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Disturbance related to fire or hydrologic processes can cause degradation of deep (greater than 1 m) permafrost. These changes in deep permafrost have the potential to impact landscapes and infrastructure, alter the routing and distribution of surface water or groundwater, and may contribute to the flux of carbon to terrestrial...

Permafrost is found throughout northern latitudes, and hasfar reaching implications for natural and man-made environments including hydrologic processes, landscape dynamics, ecosystems, and infrastructure. While maps of near-surface permafrost characteristics are available, relatively little is known about permafrost distributions at depth over large areas. Here, we summarize several frequency domain airborne...

The U.S. Geological Survey is partnering with the IberoAmerican Association of Geological and Mining Surveys (ASGMI) to conduct an assessment of undiscovered metallic and non-metallic resources in the Greater Antilles region. The assessment plans to provide science-based information on the geologic availability of these resources for development, land-use planning, and...

Currently, an aftershock sequence is ongoing in Alaska after the magnitude 7.0 Anchorage earthquake of November 30, 2018. Using two scenarios, determined with observations as of December 14, 2018, this report estimates that it will take between 2.5 years and 3 decades before the rate of aftershocks decays...

Understanding the relationship between environmental factors and vital rates is an important step in predicting a species’ response to environmental change. Species associated with sea ice are of particular concern because sea ice is projected to decrease rapidly in polar environments with continued levels of greenhouse gas emissions. The relationship...

We collected blood and serum from 155 brown bears (Ursus arctos) inhabiting five locations in Alaska during 2013–16 and tested samples for evidence of prior exposure to a suite of bacterial, viral, and parasitic agents. Antibody seroprevalence among Alaska brown bears was estimated to be 15% for Brucella spp., 10% for Francisella tularensis,...

Influenza A viruses (IAVs) are maintained in wild waterbirds and have the potential to infect a broad range of species, including wild mammals. The Arctic Coastal Plain of Alaska supports a diverse suite of species, including waterfowl that are common hosts of IAVs. Mammals co-occur with geese and other migratory...

The Farewell terrane is an exotic continental fragment in interior Alaska that during the early Paleozoic was the site of a passive margin. We report a 238U/206Pb zircon age of 432.9±3.0 Ma from a Farewell terrane ash in Mt. McKinley quadrangle, Alaska. This age overlaps with prominent detrital zircon age...

Data that have been processed to allow analysis with a minimum of additional user effort are often referred to as Analysis Ready Data (ARD). The ability...

The National Elevation Dataset (NED) is a primary elevation data product that has been produced and distributed by the U.S. Geological Survey (USGS). Since its inception, the USGS has compiled and published topographic information in many forms, and the NED is a significant development in this long line of products...

Understanding the diet of deep-diving predators can provide essential insight to the trophic structure of the mesopelagic ecosystem. Comprehensive population-level diet estimates are exceptionally difficult to obtain for elusive marine predators due to the logistical challenges involved in observing their feeding behavior and collecting samples for traditional stomach content or...

Disaster research often focuses on how and why communities are affected by a discrete extreme event. We used the community capitals framework to understand how community characteristics influence their preparedness, response to, and recovery from successive or multiple disasters using the 1964 Good Friday Earthquake and the...

Large carnivores are imperiled globally, and characteristics making them vulnerable to extinction (e.g., low densities and expansive ranges) also make it difficult to estimate demographic parameters needed for management. Here we develop an integrated population model to analyze capture-recapture, radiotelemetry, and count data for the Chukchi Sea subpopulation of polar...

Invasive species are a subset of non-native (or alien) species, and knowing what species are non-native to a region is a first step to managing invasive species. People have been compiling non-native and invasive species lists ever since these species started causing harm, yet national non-native species lists are neither...

1. The total flux of carbon—which includes gaseous emissions, lateral flux, and burial—from inland waters across the conterminous United States (CONUS) and Alaska is 193 teragrams of carbon (Tg C) per year. The dominant pathway for carbon movement out of inland waters is the emission of carbon dioxide gas across...

Climate change is expected to alter the composition, structure, and function of forested ecosystems in the United States (Vose et al. 2012). Increases in atmospheric concentrations of greenhouse gases (e.g., carbon dioxide [CO2]) and temperature, as well as altered precipitation and disturbance regimes (e.g., fire, insects, pathogens, and windstorms), are...

There are two components to this document. The first component is the scope of described environmental change and its impacts in Port Heiden Alaska. The second component is a list of priorities to be addressed that will help Port Heiden achieve its vision for the future. Each priority area incorporates...

Most of Hawaii's endemic avifauna are species of conservation concern. Some of Hawaii's endangered waterbirds, however, have increased in number as a result of intensive management of wetlands. To inform these conservation efforts, we examined interisland genetic structure and gene flow within 2 Hawaiian endemic waterbirds, the Hawaiian Coot (Fulica...

We report data for 112 apatite and 31 zircon fission track (AFT and ZFT) outcrop sandstone samples along a transect that spans the western Brooks Range. Sampling targeted structures that modify the Middle Jurassic‐Early Cretaceous early Brookian orogen. The AFT samples record latest Cretaceous to Eocene...

A methodology based on general hydraulic relations for rivers has been developed to estimate the discharge (flow rate) of rivers using satellite remote sensing observations. The estimates of discharge, flow depth, and flow velocity are derived from remotely observed water...

When erupting, all volcanoes pose a degree of risk to people and infrastructure, however, the risks are not equivalent from one volcano to another because of differences in eruptive style and geographic location. Assessing the relative threats posed by U.S. volcanoes identifies which volcanoes warrant the greatest risk-mitigation efforts by...

Trough ponds are ubiquitous features of Arctic landscapes and an important component of freshwater aquatic ecosystems. Permafrost thaw causes ground subsidence, creating depressions that gather water, creating ponds. Permafrost thaw also releases solutes and nutrients, which may fertilize these newly formed ponds. We measured water budget...

Purpose of ReviewI sought to review the contributions of recent literature and prior foundational papers to our understanding of drought and fire. In this review, I summarize recent literature on drought and fire in the western USA and discuss research directions that may increase the...

The paper summarizes an end-to-end activity connecting the global climate modeling enterprise with users of climate information in Alaska. The effort included retrieval of the requisite observational datasets and model output, a model evaluation and selection procedure, the actual downscaling by the delta method with its inherent bias-adjustment, and the provision of products to...

The satellite‐derived Normalized Difference Vegetation Index (NDVI) is commonly used by researchers and managers to represent ungulate forage conditions in landscapes across the globe, despite limited information about how it compares to empirical measurements of forage quality and quantity. The application of NDVI as a forage metric is particularly appealing...