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: 421
Date published: October 29, 2018
Status: Completed

Hydrogeologic Characterization of the Cox/San Andreas Oasis, California

The Bureau of Land Management (BLM) manages the Dos Palmas Oasis complex on the northeastern side of the Salton Sea for the maintainence of threatened and endangered species. This Oasis complex represents a rare area of riparian/wetland habitat in the midst of an extremely arid desert region. Anthropogenic development of water resources during the 1900s depleted natural groundwater supplies...

Date published: October 29, 2018
Status: Completed

Development of Numeric Flow Criteria to Support Freshwater Biological Objectives and Hydrologic Modification Management in California's Wadeable Streams

The State Water Resources Control Board (SWRCB) of California has initiated a process to develop numerical biological objectives for wadeable freshwater streams and rivers for the entire state. Use of biological endpoints for regulatory or compliance purposes requires the ability to relate specific stressors...

Contacts: Larry Brown
Date published: October 29, 2018
Status: Active

Monitoring the Impacts of the Rim Fire on Tuolumne River Water Quality

The Rim Fire has burned over 400 square miles of the Tuolumne River and Merced River watersheds in central California and is now the 3rd largest wildfire in state history. The burn area is largely on the Tuolumne between Hetch Hetchy Reservoir and Don Pedro Reservoir, both of which serve as critical sources of drinking water and irrigation water to San Francisco Bay area and Central Valley...

Contacts: Scott A Wright
Date published: October 26, 2018
Status: Completed

Depth-Dependent groundwater flow, age, and chemistry in relation to solvent contamination in a production well, Tulare Lake basin, California

The Tulare Lake basin in the southern Central Valley of California is heavily dependent upon groundwater for drinking water supply but groundwater in this basin is threatened by a wide array of issues. Groundwater aquifers in the alluvial fan sediments derived from the Sierra Nevada on the eastern side of the Tulare Lake basin are highly productive aquifers that are vulnerable to contamination...

Date published: October 26, 2018
Status: Active

Determination of the geohydrologic characteristics of the boundary between the Mojave River and Antelope Valley groundwater basins, California

The Mojave Basin Area was adjudicated in 1993 and the Mojave Water Agency (MWA) was appointed as Watermaster to ensure that water rights are allocated according to the Court Judgment (Riverside County Superior Court, 1996). Established in 1960, the southwestern boundary of MWA’s management area is not a hydrologic boundary but instead coincides roughly with the boundary between San Bernardino...

Date published: October 26, 2018
Status: Active

Coordinated Pesticide Reconnaissance Study of Surface Waters in California

Pesticides are used throughout the State of California in both urban and agricultural settings and are routinely detected in surface water. Each year, new pesticides are introduced to the market and often become detected in surface water. It can take several years or more for routine monitoring programs to acquire the capability to detect new and understudied pesticides of concern because...

Contacts: James Orlando
Date published: October 26, 2018
Status: Completed

Atmospheric Deposition Contributions to Mercury Yields in Select Watersheds in the Western United States and Canada

The atmosphere plays an important role in the delivery to and cycling of mercury (Hg) in the environment and it can be a major source of Hg contamination to surface waters. Globally, atmospheric deposition of Hg is the primary source of Hg related concerns for human and ecosystem health (Fitzgerald and others, 1998). In California and other areas in the United States, Hg use in gold and silver...

Date published: October 24, 2018
Status: Active

Monitoring Mercury and Methylmercury in Water, Sediment and Biota in Combie Reservoir Before and After Dredging and Mercury Removal

Dredging to maintain water storage capacity by the Nevada Irrigation District (NID) occurred at Lake Combie reservoir, one of several reservoirs along the Bear River, California over the past 40 years on an as-needed basis to maintain water storage capacity. Maintenance dredging operations were halted by the Central Valley Regional Water...

Date published: October 24, 2018
Status: Active

The Effects of Artificial Recharge on Nitrate Concentrations in Groundwater in the Joshua Tree Subbasin, California

The Joshua Basin Water District (JBWD) is implementing an artificial groundwater recharge program to reverse the decline of groundwater levels and to store water in the Joshua Tree groundwater subbasin of the Morongo groundwater basin (~100 mi east of Los Angeles, CA).

Contacts: David O'Leary
Date published: October 24, 2018
Status: Active

Subsidence from Aquifer-Storage and Recovery in the East Bay Plain

The East Bay Municipal Utility District (EBMUD) has proposed to store and recover as much as 10 million gallons of water per day (MGD) at an aquifer storage and recovery (ASR) site, the Bayside Groundwater Project. Water will be stored in a 100-ft sequence of coarse-grained sediment (the "Deep Aquifer") underlying the East Bay Plain and the adjacent Niles Cone ground-water basin.

Contacts: Michelle Sneed
Date published: October 23, 2018
Status: Active

Webinar: Linking Remote Sensing and Bird Behavior Data to Understand the Impacts of Drought on Waterfowl

View this webinar to learn how scientists are exploring the impacts of drought on waterfowl.

Date published: October 23, 2018
Status: Active

Installation of two multiple-well monitoring sites near a proposed supplemental recharge well project, Central Basin, Los Angeles County, Federal Fiscal Year 2016

The Water Replenishment District of Southern California (WRD) is planning to construct an advanced water treatment facility and three supplemental injection wells in a recharge area in the coastal plain of Los Angeles County. 

Filter Total Items: 583
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

Depth to Transition—Point Sur to Point Arguello, California

This part of DS 781 presents data for the depth-to-transition map of the Point Sur to Point Arguello, California, region. The raster data file is included in the “DepthToTransition_PointSurToPointArguello.zip,” which is accessible from https://doi.org/10.5066/P97CZ0T7.
As part of the USGS's California State Waters Mapping Project, a 50-m...

Date published: January 1, 2019

CoSMoS (Coastal Storm Modeling System) Central California v3.1 flood depth and duration projections: 20-year storm 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

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: 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

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

Filter Total Items: 481
Publication Thumbnail
Year Published: 2013

Adjusting survival estimates for premature transmitter failure: A case study from the Sacramento-San Joaquin Delta

In telemetry studies, premature tag failure causes negative bias in fish survival estimates because tag failure is interpreted as fish mortality. We used mark-recapture modeling to adjust estimates of fish survival for a previous study where premature tag failure was documented. High rates of tag failure occurred during the Vernalis Adaptive...

Holbrook, Christopher M.; Perry, Russell W.; Brandes, Patricia L.; Adams, Noah S.

Publication Thumbnail
Year Published: 2013

Late quaternary slip-rate variations along the Warm Springs Valley fault system, northern Walker Lane, California-Nevada border

The extent to which faults exhibit temporally varying slip rates has important consequences for models of fault mechanics and probabilistic seismic hazard. Here, we explore the temporal behavior of the dextral‐slip Warm Springs Valley fault system, which is part of a network of closely spaced (10–20 km) faults in the northern Walker Lane (...

Gold, Ryan; dePolo, Craig; Briggs, Richard W.; Crone, Anthony; Goss, John

Publication Thumbnail
Year Published: 2013

Assessment of juvenile coho salmon movement and behavior in relation to rehabilitation efforts in the Trinity River, California, using PIT tags and radiotelemetry

Coho salmon (Oncorhynchus kisutch) of the Southern Oregon/Northern California Coast (SONCC) Evolutionarily Significant Unit (ESU) is federally listed as a threatened species. The Trinity River Restoration Program (TRRP) is rehabilitating the Trinity River to restore coho salmon (coho) and other salmonid populations. In order to evaluate the...

Chase, Robert; Hemphill, Nina; Beeman, John; Juhnke, Steve; Hannon, John; Jenkins, Amy M.
Assessment of juvenile coho salmon movement and behavior in relation to rehabilitation efforts in the Trinity River, California, using PIT tags and radiotelemetry; 2013; Article; Journal; Environmental Biology of Fishes; Chase, Robert ; Hemphill, Nina ; Beeman, John ; Juhnke, Steve ; Hannon, John ; Jenkins, Amy M.

Publication Thumbnail
Year Published: 2012

2011 Georgiana Slough non-physical barrier performance evaluation project report

<p>The Sacramento River and its tributaries support populations of anadromous fish species including winter-run, spring-run, fall-run, and late fall–run Chinook salmon (Oncorhynchus tshawytscha); and steelhead (O. mykiss). Several of these species are listed as threatened or endangered under the California Endangered Species Act (CESA...

Romine, Jason G.; Perry, Russell W.; Liedtke, Theresa L.

Publication Thumbnail
Year Published: 2012

Effect of brook trout removal from a spawning stream on an adfluvial population of Lahontan cutthroat trout

Independence Lake (Nevada and Sierra counties, California) harbors the only extant native population of Lahontan cutthroat trout Oncorhynchus clarkii henshawi in the Truckee River system and one of two extant adfluvial populations in the Lahontan basin. The persistence of this population has been precarious for more than 50 years, with spawning...

Scoppettone, G. Gary; Rissler, Peter H.; Shea, Sean P.; Somer, William
Effect of brook trout removal from a spawning stream on an adfluvial population of Lahontan cutthroat trout; 2012; Article; Journal; North American Journal of Fisheries Management; Scoppettone, G. Gary; Rissler, Peter H.; Shea, Sean P.; Somer, William

Publication Thumbnail
Year Published: 2012

Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California

Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader...

Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

Publication Thumbnail
Year Published: 2012

Using a non-physical behavioural barrier to alter migration routing of juvenile Chinook salmon in the Sacramento–San Joaquin River Delta

Anthropogenic alterations to river systems, such as irrigation and hydroelectric development, can negatively affect fish populations by reducing survival when fish are routed through potentially dangerous locations. Non-physical barriers using behavioural stimuli are one means of guiding fish away from such locations without obstructing water flow...

Perry, R.W.; Romine, J.G.; Adams, N.S.; Blake, A.R.; Burau, J.R.; Johnston, S.V.; Liedtke, T.L.

Publication Thumbnail
Year Published: 2012

Trimming the UCERF2 hazard logic tree

The Uniform California Earthquake Rupture Forecast 2 (UCERF2) is a fully time‐dependent earthquake rupture forecast developed with sponsorship of the California Earthquake Authority (Working Group on California Earthquake Probabilities [WGCEP], 2007; Field et al., 2009). UCERF2 contains 480 logic‐tree branches reflecting choices among nine...

Porter, Keith A.; Field, Edward H.; Milner, Kevin

Publication Thumbnail
Year Published: 2012

Survival and migration route probabilities of juvenile Chinook salmon in the Sacramento-San Joaquin River Delta during the winter of 2009-10

Juvenile Chinook salmon (Oncorhynchus tshawytscha) emigrating from natal tributaries of the Sacramento River may use a number of migration routes to negotiate the Sacramento-San Joaquin River Delta (hereafter, "the Delta"), each of which may influence their probability of surviving. We applied a mark-recapture model to data from acoustically...

Perry, Russell W.; Romine, Jason G.; Brewer, Scott J.; LaCivita, Peter E.; Brostoff, William N.; Chapman, Eric D.

Publication Thumbnail
Year Published: 2012

2011 Georgiana Slough non-physical barrier performance evaluation project report

The Sacramento River and its tributaries support populations of anadromous fish species including winter-run, spring-run, fall-run, and late fall–run Chinook salmon (Oncorhynchus tshawytscha); and steelhead (O. mykiss). Several of these species are listed as threatened or endangered under the California Endangered Species Act (CESA), federal...

Reeves, Ryan R.; McQuirk, Jacob; Ameri, Khalid; Perry, Russell W.; Romine, Jason G.; Liedtke, Theresa L.; Burau, Jon R.; Blake, Aaron R.; Fitzer, Chris; Smith, Natalie; Pagliughi, Steve; Johnston, Sam; Kumagai, Kevin; Cash, Kenneth

Publication Thumbnail
Year Published: 2012

Preliminary juvenile Lost River and shortnose sucker investigations in Clear Lake, California--2011 pilot study summary

Poor recruitment appears to limit the recovery of Lost River and shortnose sucker populations in Clear Lake Reservoir, California, but the cause is unknown. Adult suckers migrate up Willow Creek and its tributaries to spawn in some years, but low flow in Willow Creek may inhibit spawning migrations in other years. It is unclear whether spawning is...

Burdick, Summer M.; Rasmussen, Josh
Preliminary juvenile Lost River and shortnose sucker investigations in Clear Lake, California--2011 pilot study summary; 2012; OFR; 2012-1180; Burdick, Summer M.; Rasmussen, Josh

Publication Thumbnail
Year Published: 2012

Objective definition of rainfall intensity-duration thresholds for the initiation of post-fire debris flows in southern California

Rainfall intensity–duration (ID) thresholds are commonly used to predict the temporal occurrence of debris flows and shallow landslides. Typically, thresholds are subjectively defined as the upper limit of peak rainstorm intensities that do not produce debris flows and landslides, or as the lower limit of peak rainstorm intensities that initiate...

Staley, Dennis; Kean, Jason W.; Cannon, Susan H.; Schmidt, Kevin; Laber, Jayme L.
Objective definition of rainfall intensity-duration thresholds for the initiation of post-fire debris flows in southern California; 2012; Article; Journal; Landslides; Dennis Staley; Jason W Kean; Susan H Cannon; Schmidt, Kevin M.; Laber, Jayme L.

Filter Total Items: 1,116
Researcher in Mojave Desert
November 29, 2018

Researcher in Mojave Desert

One of 1,695 repeat photographs taken to provide context for the classification of the Central Mojave Desert into various vegetation classes.

November 29, 2018

PubTalk 11/2018 - California Birds

Title: The Least Bell's Vireo - A flagship species for riparian ecosystem conservation

The Least Bell's Vireo (Vireo bellii pusillus) is a songbird that is endangered in California:

  • What type of research is the USGS doing to help understand the threats these and other birds face?
  • How has our research during the last 30 years
Snow falls on USGS Hydrologist, Joe Nawikas, as he collects groundwater samples in Mammoth, California.
November 28, 2018

Collecting Groundwater Samples in Mammoth, CA

Snow falls on USGS Hydrologist, Joe Nawikas, as he collects groundwater samples in Mammoth, California.

Scientist writing on clipboard, with small seismometer on the ground and mountains in the background
November 16, 2018

Collecting geophysics data at Pinnacles National Park

Research Hydrologist Paul Hsieh collects seismic data during a groundwater study at Pinnacles National Park in California. The red seismometer on the ground measures ambient seismic noise, which includes microtremors induced by wind, ocean waves, and human activity. The seismic data collected can be used to estimate unconsolidated sediment thickness, map the bedrock

...
Attribution: Water Resources
November 16, 2018

Image of the Week - California Wildfires

Satellites have captured views of the numerous major fires burning in California.

An image acquired on November 9, 2018, from NASA’s MODIS sensor on the Terra satellite shows smoke pouring out of two major fires, the Camp Fire and the Woolsey Fire, which both ignited the day before.

In the north, the Camp Fire quickly became the deadliest wildfire in the

Image from an application that navigates users through USGS National Oil and Gas Assessment Provinces
November 14, 2018

National Oil and Gas Assessment Provinces

This is a graphic from the USGS National Oil and Gas Assessment Explorer application, which allows user to drill into 70 oil and gas assessment provinces throughout the United States.

Satellite picture showing the Woolsey fire in California
November 8, 2018

Fires Burning Across California

Satellites have captured views of the numerous major fires burning in California.

Dark image of a coastal area shows standard deviation of pixel density for 10 minutes, brighter areas mean more movement.
November 8, 2018

Sunset State Beach variance image

Image from video camera along Sunset State Beach in Watsonville, CA, looking northwest. Every half hour during daylight hours, the camera shoots video for 10 minutes. This variance image shows the standard deviation of pixel intensity throughout the video frames, useful for determining how much variation or movement is occurring at a given location. Brighter tones indicate

...
View of the underside of an airplane wing with a sunset over the ocean, with islands, in the background.
November 1, 2018

Channel Islands National Park from an aerial photographic survey

View of Channel Islands National Park from a Fall 2018 aerial photographic survey.

The Seabird Studies Team at the USGS Western Ecological Research Center is conducting aerial photographic surveys of the ocean off central and southern California to create comprehensive maps of seabird and marine mammal distributions.

October 31, 2018

Drone Footage of Whiskeytown National Recreation Area after Carr Fire

Drone footage of Whiskeytown National Recreation area in Northern California in October 2018, captured by drone pilot and USGS WERC ecologist Chase Freeman.

USGS WERC is using drone imagery to understand how the 2018 Carr Fire affected ecosystems and cultural resources. The study, a collaboration with the National Park Service (NPS), focuses on Whiskeytown National

October 25, 2018

PubTalk 10/2018 — Post-fire debris flow early warning

Title: Post-Fire Debris-Flow Early Warning: The case for forecast-based warning systems

  • Post-fire debris flows can initiate after only a few minutes of intense rain, and during the first storm following wildfire.
  • Early warning systems must provide sufficient time to make informed decisions and take reasonable preventative action.
  • If you're
Pacific fisher on a tree looking into a bait box
October 24, 2018

Pacific fisher trying to grab a chicken dinner from the bait box

USGS scientists are documenting the distribution of three mid-sized mammalian carnivores – or mesocarnivores –in the Klamath Network Parks using remote cameras and hair snares. Little is known about the status of Pacific fishers, Pacific martens, and Sierra Nevada red foxes living in the Klamath Network, which include Crater Lake National Park, Lassen Volcanic National

...
Filter Total Items: 987
This is a photo of Ubehebe Crater.
March 25, 2016

New research by scientists at CalVO indicates that Ubehebe Craters formed about 2100 years ago during a single eruptive event. Ubehebe Craters are a lone cluster of volcanic craters in the northern half of California's Death Valley National Park.

Picture of a ground water display
March 25, 2016

California Water Science Center scientist teach water quality issues to Orange County students

California's hotter drought has already killed millions of trees, particularly in low-elevation forests.
March 22, 2016

California's hotter droughts are a preview of a warmer future world.

USGS science for a changing world logo
March 21, 2016

The U.S. Geological Survey is playing a role in providing the science being used by agencies to manage the habitat for two threatened California fish species – the Santa Ana Sucker and the Arroyo Chub. Both species, which live in the Santa Ana River Watershed, are of special interest to local, state and federal agencies desiring to protect the fishes’ fragile ecosystem.

USGS science for a changing world logo
March 17, 2016

Scientists have traced the history of lead and mercury contamination in tidal wetlands of the Sacramento-San Joaquin Delta, according to a new U.S. Geological Survey article published in Science of the Total Environment.

Image: High Water Measurements at USGS Site 11059300
March 4, 2016

El Niño is a phenomenon that occurs when unusually warm ocean water piles up along the equatorial west coast of South America. When this phenomenon develops, it affects weather patterns around the globe, including the winter weather along the west coast of North America. This unusual pattern of sea surface temperatures occurs in irregular cycles about three to seven years apart.

High-resolution imaging spectroscopy of the Bay-Delta
February 25, 2016

To demonstrate the potential of using remote sensing to monitor water quality across broad areas, U.S Geological Survey and NASA scientists teamed up for the simultaneous collection of water quality measurements from the air and in the water. 

CalVO's Stuart Wilkinson skis out to a remote seismic instrument in...
February 24, 2016

Earthquakes rocked residents near the towns of Mammoth Lakes and Big Pine in eastern California this month, including a magnitude 3.74 and 3.44 on February 15 near Mammoth Lakes and another magnitude 4.8 near Big Pine on February 16.

Landsat image shows the marine stratus and stratocumulus cloud layer that moved into the San Francisco Bay-Delta
February 10, 2016

A new series of maps of fog and low clouds covering the northern and central California coasts reveals daytime and nighttime patterns with a level of detail never previously mapped. U.S. Geological Survey scientists used new analyses of satellite images to understand the dynamics of fog. 

USGS
January 1, 2016

We are pleased to announce the Spanish translation of our recently published CalVO Fact Sheet The California Volcano Observatory – Monitoring the State's Restless Volcanoes.

Long Valley Caldera Range Front Fault Diagram...
December 22, 2015

The shaking hazard posed by earthquakes on range-front faults near the town of Mammoth Lakes, CA is lower than previously estimated.

USGS science for a changing world logo
December 10, 2015

CORVALLIS, Ore. – Northern spotted owl populations are declining in all parts of their range in the Pacific Northwest, according to research published in The Condor. Based on data from 11 study areas across Washington, Oregon and northern California, a rangewide decline of nearly 4 percent per year was estimated from 1985 to 2013.