Regions L2 Landing Page Tabs

Filter Total Items: 612
Year Published: 2005

Napa-Sonoma marshes pond 3, hydrologic and biotic changes in a salt pond following breaching

Athearn, N.D.; Goodenough, K.; Takekawa, John Y.; Miles, A.K.; Saiki, M.K.; Spring, S.; Mejia, F.; Shellenbarger, G.G.; Schoellhamer, D.H.
Attribution: Pacific

Year Published: 2005

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: 2004

Moon, Edward; Shouse, Michelle K.; Parcheso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Cain, Daniel J.; Hornberger, Michelle I.
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: 2004; 2005; OFR; 2005-1279; Moon, Edward; Shouse, Michelle K.; Parchaso, Francis; Thompson, Janet K.; Luoma, Samuel N.; Cain Daniel J.; Hornberger, Michelle I.

Year Published: 2005

River chemistry as a monitor of Yosemite Park mountain hydroclimates

High-frequency, high-altitude measurements of water chemistry provide insights into processes relating to the hydrology, climate, and geochemistry of mountain catchments. When such observations are combined with stream stage, temperature, snow, weather, and other surface hydroclimate measurements, they are particularly useful in allowing...

Peterson, David; Smith, Richard; Hager, Stephen; Hicke, Jeffrey A.; Dettinger, Michael; Huber, King

Year Published: 2005

Snowmelt discharge characteristics Sierra Nevada, California

Alpine snow is an important water resource in California and the western U.S. Three major features of alpine snowmelt are the spring pulse (the first surge in snowmelt-driven river discharge in spring), maximum snowmelt discharge, and base flow (low river discharge supported by groundwater in fall). A long term data set of hydrologic measurements...

Peterson, David; Smith, Richard; Stewart, Iris; Knowles, Noah; Soulard, Chris; Hager, Stephen
Attribution: Pacific
Snowmelt discharge characteristics Sierra Nevada, California; 2005; SIR; 2005-5056; Peterson, David; Smith, Richard; Stewart, Iris; Knowles, Noah; Soulard, Chris; Hager, Stephen

Year Published: 2005

Recent changes toward earlier springs---early signs of climate warming in western North America

Cayan, D.; Dettinger, M.; Stewart, I.; Knowles, N.
Attribution: Pacific

Year Published: 2005

From climate-change spaghetti to climate-change distributions for 21st Century California

The uncertainties associated with climate-change projections for California are unlikely to disappear any time soon, and yet important long-term decisions will be needed to accommodate those potential changes. Projection uncertainties have typically been addressed by analysis of a few scenarios, chosen based on availability or to capture the...

Dettinger, M.D.

Year Published: 2005

Heat wave brings an unprecedented red tide to San Francisco Bay

An exceptional red tide in San Francisco Bay was observed on 8 September 2004. The red tide had chlorophyll concentrations approaching 200 mg/m3 (Figure 1) in red/purple surface streaks containing high abundances of the dinoflagellate Akashiwo sanguinea. Red tides and harmful algal blooms (HABs) are common features of coastal...

Cloern, James E.; Schraga, Tara S.; Lopez, Cary B.

Year Published: 2005

Summary of suspended-sediment concentration data, San Francisco Bay, California, Water Year 2003

Suspended-sediment concentration data were collected in San Francisco Bay during water year 2003 (October 1, 2002-September 30, 2003). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, three sites in San Pablo Bay, one site in Central San Francisco Bay, and three sites in South San...

Buchanan, Paul A.; Ganju, Neil K.
Attribution: Pacific
Summary of suspended-sediment concentration data, San Francisco Bay, California, Water Year 2003; 2005; DS; 113; Buchanan, Paul A.; Ganju, Neil K.

Year Published: 2005

A long-term (50 yr) historical perspective on flood-generating winter storms in the American River basin

No abstract available.

Dettinger, M.D.
Attribution: Pacific

Year Published: 2005

Bay sediment budget: Sediment accounting 101

Comparison of a budget developed for 1955-1990 with a budget developed for 1995- 2002 showed decreasing sediment inflow and increased amounts leaving the Bay to upland disposal and sand mining, resulting in an increased rate of erosion of sediment from the Bay floor Finding a way to shift disposal from the Ocean back to the Bay could provide...

Schoellhamer, David H.; Lionberger, Megan A.; Jaffe, Bruce E.; Ganju, Neil K.; Wright, Scott A.; Shellenbarger, Gregory
Attribution: Pacific

Year Published: 2005

Climate anomalies generate an exceptional dinoflagellate bloom in San Francisco Bay

We describe a large dinoflagellate bloom, unprecedented in nearly three decades of observation, that developed in San Francisco Bay (SFB) during September 2004. SFB is highly enriched in nutrients but has low summer‐autumn algal biomass because wind stress and tidally induced bottom stress produce a well mixed and light‐limited pelagic habitat....

Cloern, J.E.; Schraga, T.S.; Lopez, C.B.; Knowles, N.; Grover, Labiosa R.; Dugdale, R.
Climate anomalies generate an exceptional dinoflagellate bloom in San Francisco Bay; 2005; Article; Journal; Geophysical Research Letters; Cloern, J. E.; Schraga, T. S.; Lopez, C. B.; Knowles, N.; Grover, Labiosa, R.; Dugdale, R.

Year Published: 2005

Detritus fuels ecosystem metabolism but not metazoan food webs in San Francisco estuary's freshwater delta

Detritus from terrestrial ecosystems is the major source of organic matter in many streams, rivers, and estuaries, yet the role of detritus in supporting pelagic food webs is debated. We examined the importance of detritus to secondary productivity in the Sacramento and San Joaquin River Delta (California, United States), a large complex of tidal...

Sobczak, W.V.; Cloern, J.E.; Jassby, A.D.; Cole, B.E.; Schraga, T.S.; Arnsberg, A.
Detritus fuels ecosystem metabolism but not metazoan food webs in San Francisco estuary's freshwater delta; 2005; Article; Journal; Estuaries; Sobczak, W. V.; Cloern, J. E.; Jassby, A. D.; Cole, B. E.; Schraga, T. S.; Arnsberg, A.

Filter Total Items: 222
October 27, 2016

PubTalk 10/2016 — Rockfalls in California's Sierra Nevada

Rock falls in California’s Sierra Nevada - Pursuing explanations for exfoliation and seemingly spontaneous fracture of rock

October 19, 2016

B-roll Sampling and Coring in San Pablo Bay

All clips show the deck of a barge in San Pablo Bay, California.

  • Clip 1 - USGS technicians lower and raise a grab sampler
  • Clips 2, 3, 4 - USGS technicians lower and raise a vibracore
  • Clip 5 - Tanker passes as USGS technicians work on anchor lines
  • Clip 6 - USGS technicians raise anchor, while another works on a vibracore tube
July 28, 2016

July Public Lecture — USGS CalVO: It's not just earthquake country!

Volcanic eruptions occur int he State about as frequently as the large San Andreas Fault Zone earthquakes. California's "watch list" volcanoes are dispersed throughout the State and future eruptions are inevitable—the likelihood of renewed volcanism is on the order of one in a few hundred to one in a few thousand annually.

With Margaret Mangan, Scientist-in-Charge,

July 24, 2016

Kīlauea Volcano, Halemaʻumaʻu Crater, Summit Vent Lava Lake (4K)

Stunning 4K aerial and ground b-roll of the Kīlauea Volcano Halemaʻumaʻu Crater Summit Vent Lava Lake taken between July 24 and July 31, 2016. 

Here is the shotlist: 
00:11 Kīlauea summit lava lake spatter, night, medium shot 
00:33 Lava lake spatter, night medium shot 
00:43 Lava lake wide shot, night, spatter on right of frame 
1:01 Wide shot,

Aerial view of a lava vent seen from a helicopter
June 16, 2016

Lava Vent Aerial over Puʻu ʻŌʻō, Hawaiʻi

Though difficult to photograph, aerial views showed that this open vent was but a small window into a large, hot cavity beneath Puʻu ʻŌʻō's northeast flank in Hawaii Inside, streams of lava from an unseen source (or sources) closer to the crater rim (visible at lower right) were cascading toward the upper left into unknown depths. This view, looking almost straight down,

June 15, 2016

Running Rivers

What inspired a USGS geologist to study how dam removal changes rivers. Profile of Amy East.

Glacier National Park
June 5, 2016

Glacier Bay National Park

View of Glacier Bay National Park from the air.

Fairweather Fault
June 5, 2016

Fairweather Fault

USGS research geologist Kate Scharer with her finger on the Fairweather Fault in southeast Alaska. The magnitude 7.8 Lituya Bay earthquake caused shaking that toppled trees along the fault, which left a break in the forest shown here.

South Crillon Glacier
June 5, 2016

South Crillon Glacier

Nearly 60 years after a magnitude 7.7 earthquake struck Lituya Bay, Alaska — leading to a tsunami that devastated the area — six U.S. Geological Survey geologists revisited the isolated region of Alaska, to pick up where their scientific predecessors left off. In this photo, members of the USGS research team pause to take in the view of South Crillon Glacier from a study

South Crillon Glacier
June 5, 2016

South Crillon Glacier

Periodic calving of ice from the snout of South Crillon Glacier.

Glacier Bay National Park
June 5, 2016

Glacier Bay National Park

Trench site along the southern Fairweather Fault, in Glacier Bay National Park, Alaska. The alluvial fan at left consists of lake, stream channel and debris flow deposits impounded by the Fairweather Fault scarp, at right.

Research and technical support provided by USGS makes a difference Some recent press releases and media advisories from the Pacific Region are highlighted below.

Filter Total Items: 60
Image: USGS Scientists Engaged in Field Work on the Aleutian Islands
January 12, 2016

New evidence for frequent large tsunamis at a remote island near Dutch Harbor, Alaska provides geological data to aid tsunami hazard preparedness efforts around the Pacific Rim. 

November 24, 2015

A new study completed by the U.S. Geological Survey, in cooperation with the Borrego Water District, will help water planners in the Borrego Valley, California better understand and manage the groundwater resources that the area relies on for drinking water, agriculture and recreation.

October 22, 2015

Joint Venture Silicon Valley and the U.S. Geological Survey today jointly announced a partnership to address regional challenges from natural hazards, climate and land use change, and continued availability of clean air and water resources.

October 14, 2015

MENLO PARK, Calif. — U.S. Geological Survey employees in Menlo Park, Calif. will participate in an earthquake safety drill, and test their emergency response plan as part of the Great ShakeOut on Oct. 15, an annual day of action to practice how to protect yourself from an earthquake.

Fumarole on Kīlauea Volcano, Hawaiʻi. Elemental sulfur vapor escaping from the fumarole has cooled to form yellow-colored crysta
October 5, 2015

Fumaroles are openings in the earth’s surface that emit steam and volcanic gases, such as sulfur dioxide and carbon dioxide. They can occur as holes, cracks, or fissures near active volcanoes or in areas where magma has risen into the earth’s crust without erupting. A fumarole can vent for centuries or quickly go extinct, depending on the longevity of its heat source.

October 1, 2015

This year, groundwater levels in many wells in California’s Central Valley are at or below historical low levels. In addition, from 2007 through 2015, land subsidence that correlates to areas with large groundwater level declines has strongly increased in two large agricultural areas near the towns of El Nido and Pixley, according to a new article by the U.S. Geological Survey.

Image:  Black-footed Albatross with Chick
September 23, 2015

Islands used by tropical seabirds are highly vulnerable to sea level rise according to a new study released today.

Image: Aerial View of Mauna Loa Volcano, Hawaii
September 17, 2015

Scientists at the U.S. Geological Survey Hawaiian Volcano Observatory have elevated the Volcano Alert Level for Mauna Loa from NORMAL to ADVISORY. This change in status indicates that the volcano is showing signs of unrest that are above known background levels, but it does not mean that a Mauna Loa eruption is imminent or certain.

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.

July 27, 2015

One winter's night in the year 1700, a mysterious tsunami flooded fields and washed away houses in Japan. It arrived without the warning that a nearby earthquake usually provides.

Map of sediment thickness in state waters offshore of San Francisco.
May 21, 2015

Three new sets of maps detail the offshore bathymetry, habitats, geology and submarine environment of the seafloor off the coast of San Francisco, Drakes Bay, and Tomales Point.

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.

Filter Total Items: 76