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Experiments have been conducted with a regional climate model to indicate the conditions required to generate preferred regions of frontal activity in the Alaskan region. Several objective methods of frontal identification were first investigated. It was found that· the vertical component of relative vorticity,· a thermal front parameter -&nablaB;|&nablaB;Tsub 850] | · n, where Tsub 850] is the 850-hPa temperature and n is a unit vector in the direction of the 850-hPa temperature gradient, and· a parameter derived from the Q vector as a measure of vertical motionwere useful in combination to determine the occurrence of fronts. The preferred locations for frontal activity were located to the southern side of the...
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A selective review of lichenometry as used to date Holocenemoraines in five diverse regions of Alaska and in southeastern Kamchatka suggests that growth curves for this North Pacific areamay be improved by attention to several factors. These includedlichen identification, control point number and distribution,radiocarbon calibration, alternative curve models, andcompatibility of lichen growth rate with climate. Support forcontrol points presented for Kamchatka and published for Alaska areas will benefit from supplementary control at and beyond thebreak from the great growth curve segments of the last centuries.With regard to alternative-linear, logarithmic, and compositecurve-models drawn for the published lichenometric...
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Recent studies have shown that ice duration in lakes and rivers over the Northern Hemisphere has decreased over the 19th and 20th centuries in response to global warming. However, lake ice trends have not been well documented in Canada. Because of its size, considerable variability may exist in both freeze-up and break-up dates across the country. In this paper, results of the analysis of recent trends (1951-2000) in freeze-up and break-up dates across Canada are presented. Trends toward earlier break-up dates are observed for most lakes during the time periods of analysis which encompass the 1990s. Freeze-up dates, on the other hand, show few significant trends and a low degree of temporal coherence when compared...
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Predictions of future fire activity over Canada's boreal forests have primarily been generated from climate data following assumptions that direct effects of weather will stand alone in contributing to changes in burning. However, this assumption needs explicit testing. First, areas recently burned can be less likely to burn again in the near term, and this endogenous regulation suggests the potential for self-limiting, negative biotic feedback to regional climate-driven increases in fire. Second, forest harvest is ongoing, and resulting changes in vegetation structure have been shown to affect fire activity. Consequently, we tested the assumption that fire activity will be driven by changes in fire weather without...
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Boreal regions contain more than half of the carbon in forested regions of the world and over 60% of the world's surface freshwater. Carbon storage and the flood control and water filtration provided by freshwaters and wetlands have recently been identified as the most important ecosystem services provided by boreal regions, with a value many times greater than current resource exploitation. Ecosystem services and sensitive ways of detecting their impairment have so far not been fully included in boreal conservation planning. Climate warming, via its effect on permafrost melting, insect damage, and forest fire, threatens to trigger large positive carbon feedbacks that may enhance the concentrations of greenhouse...
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Before the year 2001 there was no comprehensive hydrological dataset for the Yukon River Basin. Between 2000-2005 the USGS conducted the first comprehensive examination of water quality in the Yukon Basin. The YRITWC worked directly with the USGS to streamline the USGS study and protocol, to make a smooth transition to a YRITWC led study, using a Community Participatory Approach, at the end of the 5 year USGS study. In 2006 the ADEC conducted a two week field campaign examining the baseline biogeochemisty of the Tanana River. The partnership between the ADEC, YRITWC, USGS and USFWS was a direct result of the USGS and YRITWC's partnership and previous work of ADEC in the basin. Results from the nine years of...
map background search result map search result map Land cover disturbances and feedbacks to the climate system in Canada and Alaska Area management report for the recreational fisheries of Anchorage, 2003 Upper Cook Inlet commercial herring and smelt fisheries, 2004 Integrated landscape management in Canada: getting from here to there Preface - Hydrology of ice-covered rivers and lakes: scoping the subject McLean Lake area development scheme: draft final report Germanium/silicon ratios in the Copper River basin, Alaska: weathering and partitioning in periglacial versus glacial environments Marine Invasive Species and Biodiversity of South Central Alaska Exploring ecological changes in Cook Inlet beluga whale habitat though traditional and local ecological knowledge of contributing factors for population decline Denali National Park and Preserve Landcover Mapping Project Volume 2: Landcover classes and plant associations Yukon River Synoptic Survey Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation Rapid changes in the level of Kluane Lake in Yukon Territory over the last millennium Recent trends in Canadian lake ice cover Effects of biotic feedback and harvest management on boreal forest fire activity under climate change The Alaskan Arctic Frontal Zone: Forcing by Orography, Coastal Contrast, and the Boreal Forest Guidelines for Considering Traditional Knowledges in Climate Change Initiatives Impacts of Climate Warming on River Ice Break-up and Snowmelt Freshet Processes on the Porcupine River in Northern Yukon Recent trends in Canadian lake ice cover Germanium/silicon ratios in the Copper River basin, Alaska: weathering and partitioning in periglacial versus glacial environments Area management report for the recreational fisheries of Anchorage, 2003 Impacts of Climate Warming on River Ice Break-up and Snowmelt Freshet Processes on the Porcupine River in Northern Yukon McLean Lake area development scheme: draft final report Marine Invasive Species and Biodiversity of South Central Alaska Rapid changes in the level of Kluane Lake in Yukon Territory over the last millennium Denali National Park and Preserve Landcover Mapping Project Volume 2: Landcover classes and plant associations Upper Cook Inlet commercial herring and smelt fisheries, 2004 Exploring ecological changes in Cook Inlet beluga whale habitat though traditional and local ecological knowledge of contributing factors for population decline Yukon River Synoptic Survey Preface - Hydrology of ice-covered rivers and lakes: scoping the subject The Alaskan Arctic Frontal Zone: Forcing by Orography, Coastal Contrast, and the Boreal Forest Integrated landscape management in Canada: getting from here to there Land cover disturbances and feedbacks to the climate system in Canada and Alaska Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation Guidelines for Considering Traditional Knowledges in Climate Change Initiatives Effects of biotic feedback and harvest management on boreal forest fire activity under climate change