Publications

The initial effects from an asteroid impact are generally well characterized and include thermal radiation and blast waves. If the impactor is sufficiently large, either an earthquake or tsunami can also result, depending on whether the impact occurs over land or water. However, the longer-term effects that extend beyond the area initially affected are less well characterized. Because...

A flexible spill program in the federal Columbia River power system increased the total dissolved gas (TDG) water quality standards (i.e., the gas cap) from 120% to 125%. Spill is used to pass juvenile salmon (Oncorhynchus spp.) over dams, but it can generate elevated TDG, and exposed fish can develop gas bubble trauma (GBT) or experience mortality. Juvenile salmon are monitored for GBT...

In Alaska’s watersheds, climate change is altering the nature and role of the snowpack, defined as snow accumulation that melts in spring. Generally, the amount of precipitation that falls as snow and the length of the snow-cover season both decrease as temperatures exceed 0°C (32°F) more frequently. The impacts of climate change on snowpack vary among watersheds. In southern, coastal...

Reliable estimates of the magnitude and frequency of floods are an important part of the framework for hydraulic-structure design and flood-plain management in Georgia, South Carolina, and North Carolina. Annual peak flows measured at U.S. Geological Survey streamgages are used to compute flood‑frequency estimates at those streamgages. However, flood‑frequency estimates also are needed...

Reliable flood-frequency estimates are important for hydraulic structure design and floodplain management in Georgia, South Carolina, and North Carolina. Annual peak streamflows (hereafter, referred to as peak flows) measured at 965 U.S. Geological Survey streamgages were used to compute flood-frequency estimates with annual exceedance probabilities (AEPs) of 50, 20, 10, 4, 2, 1, 0.5...

U.S. Geological Survey (USGS) research has supported management of Hypophthalmichthys nobilis (bighead carp), Mylopharyngodon piceus (black carp), Ctenopharyngodon idella (grass carp), and H. molitrix (silver carp), hereafter referred to collectively as invasive carps, for over a decade. This strategic framework identifies thematic research areas to guide funding decisions for USGS...

On 12 January 2020, an eruption began on the shores of the Main Crater Lake (MCL) of Taal Volcano—a caldera system on the southern end of Luzon Island in the Philippines. Taal, one of the most active volcanoes in the Philippines, is located 30 km south of Manila—a major metropolitan area with a population of 13.5 million people. Eruptive activity intensified throughout the day on 12...

Introduction The U.S. Geological Survey (USGS) serves a principal role in conducting wildlife disease outbreak investigations, surveillance, and ecological research to support management of diseases in free-ranging native wildlife. Approximately 60 percent of emerging human infectious diseases such as COVID-19, are zoonotic, meaning they are transmitted between animals and humans and 70...

This chapter explains the rationale for considering shallowly buried (0 to >5 m depth) water ice in the mid-latitudes of Mars as a resource to support future human missions, and describes a NASA-funded effort to map that ice with existing orbital remote-sensing data. In recent decades, numerous studies have used various datasets to investigate the presence and stability of water ice in...

The National Earthquake Hazards Reduction Program (NEHRP) Reauthorization Act of 2018 (Pub.L. 115–307) requires that the Federal Emergency Management Agency (FEMA) “shall support the implementation of a comprehensive earthquake education, outreach, and public awareness program, including development of materials and their wide dissemination to all appropriate audiences and support public...

Juvenile salmonids migrate hundreds of kilometers from their natal streams to mature in the ocean. Throughout this migration, they respond to environmental cues such as local water velocities and other stimuli to direct and modulate their movements, often through heavily modified riverine and estuarine habitats. Management strategies in an uncertain future of climate change and altered...

Because use of high-resolution hydrologic models is becoming more widespread and estimates are made over large domains, there is a pressing need for systematic evaluation of their performance. Most evaluation efforts to date have focused on smaller basins that have been relatively undisturbed by human activity, but there is also a need to benchmark model performance more comprehensively...