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Publications

USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.

Filter Total Items: 2891

Summer habitat selection by Dall’s sheep in Wrangell-St. Elias National Park and Preserve, Alaska

Sexual segregation occurs frequently in sexually dimorphic species, and it may be influenced by differential habitat requirements between sexes or by social or evolutionary mechanisms that maintain separation of sexes regardless of habitat selection. Understanding the degree of sex-specific habitat specialization is important for management of wildlife populations and the design of monitoring and
Authors
Gretchen H. Roffler, Layne G. Adams, Mark Hebblewhite

Climate changes and wildfire alter vegetation of Yellowstone National Park, but forest cover persists

We present landscape simulation results contrasting effects of changing climates on forest vegetation and fire regimes in Yellowstone National Park, USA, by mid-21st century. We simulated potential changes to fire dynamics and forest characteristics under three future climate projections representing a range of potential future conditions using the FireBGCv2 model. Under the future climate scenari
Authors
Jason A. Clark, Rachel A. Loehman, Robert E. Keane

Modeling ancient land use and resilient forests in the Jemez Mountains

No abstract available.
Authors
Rachel A. Loehman

High-latitude dust in the Earth system

Natural dust is often associated with hot, subtropical deserts, but significant dust events have been reported from cold, high latitudes. This review synthesizes current understanding of high-latitude (≥50°N and ≥40°S) dust source geography and dynamics and provides a prospectus for future research on the topic. Although the fundamental processes controlling aeolian dust emissions in high latitude
Authors
Joanna E Bullard, Matthew Baddock, Tom Bradwell, John Crusius, Eleanor Darlington, Diego Gaiero, Santiago Gasso, Gudrun Gisladottir, Richard Hodgkins, Robert McCulloch, Cheryl NcKenna Neuman, Tom Mockford, Helena Stewart, Throstur Thorsteinsson

Hydrologic and geomorphic changes resulting from episodic glacial lake outburst floods: Rio Colonia, Patagonia, Chile

Glacial lake outburst floods (GLOFs) are a prominent but poorly understood cryospheric hazard in a warming climate. We quantify the hydrologic and geomorphic response to 21 episodic GLOFs that began in April 2008 using multitemporal satellite imagery and field observations. Peak discharge exiting the source lake became progressively muted downstream. At ~40–60 km downstream, where the floods enter
Authors
J. Jacquet, S.W. McCoy, Daniel Mcgrath, David Nimick, Mark Fahey, J. O'kuinghttons, B.A. Friesen, J. Leidich

Links between atmosphere, ocean, and cryosphere from two decades of microseism observations on the Antarctic Peninsula

The lack of landmasses, climatological low pressure, and strong circumpolar westerly winds between the latitudes of 50°S to 65°S produce exceptional storm‐driven wave conditions in the Southern Ocean. This combination makes the Antarctic Peninsula one of Earth's most notable regions of high‐amplitude wave activity and thus, ocean‐swell‐driven microseism noise in both the primary (direct wave‐coast
Authors
Robert E. Anthony, Richard C. Aster, Daniel Mcgrath

An empirical approach for estimating stress-coupling lengths for marine-terminating glaciers

Variability in the dynamic behavior of marine-terminating glaciers is poorly understood, despite an increase in the abundance and resolution of observations. When paired with ice thicknesses, surface velocities can be used to quantify the dynamic redistribution of stresses in response to environmental perturbations through computation of the glacier force balance. However, because the force balanc
Authors
Ellyn Enderlin, Gordon S. Hamilton, Shad O'Neel, Timothy C. Bartholomaus, Mathieu Morlighem, John W. Holt

Conservation status of polar bears (Ursus maritimus) in relation to projected sea-ice declines

Loss of Arctic sea ice owing to climate change is the primary threat to polar bears throughout their range. We evaluated the potential response of polar bears to sea-ice declines by (i) calculating generation length (GL) for the species, which determines the timeframe for conservation assessments; (ii) developing a standardized sea-ice metric representing important habitat; and (iii) using statist
Authors
Eric V. Regehr, Kristin L. Laidre, H. Resit Akçakaya, Steven C. Amstrup, Todd C. Atwood, Nicholas J. Lunn, Martyn E. Obbard, Harry Stern, Gregory W. Thiemann, Øystein Wiig

Interactions among vegetation, climate, and herbivory control greenhouse gas fluxes in a subarctic coastal wetland

High-latitude ecosystems are experiencing the most rapid climate changes globally, and in many areas these changes are concurrent with shifts in patterns of herbivory. Individually, climate and herbivory are known to influence biosphere-atmosphere greenhouse gas (GHG) exchange; however, the interactive effects of climate and herbivory in driving GHG fluxes have been poorly quantified, especially i
Authors
K.C. Kelsey, A.J. Leffler, K.H. Beard, Joel A. Schmutz, R.T. Choi, J.M. Welker

Multidecadal increases in the Yukon River Basin of chemical fluxes as indicators of changing flowpaths, groundwater, and permafrost

The Yukon River Basin, underlain by discontinuous permafrost, has experienced a warming climate over the last century that has altered air temperature, precipitation, and permafrost. We investigated a water chemistry database from 1982 to 2014 for the Yukon River and its major tributary, the Tanana River. Significant increases of Ca, Mg, and Na annual flux were found in both rivers. Additionally,
Authors
Ryan C. Toohey, Nicole M. Herman-Mercer, Paul F. Schuster, Edda A. Mutter, Joshua C. Koch

Haemosporidian parasite infections in grouse and ptarmigan: Prevalence and genetic diversity of blood parasites in resident Alaskan birds

Projections related to future climate warming indicate the potential for an increase in the distribution and prevalence of blood parasites in northern regions. However, baseline data are lacking for resident avian host species in Alaska. Grouse and ptarmigan occupy a diverse range of habitat types throughout the northern hemisphere and are among the most well-known and important native game birds
Authors
Matthew M. Smith, Caroline R. Van Hemert, Richard Merizon

Deciduous trees are a large and overlooked sink for snowmelt water in the boreal forest

The terrestrial water cycle contains large uncertainties that impact our understanding of water budgets and climate dynamics. Water storage is a key uncertainty in the boreal water budget, with tree water storage often ignored. The goal of this study is to quantify tree water content during the snowmelt and growing season periods for Alaskan and western Canadian boreal forests. Deciduous trees rea
Authors
Jessica Young, W. Robert Bolton, Uma Bhatt, Jordi Cristobal, Richard Thoman