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USGS is the nation's premiere earth and natural science research organization. Because our core mission is to provide objective science and technical support to address a wide array of important societal issues, our capabilities and activities are diverse. Our work is conducted by employees at our Science Centers, and in collaboration with our many external partners.
HVO operates monitoring networks, assesses hazards, and issues notifications of volcanic activity and earthquakes in the State of Hawai‘i. HVO scientists conduct fundamental research on volcanic processes and work to educate the communities at risk. HVO is located in Hawaiʻi Volcanoes National Park on the Island of Hawaii.
Climate scenarios for California
Possible future climate changes in California are investigated from a varied set of climate change model simulations. These simulations, conducted by three state-of-the-art global climate models, provide trajectories from three greenhouse gas (GHG) emission scenarios. These scenarios and the resulting climate simulations are not “predictions...Cayan, Daniel R.; Maurer, Ed; Dettinger, Mike; Tyree, Mary; Hayhoe, Katharine; Bonfils, Celine; Duffy, Phil; Santer, Ben
Projecting future sea level
California’s coastal observations and global model projections indicate that California’s open coast and estuaries will experience increasing sea levels over the next century. Sea level rise has affected much of the coast of California, including the Southern California coast, the Central California open coast, and the San Francisco...Cayan, Daniel R.; Bromirski, Peter; Hayhoe, Katharine; Tyree, Mary; Dettinger, Mike; Flick, Reinhard
Summary of Suspended-Sediment Concentration Data, San Francisco Bay, California, Water Year 2004Buchanan, Paul A.; Lionberger, Megan A.
Sediment deposition and erosion in south San Francisco Bay, California from 1956 to 2005
Sediment deposition and erosion in South San Francisco Bay from 1956 to 2005 was studied by comparing bathymetric surveys made in 1956, 1983, and 2005. From 1956 to 1983, the region was erosional. In contrast, from 1983 to 2005, the region was depositional. Analysis of subregions defined by depth, morphology and location revealed similarities in...Jaffe, Bruce; Foxgrover, Amy C.
A history of intertidal flat area in south San Francisco Bay, California: 1858 to 2005
A key question in salt pond restoration in South San Francisco Bay is whether sediment sinks created by opening ponds will result in the loss of intertidal flats. Analyses of a series of bathymetric surveys of South San Francisco Bay made from 1858 to 2005 reveal changes in intertidal flat area in both space and time that can be used to better...Jaffe, Bruce; Foxgrover, Amy C.
Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto regional water quality control plant in south San Francisco Bay, California: 2005
Trace elements in sediment and the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton 1995), clam reproductive activity and benthic, macroinvertebrate community structure are reported for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay. This...Cain, Daniel J.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Lorenzi, Allison H.; Moon, Edward; Shouse, Michelle K.; Hornberger, Michelle I.; Dyke, Jessica
A tool for assessing mercury loadings from restored tidal systems
Accurately quantifying net loads in tidal systems is difficult owing to the high variability in constituent concentrations over the vastly different time scales present in these systems. Perhaps most difficult is the measurement of fluxed over the tidal time scale. On this scale, the net export of the constituent is orders of magnitude less than...Fleck, J.A.; Bergamaschi, B.A.; Downing, B.D.; Lionberger, M.A.; Schoellhamer, D.H.; Boss, E.; Stephenson, M.
Sediment supply and demand for salt pond restorationTrulio, Lynne; Schoellhamer, David H.; Orlando, James L.; Wright, Scott A.; Freeman, Larry A.
Eutrophication of freshwater and marine ecosystems
Initial understanding of the links between nutrients and aquatic productivity originated in Europe in the early 1900s, and our knowledge base has expanded greatly during the past 40 yr. This explosion of eutrophication-related research has made it unequivocally clear that a comprehensive strategy to prevent excessive amounts of nitrogen and...Smith, Val H.; Joye, Samantha B.; Howarth, Robert W.
A component-resampling approach for estimating probability distributions from small forecast ensembles
In many meteorological and climatological modeling applications, the availability of ensembles of predictions containing very large numbers of members would substantially ease statistical analyses and validations. This study describes and demonstrates an objective approach for generating large ensembles of "additional" realizations from smaller...Dettinger, M.
Degradation of water quality by bird feces in and around managed wetlands
No abstract available.Shellenbarger, G.G.; Boehm, A.B.
Ecological values of shallow-water habitats: Implications for the restoration of disturbed ecosystems
A presumed value of shallow-habitat enhanced pelagic productivity derives from the principle that in nutrient-rich aquatic systems phytoplankton growth rate is controlled by light availability, which varies inversely with habitat depth. We measured a set of biological indicators across the gradient of habitat depth within the Sacramento–San...Lopez, C.B.; Cloern, J.E.; Schraga, T.S.; Little, A.J.; Lucas, L.V.; Thompson, J.K.; Burau, J.R.
“Variance” image produced from video shot at Cowells Beach in Santa Cruz, California, on May 6, 2017. The more the light intensity changes at a given spot, or “pixel,” during the video, the brighter the value assigned to that pixel. Motion tends to produce changes in light intensity. Note bright areas along and beyond the shore where waves were breaking. Researchers are...
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost. Now,...
Installing large boulders as rip rap to armor the shore against further erosion at Goleta Beach in Southern California. The tide is very low (negative).
USGS staff gage (ruler) measuring the height of the water, on the Carson River, near Brunswick Canyon, Nevada.
A sonar-equipped personal watercraft mapping the bathymetry underwater near Santa Cruz, Calif.
Research and technical support provided by USGS makes a difference Some recent press releases and media advisories from the Pacific Region are highlighted below.
Water users around the country can now view the past and simulated future of hydrologic processes.
On January 13, scientists from the U.S. Geological Survey will be working on the beach in Santa Cruz at the mouth of the San Lorenzo River. Using a sonar-equipped boat and personal watercraft, they will be surveying the beach and the nearby ocean bottom to compile a three-dimensional map of how the beach changed during storms that struck this week.
The U.S. Geological Survey’s California Water Science Center is hosting a media event Wednesday, Jan. 11 at a USGS streamgage location about 7 miles north of Santa Cruz, California. A hydrologist will be available for interviews as field crews collect streamflow data.
The U.S. Geological Survey’s California Water Science Center is hosting a media event Monday, Jan. 9 at a USGS streamgage location below Friant Dam, a streamflow site with significance to the San Juan River Restoration Project.
Successfully resolving California’s long-standing water supply and ecosystem restoration conflicts in the Delta requires developing sound policy solutions based on data derived from the best available science.
Residents should not be alarmed to witness a low-flying helicopter over the eastern Mojave Desert starting around November 14.
Scientists, engineers and resource managers meet in Sacramento to explore the theme of “Science for Solutions: Linking Data and Decisions” at the 9th Biennial Bay-Delta Science Conference.
A new study from the USGS suggests that some early 20th century earthquakes in southern California might have been induced (man-made) by past practices that were used by the oil and gas industry.
U.S. Geological Survey scientists and their coauthors from the California Coastal Records Project have found a way to use historical aerial photographs not just to see evidence of coastal erosion, but to accurately measure how much has occurred over time.
A new study offers the most sophisticated analyses to date on how Los Angeles-area groundwater supplies are replenished. The analyses provide water managers with a clearer understanding of the sources and amount of available groundwater in the region – information that is important for planning and management of the vital resource.
At the request of the Bureau of Land Management, USGS has released an assessment of mineral resources in six Western states.
Roughly over a quarter of the golden eagles killed at the Altamont Pass Wind Resource Area in Northern California from 2012-2014 were recent immigrants to the local population, according to research led by the U.S. Geological Survey.
Nine USGS Science Centers are administered by the Pacific Regional office, which is headquartered in Sacramento, California.
The Pacific Region works with a wide array of partners across the country, including other Federal and state agencies, regional and local governments, academic institutions, research organizations, non-governmental organizations, and more.