Skip to main content
Advanced Search

Filters: Tags: Monitoring 3-Improve Permafrost Mapping (X)

340 results (12ms)   

View Results as: JSON ATOM CSV
With increasing development of resources and transportation systems in areas of permafrost in Canada, the need for efficient and effective landslide hazard assessment in northern regions is greater now than ever. Furthermore, most climatological models suggest an accelerating warming trend for the region, along with more extreme climatic events, which would lead to increased landslide frequency. This project was undertaken to identify and characterize landslide processes in an area of discontinuous permafrost and to develop methods of landslide susceptibility mapping. The project includes 1:50 000 scale terrain evaluation mapping, detailed field-based landslide characterization, landslide inventory mapping, and...
thumbnail
A combination of binary logistic regression (BLR) and remote sensing techniques was used to generate a high-resolution spatially continuous near-surface (< 1.6 m) permafrost map. The BLR model was used to establish the relationship between vegetation type, aspect-slope, and permafrost presence; it predicted permafrost presence with an accuracy of 88%. Near-surface permafrost occupies 45% of the total vegetated area and 37% of the total study area. As less than 50% of the study area is underlain by near-surface permafrost, this distribution is characterized as "sporadic" for the study area.; A combination of binary logistic regression (BLR) and remote sensing techniques was used to generate a high-resolution spatially...
thumbnail
The Arctic is in transition from climate-driven thawing of permafrost. We investigate satellite-derived water equivalent mass changes, snow water equivalent with in situ measurements of runoff and ground-survey derived geoid models from 1999 through 2009. The Alaskan Arctic coastal plain groundwater storage (including wetland bog, thaw pond and lake) is increasing by 1.15 ± 0.65 km3/a (area-average 1.10 ± 0.62 cm/a), and Yukon River watershed groundwater storage is decreasing by 7.44 ± 3.76 km3/a (area‑average 0.79 ± 0.40 cm/a). Geoid changes show increases within the Arctic coastal region and decreases within the Yukon River watershed. We hypothesize these changes are linked to the development of new predominately...
thumbnail
Increased attention directed at the permafrost region has been prompted by resource development and climate change. This review surveys advances in permafrost hydrology since 2000. Data shortage and data quality remain serious concerns. Yet, there has been much progress in understanding fundamental hydrologic processes operating in a wide range of environments, from steep mountainous catchments, to the Precambrian Shield with moderate relief, to the low-gradient terrain of plains, plateaus and wetlands. Much of the recent research has focused on surface water, although springs and groundwater contribution to streamflow have also been studied. A compendium of water-balance research from 39 high-latitude catchments...
thumbnail
Accurate representations of subsurface flow in hydrologic models of permafrost terrain during spring thaw require an understanding of soil thaw and soil thaw rates. Field data, including daily photographs for snowcover estimation and meteorological measurements, and measurements of soil thaw depth, soil temperature and soil moisture content, were acquired on an organic-covered hillslope in Granger Basin, Yukon Territory, to quantify relationships between net radiation and soil thaw energy. The infiltration and freezing of meltwater into the soil likely contributes to pre-thaw warming. When this energy (1.82 MJ m super(-2)d super(-1)) is taken into consideration, the daily mean contribution to soil thaw from net...
thumbnail
The impact to the permafrost during and after wildfire was studied using 11 boreal forest fire sites including two controlled burns. Heat transfer by conduction to the permafrost was not significant during fire. Immediately following fire, ground thermal conductivity may increase 10-fold and the surface albedo can decrease by 50% depending on the extent of burning of the surficial organic soil. The thickness of the remaining organic layer strongly affects permafrost degradation and aggradation. If the organic layer thickness was not reduced during the burn, then the active layer (the layer of soil above permafrost that annually freezes and thaws) did not change after the burn in spite of the surface albedo decrease....
thumbnail
Thawing and freezing processes are key components in permafrost dynamics, and these processes play an important role in regulating the hydrological and carbon cycles in the northern high latitudes. In the present study, we apply a well-developed soil thermal model that fully couples heat and water transport, to simulate the thawing and freezing processes at daily time steps across multiple sites that vary with vegetation cover, disturbance history, and climate. The model performance was evaluated by comparing modeled and measured soil temperatures at different depths. We use the model to explore the influence of climate, fire disturbance, and topography (north- and south-facing slopes) on soil thermal dynamics....
thumbnail
Groundwater discharge to rivers has increased in recent decades across the circumpolar region and has been attributed to thawing permafrost in arctic and subarctic watersheds. Permafrost-driven changes in groundwater discharge will alter the flux of dissolved organic carbon (DOC) in rivers, yet little is known about the chemical composition and reactivity of dissolved organic matter (DOM) of groundwater in permafrost settings. Here, we characterize DOM composition of winter flow in 60 rivers and streams of the Yukon River basin to evaluate the biogeochemical consequences of enhanced groundwater discharge associated with permafrost thaw. DOC concentration of winter flow averaged 3.9 ± 0.5 mgCL-1, yet was highly variable...
INTRODUCTION This report briefly describes and presents geochemical and biogeochemical data for a cooperative study in the Fortymile Mining District, east central Alaska. This study is being funded by the U.S. Geological Survey (USGS) Mineral Resources Program through Fiscal Year 2001. Cooperative funds are being provided from various State of Alaska sources through the Alaska Department of Natural Resources. Results for the first field season completed in June 1997 are presented in Crock and others (1999). The study's second field season was completed in June 1998 and the results of the sample analyses for this phase of the study are presented here. Primary objectives of this study are: * Determine the regional...
Carbon release from thawing permafrost soils could significantly exacerbate global warming as the active-layer deepens, exposing more carbon to decay. Plant community and soil properties provide a major control on this by influencing the maximum depth of thaw each summer (active-layer thickness; ALT), but a quantitative understanding of the relative importance of plant and soil characteristics, and their interactions in determine ALTs, is currently lacking. To address this, we undertook an extensive survey of multiple vegetation and edaphic characteristics and ALTs across multiple plots in four field sites within boreal forest in the discontinuous permafrost zone (NWT, Canada). Our sites included mature black spruce,...
thumbnail
This study is the first known attempt in North America to use the basal temperature of snow (BTS) method to predict the distribution of mountain permafrost. The study site, Wolf Creek Research Basin, Yukon Territory (60°30'N, 135°13'W), is a 195 km 2 basin ranging in elevation from 650-2100 m with a mean annual air temperature of about -4°C at 1235 m a.s.l. A modeled BTS surface, based on 394 measured BTS values and with elevation and potential incoming solar radiation as independent variables, was created within a GIS environment with an r2 value similar to European results. The distribution of permafrost within the basin was identified from pits and boreholes. A subsequent logistic regression was used to compare...
thumbnail
The Bonanza Creek Experimental Forest (BCEF) is a 5053 ha research area located approximately 20 km southwest of Fairbanks, AK along the Parks Highway. The Forest is within the Tanana Valley State Forest, a unit managed by the Division of Forestry, State of Alaska. The area represents a transect of typical vegetation and landforms in interior Alaska, and includes a section of the Tanana River floodplain at an elevation of approximately 120 m and adjacent uplands. These uplands form the southern limit of the Tanana-Yukon uplands, rising to a ridge crest of 470 m. The vegetation, a mosaic of forest and non-forest types, corresponds to four broad topographic zones: upland hills and ridges, lowland toeslopes and valley...
map background search result map search result map Progress in permafrost hydrology in the new millennium Fine root biomass in two black spruce stands in interior Alaska: effects of different permafrost conditions Impacts of wildfire on the permafrost in the boreal forests of Interior Alaska Resilience and vulnerability of permafrost to climate change Evaluation of the basal temperature of snow (BTS) method to map permafrost in complex mountainous terrain, Wolf Creek, Yukon Territory Dissolved organic matter composition of winter flow in the Yukon River basin: Implications of permafrost thaw and increased groundwater discharge Modeling thermal dynamics of active layer soils and near-surface permafrost using a fully coupled water and heat transport model Effects of wildfire and permafrost on soil organic matter and soil climate in interior Alaska Distinct Fluvial Patterns of a Headwater Stream Network Underlain by Discontinuous Permafrost Apparent recent trends in hydrologic response in permafrost regions of northwest Canada Alaskan Permafrost Groundwater Storage Changes Derived from GRACE and Ground Measurements Scale-dependent environmental controls over species composition in Alaskan black spruce communities Near-Surface Permafrost Distribution Mapping Using Logistic Regression and Remote Sensing in Interior Alaska Estimating soil thaw energy in sub-Alpine tundra at the hillslope scale, wolf creek, Yukon Territory, Canada Bonanza Creek Long Term Ecological Research Consortium for Permafrost Ecosystems in Transition: Traversing the Southern Margin of Discontinuous Permafrost with Hydrological, Ecological and Remote Sensing Research, Northeastern British Columbia and Southwestern Northwest Territories Distinct Fluvial Patterns of a Headwater Stream Network Underlain by Discontinuous Permafrost Fine root biomass in two black spruce stands in interior Alaska: effects of different permafrost conditions Estimating soil thaw energy in sub-Alpine tundra at the hillslope scale, wolf creek, Yukon Territory, Canada Evaluation of the basal temperature of snow (BTS) method to map permafrost in complex mountainous terrain, Wolf Creek, Yukon Territory Effects of wildfire and permafrost on soil organic matter and soil climate in interior Alaska Bonanza Creek Long Term Ecological Research Near-Surface Permafrost Distribution Mapping Using Logistic Regression and Remote Sensing in Interior Alaska Scale-dependent environmental controls over species composition in Alaskan black spruce communities Impacts of wildfire on the permafrost in the boreal forests of Interior Alaska Consortium for Permafrost Ecosystems in Transition: Traversing the Southern Margin of Discontinuous Permafrost with Hydrological, Ecological and Remote Sensing Research, Northeastern British Columbia and Southwestern Northwest Territories Resilience and vulnerability of permafrost to climate change Progress in permafrost hydrology in the new millennium Modeling thermal dynamics of active layer soils and near-surface permafrost using a fully coupled water and heat transport model Apparent recent trends in hydrologic response in permafrost regions of northwest Canada Dissolved organic matter composition of winter flow in the Yukon River basin: Implications of permafrost thaw and increased groundwater discharge Alaskan Permafrost Groundwater Storage Changes Derived from GRACE and Ground Measurements