Unified Interior Regions

California

The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

States L2 Landing Page Tabs

Filter Total Items: 417
Date published: October 18, 2018
Status: Active

Aquifer Compaction due to Groundwater Pumping

Although land subsidence caused by groundwater pumping has caused many negative effects on human civil works for centuries, especially in the highly developed urban or industrialized areas of Europe, the relation between subsidence and groundwater pumpage was not understood or recognized for a long time. Recognition began in 1928 when pioneer researcher O.E. Meinzer of the U.S. Geological...

Contacts: Michelle Sneed
Date published: October 18, 2018
Status: Active

Genomic Mechanisms that Underlie Lack of Recovery of Prince William Sound Herring Following the 1990s Collapse

In the decades following the Exxon Valdez Oil Spill (EVOS), it has become increasingly apparent that oil can be toxic at extremely low concentrations to developing fish embryos including herring, where some toxic phenotypes may be apparent during embryogenesis, but some are delayed until later in life. Therefore, acute and lingering oil may act as an insidious selective force within...

Contacts: Paul Hershberger, Ph.D., Jacob Gregg, Ashley MacKenzie, William Richards, Andrew Whitehead, John Incardona, Nat Scholtz
Date published: October 17, 2018
Status: Active

Land Subsidence in the San Joaquin Valley

The San Joaquin Valley is one of the most productive agricultural regions in the nation. Beginning around the 1920's, farmers relied upon groundwater for water supply. Over time, overpumping caused groundwater-level declines and associated aquifer-system compaction and land subsidence that resulted in permanent aquifer-system storage loss.

Contacts: Michelle Sneed
Date published: October 15, 2018
Status: Completed

Debris-Flow Forecasts Before Wildfires

Release Date: OCTOBER 15, 2018

USGS scientists have been pursuing a way to assess debris-flow hazards before a fire occurs.

Date published: October 3, 2018
Status: Active

Implementing New Acoustic Monitoring Techniques in the Trinity River

Accurate river-sediment data is fundamental to planning and managing river restoration efforts on the Trinity River, and throughout the world’s waterways. The USGS has developed a “hydrophone” that enables scientists to listen to sediment particles as they move along the riverbed in order to inexpensively and reliably record near-continuous sediment-bedload-transport data. For this study,...

Date published: August 30, 2018
Status: Active

Yucaipa Subbasin Integrated Hydrologic Model

The USGS is developing a hydrologic model of the Yucaipa Subbasin to aid in evaluating and managing the groundwater resources in the area. The study results will provide a greater understanding of the geohydrology of the subbasin, and aid in the development of a groundwater-monitoring plan, as well as in the evaluation of potential hydrologic effects of future groundwater development and...

Contacts: Geoff Cromwell
Date published: August 30, 2018
Status: Active

Microbial Biogeochemistry — Menlo Park, California

About the Research

The Environmental Health Program collaborates with microbiologists at the Microbial Biogeochemistry Laboratory to develop and apply innovative methods to measure key microbial processes. These methods are used to better understand how major biogeochemical cycles (carbon, nitrogen, sulfur, and iron) interact with and control the speciation and fate of...

Date published: August 28, 2018
Status: Active

Organic Chemistry Research — Sacramento, California

About the Research

The Environmental Health Program collaborates with chemists and hydrologists at the Organic Chemistry Research Laboratory (OCRL) to develop targeted analytical methods for the quantitation of chemicals that can impact the health of organisms and humans. The scientists have developed methods in a wide variety of environmental media; in addition to...

Date published: August 27, 2018
Status: Completed

Increasing Soil Organic Carbon to Mitigate Greenhouse Gases and Increase Climate Resiliency for California

Rising air temperatures are projected to continue to drive up urban, agricultural, and rangeland water use, straining both surface and groundwater resources. Scientific studies have shown that managing farms, ranches, and public lands to increase soil carbon can increase soil waterholding capacity and increase hydrologic benefits such as increased baseflows and aquifer recharge, reduced...

Contacts: Michelle Stern
Date published: August 24, 2018
Status: Active

Yucaipa Valley Hydrogeology

This study assesses the quality of water in the Yucaipa area, primarily in the Yucaipa plain. This hydrogeology study will aid local water purveyors in understanding and evaluating local resources and using those resources effectively in combination with water imported from northern California and from the adjacent San Bernardino area.

Contacts: Gregory Mendez
Date published: August 5, 2018
Status: Active

Global Hyperspectral Imaging Spectroscopy of Agricultural-Crops & Vegetation (GHISA)

This webpage showcases the key research advances made in hyperspectral remote sensing of agricultural crops and vegetation over the last 50 years. There are three focus areas:

Date published: July 16, 2018
Status: Completed

A New Map of Rodgers Creek Fault in Sonoma County, California

Release Date: JULY 16, 2018

A new more detailed and higher resolution map of the Rodgers Creek Fault in Sonoma County, California, has been produced using aerial photography and hillshade imagery derived from LiDAR data.

Filter Total Items: 569
Date published: January 1, 2019

Time-series oceanographic data from the Monterey Canyon, CA October 2015 - March 2017

Time-series data of water depth, velocity, turbidity, and temperature were acquired between 5 October 2015 and 21 March 2017 within the Monterey Canyon off of Monterey, CA, USA.
In order to better understand the triggering, progression and evolution of turbidity currents in Monterey Submarine Canyon, an experiment was designed to directly measure velocity, suspended sediment an

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood-hazard projections: 1-year storm in Santa Barbara County

This data contains geographic extents of projected coastal flooding, low-lying vulnerable areas, and maximum/minimum flood potential (flood uncertainty) associated with the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-ind

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 ocean-currents projections: average conditions in Santa Barbara County

This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scen

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood-hazard projections: 100-year storm in San Luis Obispo County

This data contains geographic extents of projected coastal flooding, low-lying vulnerable areas, and maximum/minimum flood potential (flood uncertainty) associated with the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-ind

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood-hazard projections: 20-year storm in San Luis Obispo County

This data contains geographic extents of projected coastal flooding, low-lying vulnerable areas, and maximum/minimum flood potential (flood uncertainty) associated with the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-ind

Date published: January 1, 2019

Annual streamflow, runoff and baseflow, estimated for the period of record using six hydrograph-separation methods, for 312 gaged basins in the Northwest Volcanic Aquifer Study Area, USA, 1904-2015.

The U.S. Geological Survey’s Water Availability and Use Study Program (WAUSP) (https://water.usgs.gov/ogw/gwrp/activities/regional.html) supports quantitative assessments of groundwater availability in areas of critical importance. As part of a WAUSP study in the arid to semi-arid Northwest Volcanic Aquifer Study Area (...

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood depth and duration projections: average conditions in San Francisco County

This data contains maximum depth of flooding (cm) in the region landward of the present-day shoreline for the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-le

Date published: January 1, 2019

Atmospheric-loading frequency response functions and groundwater-levels filtered for the effects of atmospheric loading and solid Earth tides for three monitoring wells near Mammoth Lakes, California, 2015 - 2017.

The data include atmospheric-loading frequency response functions (table 1) and filtered detrended and reconstructed (trends restored) groundwater-levels (tables 2 to 4) computed for selected, parsed time series for three USGS monitoring wells [28A-25-1 (373904118570701); 28A-25-2 (373904118570702); and 14A-25-1 (373927118571701)], and the associated hourly res

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood-hazard projections: 100-year storm in Santa Barbara County

This data contains geographic extents of projected coastal flooding, low-lying vulnerable areas, and maximum/minimum flood potential (flood uncertainty) associated with the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-ind

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 ocean-currents projections: 20-year storm in Santa Barbara County

This data contains maximum model-derived ocean currents (in meters per second) for the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scen

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 water-level projections: average conditions in San Luis Obispo County

This data contains model-derived total water levels (in meters) for the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. Projecti

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood depth and duration projections: average conditions in San Mateo County

This data contains maximum depth of flooding (cm) in the region landward of the present-day shoreline for the sea-level rise (SLR) and storm condition indicated.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-le

Filter Total Items: 440
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Year Published: 2009

Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008

Acoustic telemetry was used to obtain the movement histories of 915 juvenile fall-run Chinook salmon (Oncorhynchus tshawytscha) through the lower San Joaquin River and Sacramento-San Joaquin Delta, California, in 2008. Data were analyzed within a release-recapture framework to estimate survival, route distribution, and detection probabilities...

Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.
Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008; 2009; OFR; 2009-1204; Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.

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Year Published: 2009

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, October 2008 and January 2009

This report presents the results for two sampling periods (October 2008 and January 2009) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were...

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
Total Selenium and Selenium Species in Irrigation Drain Inflows to the Salton Sea, California, October 2008 and January 2009; 2009; OFR; 2009-1123; May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

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Year Published: 2009

Population Dynamics of Adult Lost River (Deltistes luxatus) and Shortnose (Chasmistes brevirostris) Suckers in Clear Lake Reservoir, California, 2006-08

We report results from ongoing research into the population dynamics of endangered Lost River and shortnose suckers in Clear Lake Reservoir, California. Results are included for sampling that occurred from fall 2006 to spring 2008. We summarize catches and passive integrated transponder tagging efforts from trammel net sampling in fall 2006 and...

Barry, Patrick M.; Janney, Eric C.; Hewitt, David A.; Hayes, Brian S.; Scott, Alta C.
Population Dynamics of Adult Lost River (Deltistes luxatus) and Shortnose (Chasmistes brevirostris) Suckers in Clear Lake Reservoir, California, 2006-08; 2009; OFR; 2009-1109; Barry, Patrick M.; Janney, Eric C.; Hewitt, David A.; Hayes, Brian S.; Scott, Alta C.

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Year Published: 2009

Cone penetration test and soil boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California

Aquifer-system deformation associated with ground-water-level changes is being investigated cooperatively by the U.S. Geological Survey (USGS) and the East Bay Municipal Utility District (EBMUD) at the Bayside Groundwater Project (BGP) near the modern San Francisco Bay shore in San Lorenzo, California. As a part of this project, EBMUD has proposed...

Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C.
Cone Penetration Test and Soil Boring at the Bayside Groundwater Project Site in San Lorenzo, Alameda County, California; 2009; OFR; 2009-1050; Bennett, Michael J.; Sneed, Michelle; Noce, Thomas E.; Tinsley, John C., III

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Year Published: 2009

Summary of Migration and Survival Data from Radio-Tagged Juvenile Coho Salmon in the Trinity River, Northern California, 2008

The survival of hatchery-origin juvenile coho salmon from the Trinity River Hatchery was estimated as they migrated seaward through the Trinity and Klamath Rivers. The purpose of the study was to collect data for comparison to a similar study in the Klamath River and provide data to the Trinity River Restoration Program. A total of 200 fish fitted...

Beeman, John W.; Hansel, Hal; Juhnke, Steve; Stutzer, Greg
Summary of Migration and Survival Data from Radio-Tagged Juvenile Coho Salmon in the Trinity River, Northern California, 2008; 2009; OFR; 2009-1092; Beeman, John W.; Hansel, Hal; Juhnke, Steve; Stutzer, Greg

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Year Published: 2009

Data files for ground-motion simulations of the 1906 San Francisco earthquake and scenario earthquakes on the Northern San Andreas Fault

This data set contains results from ground-motion simulations of the 1906 San Francisco earthquake, seven hypothetical earthquakes on the northern San Andreas Fault, and the 1989 Loma Prieta earthquake. The bulk of the data consists of synthetic velocity time-histories. Peak ground velocity on a 1/60th degree grid and geodetic displacements from...

Aagaard, Brad T.; Barall, Michael; Brocher, Thomas M.; Dolenc, David; Dreger, Douglas; Graves, Robert W.; Harmsen, Stephen; Hartzell, Stephen H.; Larsen, Shawn; McCandless, Kathleen; Nilsson, Stefan; Petersson, N. Anders; Rodgers, Arthur; Sjogreen, Bjorn; Zoback, Mary Lou
Data Files for Ground-Motion Simulations of the 1906 San Francisco Earthquake and Scenario Earthquakes on the Northern San Andreas Fault; 2009; DS; 413; Aagaard, Brad; Barall, Michael; Brocher, Thomas M.; Dolenc, David; Dreger, Douglas; Graves, Robert W.; Harmsen, Stephen; Hartzell, Stephen; Larsen, Shawn; McCandless, Kathleen; Nilsson, Stefan; Petersson, N. Anders; Rodgers, Arthur; Sjogreen, Bjorn; Zoback, Mary Lou

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Year Published: 2009

Total selenium and selenium species in irrigation drain inflows to the Salton Sea, California, April and July 2008

This report presents the results for two sampling periods (April 2008 and July 2008) during a 4-year monitoring program to characterize selenium concentrations in selected irrigation drains flowing into the Salton Sea, California. Total selenium, selenium species (dissolved selenite, selenate, organoselenium), and total suspended solids were...

May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.
Total Selenium and Selenium Species in Irrigation Drain Inflows to the Salton Sea, California, April and July 2008; 2009; OFR; 2009-1011; May, Thomas W.; Walther, Michael J.; Saiki, Michael K.; Brumbaugh, William G.

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Year Published: 2009

Summary of Survival Data from Juvenile Coho Salmon in the Klamath River, Northern California, 2008

A study to estimate the effects of Iron Gate Dam discharge on ESA-listed juvenile coho salmon during their seaward migration to the ocean was begun in 2005. Estimates of survival through various reaches of river downstream from the dam were completed in 2006, 2007, and 2008 as part of this process. This report describes the estimates of survival...

Beeman, John W.; Juhnke, Steven; Hansel, Hal C.
Summary of Survival Data from Juvenile Coho Salmon in the Klamath River, Northern California, 2008; 2009; OFR; 2009-1019; Beeman, John W.; Juhnke, Steven; Hansel, Hal C.

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Year Published: 2009

A search in strainmeter data for slow slip associated with triggered and ambient tremor near Parkfield, California

We test the hypothesis that, as in subduction zones, slow slip facilitates triggered and ambient tremor in the transform boundary setting of California. Our study builds on the study of Peng et al. (2009) of triggered and ambient tremor near Parkfield, California during time intervals surrounding 31, potentially triggering, M ≥ 7.5 teleseismic...

Smith, E.F.; Gomberg, J.
A search in strainmeter data for slow slip associated with triggered and ambient tremor near Parkfield, California; 2009; Article; Journal; Journal of Geophysical Research B: Solid Earth; Smith, E. F.; Gomberg, J.

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Year Published: 2009

Habitat requirements of the endangered California freshwater shrimp (Syncaris pacifica) in lagunitas and Olema creeks, Marin County, California, USA

This study was conducted to better understand the habitat requirements and environmental limiting factors of Syncaris pacifica, the California freshwater shrimp. This federally listed endangered species is native to perennial lowland streams in a few watersheds in northern California. Field sampling occurred in Lagunitas and Olema creeks at...

Martin, Barbara A.; Saiki, Michael K.; Fong, Darren
Habitat requirements of the endangered California freshwater shrimp (Syncaris pacifica) in lagunitas and olema creeks, Marin County, California, USA; 2009; Article; Journal; Journal of Crustacean Biology; Martin, B. A.; Saiki, M. K.; Fong, D.

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Year Published: 2009

Linking habitat quality with trophic performance of steelhead along forest gradients in the South Fork Trinity River Watershed, California

We examined invertebrate prey, fish diet, and energy assimilation in relation to habitat variation for steelhead Oncorhynchus mykiss (anadromous rainbow trout) and rainbow trout in nine low-order tributaries of the South Fork Trinity River, northern California. These streams spanned a range of environmental conditions, which allowed us to use...

McCarthy, Sarah G.; Duda, Jeffrey J.; Emlen, John M.; Hodgson, Garth R.; Beauchamp, David A.

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Year Published: 2009

Moderate rates of late Quaternary slip along the northwestern margin of the Basin and Range Province, Surprise Valley fault, northeastern California

The 86-km-long Surprise Valley normal fault forms part of the active northwestern margin of the Basin and Range province in northeastern California. We use trench mapping and radiocarbon, luminescence, and tephra dating to estimate displacements and timing of the past five surface-rupturing earthquakes on the central part of the fault near...

Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Mahan, Shannon; Lidke, David J.
Moderate rates of late Quaternary slip along the northwestern margin of the Basin and Range Province, Surprise Valley fault, northeastern California; 2009; Article; Journal; Journal of Geophysical Research B: Solid Earth; Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Mahan, Shannon A.; Lidke, David J.

Filter Total Items: 1,126
A RestoreNet garden with plots covered by white cloth.
August 31, 2018

RestoreNet garden testing seedling establishment.

The RestoreNet gardens test seedlings of priority restoration species across the Southwest. This is a recently installed garden located in the juniper woodlands of the Colorado Plateau. The experiemental network will support land managers by providing insight into various restoration techniques, including testing seedlings vs seeds.

city skyline with tall buildings lit up at night and bridge in left foreground
August 15, 2018

The Bay Bridge and the Oakland city skyline

The nighttime Oakland city skyline as seen from San Francisco with the Bay Bridge in the foreground

August 14, 2018

Image of the Week - Mendocino Fire

Landsat 8 captured satellite views of California’s largest wildfire on record in the summer of 2018. The Mendocino Complex Fire in northern California is a combination of two fires: the Ranch Fire and the River Fire. 

Both fires started July 27, and hot, dry, windy conditions caused them to spread rapidly. Landsat 8 imaged the area the day before the fires broke out

Satellite image of fire destruction.
August 11, 2018

Mendocino Complex Fire Scorches Northern California

Landsat 8 captured satellite views of California's largest wildfire on record in the summer of 2018. The Mendocino Complex fire in northern California is a combination of two fires: the Ranch Fire and the River Fire.

Three people stand at the base of a grassless, rocky, steep slope looking up at landslides caused by an extreme rain event.
August 2, 2018

Tuolumne watershed landslides

USGS scientists examining landslides in the Tuolumne watershed, California, caused by an extreme rain event in 2018.

Map highlighting sampling locations of 339 Northern Spotted Owls used in Miller, et al, 2018
August 2, 2018

Figure 1 from Miller, et al, 2018

Map highlighting sampling locations of 339 Northern Spotted Owls used in Miller, et al, 2018

July 26, 2018

PubTalk 7/2018— Extreme acid mine drainage at Iron Mountain California

Title: Iron Mountain, California: An Extreme Acid Mine Drainage Environment

  • "The world's most acid water" — explaining negative pH
  • Colorful mineral salts that store metals and acidity in underground mine workings
  • Microbial iron oxidation and formation of pipe scale in the water treatment system
  • Challenges and successes of
View from the sky of a jagged coastline with many roads, houses, a park, and other buildings nearby.
July 25, 2018

Natural Bridges

Natural Bridges State Beach, shown here in the middle of the photo, is nestled amongst coastal neighborhoods in the southwestern part of Santa Cruz, California. View is looking south. The offices of the USGS Pacific Coastal and Marine Science Center are just a few hundred feet north, outside the bottom portion of the photograph.

View from the sky of a large estuary with large and small waterways surrounded by villages and agriculture, hills in background.
July 25, 2018

Elkhorn Slough

Elkhorn Slough is a tidal river delta, salt marsh, and estuary in Monterey County, California. It is near the community of Moss Landing and is fed by Carneros Creek.

Photographs looking at a coastal cliff with a road covered by a landslide, then debris is cleared and road is repaired.
July 18, 2018

Mud Creek landslide changes March 2017-June 2018

USGS scientists produced an animated GIF in coordination with the California Department of Transportation (Caltrans) re-opening of State Highway 1 through Big Sur on July 18, 2018. In 2017, the massive Mud Creek landslide buried a quarter-mile of the famous coastal route with rocks and dirt more than 65 feet deep. As part of a new research project to monitor erosion along

...
adult male harrier
July 13, 2018

Adult Male Northern Harrier (Circus cyaneus)

An adult male Northern Harrier (Circus cyaneus) surveys Suisun Marsh, CA. Males are known for their beautiful, steel-gray plumage.

Salt marsh harvest mouse
July 13, 2018

Endangered Salt Marsh Harvest Mouse (Reithrodontomys raviventris)

A Federally endangered salt marsh harvest mouse (Reithrodontomys raviventris) climbs a branch.

Filter Total Items: 975
A picture of low water levels of the American River
September 23, 2015

The rising temperatures in many of California's rivers have become potentially lethal to anadromous fish, and other fish species. Even in rivers controlled by reservoirs, where operators have traditionally been able to help control river temperature by timed releases, the combination of low flows, reduced cold-water pools in reservoirs and high air temps has resulted in elevated river temps.

Image: Severe Coastal Erosion During an El Niño Storm
September 21, 2015

SANTA CRUZ, Calif. — The projected upsurge of severe El Niño and La Niña events will cause an increase in storm events leading to extreme coastal flooding and erosion in populated regions across the Pacific Ocean, according to a multi-agency study published today in Nature Geoscience.

Image: Sea Otter Ready for a Nap
September 17, 2015

SANTA CRUZ, Calif. — The recovery of southern sea otters appears to have taken an upturn, according to results from the annual California sea otter survey released by the U.S. Geological Survey today. Yet despite an overall increase in sea otter abundance, sharks have been “taking a bite” out of the portion of the population that could fuel expansion into new areas.

Illustration: Study area showing boundaries of each of the seven greater sage-grouse management zones
September 10, 2015

OAKHURST, Calif. -- Overall fire threats to greater sage-grouse habitat are much higher in the western part of the species’ range than in the eastern part, according to a U.S. Geological Survey fire threats assessment study published today.

USGS science for a changing world logo
September 10, 2015

MENLO PARK, Calif. — Some of the inner workings of Earth’s subduction zones and their “megathrust” faults are revealed in a paper published today in the journal “Science.” U.S. Geological Survey scientist Jeanne Hardebeck calculated the frictional strength of subduction zone faults worldwide, and the stresses they are under.

Image: USGS Documents 2015 Drought
September 8, 2015

U.S. Geological Survey hydrologic technicians are currently taking measurements from hundreds of streams and rivers across the western United States as part of a low flow study.

2015 Chile-US Bi-national Exchange participants work together on vo...
September 8, 2015

Scientists, civil authorities, and emergency managers from Chile and the U.S. met in California to discuss the challenges of effective volcanic hazard education, response planning, hazard mitigation, and risk reduction, as part of the second Binational Exchange program for Volcanic Risk Reduction in the Americas.

Image: Moon over Half Dome
September 7, 2015

Despite sounding like something out of Harry Potter, a batholith is a type of igneous rock that forms when magma rises into the earth’s crust, but does not erupt onto the surface. The magma cools beneath the earth’s surface, forming a rock structure that extends at least one hundred square kilometers across (40 square miles), and extends to an unknown depth.

2015 Chile-US Bi-national Exchange participants work together on vo...
September 3, 2015

Scientists, civil authorities, and emergency managers from Chile and the U.S. met in California to discuss the challenges of effective volcanic hazard education, response planning, hazard mitigation, and risk reduction, as part of the second Bi-national Exchange program for Volcanic Risk Reduction in the Americas.

imaging from Mars
September 2, 2015

A new analysis of the largest known deposit of carbonate minerals on Mars helps limit the range of possible answers about how and why Mars changed from a world with watery environments billions of years ago to the arid Red Planet of today.

Image: Drakes Peak
August 24, 2015

SEQUOIA AND KINGS CANYON, Calif. — A new paper published today in Science magazine has synthesized existing studies on the health of temperate forests across the globe and found a sobering diagnosis. Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening some of these forests with transformation.

August lecture flyer thumbnail
August 24, 2015

The earthquake rate has dramatically increased in the central United States in the last six years. Oklahoma had more magnitude 3 or greater earthquakes in 2014 than California.