glacier retreat An ~11,200 year paleolimnological perspective for emerging archaeological findings at Quartz Lake, Alaska 2005 CHINOOK SALMON SONAR ENUMERATION ON THE BIG SALMON RIVER CRE-41-05. Prepared For: The Yukon River Panel Restoration and Enhancement Fund Carbon cycle dynamics in a taiga peatland Determining the Utility of Synthetic Aperture Radar (SAR) in Estimating Surface Soil Moisture Conditions for Trafficability Analyses; Phase III Progress Report Ohio - AMJV Bird Habitat Conservation Areas Edaphic and microclimatic controls over permafrost response to fire in interior Alaska Seasons out of balance: Climate change impacts, vulnerability, and sustainable adaptation in interior Alaska Mechanisms influencing changes in lake area in Alaskan boreal forest Gopher Tortoise Focal Area (WLFW) Remote sensing of interannual boreal forest NDVI in relation to climatic conditions in interior Alaska A revised lithostratigraphic database of baseline geoscience information derived from seismic shothole drillers' logs, Northwest Territories and northern Yukon Greater Sage Grouse Focal Area (WLFW) Whitefish Biology, Distribution, and Fisheries in the Yukon and Kuskokwim River Drainages in Alaska: a Synthesis of Available Information River piracy and drainage basin reorganization led by climate-driven glacier retreat Caribou Forever - Our Heritage, Our Responsiblity: A Barren-ground Caribou Management Strategy for the Northwest Territories 2006-2010 Road to improvement: 'The review of the regulatory systems across the North' NATIONAL MISSILE DEFENSE DEPLOYMENT; FORT GREELY, SHEMYA ISLAND, AND DENALI AND FAIRBANKS NORTH STAR BOROUGHS, ALASKA, CALIFORNIA, MASSACHUSETTS, AND CAVALIER, GRAND FORKS, PEMBINA, RAMSEY, AND WALSH COUNTIES, NORTH DAKOTA