The Southern California Twin Register at the University of Southern California: III

PubMed Central

Baker, Laura A.; Tuvblad, Catherine; Wang, Pan; Gomez, Karina; Bezdjian, Serena; Niv, Sharon; Raine, Adrian

2013-01-01

The Southern California Twin Register at the University of Southern California (USC) was initiated in 1984 and continues to provide an important resource for studies investigating genetic and environmental influences on human behavior. This article provides an update on the current register and its potential for future twin studies using recruitment through school district databases and voter records. An overview is also provided for an ongoing longitudinal twin study investigating the development of externalizing psychopathology from childhood to young adulthood, the USC Study of Risk Factors for Antisocial Behavior. Characteristics of the twins and their families are presented, including recruitment and participation rates, as well as attrition analyses and a summary of key findings to date. PMID:23394193

1991 Southern California origin-destination survey : summary findings

DOT National Transportation Integrated Search

1993-02-01

This report presents the findings from the 1991 Southern California Origin-Destination Survey. The survey was coordinated and managed by the Southern California Association of Governments (SCAG) for the following five agencies representing their resp...

Lithospheric thinning beneath rifted regions of Southern California.

PubMed

Lekic, Vedran; French, Scott W; Fischer, Karen M

2011-11-11

The stretching and break-up of tectonic plates by rifting control the evolution of continents and oceans, but the processes by which lithosphere deforms and accommodates strain during rifting remain enigmatic. Using scattering of teleseismic shear waves beneath rifted zones and adjacent areas in Southern California, we resolve the lithosphere-asthenosphere boundary and lithospheric thickness variations to directly constrain this deformation. Substantial and laterally abrupt lithospheric thinning beneath rifted regions suggests efficient strain localization. In the Salton Trough, either the mantle lithosphere has experienced more thinning than the crust, or large volumes of new lithosphere have been created. Lack of a systematic offset between surface and deep lithospheric deformation rules out simple shear along throughgoing unidirectional shallow-dipping shear zones, but is consistent with symmetric extension of the lithosphere.

Alluvial Scrub Vegetation in Coastal Southern California

Treesearch

Ted L. Hanes; Richard D. Friesen; Kathy Keane

1989-01-01

Certain floodplain systems in southern California sustain a unique scrub vegetation rather than riparian woodlands due to a lack of perennial water. Alluvial scrub occurs on outwash fans and riverine deposits along the coastal side of major mountains of southern California. This vegetation type is adapted to severe floods and erosion, nutrient-poor substrates, and the...

Southern California Edison PDF

EPA Pesticide Factsheets

This Southern California Edison report describes an evaluation of SCE’s Retail Appliance Recycling Program (Retail ARP) trial that was initiated in late October 2010 and completed in September of 2011.

50 CFR 226.210 - Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California Coasts Coho Salmon (Oncorhynchus kisutch). 226.210... Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California Coasts Coho Salmon...

50 CFR 226.210 - Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California Coasts Coho Salmon (Oncorhynchus kisutch). 226.210... Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California Coasts Coho Salmon...

Southern California Earthquake Center Geologic Vertical Motion Database

NASA Astrophysics Data System (ADS)

Niemi, Nathan A.; Oskin, Michael; Rockwell, Thomas K.

2008-07-01

The Southern California Earthquake Center Geologic Vertical Motion Database (VMDB) integrates disparate sources of geologic uplift and subsidence data at 104- to 106-year time scales into a single resource for investigations of crustal deformation in southern California. Over 1800 vertical deformation rate data points in southern California and northern Baja California populate the database. Four mature data sets are now represented: marine terraces, incised river terraces, thermochronologic ages, and stratigraphic surfaces. An innovative architecture and interface of the VMDB exposes distinct data sets and reference frames, permitting user exploration of this complex data set and allowing user control over the assumptions applied to convert geologic and geochronologic information into absolute uplift rates. Online exploration and download tools are available through all common web browsers, allowing the distribution of vertical motion results as HTML tables, tab-delimited GIS-compatible text files, or via a map interface through the Google Maps™ web service. The VMDB represents a mature product for research of fault activity and elastic deformation of southern California.

Miocene rapakivi granites in the southern Death Valley region, California, USA

USGS Publications Warehouse

Calzia, J.P.; Ramo, O.T.

2005-01-01

Rapakivi granites in the southern Death Valley region, California, include the 12.4-Ma granite of Kingston Peak, the ca. 10.6-Ma Little Chief stock, and the 9.8-Ma Shoshone pluton. All of these granitic rocks are texturally zoned from a porphyritic rim facies, characterized by rapakivi textures and miarolitic cavities, to an equigranular aplite core. These granites crystallized from anhydrous and peraluminous to metaluminous magmas that were more oxidized and less alkalic than type rapakivi granites from southern Finland. Chemical and isotope (Nd-Sr-Pb) data suggest that rapakivi granites of the southern Death Valley region were derived by partial melting of lower crustal rocks (possibly including Mesozoic plutonic component) with some mantle input as well; they were emplaced at shallow crustal levels (4 km) in an actively extending orogen.

Miocene rapakivi granites in the southern Death Valley region, California, USA

USGS Publications Warehouse

Calzia, James P.; Ramo, O.T.

2005-01-01

Rapakivi granites in the southern Death Valley region, California, include the 12.4-Ma granite of Kingston Peak, the ca. 10.6-Ma Little Chief stock, and the 9.8-Ma Shoshone pluton. All of these granitic rocks are texturally zoned from a porphyritic rim facies, characterized by rapakivi textures and miarolitic cavities, to an equigranular aplite core. These granites crystallized from anhydrous and peraluminous to metaluminous magmas that were more oxidized and less alkalic than type rapakivi granites from southern Finland. Chemical and isotope (Nd–Sr–Pb) data suggest that rapakivi granites of the southern Death Valley region were derived by partial melting of lower crustal rocks (possibly including Mesozoic plutonic component) with some mantle input as well; they were emplaced at shallow crustal levels (4 km) in an actively extending orogen.

Isotopes and ages in the northern Peninsular Ranges batholith, southern California

USGS Publications Warehouse

Kistler, Ronald W.; Wooden, Joseph L.; Morton, Douglas M.

2003-01-01

Strontium, oxygen and lead isotopic and rubidium-strontium geochronologic studies have been completed on Cretaceous and Jurassic (?) granitic rock samples from the northern Peninsular Ranges batholith in southern California. Many of these samples were collected systematically and studied chemically by A. K. Baird and colleagues (Baird and others, 1979). The distribution of these granitic rocks is shown in the Santa Ana, Perris, and San Jacinto Blocks, bounded by the Malibu Coast-Cucamonga, Banning, and San Andreas fault zones, and the Pacific Ocean on the map of the Peninsular Ranges batholith and surrounding area, southern California. The granitic rock names are by Baird and Miesch (1984) who used a modal mineral classification that Bateman and others (1963) used for granitic rocks in the Sierra Nevada batholith. In this classification, granitic rocks have at least 10% quartz. Boundaries between rock types are in terms of the ratio of alkali-feldspar to total feldspar: quartz diorite, 0-10%; granodiorite, 10-35%; quartz monzonite 35-65%; granite >65%. Gabbros have 0-10% quartz. Data for samples investigated are giv in three tables: samples, longitude, latitude, specific gravity and rock type (Table 1); rubidium and strontium data for granitic rocks of the northern Peninsular Ranges batholith, southern California (Table 2); U, Th, Pb concentrations, Pb and Sr initial isotopic compositions, and δ18O permil values for granitic rocks of the northern Peninsular Ranges batholith (table 3).

New cooperative seismograph networks established in southern California

USGS Publications Warehouse

Hill, D.P.

1974-01-01

Southern California has more active faults located close to large, urban population centers than any other region in the United States. Reduction of risk to life and property posed by potential earthquakes along these active faults is a primary motivation for a cooperative earthquake research program between the U.S Geological Survey and major universities in Southern California. 

An extirpated lineage of a threatened frog species resurfaces in southern California

USGS Publications Warehouse

Backlin, Adam R.; Richmond, Jonathan Q.; Gallegos, Elizabeth; Christensen, Clinton K.; Fisher, Robert N.

2017-01-01

Southern California has experienced widespread amphibian declines since the 1960s. One species, the Vulnerable California red-legged frog Rana draytonii, is now considered to be extirpated from most of southern California. In February 2017 a population of R. draytonii was discovered in the southern foothills of the San Bernardino Mountains of Riverside County, California, near the edge of the species’ historical distribution. This population belongs to an mtDNA lineage that was presumed to be extirpated within the USA but is still extant in Baja California, Mexico. This discovery increases the potential for future, evolutionarily informed translocations within the southern portion of this species’ range in California.

Evidence for coseismic subsidence events in a southern California coastal saltmarsh

USGS Publications Warehouse

Leeper, Robert; Rhodes, Brady P.; Kirby, Matthew E.; Scharer, Katherine M.; Carlin, Joseph A.; Hemphill-Haley, Eileen; Avnaim-Katav, Simona; MacDonald, Glen M.; Starratt, Scott W.; Aranda, Angela

2017-01-01

Paleoenvironmental records from a southern California coastal saltmarsh reveal evidence for repeated late Holocene coseismic subsidence events. Field analysis of sediment gouge cores established discrete lithostratigraphic units extend across the wetland. Detailed sediment analyses reveal abrupt changes in lithology, percent total organic matter, grain size, and magnetic susceptibility. Microfossil analyses indicate that predominantly freshwater deposits bury relic intertidal deposits at three distinct depths. Radiocarbon dating indicates that the three burial events occurred in the last 2000 calendar years. Two of the three events are contemporaneous with large-magnitude paleoearthquakes along the Newport-Inglewood/Rose Canyon fault system. From these data, we infer that during large magnitude earthquakes a step-over along the fault zone results in the vertical displacement of an approximately 5-km2 area that is consistent with the footprint of an estuary identified in pre-development maps. These findings provide insight on the evolution of the saltmarsh, coseismic deformation and earthquake recurrence in a wide area of southern California, and sensitive habitat already threatened by eustatic sea level rise.

AmeriFlux US-SCd Southern California Climate Gradient - Sonoran Desert

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Mike

This is the AmeriFlux version of the carbon flux data for the site US-SCd Southern California Climate Gradient - Sonoran Desert. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of six Southern California Climate Gradient flux towers operated along an elevation gradient (sites are US-SCg, US-SCs, US-SCf, US-SCw, US-SCc, US-SCd). This site is a low desert site in Southern California's rain shadow; the climate is extremely dry and hot. The site has experience repeated droughts, with negligible rainfall during several years of the record.

Informal optics education and outreach programs in Southern California

NASA Astrophysics Data System (ADS)

Silberman, Donn M.; Cartland, Robert; Monacelli, Brian; Whitmore, Desire

2010-08-01

Over the past decade, Southern California has seen informal optics education and outreach programs grow substantially, mainly due to efforts from members of the Optical Society of Southern California (OSSC) and more recently the Optical Society of America, UC Irvine, Student Chapter. Also, the Optics Institute of Southern California (OISC) has served as a focal point for many of these programs, as an independent organization working closely with society members and other partners. This paper provides an update of these programs, including a new OSSC website that provides a new platform for significantly expanding the member participation efforts.

High-resolution seismic-reflection data offshore of Dana Point, southern California borderland

USGS Publications Warehouse

Sliter, Ray W.; Ryan, Holly F.; Triezenberg, Peter J.

2010-01-01

The U.S. Geological Survey collected high-resolution shallow seismic-reflection profiles in September 2006 in the offshore area between Dana Point and San Mateo Point in southern Orange and northern San Diego Counties, California. Reflection profiles were located to image folds and reverse faults associated with the San Mateo fault zone and high-angle strike-slip faults near the shelf break (the Newport-Inglewood fault zone) and at the base of the slope. Interpretations of these data were used to update the USGS Quaternary fault database and in shaking hazard models for the State of California developed by the Working Group for California Earthquake Probabilities. This cruise was funded by the U.S. Geological Survey Coastal and Marine Catastrophic Hazards project. Seismic-reflection data were acquired aboard the R/V Sea Explorer, which is operated by the Ocean Institute at Dana Point. A SIG ELC820 minisparker seismic source and a SIG single-channel streamer were used. More than 420 km of seismic-reflection data were collected. This report includes maps of the seismic-survey sections, linked to Google Earth? software, and digital data files showing images of each transect in SEG-Y, JPEG, and TIFF formats.

Implications of Deoxygenation and Acidification for Deep Sea Urchins in Southern California

NASA Astrophysics Data System (ADS)

Sato, Kirk Nicholas Suda

Implications of multiple climate drivers for sea urchins were investigated across a spectrum of biological organization ranging from the urchin guild scale, to individual life history traits, to the geochemistry, material properties and porosity of sea urchin calcium carbonate skeletal tests. Using pink fragile sea urchins (Strongylocentrotus fragilis) on the southern California upwelling margin as a model species, links between biological traits and environmental parameters in nature across multiple spatial and temporal scales revealed correlations with dissolved oxygen (DO), pH, and temperature. Temporal trends in sea urchin populations assessed from trawl surveys conducted in southern California over the last 20 years (1994-2013) revealed changes in deep-sea urchin densities and depth distributions that coincide with trends in DO and pH on multidecadal and interdecadal (El Nino Southern Oscillation) time scales. The shallower urchin species ( Lytechinus pictus) decreased in density in the upper 200 m by 80%, and the deeper S. fragilis increased in density by ˜300%, providing the first evidence of habitat compression and expansion in sea urchin populations associated with secular and interdecadal variability in DO and pH. In this context, marketable food quality properties of the roe were compared between S. fragilis and the currently fished California red urchin, Mesocentrotus franciscanus, to assess the feasibility of developing a climate change-tolerant future S. fragilis trap fishery. Although roe color, texture, and resilience were similar between the two species, smaller and softer S. fragilis roe suggest it may only supplement, but not replace M. franciscanus in future fisheries. In comparisons across natural margin depth and climate gradients from 100-1100 m, S. fragilis exhibited reduced gonad production, smaller, weaker and more porous calcified tests in the Oxygen Minimum Zone (DO < 22 mumol kg-1) and pH Minimum Zone (in situ pHTotal <7.57) than those

Lifelong Information Literacy in Southern California. The College Connection

ERIC Educational Resources Information Center

Wallace, Amy

2007-01-01

In this article, the author highlights collaborative information literacy initiatives of four higher education institutions in Southern California--California State University-Channel Islands, California State University-Los Angeles, University of California-Irvine, and University of California-Los Angeles. Librarians from these institutions serve…

The offshore Palos Verdes fault zone near San Pedro, Southern California

USGS Publications Warehouse

Fisher, M.A.; Normark, W.R.; Langenheim, V.E.; Calvert, A.J.; Sliter, R.

2004-01-01

High-resolution seismic-reflection data are combined with a variety of other geophysical and geological data to interpret the offshore structure and earthquake hazards of the San Pedro shelf, near Los Angeles, California. Prominent structures investigated include the Wilmington graben, the Palos Verdes fault zone, various faults below the west part of the San Pedro shelf and slope, and the deep-water San Pedro basin. The structure of the Palos Verdes fault zone changes markedly along strike southeastward across the San Pedro shelf and slope. Under the north part of the shelf, this fault zone includes several strands, with the main strand dipping west. Under the slope, the main fault strands exhibit normal separation and mostly dip east. To the southeast near Lasuen Knoll, the Palos Verdes fault zone locally is low angle, but elsewhere near this knoll, the fault dips steeply. Fresh seafloor scarps near Lasuen Knoll indicate recent fault movement. We explain the observed structural variation along the Palos Verdes fault zone as the result of changes in strike and fault geometry along a master right-lateral strike-slip fault at depth. Complicated movement along this deep fault zone is suggested by the possible wave-cut terraces on Lasuen Knoll, which indicate subaerial exposure during the last sea level lowstand and subsequent subsidence of the knoll. Modeling of aeromagnetic data indicates a large magnetic body under the west part of the San Pedro shelf and upper slope. We interpret this body to be thick basalt of probable Miocene age. This basalt mass appears to have affected the pattern of rock deformation, perhaps because the basalt was more competent during deformation than the sedimentary rocks that encased the basalt. West of the Palos Verdes fault zone, other northwest-striking faults deform the outer shelf and slope. Evidence for recent movement along these faults is equivocal, because we lack age dates on deformed or offset sediment.

Geoloogic slip on offshore San Clemente fault, Southern California, understated in GPS data

NASA Astrophysics Data System (ADS)

Legg, M. R.

2005-12-01

The San Clemente fault offshore southern California exhibits prominent geomorphic evidence of major late Quaternary right-slip. Like the San Andreas fault, where modern Pacific-North America transform motion is focused, the San Clemente fault stretches more than 700 km along the continental margin with a well-defined principal displacement zone (PDZ). Lateral offset is generally concentrated in a zone less than about 1 km wide, and linear seafloor fault scarps cutting across active submarine fans and basin-filling turbidites demonstrate Holocene activity. Dextral offset of middle Miocene circular crater structures suggest as much as 60 km of Neogene and younger displacement. Offset submarine fan depositional features suggest a rate of about 4-7 mm/yr of late Quaternary slip. Nearly 75 years of seismograph recording in southern California registered at least three moderate (M~6) earthquakes, activity which exceeds that of the Elsinore fault with a similar measured slip rate. Geodetic data based only on a few decades of GPS observations have been interpreted to show less than 1 mm/yr right-slip on the San Clemente fault, whereas larger rates, of about 5-10 mm/yr are described in the Inner Borderland between Catalina Island and the coast. Extrapolations of data from GPS stations on the Pacific Plate offshore Baja California also suggest larger rates west of San Clemente Island. Because there are few offshore locations (islands) for GPS observations, and San Clemente Island is likely within the broader zone of deformation of its namesake fault, these data miss the full slip rate. Seafloor observations from submersible discovered youthful fault scarps in turbidite muds that are inferred to represent large prehistoric earthquakes, (M~7). The potential for large offshore earthquakes, with tsunami generation that would affect the heavily populated adjacent coastal areas underscores the importance of resolving the slip rate and quantifying the hazard potential.

Evaluation of road expansion and connectivity mitigation for wildlife in southern California

USGS Publications Warehouse

Alonso, Robert S.; Lyren, Lisa M.; Boydston, Erin E.; Haas, Christopher D.; Crooks, Kevin R.

2014-01-01

We designed a remote-camera survey to study how the expansion of California State Route 71 (CA-71) and implementation of connectivity mitigation affected the use of underpasses by large mammals in southern California. Based on detections by cameras, the use of underpasses by bobcats (Lynx rufus) was higher within the area of expansion and mitigation after construction than before, but there was no difference in use of underpasses in the impact zone compared to the control zone before or after construction. Use of underpasses by coyotes (Canis latrans) was higher in the control zone than in the impact zone, but there was no difference in use before and after construction. Small numbers of detections of mule deer (Odocoileus hemionus) at only a few underpasses precluded comparison between control and impact zones. However, a comparison of use before and after construction revealed that use of underpasses by mule deer was slightly higher post-construction. We cannot fully attribute increased detections post-construction to mitigative efforts, because other factors, such as availability of habitat, urbanization, or demography, also may have influenced use of underpasses along CA-71. Nonetheless, even with the expansion of the freeway and subsequent increase in volume of traffic, mitigative structures along CA-71 did allow for continued movement and, hence, connectivity across the roadway for large mammals.

NREL + Southern California Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berdahl, Sonja E

2017-10-09

NREL and Southern California Gas Company are evaluating a new 'power-to-gas' approach - one that produces methane through a biological pathway and uses the expansive natural gas infrastructure to store it. This approach has the potential to change how the power industry approaches renewable generation and energy storage.

Burn Scars Across Southern California

NASA Image and Video Library

2003-11-26

Brush fires consumed nearly 750,000 acres across Southern California between October 21 and November 18, 2003. Burn scars and vegetation changes wrought by the fires are illustrated in these false-color images from NASA Terra spacecraft.

Is the Vincent fault in southern California the Laramide subduction zone megathrust?

NASA Astrophysics Data System (ADS)

Xia, H.; Platt, J. P.

2016-12-01

The Vincent fault (VF) in the San Gabriel Mountains, southern California separates a Meso-Proterozoic gneiss complex and Mesozoic granitoid rocks in the upper plate from the ocean-affiliated Late Cretaceous Pelona schist in the lower plate, and it has been widely interpreted as the original Laramide subduction megathrust. A 500 to 1000 m thick mylonite zone, consisting of a low-stress (LS) section at the bottom, a high-stress (HS) section at the top, and a weakly deformed section in between, is developed above the VF. Our kinematic, thermobarometric and geochronological analysis of the mylonite zone indicates that the VF is a normal fault. Shear sense indicators including asymmetric porphyroblasts, quartz new grain fabric, mineral fish, and quartz CPO from the HS and the LS sections exhibit a top-to-SE sense of shear on the SW-dipping mylonitic foliation, which is contrary to what one would expect for the Laramide subduction megathrust. A few samples from the LS section were overprinted by HS microstructure, implying that the LS mylonites predate the HS mylonites. TitaniQ thermometer and Si-in-muscovite barometer show that the P-T conditions are 389 ± 6 °C, 5 kbar for the LS mylonites and 329 ± 6 °C, 2.4 kbar for HS mylonites. Considering the temporal sequence of HS and LS mylonites, they are likely to be formed during exhumation. A comparison with the lower plate leads to the same conclusion. The top 80-100 m of the Pelona schist underneath the VF is folded and also mylonitized, forming the Narrows synform and S3 simultaneously. Our previous study found that S3 of the Pelona schist has a top-to-SE sense of shear and similar P-T conditions as the LS mylonite in the upper plate, so S3 of the Pelona schist is likely to be formed together with the LS mylonites in the upper plate. While mylonitization of Pelona schist (S3) overprinted both the subduction-related S1 fabric and the return-flow-related S2 fabric, it is reasonable to argue that the mylonite zone above

Stormwater plume detection by MODIS imagery in the southern California coastal ocean

USGS Publications Warehouse

Nezlin, N.P.; DiGiacomo, P.M.; Diehl, D.W.; Jones, B.H.; Johnson, S.C.; Mengel, M.J.; Reifel, K.M.; Warrick, J.A.; Wang, M.

2008-01-01

Stormwater plumes in the southern California coastal ocean were detected by MODIS-Aqua satellite imagery and compared to ship-based data on surface salinity and fecal indicator bacterial (FIB) counts collected during the Bight'03 Regional Water Quality Program surveys in February-March of 2004 and 2005. MODIS imagery was processed using a combined near-infrared/shortwave-infrared (NIR-SWIR) atmospheric correction method, which substantially improved normalized water-leaving radiation (nLw) optical spectra in coastal waters with high turbidity. Plumes were detected using a minimum-distance supervised classification method based on nLw spectra averaged within the training areas, defined as circular zones of 1.5-5.0-km radii around field stations with a surface salinity of S 33.0 ('ocean'). The plume optical signatures (i.e., the nLw differences between 'plume' and 'ocean') were most evident during the first 2 days after the rainstorms. To assess the accuracy of plume detection, stations were classified into 'plume' and 'ocean' using two criteria: (1) 'plume' included the stations with salinity below a certain threshold estimated from the maximum accuracy of plume detection; and (2) FIB counts in 'plume' exceeded the California State Water Board standards. The salinity threshold between 'plume' and 'ocean' was estimated as 32.2. The total accuracy of plume detection in terms of surface salinity was not high (68% on average), seemingly because of imperfect correlation between plume salinity and ocean color. The accuracy of plume detection in terms of FIB exceedances was even lower (64% on average), resulting from low correlation between ocean color and bacterial contamination. Nevertheless, satellite imagery was shown to be a useful tool for the estimation of the extent of potentially polluted plumes, which was hardly achievable by direct sampling methods (in particular, because the grids of ship-based stations covered only small parts of the plumes detected via

Stormwater plume detection by MODIS imagery in the southern California coastal ocean

NASA Astrophysics Data System (ADS)

Nezlin, Nikolay P.; DiGiacomo, Paul M.; Diehl, Dario W.; Jones, Burton H.; Johnson, Scott C.; Mengel, Michael J.; Reifel, Kristen M.; Warrick, Jonathan A.; Wang, Menghua

2008-10-01

Stormwater plumes in the southern California coastal ocean were detected by MODIS-Aqua satellite imagery and compared to ship-based data on surface salinity and fecal indicator bacterial (FIB) counts collected during the Bight'03 Regional Water Quality Program surveys in February-March of 2004 and 2005. MODIS imagery was processed using a combined near-infrared/shortwave-infrared (NIR-SWIR) atmospheric correction method, which substantially improved normalized water-leaving radiation (nLw) optical spectra in coastal waters with high turbidity. Plumes were detected using a minimum-distance supervised classification method based on nLw spectra averaged within the training areas, defined as circular zones of 1.5-5.0-km radii around field stations with a surface salinity of S < 32.0 ("plume") and S > 33.0 ("ocean"). The plume optical signatures (i.e., the nLw differences between "plume" and "ocean") were most evident during the first 2 days after the rainstorms. To assess the accuracy of plume detection, stations were classified into "plume" and "ocean" using two criteria: (1) "plume" included the stations with salinity below a certain threshold estimated from the maximum accuracy of plume detection; and (2) FIB counts in "plume" exceeded the California State Water Board standards. The salinity threshold between "plume" and "ocean" was estimated as 32.2. The total accuracy of plume detection in terms of surface salinity was not high (68% on average), seemingly because of imperfect correlation between plume salinity and ocean color. The accuracy of plume detection in terms of FIB exceedances was even lower (64% on average), resulting from low correlation between ocean color and bacterial contamination. Nevertheless, satellite imagery was shown to be a useful tool for the estimation of the extent of potentially polluted plumes, which was hardly achievable by direct sampling methods (in particular, because the grids of ship-based stations covered only small parts of the

Characterizing potentially induced earthquake rate changes in the Brawley Seismic Zone, southern California

USGS Publications Warehouse

Llenos, Andrea L.; Michael, Andrew J.

2016-01-01

The Brawley seismic zone (BSZ), in the Salton trough of southern California, has a history of earthquake swarms and geothermal energy exploitation. Some earthquake rate changes may have been induced by fluid extraction and injection activity at local geothermal fields, particularly at the North Brawley Geothermal Field (NBGF) and at the Salton Sea Geothermal Field (SSGF). We explore this issue by examining earthquake rate changes and interevent distance distributions in these fields. In Oklahoma and Arkansas, where considerable wastewater injection occurs, increases in background seismicity rate and aftershock productivity and decreases in interevent distance were indicative of fluid‐injection‐induced seismicity. Here, we test if similar changes occur that may be associated with fluid injection and extraction in geothermal areas. We use stochastic epidemic‐type aftershock sequence models to detect changes in the underlying seismogenic processes, shown by statistically significant changes in the model parameters. The most robust model changes in the SSGF roughly occur when large changes in net fluid production occur, but a similar correlation is not seen in the NBGF. Also, although both background seismicity rate and aftershock productivity increased for fluid‐injection‐induced earthquake rate changes in Oklahoma and Arkansas, the background rate increases significantly in the BSZ only, roughly corresponding with net fluid production rate increases. Moreover, in both fields the interevent spacing does not change significantly during active energy projects. This suggests that, although geothermal field activities in a tectonically active region may not significantly change the physics of earthquake interactions, earthquake rates may still be driven by fluid injection or extraction rates, particularly in the SSGF.

Seafloor bathymetry and gravity from the ALBACORE marine seismic experiment offshore southern California

NASA Astrophysics Data System (ADS)

Shintaku, N.; Weeraratne, D. S.; Kohler, M. D.

2010-12-01

Although the North America side of the plate boundary surrounding the southern California San Andreas fault region is well studied and instrumented, the Pacific side of this active tectonic boundary is poorly understood. In order to better understand this complex plate boundary offshore, its microplate structures, deformation, and the California Borderland formation, we have recently conducted the first stage of a marine seismic experiment (ALBACORE - Asthenospheric and Lithospheric Broadband Architecture from the California Offshore Region Experiment) deploying 34 ocean bottom seismometers offshore southern California in August 2010. We present preliminary data consisting of seafloor bathymetry and free air gravity collected from this experiment. We present high-resolution maps of bathymetry and gravity from the ALBACORE experiment compiled with previous ship track data obtained from the NGDC (National Geophysical Data Center) and the USGS. We use gravity data from Smith and Sandwell and study correlations with ship track bathymetry data for the features described below. We observe new seafloor geomorphological features far offshore and within the Borderland. Steep canyon walls which line the edges of the Murray fracture zone with possible volcanic flows along the canyon floor were mapped by multibeam bathymetry for the first time. Deep crevices juxtaposed with high edifices of intensely deformed plateaus indicate high strain deformation along the arcuate boundary of the Arguello microplate. Small volcanic seamounts are mapped which straddle the Ferrelo fault (Outer Borderland) and San Pedro fault (Inner Borderland), and appear to exhibit fracture and fault displacement of a portion of the volcanic centers in a left-lateral sense. A large landslide is also imaged extending approximately 6 miles in length and 3 miles in width in the Santa Cruz basin directly south of Santa Rosa Island. Deformation associated with capture of Arguello and Patton microplates by the

Crustal-scale tilting of the central Salton block, southern California

USGS Publications Warehouse

Dorsey, Rebecca; Langenheim, Victoria

2015-01-01

The southern San Andreas fault system (California, USA) provides an excellent natural laboratory for studying the controls on vertical crustal motions related to strike-slip deformation. Here we present geologic, geomorphic, and gravity data that provide evidence for active northeastward tilting of the Santa Rosa Mountains and southern Coachella Valley about a horizontal axis oriented parallel to the San Jacinto and San Andreas faults. The Santa Rosa fault, a strand of the San Jacinto fault zone, is a large southwest-dipping normal fault on the west flank of the Santa Rosa Mountains that displays well-developed triangular facets, narrow footwall canyons, and steep hanging-wall alluvial fans. Geologic and geomorphic data reveal ongoing footwall uplift in the southern Santa Rosa Mountains, and gravity data suggest total vertical separation of ∼5.0–6.5 km from the range crest to the base of the Clark Valley basin. The northeast side of the Santa Rosa Mountains has a gentler topographic gradient, large alluvial fans, no major active faults, and tilted inactive late Pleistocene fan surfaces that are deeply incised by modern upper fan channels. Sediments beneath the Coachella Valley thicken gradually northeast to a depth of ∼4–5 km at an abrupt boundary at the San Andreas fault. These features all record crustal-scale tilting to the northeast that likely started when the San Jacinto fault zone initiated ca. 1.2 Ma. Tilting appears to be driven by oblique shortening and loading across a northeast-dipping southern San Andreas fault, consistent with the results of a recent boundary-element modeling study.

SCIGN; new Southern California GPS network advances the study of earthquakes

USGS Publications Warehouse

Hudnut, Ken; King, Nancy

2001-01-01

Southern California is a giant jigsaw puzzle, and scientists are now using GPS satellites to track the pieces. These puzzle pieces are continuously moving, slowly straining the faults in between. That strain is then eventually released in earthquakes. The innovative Southern California Integrated GPS Network (SCIGN) tracks the motions of these pieces over most of southern California with unprecedented precision. This new network greatly improves the ability to assess seismic hazards and quickly measure the larger displacements that occur during and immediatelyafter earthquakes.

Relationship between annual precipitation variability and ENSO in Southern California for the Common Era (last 2,000 years)

NASA Astrophysics Data System (ADS)

DU, X.; Hendy, I. L.; Hinnov, L.; Brown, E. T.; Schimmelmann, A.; Pak, D. K.

2017-12-01

The El Niño-Southern Oscillation (ENSO) has a major influence on Southern California's hydroclimate as demonstrated by both historical observations and model simulations. Santa Barbara Basin (SBB) off Southern California preserves a unique varved (i.e. annually laminated) marine sedimentary archive of modern and Holocene hydroclimate variability, notably including the transition from the regionally dry Medieval Climate Anomaly (MCA) to the wetter Little Ice Age (LIA). Here we present sub-annually resolved scanning XRF elemental counts for the last 2,000 years in SBB from core SPR0901-03KC. Titanium (associated with silicate minerals) is delivered more efficiently to SBB sediments during times of enhanced river flow and in the Mediterranean climate of Southern California, river flow only occurs after precipitation. The Ti record suggests that the precipitation frequency was reduced during the MCA except for a pluvial episode at CE 1075-1121, but increased during the LIA. Time series analysis of Ti counts indicates ENSO variability robustly increased during the intervals CE 450-520, 650-720, 980-1150, 1380-1550 and 1720-1750, and experienced relatively quiescent intervals between CE 50-150, 250-400, 550-650, 750-950, 1150-1280 and 1580-1620. Generally the LIA in Southern California is characterized by more active ENSO variability with long periodicities (4-7 yr) and multi-decadal variability (54 yr). MCA drought episodes were associated with less active ENSO. Active ENSO variability in Southern California during the last 2,000 years coincided with reconstructed southward migration of the Intertropical Convergence Zone (ITCZ) suggesting the ITCZ may play a role in the waxing and waning of ENSO teleconnections between the central Pacific and the west coast of North America.

Five southern California oaks: identification and postfire management

Treesearch

Timothy R. Plumb; Anthony P. Gomez

1983-01-01

Oak trees in California are subject to periodic burning by fire, but their trunks and crowns vary in tolerance to fire. And once burned, oaks are difficult to identify by species. Fifteen oak species grow in California. This report provides keys to identifying five species of southern California oaks: coast live oak (Quercus agrifolia Née...

Factsheet for the California No-Discharge Zone Prohibiting Vessel Sewage in all California Marine Waters

EPA Pesticide Factsheets

The factsheet was produced by EPA Region 9 for California No Discharge Zone final rule. It includes background information, as well as a frequently asked questions (FAQs) section. The document also includes a map of California no discharge zones.

78 FR 22869 - Southern California Gas Company; Notice of Amendment

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-17

...] Southern California Gas Company; Notice of Amendment Take notice that on March 29, 2013, Southern California Gas Company (``SoCalGas'') filed two amendments to its November 21, 2012, petition for rate approval. SoCalGas states that the first amendment is to implement, pursuant to section 284.123, the rates...

Quantifying Vertical Exhumation in Intracontinental Strike-Slip Faults: the Garlock fault zone, southern California

NASA Astrophysics Data System (ADS)

Chinn, L.; Blythe, A. E.; Fendick, A.

2012-12-01

New apatite fission-track ages show varying rates of vertical exhumation at the eastern terminus of the Garlock fault zone. The Garlock fault zone is a 260 km long east-northeast striking strike-slip fault with as much as 64 km of sinistral offset. The Garlock fault zone terminates in the east in the Avawatz Mountains, at the intersection with the dextral Southern Death Valley fault zone. Although motion along the Garlock fault west of the Avawatz Mountains is considered purely strike-slip, uplift and exhumation of bedrock in the Avawatz Mountains south of the Garlock fault, as recently as 5 Ma, indicates that transpression plays an important role at this location and is perhaps related to a restricting bend as the fault wraps around and terminates southeastward along the Avawatz Mountains. In this study we complement extant thermochronometric ages from within the Avawatz core with new low temperature fission-track ages from samples collected within the adjacent Garlock and Southern Death Valley fault zones. These thermochronometric data indicate that vertical exhumation rates vary within the fault zone. Two Miocene ages (10.2 (+5.0/-3.4) Ma, 9.0 (+2.2/-1.8) Ma) indicate at least ~3.3 km of vertical exhumation at ~0.35 mm/yr, assuming a 30°C/km geothermal gradient, along a 2 km transect parallel and adjacent to the Mule Spring fault. An older Eocene age (42.9 (+8.7/-7.3) Ma) indicates ~3.3 km of vertical exhumation at ~0.08 mm/yr. These results are consistent with published exhumation rates of 0.35 mm/yr between ~7 and ~4 Ma and 0.13 mm/yr between ~15 and ~9 Ma, as determined by apatite fission-track and U-Th/He thermochronometry in the hanging-wall of the Mule Spring fault. Similar exhumation rates on both sides of the Mule Spring fault support three separate models: 1) Thrusting is no longer active along the Mule Spring fault, 2) Faulting is dominantly strike-slip at the sample locations, or 3) Miocene-present uplift and exhumation is below detection levels

Assessment of Southern California environment from ERTS-1

NASA Technical Reports Server (NTRS)

Bowden, L. W.; Viellenave, J. H.

1973-01-01

ERTS-1 imagery is a useful source of data for evaluation of earth resources in Southern California. The improving quality of ERTS-1 imagery, and our increasing ability to enhance the imagery has resulted in studies of a variety of phenomena in several Southern California environments. These investigations have produced several significant results of varying detail. They include the detection and identification of macro-scale tectonic and vegetational patterns, as well as detailed analysis of urban and agricultural processes. The sequential nature of ERTS-1 imagery has allowed these studies to monitor significant changes in the environment. In addiation, some preliminary work has begun directed toward assessing the impact of expanding recreation, agriculture and urbanization into the fragile desert environment. Refinement of enhancement and mapping techniques and more intensive analysis of ERTS-1 imagery should lead to a greater capability to extract detailed information for more precise evaluations and more accurate monitoring of earth resources in Southern California.

Sea otters are recolonizing southern California in fits and starts

USGS Publications Warehouse

Lafferty, Kevin D.; Tinker, M. Tim

2014-01-01

After near extinction as a result of the fur trade in the 1700s and 1800s, the southern sea otter slowly reoccupied the core of its range in central California. Range expansion beyond central California is seen as key to full recovery of otters, but the rate of expansion has been sporadic, raising concerns about habitat quality in southern California. To describe the range expansion of sea otters from central into southern California, we used skiff surveys, aerial surveys, and archival time-depth recorders from 2004 to 2013. These observations show that range expansion began when male otters swam southeast of Point Conception (Cojo Anchorage), perhaps to seek refuge from bad weather and to feed on unexploited resources. After several years of seasonal use by male groups, females began to use the area, leading to reproduction and a secondary increase in abundance. In contrast, a second male group that moved farther down the coast to Coal Oil Point stalled and retreated. Such range expansion and contraction can be explained by the social nature of sea otters, which acts to slow dispersal away from groups. Otter densities at Cojo Anchorage are now approaching equilibrium levels reported for central California. As in central California, otters rested in and near kelp forest habitat, but used deeper water for foraging. Together, these observations suggest habitat in the Santa Barbara Channel can still support sea otters, but range expansion of otters into southern California will be episodic due to social dynamics.

The impact of electric vehicles on the Southern California Edison System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, A.

1992-07-01

This report describes the results of the first phase of an investigation of the impacts of electric vehicles (EVs) in southern California. The investigation focuses on the Southern California Edison Company (SCE) which provides electric service for approximately 60% of southern California. The project is supported by the Air Quality Impacts of Energy Efficiency'' Program of the California Institute for Energy Efficiency (CIEE). The first phase of the research is organized around how EVs might be viewed by customers, vehicle manufacturers and electric utility companies. The vehicle manufacturers' view has been studied with special emphasis on the role of marketablemore » permit systems. The utilities' view of EVs is the subject of this report. The review is particularly important as several case studies of EVs in southern California have been conducted in recent years. The dynamics of a growing population of EVs is explained. Chapter 5 explains a simple method of deriving the electricity demands which could result from the operation of EVs in southern California. The method is demonstrated for several simple examples and then used to find the demands associated with each of the eight EV scenarios. Chapter 6 reports the impacts on SCE operations from the new demands for electricity. Impacts are summarized in terms of system operating costs, reliability of service, and changes in the utility's average electric rate. Chapter 7 turns to the emissions of air pollutants released by the operation of EVs, conventional vehicles (CVs) and power plants. Chapter 8 takes the air pollution analysis one step further by examining the possible reduction in ambient ozone concentration in southern California.« less

The 2007 southern California wildfires: Lessons in complexity

USGS Publications Warehouse

Keeley, J.E.; Safford, H.; Fotheringham, C.J.; Franklin, J.; Moritz, M.

2009-01-01

The 2007 wildfire season in southern California burned over 1,000,000 ac (400,000 ha) and included several megafires. We use the 2007 fires as a case study to draw three major lessons about wildfires and wildfire complexity in southern California. First, the great majority of large fires in southern California occur in the autumn under the influence of Santa Ana windstorms. These fires also cost the most to contain and cause the most damage to life and property, and the October 2007 fires were no exception because thousands of homes were lost and seven people were killed. Being pushed by wind gusts over 100 kph, young fuels presented little barrier to their spread as the 2007 fires reburned considerable portions of the area burned in the historic 2003 fire season. Adding to the size of these fires was the historic 2006-2007 drought that contributed to high dead fuel loads and long distance spotting. As in 2003, young chaparral stands and fuel treatments were not reliable barriers to fire in October 2007. Second, the Zaca Fire in July and August 2007 showed that other factors besides high winds can sometimes combine to create conditions for large fires in southern California. Spring and summer fires in southern California chaparral are usually easily contained because of higher fuel moisture and the general lack of high winds. However, the Zaca Fire burned in a remote wilderness area of rugged terrain that made access difficult. In addition, because of its remoteness, anthropogenic ignitions have been low and stand age and fuel loads were high. Coupled with this was severe drought that year that generated fuel moisture levels considerably below normal for early summer. A third lesson comes from 2007 conifer forest fires in the southern California mountains. In contrast to lower elevation chaparral, fire suppression has led to major increases in conifer forest fuels that can lead to unnaturally severe fires when ignitions escape control. The Slide and Grass Valley

THE GREAT SOUTHERN CALIFORNIA SHAKEOUT: Earthquake Science for 22 Million People

NASA Astrophysics Data System (ADS)

Jones, L.; Cox, D.; Perry, S.; Hudnut, K.; Benthien, M.; Bwarie, J.; Vinci, M.; Buchanan, M.; Long, K.; Sinha, S.; Collins, L.

2008-12-01

Earthquake science is being communicated to and used by the 22 million residents of southern California to improve resiliency to future earthquakes through the Great Southern California ShakeOut. The ShakeOut began when the USGS partnered with the California Geological Survey, Southern California Earthquake Center and many other organizations to bring 300 scientists and engineers together to formulate a comprehensive description of a plausible major earthquake, released in May 2008, as the ShakeOut Scenario, a description of the impacts and consequences of a M7.8 earthquake on the Southern San Andreas Fault (USGS OFR2008-1150). The Great Southern California ShakeOut was a week of special events featuring the largest earthquake drill in United States history. The ShakeOut drill occurred in houses, businesses, and public spaces throughout southern California at 10AM on November 13, 2008, when southern Californians were asked to pretend that the M7.8 scenario earthquake had occurred and to practice actions that could reduce the impact on their lives. Residents, organizations, schools and businesses registered to participate in the drill through www.shakeout.org where they could get accessible information about the scenario earthquake and share ideas for better reparation. As of September 8, 2008, over 2.7 million confirmed participants had been registered. The primary message of the ShakeOut is that what we do now, before a big earthquake, will determine what our lives will be like after. The goal of the ShakeOut has been to change the culture of earthquake preparedness in southern California, making earthquakes a reality that are regularly discussed. This implements the sociological finding that 'milling,' discussing a problem with loved ones, is a prerequisite to taking action. ShakeOut milling is taking place at all levels from individuals and families, to corporations and governments. Actions taken as a result of the ShakeOut include the adoption of earthquake

The southern California uplift and associated earthquakes

USGS Publications Warehouse

Castle, R.O.; Bernknopf, R.L.

1996-01-01

Southern California earthquakes ??? M5.5 during the period 1955/01/01-1994/01/17 were concentrated along or adjacent to the south flank of the southern California uplift, as defined both at its culmination and following its partial collapse. Spatial clustering of these earthquakes within three more-or-less distinct groups suggests either gaps along the south flank that were previously filled or are yet to be filled. Nearly all of the indicated earthquakes accompanied or followed partial collapse of the uplift, and seismic activity within this regime seems to have been increasing through at least 1994/01/17. Copyright 1996 by the American Geophysical Union.

The response of southern California ecosystems to Younger Dryas-like rapid climate change: Comparison of glacial terminations 1 and 5.

NASA Astrophysics Data System (ADS)

Heusser, L. E.; Hendy, I. L.

2015-12-01

The Younger Dryas is a well-known rapid climatic cooling that interrupted the Marine Isotope Stage (MIS) 1-2 deglacial warming of Termination 1. This cool event has been associated with ice sheet readvance, meridional overturning, circulation changes, and southward movement of the Intertropical Convergence Zone. In Southern California, the Younger Dryas has been associated with cooler SST, low marine productivity, a well-ventilated oxygen minimum zone, and a wetter climate. Similar rapid cooling events have been found at other terminations including Termination 5 at the MIS 11-12 deglaciation (~425 Ka) identified by ice rafting events in the North Atlantic. Here we present new pollen census data from a unique suite of cores taken from the sub-oxic sediments of Santa Barbara Basin (MV0508-15JC, MV0805-20JC, MV0508-33JC, 29JC and 21JC). These short cores, collected on a truncated anticline within SBB, provide the opportunity to examine the response of southern California terrestrial and marine ecosystems to rapid climate change during the MIS 11-12 deglaciation (Termination 5), which is identified by a bioturbated interval within a sequence of laminated sediments. During Termination 1, changes in Southern California precipitation are reflected in pollen- based reconstructions Southern California vegetation. The high precipitation of glacial montane-coniferous assemblages of pine (Pinus) and Juniper (Juniperus/Calocedrus) transitions into interglacial drought, as expresssed by arid oak (Quercus)/chaparral vegetation. The Younger Dryas interrupts the transition as a high-amplitude pulse in pine associated with increased Gramineae (grass). Termination 5 differs, as the high precipitation of glacial montane-coniferous assemblages do not transition into arid oak/chaparral vegetation. However, a Younger Dryas-like rapid climate event was associated with increased pine and grass.

Interseismic secular deformation in Southern California from InSAR-derived maps over the time period between 1992 and 2006

NASA Astrophysics Data System (ADS)

Rivet, D. N.; Fialko, Y.

2007-12-01

We analyzed secular deformation in Southern California using an extensive catalog of InSAR data that spans 15 years between 1992 and 2006. We generated a map of the satellite line-of-sight displacements based on a stack of ~300 interferograms from 6 adjacent tracks of the ERS-1 and ERS-2 satellites covering Southern California. The main limitation to the accuracy of InSAR measurements of tectonic deformation is the atmospheric phase delay. We introduce a new method aimed to improve the signal-to-noise ratio in the InSAR- derived maps of secular deformation. The method involves identifying SAR acquisitions that are highly affected by atmospheric noise, and an optimal choice of interferometric pairs for stacking. We begin by generating a set of all possible interferometric pairs having baselines and time spans within prescribed limits. We then select interferograms with sufficiently high correlation. Subsequently, we identify noisy SAR acquisitions by means of calculating RMS of the phase signal. Finally, we generate a stack of interferograms by following a "connectivity tree" that minimizes contributions of noisy scenes. Using this method we obtained a continuous velocity field characterizing surface deformation in Southern California over the last 15 years. We identify interseismic deformation on a number of major faults, including those of the southern San Andreas system, and the Eastern California Shear Zone (ECSZ). We study the time dependency from 1992 to 2006 of those deformation patterns. Variations in the line-of- sight velocity across the Eastern California Shear Zone are non-monotonic, with the maximum along the strike of the Hector Mine fault of ~4 mm/yr, and total LOS velocity between the eastern and western boundaries of the shear zone of less than 2 mm/yr. We observe increases in the radar range to the east of ECSZ. This signal most likely results from subsidence east of the Death Valley-Mule Springs fault system, either due to hydrologic effects, or

75 FR 63166 - Southern California Gas Company; Notice of Baseline Filing

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-135-001] Southern California Gas Company; Notice of Baseline Filing October 6, 2010. Take notice that on October 4, 2010, Southern California Gas Company submitted a revised baseline filing of its Statement of Operating...

Naphthalene distributions and human exposure in Southern California

NASA Astrophysics Data System (ADS)

Lu, Rong; Wu, Jun; Turco, Richard P.; Winer, Arthur M.; Atkinson, Roger; Arey, Janet; Paulson, Suzanne E.; Lurmann, Fred W.; Miguel, Antonio H.; Eiguren-Fernandez, Arantzazu

The regional distribution of, and human exposure to, naphthalene are investigated for Southern California. A comprehensive approach is taken in which advanced models are linked for the first time to quantify population exposure to the emissions of naphthalene throughout Southern California. Naphthalene is the simplest and most abundant of the polycyclic aromatic hydrocarbons found in polluted urban environments, and has been detected in both outdoor and indoor air samples. Exposure to high concentrations of naphthalene may have adverse health effects, possibly causing cancer in humans. Among the significant emission sources are volatilization from naphthalene-containing products, petroleum refining, and combustion of fossil fuels and wood. Gasoline and diesel engine exhaust, with related vaporization from fuels, are found to contribute roughly half of the daily total naphthalene burden in Southern California. As part of this study, the emission inventory for naphthalene has been verified against new field measurements of the naphthalene-to-benzene ratio in a busy traffic tunnel in Los Angeles, supporting the modeling work carried out here. The Surface Meteorology and Ozone Generation (SMOG) airshed model is used to compute the spatial and temporal distributions of naphthalene and its photooxidation products in Southern California. The present simulations reveal a high degree of spatial variability in the concentrations of naphthalene-related species, with large diurnal and seasonal variations as well. Peak naphthalene concentrations are estimated to occur in the early morning hours in the winter season. The naphthalene concentration estimates obtained from the SMOG model are employed in the Regional Human Exposure (REHEX) model to calculate population exposure statistics. Results show average hourly naphthalene exposures in Southern California under summer and winter conditions of 270 and 430 ng m -3, respectively. Exposure to significantly higher concentrations

Paleoseismology of the Southern Section of the Black Mountains and Southern Death Valley Fault Zones, Death Valley, United States

USGS Publications Warehouse

Sohn, Marsha S.; Knott, Jeffrey R.; Mahan, Shannon

2014-01-01

The Death Valley Fault System (DVFS) is part of the southern Walker Lane–eastern California shear zone. The normal Black Mountains Fault Zone (BMFZ) and the right-lateral Southern Death Valley Fault Zone (SDVFZ) are two components of the DVFS. Estimates of late Pleistocene-Holocene slip rates and recurrence intervals for these two fault zones are uncertain owing to poor relative age control. The BMFZ southernmost section (Section 1W) steps basinward and preserves multiple scarps in the Quaternary alluvial fans. We present optically stimulated luminescence (OSL) dates ranging from 27 to 4 ka of fluvial and eolian sand lenses interbedded with alluvial-fan deposits offset by the BMFZ. By cross-cutting relations, we infer that there were three separate ground-rupturing earthquakes on BMFZ Section 1W with vertical displacement between 5.5 m and 2.75 m. The slip-rate estimate is ∼0.2 to 1.8 mm/yr, with an earthquake recurrence interval of 4,500 to 2,000 years. Slip-per-event measurements indicate Mw 7.0 to 7.2 earthquakes. The 27–4-ka OSL-dated alluvial fans also overlie the putative Cinder Hill tephra layer. Cinder Hill is offset ∼213 m by SDVFZ, which yields a tentative slip rate of 1 to 8 mm/yr for the SDVFZ.

Geomorphology and Tectonics at the Intersection of Silurian and Death Valleys, Southern California - 2005 Guidebook Pacific Cell Friends of the Pleistocene

USGS Publications Warehouse

Miller, David M.; Valin, Zenon C.

2007-01-01

This publication describes results from new regional and detailed surficial geologic mapping, combined with geomorphologic, geochronologic, and tectonic studies, in Silurian Valley and Death Valley, California. The studies address a long-standing problem, the tectonic and geomorphic evolution of the intersection between three regional tectonic provinces: the eastern California shear zone, the Basin and Range region of southern Nevada and adjacent California, and the eastern Mojave Desert region. The chapters represent work presented on the 2005 Friends of the Pleistocene field trip and meeting as well as the field trip road log.

Automatic 3D Moment tensor inversions for southern California earthquakes

NASA Astrophysics Data System (ADS)

Liu, Q.; Tape, C.; Friberg, P.; Tromp, J.

2008-12-01

We present a new source mechanism (moment-tensor and depth) catalog for about 150 recent southern California earthquakes with Mw ≥ 3.5. We carefully select the initial solutions from a few available earthquake catalogs as well as our own preliminary 3D moment tensor inversion results. We pick useful data windows by assessing the quality of fits between the data and synthetics using an automatic windowing package FLEXWIN (Maggi et al 2008). We compute the source Fréchet derivatives of moment-tensor elements and depth for a recent 3D southern California velocity model inverted based upon finite-frequency event kernels calculated by the adjoint methods and a nonlinear conjugate gradient technique with subspace preconditioning (Tape et al 2008). We then invert for the source mechanisms and event depths based upon the techniques introduced by Liu et al 2005. We assess the quality of this new catalog, as well as the other existing ones, by computing the 3D synthetics for the updated 3D southern California model. We also plan to implement the moment-tensor inversion methods to automatically determine the source mechanisms for earthquakes with Mw ≥ 3.5 in southern California.

Preparing for a "Big One": The great southern California shakeout

USGS Publications Warehouse

Jones, L.M.; Benthien, M.

2011-01-01

The Great Southern California ShakeOut was a week of special events featuring the largest earthquake drill in United States history. On November 13, 2008, over 5 million Southern Californians pretended that the magnitude-7.8 ShakeOut scenario earthquake was occurring and practiced actions derived from results of the ShakeOut Scenario, to reduce the impact of a real, San Andreas Fault event. The communications campaign was based on four principles: 1) consistent messaging from multiple sources; 2) visual reinforcement: 3) encouragement of "milling"; and 4) focus on concrete actions. The goals of the Shake-Out established in Spring 2008 were: 1) to register 5 million people to participate in the drill; 2) to change the culture of earthquake preparedness in Southern California; and 3) to reduce earthquake losses in Southern California. Over 90% of the registrants surveyed the next year reported improvement in earthquake preparedness at their organization as a result of the ShakeOut. ?? 2011, Earthquake Engineering Research Institute.

Technology penetration of endovascular aortic aneurysm repair in southern California.

PubMed

Shah, Haimesh; Kumar, S Ram; Major, Kevin; Hood, Douglas; Rowe, Vincent; Weaver, Fred A

2006-11-01

Our objective was to investigate the penetration of endovascular abdominal aortic aneurysm repair (EVAR) in the large, diverse health-care market of southern California over 3 years and to study variability in the pattern of distribution of EVAR in southern California counties by analyzing available demographic, geographic, and socioeconomic data from California state health-care databases. Information abstracted from the inpatient hospital discharge data for patients undergoing AAA repair for the years 2001, 2002, and 2003, derived from the Office of Statewide Health Planning and Development, included age, gender, race, hospitals performing EVAR, and payors for the service. Per-capita income (PCI) for the year 1999 and the population size of each county for the respective years were obtained from the U.S. Census Bureau. Data pertaining to members of the Southern California Vascular Surgical Society (SCVSS) serving the southern California region were obtained from the SCVSS membership directory. Data were categorized based on 10 counties in southern California. All the above variables were analyzed using the chi-squared test, with p < 0.05 considered significant. The proportions of EVAR for the years 2001, 2002, and 2003 were 15.4% (n = 409), 20.2% (n = 492), and 25.9% (n = 566), respectively. This is a 67.8% (p < 0.0001) increase in EVAR application in southern California since 2001. However, the proportion of EVAR varied among counties (p < 0.0001), with 457 EVARs performed in Los Angeles County and eight in Imperial County during the study period. EVAR proportion was higher in patients aged > or =65 years (p < 0.0001) and male patients (p < 0.0001). The proportion of EVAR was significantly higher in counties with more than 20 vascular surgeons available (p < 0.0001) and PCI >21,000 US$ (p < 0.0001) and in Medicare, health maintenance organization, preferred provider organization, and private insurance holders (p < 0.0001). There was a trend toward increased

Smoke from Station Fire Blankets Southern California

NASA Image and Video Library

2009-09-01

The Multi-angle Imaging SpectroRadiometer MISR instrument on NASA Terra satellite captured this Aug. 30 image of smoke plumes from the Station and other wildfires burning throughout Southern California.

How does the 2010 El Mayor - Cucapah Earthquake Rupture Connect to the Southern California Plate Boundary Fault System

NASA Astrophysics Data System (ADS)

Donnellan, A.; Ben-Zion, Y.; Arrowsmith, R.

2016-12-01

The Pacific - North American plate boundary in southern California is marked by several major strike slip faults. The 2010 M7.2 El Mayor - Cucapah earthquake ruptured 120 km of upper crust in Baja California to the US-Mexico border. The earthquake triggered slip along an extensive network of faults in the Salton Trough from the Mexican border to the southern end of the San Andreas fault. Earthquakes >M5 were triggered in the gap between the Laguna Salada and Elsinore faults at Ocotillo and on the Coyote Creek segment of the San Jacinto fault 20 km northwest of Borrego Springs. UAVSAR observations, collected since October of 2009, measure slip associated with the M5.7 Ocotillo aftershock with deformation continuing into 2014. The Elsinore fault has been remarkably quiet, however, with only M5.0 and M5.2 earthquakes occurring on the Coyote Mountains segment of the fault in 1940 and 1968 respectively. In contrast, the Imperial Valley has been quite active historically with numerous moderate events occurring since 1935. Moderate event activity is increasing along the San Jacinto fault zone (SJFZ), especially the trifurcation area, where 6 of 12 historic earthquakes in this 20 km long fault zone have occurred since 2000. However, no recent deformation has been detected using UAVSAR measurements in this area, including the recent M5.2 June 2016 Borrego earthquake. Does the El Mayor - Cucapah rupture connect to and transfer stress primarily to a single southern California fault or several? What is its role relative to the background plate motion? UAVSAR observations indicate that the southward extension of the Elsinore fault has recently experienced the most localized deformation. Seismicity suggests that the San Jacinto fault is more active than neighboring major faults, and geologic evidence suggests that the Southern San Andreas fault has been the major plate boundary fault in southern California. Topographic data with 3-4 cm resolution using structure from motion from

Researching Indigenous Indians in Southern California: Commentary, Bibliography, and Online Resources

ERIC Educational Resources Information Center

Sutton, Imre

2006-01-01

This article seeks to present a continuing bibliography of research on Southern California Indians from the past 20 years, and sometimes beyond. The coverage reaches outside the variably defined bounds of Southern California so that it includes peripheral groups such as the Timbisha Shoshone of Death Valley and one or more groups in the Owens…

78 FR 49749 - Southern California Edison, City of Banning, California; Notice of Meeting To Conduct a Technical...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-15

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 344-023-California; Project No. 14520-000-California] Southern California Edison, City of Banning, California; Notice of Meeting To Conduct a Technical Conference for the San Gorgonio Hydroelectric Project and the Proposed Whitewater Flume Water Power Project a. Date and Time...

Fertilization and irrigation of Eucalyptus in southern California

Treesearch

Paul W. Moore

1983-01-01

An experiment to determine the interaction of three levels of irrigation, three levels of fertility and three densities of planting was started at the University of California Moreno Ranch in 1982. Differential irrigation and fertility treatments will begin in June of 1983. Some current practices of irrigation and fertilization by southern California growers are...

High-resolution boomer seismic-reflection profiles of the shelf off southern California from cruise A-1-00-SC: Santa Monica Bay to San Diego

USGS Publications Warehouse

Gutmacher, Christina E.; Ross, Stephanie L.; Triezenberg, Peter J.; Sliter, Ray W.; Normark, William R.; Edwards, Brian D.

2006-01-01

High-resolution boomer data were collected in the California Continental Borderland as part of the southern California Earthquake Hazards Task of the Southern California Coastal and Marine Geology Regional Investigations Project. During the period from 1997 to 2002, five data-acquisition cruises collected seismic-reflection data using several different systems from offshore Santa Barbara, California, south to the Exclusive Economic Zone boundary with Mexico. A key mission of this project was to map late Quaternary deformation in addition to improving our understanding of which offshore fault zones might have potential to damage highly populated areas of southern California. State regulations concerning the use of seismic-reflection equipment within three miles of the coastline precluded the routine gathering of high-resolution multichannel data in that swath adjacent to the coast. Boomer seismic-reflection data, however, can be obtained within the state 3-mile limit provided the operation receives authorization from the California State Lands Commission. The Geopulse boomer data accessible through this report were collected on the cruise A-1-00-SC, which was the only survey where we requested permission to work inside the 3-mile limit of the State of California. These data are critical to discovering connections between onshore and offshore faults, the overall lengths of which are related to the potential size of an earthquake that might be generated along them. The 2000 survey was designed to fill the gap between onshore data and reflection data obtained in deeper water on previous cruises as well as data anticipated from future surveys. This report includes trackline maps showing the location of the data, as well as both digital data files (SEG-Y) and images of all of the profiles.

Slip rate on the San Diego trough fault zone, inner California Borderland, and the 1986 Oceanside earthquake swarm revisited

USGS Publications Warehouse

Ryan, Holly F.; Conrad, James E.; Paull, C.K.; McGann, Mary

2012-01-01

The San Diego trough fault zone (SDTFZ) is part of a 90-km-wide zone of faults within the inner California Borderland that accommodates motion between the Pacific and North American plates. Along with most faults offshore southern California, the slip rate and paleoseismic history of the SDTFZ are unknown. We present new seismic reflection data that show that the fault zone steps across a 5-km-wide stepover to continue for an additional 60 km north of its previously mapped extent. The 1986 Oceanside earthquake swarm is located within the 20-km-long restraining stepover. Farther north, at the latitude of Santa Catalina Island, the SDTFZ bends 20° to the west and may be linked via a complex zone of folds with the San Pedro basin fault zone (SPBFZ). In a cooperative program between the U.S. Geological Survey (USGS) and the Monterey Bay Aquarium Research Institute (MBARI), we measure and date the coseismic offset of a submarine channel that intersects the fault zone near the SDTFZ–SPBFZ junction. We estimate a horizontal slip rate of about 1:5 0:3 mm=yr over the past 12,270 yr.

Fin whale song variability in southern California and the Gulf of California.

PubMed

Širović, Ana; Oleson, Erin M; Buccowich, Jasmine; Rice, Ally; Bayless, Alexandra R

2017-08-31

Songs are distinct, patterned sounds produced by a variety of animals including baleen whales. Fin whale songs, which consist of short pulses repeated at regular interpulse intervals (IPIs), have been suggested as a tool to distinguish populations. Fin whale songs were analyzed from data collected from 2000-2012 in Southern California and from 2004-2010 in the Gulf of California using autonomous acoustic recorders. IPIs were measured for each identifiable song sequence during two random days of each month with recordings. Four distinct song types were identified: long doublet, short doublet, long triplet, and short triplet. Long and short doublets were the dominant songs in Southern California, while long and short triplets were dominant in the Gulf of California. An abrupt change in song type occurred in both areas during the monitoring period. We argue that each song type is unique to a population and these changes represent a shift in the primary population in the monitoring area. Occasional temporal and spatial song overlap indicated some exchange or visitation among populations. Fin whales appear to synchronize and gradually modify song rhythm over long time scales. A better understanding of the evolutionary and ecological importance of songs to fin whale populations is needed.

46 CFR 42.30-10 - Southern Winter Seasonal Zone.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Island; thence the rhumb line to Black Rock Point on Stewart Island; thence the rhumb line to the point... BY SEA Zones, Areas, and Seasonal Periods § 42.30-10 Southern Winter Seasonal Zone. (a) The northern boundary of the Southern Winter Seasonal Zone is the rhumb line from the east coast of the American...

50 CFR 226.210 - Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California Coasts Coho Salmon (Oncorhynchus kisutch). 226.210 Section 226.210 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC...

Regeneration of native California oaks in the forest zone [Abstract

Treesearch

P.M. McDonald

1999-01-01

The two native California oaks in the forest zone of California are California black oak (Quercus kelloggii Newb.) and tanoak (Lithocarpus densiflorus [Hook. and Arn.] Rehd.). Both are ancient species with many adaptations to withstand California's Mediterranean climate, but some weaknesses as well. Both sprout vigorously...

Salary survey of the Medical Library Group of Southern California and Arizona.

PubMed Central

Smith, J L; Connolly, B F; Davis, M; Graham, E; Wheeler, S

1984-01-01

The 1982 salary survey of the Medical Library Group of Southern California and Arizona (MLGSCA) indicates that 211 health sciences librarians in Southern California and Arizona earned a mean annual salary of $20,910 for 1982. Data analysis shows a positive correlation between salary and educational level. Other factors found to affect salary were job history, number of positions held, MLA certification, and professional responsibility. Age, gender, and MLA certification did not have a consistent positive correlation with salary. Results indicate that the salaries of hospital librarians are, on the average, roughly comparable to those of academic librarians in Southern California and Arizona. PMID:6743878

AmeriFlux US-SCg Southern California Climate Gradient - Grassland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Mike

This is the AmeriFlux version of the carbon flux data for the site US-SCg Southern California Climate Gradient - Grassland. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of six Southern California Climate Gradient flux towers operated along an elevation gradient (sites are US-SCg, US-SCs, US-SCf, US-SCw, US-SCc, US-SCd). This site is a grassland that was historically dominated by exotic annuals and that underwent restoration with a focus on native bunch grasses in the 2010s. The site has historically burned every 10-20 years, with a wildfire in October 2007. The restoration involved several yearsmore » of mowing and herbicide application to suppress exotics followed by dense planting of Nasella bunch grasses.« less

Structure of the San Andreas Fault Zone in the Salton Trough Region of Southern California: A Comparison with San Andreas Fault Structure in the Loma Prieta Area of Central California

NASA Astrophysics Data System (ADS)

Fuis, G. S.; Catchings, R.; Scheirer, D. S.; Goldman, M.; Zhang, E.; Bauer, K.

2016-12-01

The San Andreas fault (SAF) in the northern Salton Trough, or Coachella Valley, in southern California, appears non-vertical and non-planar. In cross section, it consists of a steeply dipping segment (75 deg dip NE) from the surface to 6- to 9-km depth, and a moderately dipping segment below 6- to 9-km depth (50-55 deg dip NE). It also appears to branch upward into a flower-like structure beginning below about 10-km depth. Images of the SAF zone in the Coachella Valley have been obtained from analysis of steep reflections, earthquakes, modeling of potential-field data, and P-wave tomography. Review of seismological and geodetic research on the 1989 M 6.9 Loma Prieta earthquake, in central California (e.g., U.S. Geological Survey Professional Paper 1550), shows several features of SAF zone structure similar to those seen in the northern Salton Trough. Aftershocks in the Loma Prieta epicentral area form two chief clusters, a tabular zone extending from 18- to 9-km depth and a complex cluster above 5-km depth. The deeper cluster has been interpreted to surround the chief rupture plane, which dips 65-70 deg SW. When double-difference earthquake locations are plotted, the shallower cluster contains tabular subclusters that appear to connect the main rupture with the surface traces of the Sargent and Berrocal faults. In addition, a diffuse cluster may surround a steep to vertical fault connecting the main rupture to the surface trace of the SAF. These interpreted fault connections from the main rupture to surface fault traces appear to define a flower-like structure, not unlike that seen above the moderately dipping segment of the SAF in the Coachella Valley. But importantly, the SAF, interpreted here to include the main rupture plane, appears segmented, as in the Coachella Valley, with a moderately dipping segment below 9-km depth and a steep to vertical segment above that depth. We hope to clarify fault-zone structure in the Loma Prieta area by reanalyzing active

The impact of electric vehicles on the Southern California Edison System. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, A.

1992-07-01

This report describes the results of the first phase of an investigation of the impacts of electric vehicles (EVs) in southern California. The investigation focuses on the Southern California Edison Company (SCE) which provides electric service for approximately 60% of southern California. The project is supported by the ``Air Quality Impacts of Energy Efficiency`` Program of the California Institute for Energy Efficiency (CIEE). The first phase of the research is organized around how EVs might be viewed by customers, vehicle manufacturers and electric utility companies. The vehicle manufacturers` view has been studied with special emphasis on the role of marketablemore » permit systems. The utilities` view of EVs is the subject of this report. The review is particularly important as several case studies of EVs in southern California have been conducted in recent years. The dynamics of a growing population of EVs is explained. Chapter 5 explains a simple method of deriving the electricity demands which could result from the operation of EVs in southern California. The method is demonstrated for several simple examples and then used to find the demands associated with each of the eight EV scenarios. Chapter 6 reports the impacts on SCE operations from the new demands for electricity. Impacts are summarized in terms of system operating costs, reliability of service, and changes in the utility`s average electric rate. Chapter 7 turns to the emissions of air pollutants released by the operation of EVs, conventional vehicles (CVs) and power plants. Chapter 8 takes the air pollution analysis one step further by examining the possible reduction in ambient ozone concentration in southern California.« less

AmeriFlux US-SCs Southern California Climate Gradient - Coastal Sage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Mike

This is the AmeriFlux version of the carbon flux data for the site US-SCs Southern California Climate Gradient - Coastal Sage. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of six Southern California Climate Gradient flux towers operated along an elevation gradient (sites are US-SCg, US-SCs, US-SCf, US-SCw, US-SCc, US-SCd). This site is a coastal sage shrubland. Coastal sage is a small stature, closed canopy vegetation dominated by drought deciduous shrubs. The site has historically burned every 10-20 years, with the wild fire in October 2007. The tower data sets includes this recovery process.

Enrichment of trace elements in garnet amphibolites from a paleo-subduction zone: Catalina Schist, southern California

USGS Publications Warehouse

Sorensen, Sorena S.; Grossman, J.N.

1989-01-01

The abundance, P-T stability, solubility, and element-partitioning behavior of minerals such as rutile, garnet, sphene, apatite, zircon, zoisite, and allanite are critical variables in models for mass transfer from the slab to the mantle wedge in deep regions of subduction zones. The influence of these minerals on the composition of subduction-related magmas has been inferred (and disputed) from inverse modelling of the geochemistry of island-arc basalt, or by experiment. Although direct samples of the dehydration + partial-melting region of a mature subduction zone have not been reported from subduction complexes, garnet amphibolites from melanges of circumpacific and Caribbean blueschist terranes reflect high T (>600??C) conditions in shallower regions. Such rocks record geochemical processes that affected deep-seated, high-T portions of paleo-subduction zones. In the Catalina Schist, a subduction-zone metamorphic terrane of southern California, metasomatized and migmatitic garnet amphibolites occur as blocks in a matrix of meta-ultramafic rocks. This mafic and ultramafic complex may represent either slab-derived material accreted to the mantle wedge of a nascent subduction zone or a portion of a shear zone closely related to the slab-mantle wedge contact, or both. The trace-element geochemistry of the complex and the distribution of trace elements among the minerals of garnet amphibolites were studied by INAA, XRF, electron microprobe, and SEM. In order of increasing alteration from a probable metabasalt protolith, three common types of garnet amphibolite blocks in the Catalina Schist are: (1) non-migmatitic, clinopyroxene-bearing blocks, which are compositionally similar to MORB that has lost an albite component; (2) garnet-amphibolite blocks, which have rinds that reflect local interaction between metabasite, metaperidotite, and fluid; and (3) migmatites that are extremely enriched in Th, HFSE, LREE, and other trace elements. These trace-element enrichments

Groundwater quality in the Southern Sacramento Valley, California

USGS Publications Warehouse

Bennett, George L.; Fram, Miranda S.; Belitz, Kenneth

2011-01-01

Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Southern Sacramento Valley is one of the study units being evaluated.

AmeriFlux US-SCf Southern California Climate Gradient - Oak/Pine Forest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Mike

This is the AmeriFlux version of the carbon flux data for the site US-SCf Southern California Climate Gradient - Oak/Pine Forest. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of six Southern California Climate Gradient flux towers operated along an elevation gradient (sites are US-SCg, US-SCs, US-SCf, US-SCw, US-SCc, US-SCd). This site is a mixed oak/pine forest. The site experiences episodic severe drought and mortality, and has also experienced occasional logging and wildfire. Drought and mortality was especially severe in the early 2000s.

Southern California Socioeconomic Assessment: Sociodemographic Conditions, Projections, and Quality of Life Indices

Treesearch

Rachel Struglia; Patricia l. Winter; Andrea Meyer

2003-01-01

This report summarizes findings from the regional and county socioeconomic assessment conducted for southern California. The 26-county region extends from San Diego to the San Francisco Bay Area. A majority of the state’s population resides within this region, which surrounds the four southern California National Forests (Angeles, Cleveland, Los Padres, and San...

NASA ER-2 Flies over Southern California Wildfires

NASA Image and Video Library

2017-12-11

NASA pilot Tim Williams flies the ER-2 high altitude airborne science platform carrying Jet Propulsion Laboratory’s AVIRIS spectral instrument over the Southern California wildfires on December 7, 2017.

A compilation of K-Ar-ages for southern California

USGS Publications Warehouse

Miller, Fred K.; Morton, Douglas M.; Morton, Janet L.; Miller, David M.

2014-01-01

The purpose of this report is to make available a large body of conventional K-Ar ages for granitic, volcanic, and metamorphic rocks collected in southern California. Although one interpretive map is included, the report consists primarily of a systematic listing, without discussion or interpretation, of published and unpublished ages that may be of value in future regional and other geologic studies. From 1973 to 1979, 468 rock samples from southern California were collected for conventional K-Ar dating under a regional geologic mapping project of Southern California (predecessor of the Southern California Areal Mapping Project). Most samples were collected and dated between 1974 and 1977. For 61 samples (13 percent of those collected), either they were discarded for varying reasons, or the original collection data were lost. For the remaining samples, 518 conventional K-Ar ages are reported here; coexisting mineral pairs were dated from many samples. Of these K-Ar ages, 225 are previously unpublished, and identified as such in table 1. All K-Ar ages are by conventional K-Ar analysis; no 40Ar/39Ar dating was done. Subsequent to the rock samples collected in the 1970s and reported here, 33 samples were collected and 38 conventional K-Ar ages determined under projects directed at (1) characterization of the Mesozoic and Cenozoic igneous rocks in and on both sides of the Transverse Ranges and (2) clarifying the Mesozoic and Cenozoic tectonics of the eastern Mojave Desert. Although previously published (Beckerman et al., 1982), another eight samples and 11 conventional K-Ar ages are included here, because they augment those completed under the previous two projects.

Probability of one or more M ≥7 earthquakes in southern California in 30 years

USGS Publications Warehouse

Savage, J.C.

1994-01-01

Eight earthquakes of magnitude greater than or equal to seven have occurred in southern California in the past 200 years. If one assumes that such events are the product of a Poisson process, the probability of one or more earthquakes of magnitude seven or larger in southern California within any 30 year interval is 67% ?? 23% (95% confidence interval). Because five of the eight M ??? 7 earthquakes in southern California in the last 200 years occurred away from the San Andreas fault system, the probability of one or more M ??? 7 earthquakes in southern California but not on the San Andreas fault system occurring within 30 years is 52% ?? 27% (95% confidence interval). -Author

A Seamless, High-Resolution, Coastal Digital Elevation Model (DEM) for Southern California

USGS Publications Warehouse

Barnard, Patrick L.; Hoover, Daniel

2010-01-01

A seamless, 3-meter digital elevation model (DEM) was constructed for the entire Southern California coastal zone, extending 473 km from Point Conception to the Mexican border. The goal was to integrate the most recent, high-resolution datasets available (for example, Light Detection and Ranging (Lidar) topography, multibeam and single beam sonar bathymetry, and Interferometric Synthetic Aperture Radar (IfSAR) topography) into a continuous surface from at least the 20-m isobath to the 20-m elevation contour. This dataset was produced to provide critical boundary conditions (bathymetry and topography) for a modeling effort designed to predict the impacts of severe winter storms on the Southern California coast (Barnard and others, 2009). The hazards model, run in real-time or with prescribed scenarios, incorporates atmospheric information (wind and pressure fields) with a suite of state-of-the-art physical process models (tide, surge, and wave) to enable detailed prediction of water levels, run-up, wave heights, and currents. Research-grade predictions of coastal flooding, inundation, erosion, and cliff failure are also included. The DEM was constructed to define the general shape of nearshore, beach and cliff surfaces as accurately as possible, with less emphasis on the detailed variations in elevation inland of the coast and on bathymetry inside harbors. As a result this DEM should not be used for navigation purposes.

Microwave radiometric studies and ground truth measurements of the NASA/USGS Southern California test site

NASA Technical Reports Server (NTRS)

Edgerton, A. T.; Trexler, D. T.; Sakamoto, S.; Jenkins, J. E.

1969-01-01

The field measurement program conducted at the NASA/USGS Southern California Test Site is discussed. Ground truth data and multifrequency microwave brightness data were acquired by a mobile field laboratory operating in conjunction with airborne instruments. The ground based investigations were performed at a number of locales representing a variety of terrains including open desert, cultivated fields, barren fields, portions of the San Andreas Fault Zone, and the Salton Sea. The measurements acquired ground truth data and microwave brightness data at wavelengths of 0.8 cm, 2.2 cm, and 21 cm.

Crustal Spreading in Southern California: The Imperial Valley and the Gulf of California formed by the rifting apart of a continental plate.

PubMed

Elders, W A; Rex, R W; Robinson, P T; Biehler, S; Meidav, T

1972-10-06

The current excitement among geologists and geophysicists stemming from the "new global tectonics" has led to a widespread, speculative reinterpretation of continental geology. The Gulf of California and its continuation into the Imperial Valley provide an excellent opportunity for studying the border zone between the North American and Pacific plates, and an interface of continental and oceanic tectonics. The Salton trough, the landward extension of the gulf, is a broad structural depression, comparable in size with the deeper marine basins of the southern part of the gulf, but here partially filled with sediments deposited by the Colorado River.

Earthquakes and faults in southern California (1970-2010)

USGS Publications Warehouse

Sleeter, Benjamin M.; Calzia, James P.; Walter, Stephen R.

2012-01-01

The map depicts both active and inactive faults and earthquakes magnitude 1.5 to 7.3 in southern California (1970–2010). The bathymetry was generated from digital files from the California Department of Fish And Game, Marine Region, Coastal Bathymetry Project. Elevation data are from the U.S. Geological Survey National Elevation Database. Landsat satellite image is from fourteen Landsat 5 Thematic Mapper scenes collected between 2009 and 2010. Fault data are reproduced with permission from 2006 California Geological Survey and U.S. Geological Survey data. The earthquake data are from the U.S. Geological Survey National Earthquake Information Center.

Discussing epigenetics in Southern California

PubMed Central

2012-01-01

With the goal of discussing how epigenetic control and chromatin remodeling contribute to the various processes that lead to cellular plasticity and disease, this symposium marks the collaboration between the Institut National de la Santé et de la Recherche Médicale (INSERM) in France and the University of California, Irvine (UCI). Organized by Paolo Sassone-Corsi (UCI) and held at the Beckman Center of the National Academy of Sciences at the UCI campus December 15–16, 2011, this was the first of a series of international conferences on epigenetics dedicated to the scientific community in Southern California. The meeting also served as the official kick off for the newly formed Center for Epigenetics and Metabolism at the School of Medicine, UCI (http://cem.igb.uci.edu). PMID:22414797

Viscoelastic coupling model of the San Andreas fault along the big bend, southern California

USGS Publications Warehouse

Savage, J.C.; Lisowski, M.

1997-01-01

The big bend segment of the San Andreas fault is the 300-km-long segment in southern California that strikes about N65??W, roughly 25?? counterclockwise from the local tangent to the small circle about the Pacific-North America pole of rotation. The broad distribution of deformation of trilateration networks along this segment implies a locking depth of at least 25 km as interpreted by the conventional model of strain accumulation (continuous slip on the fault below the locking depth at the rate of relative plate motion), whereas the observed seismicity and laboratory data on fault strength suggest that the locking depth should be no greater than 10 to 15 km. The discrepancy is explained by the viscoelastic coupling model which accounts for the viscoelastic response of the lower crust. Thus the broad distribution of deformation observed across the big bend segment can be largely associated with the San Andreas fault itself, not subsidiary faults distributed throughout the region. The Working Group on California Earthquake Probabilities [1995] in using geodetic data to estimate the seismic risk in southern California has assumed that strain accumulated off the San Andreas fault is released by earthquakes located off the San Andreas fault. Thus they count the San Andreas contribution to total seismic moment accumulation more than once, leading to an overestimate of the seismicity for magnitude 6 and greater earthquakes in their Type C zones.

Geomorphology of the Southern Gulf of California Seafloor

NASA Astrophysics Data System (ADS)

Eakins, B. W.; Lonsdale, P. F.; Fletcher, J. M.; Ledesma, J. V.

2004-12-01

A Spring 2004 multibeam sonar survey defined the seafloor geomorphology of the southern part of Gulf of California and the intersection of the East Pacific Rise with the North American continent. Survey goals included mapping structural patterns formed during the rifting that opened the Gulf and identifying the spatial transition from continental rifting to seafloor spreading. Multibeam sonar imagery, augmented with archival data and a subaerial DEM of Mexico, illuminates the principal features of this boundary zone between obliquely diverging plates: (i) active and inactive oceanic risecrests within young oceanic basins that are rich in evidence for off-axis magmatic eruption and intrusion; (ii) transforms with pull-apart basins and transpressive ridges along shearing continental margins and within oceanic crust; (iii) orphaned blocks of continental crust detached from sheared and rifted continental margins; and (iv) young, still-extending continental margins dissected by submarine canyons that in many cases are deeply drowned river valleys. Many of the canyons are conduits for turbidity currents that feed deep-sea fans on oceanic and subsided continental crust, and channel sediment to spreading axes, thereby modifying the crustal accretion process. We present a series of detailed bathymetric and seafloor reflectivity maps of this MARGINS Rupturing Continental Lithosphere focus site illustrating geomorphologic features of the southern part of the Gulf, from Guaymas Basin to the Maria Magdalena Rise.

Incipient Evolution of the Eastern California Shear Zone through a Transpressional Zone along the San Andreas Fault in the San Bernardino Mountains, California

NASA Astrophysics Data System (ADS)

Cochran, W. J.; Spotila, J. A.

2017-12-01

Measuring long-term accumulation of strike-slip displacements and transpressional uplift is difficult where strain is accommodated across wide shear zones, as opposed to a single major fault. The Eastern California Shear Zone (ECSZ) in southern California accommodates dextral shear across several strike-slip faults, and is potentially migrating and cutting through a formerly convergent zone of the San Bernardino Mountains (SBM). The advection of crust along the San Andreas fault to the SE has forced these two tectonic regimes into creating a nexus of interacting strike-slip faults north of San Gorgonio Pass. These elements make this region ideal for studying complex fault interactions, evolving fault geometries, and deformational overprinting within a wide shear zone. Using high-resolution topography and field mapping, this study aims to test whether diffuse, poorly formed strike-slip faults within the uplifted SBM block are nascent elements of the ECSZ. Topographic resolution of ≤ 1m was achieved using both lidar and UAV surveys along two Quaternary strike-slip faults, namely the Lake Peak fault and Lone Valley faults. Although the Lone Valley fault cuts across Quaternary alluvium, the geomorphic expression is obscured, and may be the result of slow slip rates. In contrast, the Lake Peak fault is located high elevations north of San Gorgonio Peak in the SBM, and displaces Quaternary glacial deposits. The deposition of large boulders along the escarpment also obscures the apparent magnitude of slip along the fault. Although determining fault offset is difficult, the Lake Peak fault does display evidence for minor right-lateral displacement, where the magnitude of slip would be consistent with individual faults within the ECSZ (i.e. ≤ 1 mm/yr). Compared to the preservation of displacement along strike-slip faults located within the Mojave Desert, the upland region of the SBM adds complexity for measuring fault offset. The distribution of strain across the entire

Assessing estuarine biota in southern California

Treesearch

Kevin D. Lafferty

2005-01-01

In southern California, most estuarine wetlands are gone, and what little habitat remains is degraded. For this reason, it is often of interest to assess the condition of estuaries over time, such as when determining the success of a restoration project. To identify impacts or opportunities for restoration, we also may want to know how a particular estuary, or area...

Effectiveness of the California State Ban on the Sale of Caulerpa Species in Aquarium Retail Stores in Southern California

NASA Astrophysics Data System (ADS)

Diaz, Stephanie; Smith, Jayson R.; Zaleski, Susan F.; Murray, Steven N.

2012-07-01

The invasion of the aquarium strain of the green alga Caulerpa taxifolia and subsequent alteration of community structure in the Mediterranean Sea raised awareness of the potential for non-native seaweeds to impact coastal communities. An introduction of C. taxifolia in southern California in 2000, presumably from the release of aquarium specimens, cost ~7 million for eradication efforts. Besides C. taxifolia, other Caulerpa species being sold for aquarium use also may have the potential to invade southern Californian and U.S. waters. Surveys of the availability of Caulerpa species in southern California aquarium retail stores in 2000-2001 revealed that 26 of 50 stores sold at least one Caulerpa species (52 %) with seven stores selling C. taxifolia. In late 2001, California imposed a ban on the importation, sale, or possession of nine Caulerpa species; the City of San Diego expanded these regulations to include the entire genus. To determine the effectiveness of the California ban, we resurveyed Caulerpa availability at 43 of the 50 previously sampled retail stores in southern California in ~2006, ~4 years following the ban. Of the 43 stores, 23 sold Caulerpa (53 %) with four stores selling C. taxifolia. A χ2 test of frequency of availability before and after the California ban suggests that the ban has not been effective and that the aquarium trade continues to represent a potential vector for distributing Caulerpa specimens, including C. taxifolia. This study underscores the need for increased enforcement and outreach programs to increase awareness among the aquarium industry and aquarium hobbyists.

Effectiveness of the California state ban on the sale of Caulerpa species in aquarium retail stores in southern California.

PubMed

Diaz, Stephanie; Smith, Jayson R; Zaleski, Susan F; Murray, Steven N

2012-07-01

The invasion of the aquarium strain of the green alga Caulerpa taxifolia and subsequent alteration of community structure in the Mediterranean Sea raised awareness of the potential for non-native seaweeds to impact coastal communities. An introduction of C. taxifolia in southern California in 2000, presumably from the release of aquarium specimens, cost ~$7 million for eradication efforts. Besides C. taxifolia, other Caulerpa species being sold for aquarium use also may have the potential to invade southern Californian and U.S. waters. Surveys of the availability of Caulerpa species in southern California aquarium retail stores in 2000-2001 revealed that 26 of 50 stores sold at least one Caulerpa species (52 %) with seven stores selling C. taxifolia. In late 2001, California imposed a ban on the importation, sale, or possession of nine Caulerpa species; the City of San Diego expanded these regulations to include the entire genus. To determine the effectiveness of the California ban, we resurveyed Caulerpa availability at 43 of the 50 previously sampled retail stores in southern California in ~2006, ~4 years following the ban. Of the 43 stores, 23 sold Caulerpa (53 %) with four stores selling C. taxifolia. A χ(2) test of frequency of availability before and after the California ban suggests that the ban has not been effective and that the aquarium trade continues to represent a potential vector for distributing Caulerpa specimens, including C. taxifolia. This study underscores the need for increased enforcement and outreach programs to increase awareness among the aquarium industry and aquarium hobbyists.

Seafloor geology and benthic habitats, San Pedro Shelf, southern California

USGS Publications Warehouse

Wong, Florence L.; Dartnell, Peter; Edwards, Brian D.; Phillips, Eleyne L.

2012-01-01

Seafloor samples, videography, still photography, and real-time descriptions of geologic and biologic constituents at or near the seafloor of the San Pedro Shelf, southern California, advance the study of natural and man-made processes on this coastal area off the metropolitan Los Angeles area. Multibeam echo-sounder data collected by the U.S. Geological Survey in 1998 and 1999 guided sampling and camera work in 2004 resulting in a new seafloor character map that shows possible benthic habitats in much higher resolution (4- and 16-m pixels) than previously available. The seafloor is characterized by primarily muddy sand and sand with outcrops of Miocene and Pliocene bedrock along the Palos Verdes Fault Zone. Observed benthic populations indicate low abiotic complexity, low biotic complexity, and low biotic coverage. The data are provided for use in geographic information systems (GIS).

Land-Cover Trends of the Southern California Mountains Ecoregion

USGS Publications Warehouse

Soulard, Christopher E.; Raumann, Christian G.; Wilson, Tamara S.

2007-01-01

This report presents an assessment of land-use and land-cover (LU/LC) change in the Southern California Mountains ecoregion for the period 1973-2001. The Southern California Mountains is one of 84 Level-III ecoregions as defined by the U.S. Environmental Protection Agency (EPA). Ecoregions have served as a spatial framework for environmental resource management, denoting areas that contain a geographically distinct assemblage of biotic and abiotic phenomena including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The established Land Cover Trends methodology generates estimates of change for ecoregions using a probability sampling approach and change-detection analysis of thematic land-cover images derived from Landsat satellite imagery.

Groundwater quality in the Southern Sierra Nevada, California

USGS Publications Warehouse

Fram, Miranda S.; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Tehachapi-Cummings Valley and Kern River Valley basins and surrounding watersheds in the Southern Sierra Nevada constitute one of the study units being evaluated.

Petrogenesis of cataclastic rocks within the San Andreas fault zone of Southern California U.S.A.

NASA Astrophysics Data System (ADS)

Lawford Anderson, J.; Osborne, Robert H.; Palmer, Donald F.

1980-08-01

This paper petrologically characterizes cataclastic rocks derived from four sites within the San Andreas fault zone of southern California. In this area, the fault traverses an extensive plutonic and metamorphic terrane and the principal cataclastic rock formed at these upper crustal levels is unindurated gouge derived from a range of crystalline rocks including diorite, tonalite, granite, aplite, and pegmatite. The mineralogical nature of this gouge is decidedly different from the "clay gouge" reported by Wu (1975) for central California and is essentially a rock flour with a quartz, feldspar, biotite, chlorite, amphibole, epidote and oxide mineralogy representing the milled-down equivalent of the original rock. Clay development is minor (less than 4 wt. %) to nonexistent and is exclusively kaolinite. Alterations involve hematitic oxidation, chlorite alteration on biotite and amphibole, and local introduction of calcite. Electron microprobe analysis showed that in general the major minerals were not reequilibrated with the pressure—temperature regime imposed during cataclasis. Petrochemically, the form of cataclasis that we have investigated is largely an isochemical process. Some hydration occurs but the maximum amount is less than 2.2% added H 2O. Study of a 375 m deep core from a tonalite pluton adjacent to the fault showed that for Si, Al, Ti, Fe, Mg, Mn, K, Na, Li, Rb, and Ba, no leaching and/or enrichment occurred. Several samples experienced a depletion in Sr during cataclasis while lesser number had an enrichment of Ca (result of calcite veining). Texturally, the fault gouge is not dominated by clay-size material but consists largely of silt and fine sand-sized particles. An intriguing aspect of our work on the drill core is a general decrease in particulate size with depth (and confining pressure) with the predominate shifting sequentially from fine sand to silt-size material. The original fabric of these rocks is commonly not disrupted during the

Strike-slip faulting in the Inner California Borderlands, offshore Southern California.

NASA Astrophysics Data System (ADS)

Bormann, J. M.; Kent, G. M.; Driscoll, N. W.; Harding, A. J.; Sahakian, V. J.; Holmes, J. J.; Klotsko, S.; Kell, A. M.; Wesnousky, S. G.

2015-12-01

In the Inner California Borderlands (ICB), offshore of Southern California, modern dextral strike-slip faulting overprints a prominent system of basins and ridges formed during plate boundary reorganization 30-15 Ma. Geodetic data indicate faults in the ICB accommodate 6-8 mm/yr of Pacific-North American plate boundary deformation; however, the hazard posed by the ICB faults is poorly understood due to unknown fault geometry and loosely constrained slip rates. We present observations from high-resolution and reprocessed legacy 2D multichannel seismic (MCS) reflection datasets and multibeam bathymetry to constrain the modern fault architecture and tectonic evolution of the ICB. We use a sequence stratigraphy approach to identify discrete episodes of deformation in the MCS data and present the results of our mapping in a regional fault model that distinguishes active faults from relict structures. Significant differences exist between our model of modern ICB deformation and existing models. From east to west, the major active faults are the Newport-Inglewood/Rose Canyon, Palos Verdes, San Diego Trough, and San Clemente fault zones. Localized deformation on the continental slope along the San Mateo, San Onofre, and Carlsbad trends results from geometrical complexities in the dextral fault system. Undeformed early to mid-Pleistocene age sediments onlap and overlie deformation associated with the northern Coronado Bank fault (CBF) and the breakaway zone of the purported Oceanside Blind Thrust. Therefore, we interpret the northern CBF to be inactive, and slip rate estimates based on linkage with the Holocene active Palos Verdes fault are unwarranted. In the western ICB, the San Diego Trough fault (SDTF) and San Clemente fault have robust linear geomorphic expression, which suggests that these faults may accommodate a significant portion of modern ICB slip in a westward temporal migration of slip. The SDTF offsets young sediments between the US/Mexico border and the

Southern California landslides-an overview

USGS Publications Warehouse

,

2005-01-01

Southern California lies astride a major tectonic plate boundary defined by the San Andreas Fault and numerous related faults that are spread across a broad region. This dynamic tectonic environment has created a spectacular landscape of rugged mountains and steep-walled valleys that compose much of the region’s scenic beauty. Unfortunately, this extraordinary landscape also presents serious geologic hazards. Just as tectonic forces are steadily pushing the landscape upward, gravity is relentlessly tugging it downward. When gravity prevails, landslides can occur.

Fires in Southern California

NASA Technical Reports Server (NTRS)

2007-01-01

In what seemed like the blink of an eye, wildfires ignited in the paper-dry, drought-stricken vegetation of Southern California over the weekend of October 20, 2007, and exploded into massive infernos that forced hundreds of thousands of people to evacuate their communities. Driven by Santa Ana winds, fires grew thousands of acres in just one to two days. The fires sped down from the mountains into the outskirts of coastal cities, including San Diego. Dozens of homes have burned to the ground, and at least one person has died, according to local news reports. Several of the fires were burning completely out of control as of October 22. This image of the fires in California was captured at 1:55 p.m. U.S. Pacific Daylight Time on October 22, 2007. Places where MODIS detected actively burning fires are outlined in red. Thick streamers of smoke unfurl over the Pacific Ocean. The brownish plumes are clouds of dust. Fires northwest of Los Angeles seemed calmer at the time of this image than they were the previous day.

75 FR 26100 - Danger Zone, Pacific Ocean, Naval Base Coronado, Coronado, California

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-11

..., Pacific Ocean, Naval Base Coronado, Coronado, California AGENCY: U.S. Army Corps of Engineers, DoD. ACTION... Naval Base Coronado (NBC), in Coronado, San Diego County, California. The danger zone will provide..., Naval Base Coronado (NBC), has requested that the Corps establish a danger zone in the waters of the...

33 CFR 165.1105 - Security Zone: San Diego Bay, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Security Zone: San Diego Bay... Security Zone: San Diego Bay, California. (a) Location. (1) The following area is a security zone: The...″ N, Longitude 117°13′34.1″ W. (2) Because the area of this security zone is measured from the pier...

33 CFR 165.1105 - Security Zone: San Diego Bay, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Security Zone: San Diego Bay... Security Zone: San Diego Bay, California. (a) Location. (1) The following area is a security zone: The...″ N, Longitude 117°13′34.1″ W. (2) Because the area of this security zone is measured from the pier...

33 CFR 165.1105 - Security Zone: San Diego Bay, California.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone: San Diego Bay... Security Zone: San Diego Bay, California. (a) Location. (1) The following area is a security zone: The...″ N, Longitude 117°13′34.1″ W. (2) Because the area of this security zone is measured from the pier...

33 CFR 165.1105 - Security Zone: San Diego Bay, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zone: San Diego Bay... Security Zone: San Diego Bay, California. (a) Location. (1) The following area is a security zone: The...″ N, Longitude 117°13′34.1″ W. (2) Because the area of this security zone is measured from the pier...

33 CFR 165.1105 - Security Zone: San Diego Bay, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Security Zone: San Diego Bay... Security Zone: San Diego Bay, California. (a) Location. (1) The following area is a security zone: The...″ N, Longitude 117°13′34.1″ W. (2) Because the area of this security zone is measured from the pier...

Rayleigh phase velocities in the upper mantle of the Pacific-North American plate boundary in southern California

NASA Astrophysics Data System (ADS)

Escobar, L.; Weeraratne, D. S.; Kohler, M. D.

2013-05-01

The Pacific-North America plate boundary, located in Southern California, presents an opportunity to study a unique tectonic process that has been shaping the plate tectonic setting of the western North American and Mexican Pacific margin since the Miocene. This is one of the few locations where the interaction between a migrating oceanic spreading center and a subduction zone can be studied. The rapid subduction of the Farallon plate outpaced the spreading rate of the East Pacific Rise rift system causing it to be subducted beneath southern California and northern Mexico 30 Ma years ago. The details of microplate capture, reorganization, and lithospheric deformation on both the Pacific and North American side of this boundary is not well understood, but may have important implications for fault activity, stresses, and earthquake hazard analysis both onshore and offshore. We use Rayleigh waves recorded by an array of 34 ocean bottom seismometers deployed offshore southern California for a 12 month duration from August 2010 to 2011. Our array recorded teleseismic earthquakes at distances ranging from 30° to 120° with good signal-to-noise ratios for magnitudes Mw ≥ 5.9. The events exhibit good azimuthal distribution and enable us to solve simultaneously for Rayleigh wave phase velocities and azimuthal anisotropy. Fewer events occur at NE back-azimuths due to the lack of seismicity in central North America. We consider seismic periods between 18 - 90 seconds. The inversion technique considers non-great circle path propagation by representing the arriving wave field as two interfering plane waves. This takes advantage of statistical averaging of a large number of paths that travel offshore southern California and northern Mexico allowing for improved resolution and parameterization of lateral seismic velocity variations at lithospheric and sublithospheric depths. We present phase velocity results for periods sampling mantle structure down to 150 km depth along the

Geomorphic features off southern California as seen by GLORIA side-scan sonar system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, B.D.; Field, M.E.; Carlson, P.R.

1985-02-01

Approximately 165,000 km/sup 2/ of the sea floor off southern California was mapped during May 1984, as part of a USGS/IOS cooperative program to study the newly proclaimed Exclusive Economic Zone (EEZ) of the US Pacific margin. The area was insonified using the Geological Long-Range Inclined Asdic (GLORIA), a long-range side-scan sonar system. Images were corrected for water-column velocity anomalies, for along-track distortions caused by acoustic ray travel paths. A photomosaic of the overlapping sonographs has been compiled at a scale of 1:375,000. The basins of the inner California continental borderland are characterized by both sinuous channel and fan complexesmore » and by feathery acoustic patterns indicating active sediment transport. In contrast, outer borderland basins appear to be more sediment starved, exhibit large areas of sediment failure, and show significant structural influence. West of Patton Escarpment, the sonographs are dominated by acoustic patterns showing volcanic ridges and seamounts and by deposits of the Monterey and Arguello fans. Arguello fan, for example, exhibits multiple sinuous channels that have transported sediment 60 km south from the canyon mouth. These channels coalesce into a single 100-km long, westward-meandering channel that terminates in a 600-m deep box canyon. A zone of sediment failure is identifiable on the north levee of an upper fan channel. Tectonic trends associated with oceanic basement are highlighted by the terminus of the west-trending Murray Fracture Zone and by the prevailing northeast trend of volcanic ridge and seamount chains.« less

77 FR 15722 - Southern California Hook and Line Survey; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-16

... meeting to evaluate the Southern California Shelf Rockfish Hook and Line Survey which was designed to... and Line survey design and protocols; (2) examine the analytical methods used to generate rockfish... California Hook and Line Survey; Public Meeting AGENCY: National Marine Fisheries Service (NMFS), National...

Can Southern California Wildland Conflagrations be Stopped?

Treesearch

Clive M. Countryman

1974-01-01

In southern California, many fires start and burn under conditions that permit their control with little burned acreage and fire damage. In contrast, under other conditions of weather and topography, on a small group of fires, control effort is relatively ineffective; they become large and destructive. A major reason for these "conflagration fires" is the...

Santa Ana Winds and Fire Regimes of Southern California National Forests

NASA Astrophysics Data System (ADS)

Bendix, J.

2015-12-01

In Southern California, it has long been understood that foehn-type Santa Ana winds are an important factor in the occurrence of large wildfires. Although a variety of anecdotal observations and statistical analyses have confirmed the importance of these winds to wildfire, particularly in the Fall months when Santa Ana winds overlap with dry fuels from summer drought, many of the details of those winds' impacts on fire remain obscure. This paper uses data regarding individual fires from California's Fire and Resource Assessment Program database and a compilation of Santa Ana Wind days (SAW days) published by Abatzoglou et al. in 2013 to assess the relationship of Santa Ana winds to fire occurrence and size in Southern California. The analysis included 474 fires larger than 20 ha (~50 acres).that burned on the four Southern California national forests (Angeles, Cleveland, Los Padres and San Bernardino) between 1948 and 2010. Overall, just 10.3% of the fires started on SAW days, and 14.4% experienced at least one SAW day between start and containment dates. The impact of Santa Ana winds is greater, however, with increasing fire size. For fires > 4000 ha, 18.4% began on SAW days, with 30.4% experiencing at least one SAW day before containment. And 20% of fires > 20000 ha started on SAW days, with 50% including one or more SAW days. Fires beginning on SAW days were larger, with a mean of 6239 ha compared to 2150 ha for fires that began on non-SAW days. Only 2% of the fires that began on SAW days were started by lightning, suggesting that the impact of Santa Ana winds on Southern California fire regimes may be enhanced by humans' role in ignitions.

Spatiotemporal dynamics of the Southern California Asian citrus psyllid (Diaphorina citri) invasion.

PubMed

Bayles, Brett R; Thomas, Shyam M; Simmons, Gregory S; Grafton-Cardwell, Elizabeth E; Daugherty, Mathew P

2017-01-01

Biological invasions are governed by spatial processes that tend to be distributed in non-random ways across landscapes. Characterizing the spatial and temporal heterogeneities of the introduction, establishment, and spread of non-native insect species is a key aspect of effectively managing their geographic expansion. The Asian citrus psyllid (Diaphorina citri), a vector of the bacterium associated with huanglongbing (HLB), poses a serious threat to commercial and residential citrus trees. In 2008, D. citri first began expanding northward from Mexico into parts of Southern California. Using georeferenced D. citri occurrence data from 2008-2014, we sought to better understand the extent of the geographic expansion of this invasive vector species. Our objectives were to: 1) describe the spatial and temporal distribution of D. citri in Southern California, 2) identify the locations of statistically significant D. citri hotspots, and 3) quantify the dynamics of anisotropic spread. We found clear evidence that the spatial and temporal distribution of D. citri in Southern California is non-random. Further, we identified the existence of statistically significant hotspots of D. citri occurrence and described the anisotropic dispersion across the Southern California landscape. For example, the dominant hotspot surrounding Los Angeles showed rapid and strongly asymmetric spread to the south and east. Our study demonstrates the feasibility of quantitative invasive insect risk assessment with the application of a spatial epidemiology framework.

Spatiotemporal dynamics of the Southern California Asian citrus psyllid (Diaphorina citri) invasion

PubMed Central

Thomas, Shyam M.; Simmons, Gregory S.; Grafton-Cardwell, Elizabeth E.; Daugherty, Mathew P.

2017-01-01

Biological invasions are governed by spatial processes that tend to be distributed in non-random ways across landscapes. Characterizing the spatial and temporal heterogeneities of the introduction, establishment, and spread of non-native insect species is a key aspect of effectively managing their geographic expansion. The Asian citrus psyllid (Diaphorina citri), a vector of the bacterium associated with huanglongbing (HLB), poses a serious threat to commercial and residential citrus trees. In 2008, D. citri first began expanding northward from Mexico into parts of Southern California. Using georeferenced D. citri occurrence data from 2008–2014, we sought to better understand the extent of the geographic expansion of this invasive vector species. Our objectives were to: 1) describe the spatial and temporal distribution of D. citri in Southern California, 2) identify the locations of statistically significant D. citri hotspots, and 3) quantify the dynamics of anisotropic spread. We found clear evidence that the spatial and temporal distribution of D. citri in Southern California is non-random. Further, we identified the existence of statistically significant hotspots of D. citri occurrence and described the anisotropic dispersion across the Southern California landscape. For example, the dominant hotspot surrounding Los Angeles showed rapid and strongly asymmetric spread to the south and east. Our study demonstrates the feasibility of quantitative invasive insect risk assessment with the application of a spatial epidemiology framework. PMID:28278188

Deformation and Oil Migration Along the Active Newport-Inglewood Fault Zone, Southern California, USA

NASA Astrophysics Data System (ADS)

Sample, J. C.

2006-12-01

Deformation bands occur in an outcrop of a petroleum-bearing, sandstone-rich unit of the Monterey Formation along the active Newport-Inglewood fault zone (NIFZ), near Corona del Mar, California. The deformation bands likely developed in a damage zone associated with a strand of the NIFZ. The bands appear to have formed in poorly lithified sandstone. They are relatively oil-free whereas the matrix sandstone contains oil in pore space. The deformation bands acted as baffles to flow, but continuing deformation likely breached permeability barriers over time. Thus the bands did not completely isolate compartments from oil migration, but similar structures in the subsurface would likely slow the rate of production in reservoirs. The network of bands at Corona del Mar forms a mesh with band intersection lines lying parallel to the trend of the NIFZ (northwest). This geometry formed as continuing deformation in the NIFZ rotated early bands into unfavorable orientations for continuing deformation, and new bands formed at high angles to the first set. Permeability in this setting is likely to have been anisotropic, higher parallel to strike of the NIFZ and lower vertically and perpendicular to the strike of the fault zone. One unique type of deformation band found here formed by dilation and early oil migration along fractures, and consequent carbonate cementation along fracture margins. These are thin, planar zones of oil 1 - 2 mm thick sandwiched between parallel, carbonate-cemented, positively weathering ribs. These bands appear to represent early oil migration by hydrofracture. Based on crosscutting relationships between structures and cements, there are three distinct phases of oil migration: early migration along discrete hydrofractures; dominant pore migration associated with periodic breaching of deformation bands; and late migration along open fractures, some several centimeters in width. This sequence may be representative of migration histories along the NIFZ in

Common shrubs of chaparral and associated ecosystems of southern California

Treesearch

C. Eugene Conrad

1987-01-01

This Guide presents taxonomic keys based on vegetative features of 132 southern California shrub and subshrub species found in an area bounded by the southern part of the coast ranges, the north and east sides of the transverse and peninsular ranges, and Mexico. The keys are supported with instructions and an extensive glossary. Species discussion includes a brief...

Dispersal forcing of a southern California river plumes, based on field and remote sensing observations

USGS Publications Warehouse

Warrick, Jonathan A.; Mertes, Leal A.K.; Washburn, Libe; Siegel, David A.

2004-01-01

River plumes are important pathways of terrestrial materials entering the sea. In southern California, rivers are known to be the dominant source of littoral, shelf and basin sediment and coastal pollution, although a basic understanding of the dynamics of these river inputs does not exist. Here we evaluate forcing parameters of a southern California river plume using ship-based hydrographic surveys and satellite remote sensing measurements to provide the first insights of river dispersal dynamics in southern California. Our results suggest that plumes of the Santa Clara River are strongly influenced by river inertia, producing jet-like structures ~10 km offshore during annual recurrence (~two-year) flood events and ~30 km during exceptional (~10-year recurrence) floods. Upwelling-favorable winds may be strong following stormwater events and can alter dispersal pathways of thse plumes. Due to similar runoff relationships and other reported satellite observations, we hypothesize that interia-dominated dispersal may be an important characteristic of the small, mountainous rivers throughout southern California.

Spatial and Temporal Examination of Bivalve Communities in Several Estuaries of Southern California and Northern Baja California, MX

PubMed Central

Crooks, Jeffrey A.; Reyns, Nathalie B.

2016-01-01

A combination of historical bivalve surveys spanning 30–50 years and contemporary sampling were used to document the changes in bivalve community structure over time at four southern California and one northern Baja California estuaries. While there are limitations to the interpretation of historic data, we observed generally similar trends of reduced total bivalve species richness, losses of relatively large and/or deeper-dwelling natives, and gains of relatively small, surface dwelling introduced species across the southern California estuaries, despite fairly distinct bivalve communities. A nearly 50-year absence of bivalves from two wetlands surveyed in a Baja California estuary continued. A combination of site history and current characteristics (e.g., location, depth) likely contributes to maintenance of distinct communities, and both episodic and gradual environmental changes likely contribute to within-estuary temporal shifts (or absences). We highlight future research needed to determine mechanisms underlying patterns so that we can better predict responses of bivalve communities to future scenarios, including climate change and restoration. PMID:26840744

Two examples of earthquake- hazard reduction in southern California.

USGS Publications Warehouse

Kockelman, W.J.; Campbell, C.C.

1983-01-01

Because California is seismically active, planners and decisionmakers must try to anticipate earthquake hazards there and, where possible, to reduce the hazards. Geologic and seismologic information provides the basis for the necessary plans and actions. Two examples of how such information is used are presented. The first involves assessing the impact of a major earthquake on critical facilities in southern California, and the second involves strengthening or removing unsafe masonry buildings in the Los Angeles area. -from Authors

75 FR 28604 - Southern California Edison Company; Pacific Gas and Electric Company; San Diego Gas & Electric...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. EL10-66-000] Southern California Edison Company; Pacific Gas and Electric Company; San Diego Gas & Electric Company; Notice of... (2010), Southern California Edison Company, Pacific Gas and Electric Company, and San Diego Gas...

Impact of a Large San Andreas Fault Earthquake on Tall Buildings in Southern California

NASA Astrophysics Data System (ADS)

Krishnan, S.; Ji, C.; Komatitsch, D.; Tromp, J.

2004-12-01

In 1857, an earthquake of magnitude 7.9 occurred on the San Andreas fault, starting at Parkfield and rupturing in a southeasterly direction for more than 300~km. Such a unilateral rupture produces significant directivity toward the San Fernando and Los Angeles basins. The strong shaking in the basins due to this earthquake would have had a significant long-period content (2--8~s). If such motions were to happen today, they could have a serious impact on tall buildings in Southern California. In order to study the effects of large San Andreas fault earthquakes on tall buildings in Southern California, we use the finite source of the magnitude 7.9 2001 Denali fault earthquake in Alaska and map it onto the San Andreas fault with the rupture originating at Parkfield and proceeding southward over a distance of 290~km. Using the SPECFEM3D spectral element seismic wave propagation code, we simulate a Denali-like earthquake on the San Andreas fault and compute ground motions at sites located on a grid with a 2.5--5.0~km spacing in the greater Southern California region. We subsequently analyze 3D structural models of an existing tall steel building designed in 1984 as well as one designed according to the current building code (Uniform Building Code, 1997) subjected to the computed ground motion. We use a sophisticated nonlinear building analysis program, FRAME3D, that has the ability to simulate damage in buildings due to three-component ground motion. We summarize the performance of these structural models on contour maps of carefully selected structural performance indices. This study could benefit the city in laying out emergency response strategies in the event of an earthquake on the San Andreas fault, in undertaking appropriate retrofit measures for tall buildings, and in formulating zoning regulations for new construction. In addition, the study would provide risk data associated with existing and new construction to insurance companies, real estate developers, and

Strain accumulation in southern California, 1973-1980.

USGS Publications Warehouse

Savage, J.C.; Prescott, W.H.; Lisowski, M.; King, N.E.

1981-01-01

Frequent surveys of seven trilateration networks in southern California over the interval 1973-1980 suggest that a regional increment in strain may have occurred in 1978-1979. Prior to 1978 and after late 1979 the strain accumulation has been predominantly a uniaxial north-south compression. This secular trend was interrupted sometime in 1978-1979 by an increment in both north-south and east-west extension in five of the seven networks. The onset of this change appears to have occurred first in the networks farthest south. The changes occurred without any unusual seismicity within the networks, but the overall seismicity in southern California was unusually low prior to and has been unusually high since the occurrence. The average principal strain rates for the seven networks in the 1973-1980 interval are 0.17 mu strain/yr north- south contraction and 0.08 mu strain/yr east-west extension. Although the observed increment in strain could be related to unidentified systematic error in the measuring system, a careful review of the measurements and comparisons with three other measuring systems reveal no appreciable cumulative systematic error. -Authors

A vegetation classification system applied to southern California

Treesearch

Timothy E. Paysen; Jeanine A. Derby; Hugh Black; Vernon C. Bleich; John W. Mincks

1980-01-01

A classification system for use in describing vegetation has been developed and is being applied to southern California. It is based upon a hierarchical stratification of vegetation, using physiognomic and taxonomic criteria. The system categories are Formation, Subformation. Series, Association, and Phase. Formations, Subformations, and Series have been specified for...

Tectonic Tremor along the San Jacinto Fault Zone near Anza, California

NASA Astrophysics Data System (ADS)

Brown, J. R.

2013-12-01

In several tectonic settings where it is observed, low frequency tremor is proven as a useful tool to probe slow fault slip at depth (e.g., southwest Japan, Cascadia, Parkfield). However, tremor is difficult to detect due to its long durations and low amplitudes close to the noise band. This is particularly true in southern California where cultural noise sources are both spatially and temporally pervasive. Visually scanning continuous seismic recordings of the Southern California Seismic Network from 2001-2011 we find three pervasive occurrences of tremor: fall 2001, summer 2005 and summer 2010. In this presentation we focus on our analysis of the summer 2010 tremors on account of the enhanced instrumentation from the EarthScope Plate Boundary Observatory. During summer 2010 we detect ~240 hours of tremor-like signals in vicinity of the San Jacinto fault zone (SJFZ) near Anza. Visual inspection of continuous recordings up to 100 km northeast and southwest of the SJFZ do not record tremor-like signals indicating the source is both weak and local. Tremor is discriminated from other noise sources by calculating their spectral shapes to assure the signals are distinct from local noise sources and earthquakes. Similar to tremor spectra in other settings, the tremor signals in vicinity of the SJFZ are spectrally flat up to 9 Hz. In order to characterize the tremor source, we employ a combination of running autocorrelation and matched-filter techniques to detect and locate low frequency earthquakes (LFE) along the SJFZ one hour at a time. The autocorrelation of the north and vertical components of 14 stations detects over 13500 LFEs. We identify S-wave arrivals using the cross-correlation of 6 s windows for event pairs using the north component. Preliminary analysis of S-waves reveals a localized swarm of LFE epicenters extending 5 to 10 km SE of the Anza Gap with a horizontal error of +/- 4 km. Tremor depths are poorly constrained due to the lack of clear P

Fault zone characteristics and basin complexity in the southern Salton Trough, California

USGS Publications Warehouse

Persaud, Patricia; Ma, Yiran; Stock, Joann M.; Hole, John A.; Fuis, Gary S.; Han, Liang

2016-01-01

Ongoing oblique slip at the Pacific–North America plate boundary in the Salton Trough produced the Imperial Valley (California, USA), a seismically active area with deformation distributed across a complex network of exposed and buried faults. To better understand the shallow crustal structure in this region and the connectivity of faults and seismicity lineaments, we used data primarily from the Salton Seismic Imaging Project to construct a three-dimensional P-wave velocity model down to 8 km depth and a velocity profile to 15 km depth, both at 1 km grid spacing. A VP = 5.65–5.85 km/s layer of possibly metamorphosed sediments within, and crystalline basement outside, the valley is locally as thick as 5 km, but is thickest and deepest in fault zones and near seismicity lineaments, suggesting a causative relationship between the low velocities and faulting. Both seismicity lineaments and surface faults control the structural architecture of the western part of the larger wedge-shaped basin, where two deep subbasins are located. We estimate basement depths, and show that high velocities at shallow depths and possible basement highs characterize the geothermal areas.

33 CFR 165.1108 - Security Zones; Cruise Ships, Port of San Diego, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., Port of San Diego, California. 165.1108 Section 165.1108 Navigation and Navigable Waters COAST GUARD... § 165.1108 Security Zones; Cruise Ships, Port of San Diego, California. (a) Definition. “Cruise ship” as... or at a port of call in the San Diego port. (b) Location. The following areas are security zones: All...

33 CFR 165.1108 - Security Zones; Cruise Ships, Port of San Diego, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., Port of San Diego, California. 165.1108 Section 165.1108 Navigation and Navigable Waters COAST GUARD... § 165.1108 Security Zones; Cruise Ships, Port of San Diego, California. (a) Definition. “Cruise ship” as... or at a port of call in the San Diego port. (b) Location. The following areas are security zones: All...

33 CFR 165.1108 - Security Zones; Cruise Ships, Port of San Diego, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Port of San Diego, California. 165.1108 Section 165.1108 Navigation and Navigable Waters COAST GUARD... § 165.1108 Security Zones; Cruise Ships, Port of San Diego, California. (a) Definition. “Cruise ship” as... or at a port of call in the San Diego port. (b) Location. The following areas are security zones: All...

33 CFR 165.1108 - Security Zones; Cruise Ships, Port of San Diego, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., Port of San Diego, California. 165.1108 Section 165.1108 Navigation and Navigable Waters COAST GUARD... § 165.1108 Security Zones; Cruise Ships, Port of San Diego, California. (a) Definition. “Cruise ship” as... or at a port of call in the San Diego port. (b) Location. The following areas are security zones: All...

Tectonic deformation in southern California

NASA Technical Reports Server (NTRS)

Jackson, David D.

1993-01-01

Our objectives were to use modem geodetic data, especially those derived from space techniques like Very Long Baseline Interferometry (VLBI), Satellite Laser Ranging (SLR), and the Global Positioning System (GPS) to infer crustal deformation in southern California and relate it to plate tectonics and earthquake hazard. To do this, we needed to collect some original data, write computer programs to determine positions of survey markers from geodetic observables, interpret time dependent positions in terms of velocity and earthquake caused episodic displacements, and construct a model to explain these velocities and displacements in terms of fault slip and plate movements.

Population genetic structure of the round stingray Urobatis halleri (Elasmobranchii: Rajiformes) in southern California and the Gulf of California

PubMed Central

Plank, S. M.; Lowe, C. G.; Feldheim, K. A.; Wilson, R. R.; Brusslan, J. A.

2017-01-01

The round stingray, Urobatis halleri, is a viviparous elasmobranch that inhabits inshore, benthic habitats ranging from the western U.S.A. to Panama. The population genetic structure of this species was inferred with seven polymorphic microsatellite loci in samples collected at three sites in coastal southern California, one near Santa Catalina Island, California and one in the eastern Gulf of California. Urobatis halleri is relatively common, but little is known of its movement patterns or population structure. Small FST values (−0·0017 to 0·0005) suggested little structure among coastal populations of southern and Baja California. The population sampled at Santa Catalina Island, which is separated by a deep-water channel from the coastal sites, however, was significantly divergent (large FST, 0·0251) from the other populations, suggesting low connectivity with coastal populations. The Santa Catalina Island population also had the lowest allele richness and lowest average heterozygosity, suggesting recent population bottlenecks in size. PMID:20646159

Differentiation of Secular and Postseismic Deformation in the Mojave Shear Zone in Southern California and Inference of Lithospheric Rheology

NASA Astrophysics Data System (ADS)

Shen, Z.; Liu, S.; Burgmann, R.

2015-12-01

The 1992 Mw 7.3 Landers and 1999 Mw7.1 Hector Mine earthquakes struck the Eastern California Shear Zone (ECSZ) in the Mojave Desert, Southern California. Coseismic and postseismic deformation from these events affect efforts to use Global Positioning System (GPS) observations collected since these events to establish a secular surface velocity field, especially in the near field of the coseismic ruptures. We devise block motion models constrained by both historical pre-Landers triangulation and trilateration observations and post-Landers GPS measurements to recover the secular deformation field and differentiate the postseismic transients in the Mojave region. Postseismic transients are found to remain in various "interseismic" GPS velocity solutions in the form of 2-3 mm/yr excess right-lateral shear across the Landers and Hector Mine coseismic ruptures [Liu et al., 2015 JGR]. Postseismic GPS time series differentiated from the secular velocity field reveal enduring late-stage transient motions in the near field of the coseismic ruptures. Using the postseismic time series data as model constraints, we develop postseismic deformation model invoking afterlip on faults and viscoelastic relaxation in the lower crust and upper mantle. A Burgers body material and a Maxwell material are assumed for the lower crust and upper mantle respectively. Our preliminary modeling result, constrained using GPS time series data from the SCEC Crustal Motion Map 4.0 (covering the time period of 1992-2004), reveals that both the long-term viscosities for the lower crust and upper mantle are on the order of e+19 Pa-s. This finding differs significantly from the "Crème Brulee" model predictions about the rheological structure of the lower crust and upper mantle, in which the lower crust has a substantially higher viscosity. We are incorporating more GPS time series data into our model, particularly the ones from continuous sites of the Plate Boundary Observatory network with post-2004

AmeriFlux US-SCw Southern California Climate Gradient - Pinyon/Juniper Woodland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Mike

This is the AmeriFlux version of the carbon flux data for the site US-SCw Southern California Climate Gradient - Pinyon/Juniper Woodland. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of six Southern California Climate Gradient flux towers operated along an elevation gradient (sites are US-SCg, US-SCs, US-SCf, US-SCw, US-SCc, US-SCd). This site is a Pinyon Juniper woodland with trees that are at least 150 years old, and ephemeral herbaceous cover following winter or spring rains. The site has experienced repeated drought during the record and roughly 50% Pinyon mortality over the last decade. Amore » nearby tower site (US-SCc) burned in a 1994 wildfire; comparisons between US-SCw and US-SCc provide a measure of the effects of the 1994 on land-atmosphere exchange.« less

A kinematic model for the evolution of the Eastern California Shear Zone and Garlock Fault, Mojave Desert, California

NASA Astrophysics Data System (ADS)

Dixon, Timothy H.; Xie, Surui

2018-07-01

The Eastern California shear zone in the Mojave Desert, California, accommodates nearly a quarter of Pacific-North America plate motion. In south-central Mojave, the shear zone consists of six active faults, with the central Calico fault having the fastest slip rate. However, faults to the east of the Calico fault have larger total offsets. We explain this pattern of slip rate and total offset with a model involving a crustal block (the Mojave Block) that migrates eastward relative to a shear zone at depth whose position and orientation is fixed by the Coachella segment of the San Andreas fault (SAF), southwest of the transpressive "big bend" in the SAF. Both the shear zone and the Garlock fault are assumed to be a direct result of this restraining bend, and consequent strain redistribution. The model explains several aspects of local and regional tectonics, may apply to other transpressive continental plate boundary zones, and may improve seismic hazard estimates in these zones.

Ciguatera fish poisoning. A southern California epidemic.

PubMed Central

Barton, E D; Tanner, P; Turchen, S G; Tunget, C L; Manoguerra, A; Clark, R F

1995-01-01

Ciguatera fish poisoning results from the bioconcentration of a variety of toxins produced by marine dinoflagellates. Signs and symptoms vary widely, but it usually presents as gastrointestinal and neurologic complaints beginning shortly after the ingestion of fish containing the toxins. Symptoms may persist for months and sometimes even years. Although cases have been reported throughout the United States, epidemics are most common along tropical and subtropical coasts and usually involve the ingestion of large carnivorous fish. We review the literature and report the first epidemic of 25 cases of ciguatera fish poisoning presenting to area hospitals in Southern California that were successfully tracked by the Department of Health Services and isolated to fish caught off the coast of Baja California, Mexico. Images Figure 1. PMID:7667980

The Plate Boundary Observatory Student Field Assistant Program in Southern California

NASA Astrophysics Data System (ADS)

Seider, E. L.

2007-12-01

Each summer, UNAVCO hires students as part of the Plate Boundary Observatory (PBO) Student Field Assistant Program. PBO, the geodetic component of the NSF-funded EarthScope project, involves the reconnaissance, permitting, installation, documentation, and maintenance of 880 permanent GPS stations in five years. During the summer 2007, nine students from around the US and Puerto Rico were hired to assist PBO engineers during the busy summer field season. From June to September, students worked closely with PBO field engineers to install and maintain permanent GPS stations in all regions of PBO, including Alaska. The PBO Student Field Assistant Program provides students with professional hands-on field experience as well as continuing education in the geosciences. It also gives students a glimpse into the increasing technologies available to the science community, the scope of geophysical research utilizing these technologies, and the field techniques necessary to complete this research. Students in the PBO Field Assistant Program are involved in all aspects of GPS support, including in-warehouse preparation and in-field installations and maintenance. Students are taught practical skills such as drilling, wiring, welding, hardware configuration, documentation, and proper field safety procedures needed to construct permanent GPS stations. These real world experiences provide the students with technical and professional skills that are not always available to them in a classroom, and will benefit them greatly in their future studies and careers. The 2007 summer field season in Southern California consisted of over 35 GPS permanent station installations. To date, the Southern California region of PBO has installed over 190 GPS stations. This poster presentation will highlight the experiences gained by the Southern California student field assistants, while supporting PBO- Southern California GPS installations in the Mohave Desert and the Inyo National Forest.

Products and Services Available from the Southern California Earthquake Data Center (SCEDC) and the Southern California Seismic Network (SCSN)

NASA Astrophysics Data System (ADS)

Yu, E.; Chen, S.; Chowdhury, F.; Bhaskaran, A.; Hutton, K.; Given, D.; Hauksson, E.; Clayton, R. W.

2009-12-01

The SCEDC archives continuous and triggered data from nearly 3000 data channels from 375 SCSN recorded stations. The SCSN and SCEDC process and archive an average of 12,000 earthquakes each year, contributing to the southern California earthquake catalog that spans from 1932 to present. The SCEDC provides public, searchable access to these earthquake parametric and waveform data through its website www.data.scec.org and through client applications such as STP, NETDC and DHI. New data products: ● The SCEDC is distributing synthetic waveform data from the 2008 ShakeOut scenario (Jones et al., USGS Open File Rep., 2008-1150) and (Graves et al. 2008; Geophys. Res. Lett.) This is a M 7.8 earthquake on the southern San Andreas fault. Users will be able to download 40 sps velocity waveforms in SAC format from the SCEDC website. The SCEDC is also distributing synthetic GPS data (Crowell et al., 2009; Seismo. Res. Letters.) for this scenario as well. ● The SCEDC has added a new web page to show the latest tomographic model of Southern California. This model is based on Tape et al., 2009 Science. New data services: ● The SCEDC is exporting data in QuakeML format. This is an xml format that has been adopted by the Advanced National Seismic System (ANSS). This data will also be available as a web service. ● The SCEDC is exporting data in StationXML format. This is an xml format created by the SCEDC and adopted by ANSS to fully describe station metadata. This data will also be available as a web service. ● The stp 1.6 client can now access both the SCEDC and the Northern California Earthquake Data Center (NCEDC) earthquake and waveform archives. In progress - SCEDC to distribute 1 sps GPS data in miniSEED format: ● As part of a NASA Advanced Information Systems Technology project in collaboration with Jet Propulsion Laboratory and Scripps Institution of Oceanography, the SCEDC will receive real time 1 sps streams of GPS displacement solutions from the California

Circulation and multiple-scale variability in the Southern California Bight

NASA Astrophysics Data System (ADS)

Dong, Changming; Idica, Eileen Y.; McWilliams, James C.

2009-09-01

The oceanic circulation in the Southern California Bight (SCB) is influenced by the large-scale California Current offshore, tropical remote forcing through the coastal wave guide alongshore, and local atmospheric forcing. The region is characterized by local complexity in the topography and coastline. All these factors engender variability in the circulation on interannual, seasonal, and intraseasonal time scales. This study applies the Regional Oceanic Modeling System (ROMS) to the SCB circulation and its multiple-scale variability. The model is configured in three levels of nested grids with the parent grid covering the whole US West Coast. The first child grid covers a large southern domain, and the third grid zooms in on the SCB region. The three horizontal grid resolutions are 20 km, 6.7 km, and 1 km, respectively. The external forcings are momentum, heat, and freshwater flux at the surface and adaptive nudging to gyre-scale SODA reanalysis fields at the boundaries. The momentum flux is from a three-hourly reanalysis mesoscale MM5 wind with a 6 km resolution for the finest grid in the SCB. The oceanic model starts in an equilibrium state from a multiple-year cyclical climatology run, and then it is integrated from years 1996 through 2003. In this paper, the 8-year simulation at the 1 km resolution is analyzed and assessed against extensive observational data: High-Frequency (HF) radar data, current meters, Acoustic Doppler Current Profilers (ADCP) data, hydrographic measurements, tide gauges, drifters, altimeters, and radiometers. The simulation shows that the domain-scale surface circulation in the SCB is characterized by the Southern California Cyclonic Gyre, comprised of the offshore equatorward California Current System and the onshore poleward Southern California Countercurrent. The simulation also exhibits three subdomain-scale, persistent ( i.e., standing), cyclonic eddies related to the local topography and wind forcing: the Santa Barbara Channel Eddy

Climate, Santa Ana Winds and Autumn Wildfires in Southern California

NASA Astrophysics Data System (ADS)

Westerling, Anthony L.; Cayan, Daniel R.; Brown, Timothy J.; Hall, Beth L.; Riddle, Laurence G.

2004-08-01

Wildfires periodically burn large areas of chaparral and adjacent woodlands in autumn and winter in southern California. These fires often occur in conjunction with Santa Ana weather events, which combine high winds and low humidity, and tend to follow a wet winter rainy season. Because conditions fostering large fall and winter wildfires in California are the result of large-scale patterns in atmospheric circulation, the same dangerous conditions are likely to occur over a wide area at the same time. Furthermore, over a century of watershed reserve management and fire suppression have promoted fuel accumulations, helping to shape one of the most conflagration-prone environments in the world. Combined with a complex topography and a large human population, southern Californian ecology and climate pose a considerable physical and societal challenge to fire management.

Spring migration and summer destinations of northern pintails from the coast of southern California

USGS Publications Warehouse

Miller, Michael R.; Takekawa, John Y.; Battaglia, Daniel S.; Golightly, Richard T.; Perry, William M.

2010-01-01

To examine pathways, timing, and destinations during migration in spring, we attached satellite-monitored transmitters (platform transmitting terminals) to 10 northern pintails (Anas acuta) during February 2001, at Point Mugu, Ventura County, California. This is a wintering area on the southern coast of California. We obtained locations from five adult males and three adult females every 3rd day through August. Average date of departure from the wintering area was 15 March (SE  =  3 days). We documented extended stopovers of ≥30 days for several northern pintails that could have accommodated nesting attempts (San Joaquin Valley, southwestern Montana, southern Alberta, north-central Nevada) or post-nesting molt (eastern Oregon, south-central Saskatchewan, northern Alaska, central Alberta). Wintering northern pintails from the southern coast of California used a wide range of routes, nesting areas, and schedules during migration in spring, which was consistent with the larger, wintering population in the Central Valley of California. Therefore, conservation of habitat that is targeted at stopover, nesting, and molting areas will benefit survival and management of both wintering populations.

Equatorial origin for Lower Jurassic radiolarian chert in the Franciscan Complex, San Rafael Mountains, southern California

USGS Publications Warehouse

Hagstrum, J.T.; Murchey, B.L.; Bogar, R.S.

1996-01-01

Lower Jurassic radiolarian chert sampled at two localities in the San Rafael Mountains of southern California (???20 km north of Santa Barbara) contains four components of remanent magnetization. Components A, B???, and B are inferred to represent uplift, Miocene volcanism, and subduction/accretion overprint magnetizations, respectively. The fourth component (C), isolated between 580?? and 680??C, shows a magnetic polarity stratigraphy and is interpreted as a primary magnetization acquired by the chert during, or soon after, deposition. Both sequences are late Pliensbachian to middle Toarcian in age, and an average paleolatitude calculated from all tilt-corrected C components is 1?? ?? 3?? north or south. This result is consistent with deposition of the cherts beneath the equatorial zone of high biologic productivity and is similar to initial paleolatitudes determined for chert blocks in northern California and Mexico. This result supports our model in which deep-water Franciscan-type cherts were deposited on the Farallon plate as it moved eastward beneath the equatorial productivity high, were accreted to the continental margin at low paleolatitudes, and were subsequently distributed northward by strike-slip faulting associated with movements of the Kula, Farallon, and Pacific plates. Upper Cretaceous turbidites of the Cachuma Formation were sampled at Agua Caliente Canyon to determine a constraining paleolatitude for accretion of the Jurassic chert sequences. These apparently unaltered rocks, however, were found to be completely overprinted by the A component of magnetization. Similar in situ directions and demagnetization behaviors observed in samples of other Upper Cretaceous turbidite sequences in southern and Baja California imply that these rocks might also give unreliable results.

Recovery of the Chaparral Riparian Zone After Wildfire

Treesearch

Frank W. Davis; Edward A. Keller; Anuja Parikh; Joan Florsheim

1989-01-01

After the Wheeler Fire in southern California in July 1985, we monitored sediment deposition and vegetation recovery in a section of the severely burned chaparral riparian zone of the North Fork of Matilija Creek, near Ojai, California. Increased runoff was accompanied by low magnitude debris flows and fluvial transport of gravel, most of which was added to the channel...

How big is the Ocean Dead Zone off the Coast of California?

NASA Astrophysics Data System (ADS)

Hofmann, A. F.; Peltzer, E. T.; Walz, P. M.; Brewer, P. G.

2010-12-01

The term “Ocean Dead Zone”, generally referring to a zone that is devoid of aerobic marine life of value to humans, is now widely used in the press and scientific literature but it appears to be not universally defined. The global assessment and monitoring of ocean dead zones, however, is of high public concern due to the considerable economic value associated with impacted fisheries and with questions over the growth of these zones forced by climate change. We report on the existence of a zone at ~850m depth off Santa Monica, California where dissolved oxygen (DO) levels are 1 μmol/kg; an order of magnitude below any existing definition of an “Ocean Dead Zone”. ROV dives show the region to be visually devoid of all aerobic marine life. But how large is this dead zone, and how may its boundaries be defined? Without an accepted definition we cannot report this nor can we compare it to other dead zones reported elsewhere in the world. “Dead zones” are now assessed solely by DO levels. A multitude of values in different units are used (Fig 1), which are clearly not universally applicable. This seriously hampers an integrated global monitoring and management effort and frustrates the development of valid connections with climate change and assessment of the consequences. Furthermore, input of anthropogenic CO2 can also stress marine life. Recent work supported by classical data suggests that higher pCO2 influences the thermodynamic energy efficiency of oxic respiration (CH2O + O2 -> CO2 + H2O). The ratio pO2/pCO2, called the respiration index (RI), emerges as the critical variable, combining the impacts of warming on DO and rising CO2 levels within a single, well defined quantity. We advocate that future monitoring efforts report pO2 and pCO2 concurrently, thus making it possible to classify, monitor and manage “dead zones” within a standard reference system that may include, as with e.g, hurricanes, differing categories of intensity. Fig.1. A DO

Biomass and fuel characteristics of chaparral in southern California

Treesearch

J.C. Regelbrugge; S.G. Conard

2002-01-01

Knowledge of biomass components and fuel characteristics of southern California chaparral plant communities is important for planning prescribed fires, suppressing wildfires, managing the fire regime, and understanding the ecological interactions between fire and chaparral community development and succession. To improve our understanding of the relationship between...

Analysis of High Spatial, Temporal, and Directional Resolution Recordings of Biological Sounds in the Southern California Bight

DTIC Science & Technology

2012-09-30

tested in this research is that the evolution of unit structure and song characteristics in the population of transiting humpback whales in the Southern...behavior of transiting humpback whales in the Southern California Bight, b) the use of passive underwater acoustic techniques for improved habitat...man-made sounds on the calling behavior of transiting humpback whales in the Southern California Bight”. The main scientific hypothesis to be

33 CFR 165.1106 - San Diego Bay, California-safety zone.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false San Diego Bay, California-safety... Diego Bay, California—safety zone. (a) The waters of San Diego Bay enclosed by the following boundaries are a safety zone: From a point located on the boundary of Coast Guard Air Station San Diego...

33 CFR 165.1106 - San Diego Bay, California-safety zone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false San Diego Bay, California-safety... Diego Bay, California—safety zone. (a) The waters of San Diego Bay enclosed by the following boundaries are a safety zone: From a point located on the boundary of Coast Guard Air Station San Diego...

33 CFR 165.1106 - San Diego Bay, California-safety zone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false San Diego Bay, California-safety... Diego Bay, California—safety zone. (a) The waters of San Diego Bay enclosed by the following boundaries are a safety zone: From a point located on the boundary of Coast Guard Air Station San Diego...

33 CFR 165.1106 - San Diego Bay, California-safety zone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false San Diego Bay, California-safety... Diego Bay, California—safety zone. (a) The waters of San Diego Bay enclosed by the following boundaries are a safety zone: From a point located on the boundary of Coast Guard Air Station San Diego...

33 CFR 165.1106 - San Diego Bay, California-safety zone.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false San Diego Bay, California-safety... Diego Bay, California—safety zone. (a) The waters of San Diego Bay enclosed by the following boundaries are a safety zone: From a point located on the boundary of Coast Guard Air Station San Diego...

78 FR 64196 - Foreign-Trade Zone 3-San Francisco, California; Application for Subzone; Phillips 66 Company...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-28

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-89-2013] Foreign-Trade Zone 3--San Francisco, California; Application for Subzone; Phillips 66 Company; Rodeo, California An application has been submitted to the Foreign-Trade Zones (FTZ) Board by the City and County of San Francisco, grantee of FTZ 3...

High-Resolution Chirp and Mini-Sparker Seismic-Reflection Data From the Southern California Continental Shelf - Gaviota to Mugu Canyon

USGS Publications Warehouse

Sliter, Ray W.; Triezenberg, Peter J.; Hart, Patrick E.; Draut, Amy E.; Normark, William R.; Conrad, James E.

2008-01-01

The U.S. Geological Survey (USGS) collected high-resolution shallow seismic-reflection data in September, 2007, and June-July, 2008, from the continental shelf offshore of southern California between Gaviota and Mugu Canyon, in support of the California's State Waters Mapping Program. Data were acquired using SIG 2mille mini-sparker and Edgetech chirp 512 instruments aboard the R/V Zephyr (Sept. 2007) and R/V Parke Snavely (June-July 2008). The survey area spanned approximately 120 km of coastline, and included shore-perpendicular transects spaced 1.0-1.5 km apart that extended offshore to at least the 3-mile limit of State waters, in water depths ranging from 10 m near shore to 300 m near the offshore extent of Mugu and Hueneme submarine canyons. Subbottom acoustic penetration spanned tens to several hundred meters, variable by location. This report includes maps of the surveyed transects, linked to Google Earth software, as well as digital data files showing images of each transect in SEG-Y, JPEG, and TIFF formats. The images of sediment deposits, tectonic structure, and natural-gas seeps collected during this study provide geologic information that is essential to coastal zone and resource management at Federal, State and local levels, as well as to future research on the sedimentary, tectonic, and climatic record of southern California.

Marine Mammal Acoustic Monitoring and Habitat Investigation, Southern California Offshore Region

DTIC Science & Technology

2009-06-01

whales , baleen whales , odontocetes, SCORE Range , offshore southern California, CalCOFI, blue whale , humpback whale , fin whale , sea surface temperature...they have been visually and acoustically detected off California during those times of year (Forney and Barlow 1998 ; Norris et al. 1999; Oleson 2005...whereas blue whales were only rarely detected in early winter and late spring (Oleson et al. 2007). In summer, whale

Dissolved oxygen as a constraint on daytime deep scattering layer depth in the southern California current ecosystem

NASA Astrophysics Data System (ADS)

Netburn, Amanda N.; Anthony Koslow, J.

2015-10-01

Climate change-induced ocean deoxygenation is expected to exacerbate hypoxic conditions in mesopelagic waters off the coast of southern California, with potentially deleterious effects for the resident fauna. In order to understand the possible impacts that the oxygen minimum zone expansion will have on these animals, we investigated the response of the depth of the deep scattering layer (i.e., upper and lower boundaries) to natural variations in midwater oxygen concentrations, light levels, and temperature over time and space in the southern California Current Ecosystem. We found that the depth of the lower boundary of the deep scattering layer (DSL) is most strongly correlated with dissolved oxygen concentration, and irradiance and oxygen concentration are the key variables determining the upper boundary. Based on our correlations and published estimates of annual rates of change to irradiance level and hypoxic boundary, we estimated the corresponding annual rate of change of DSL depths. If past trends continue, the upper boundary is expected to shoal at a faster rate than the lower boundary, effectively widening the DSL under climate change scenarios. These results have important implications for the future of pelagic ecosystems, as a change to the distribution of mesopelagic animals could affect pelagic food webs as well as biogeochemical cycles.

Curie Depth Analysis of the Salton Sea Region, Southern California

NASA Astrophysics Data System (ADS)

Mickus, Kevin; Hussein, Musa

2016-02-01

Aeromagnetic data were analyzed to determine the bottom of magnetic bodies that might be related to the Curie point depth (CPD) by 2D spectral and 3D inversion methods within the Salton Trough and the surrounding region in southern California. The bottom of the magnetic bodies for 55 × 55 km windows varied in depth between 11 and 23 km in depth using 2D spectral methods. Since the 55 × 55 km square window may include both shallow and deep source, a 3D inversion method was used to provide better resolution of the bottom of the magnetic bodies. The 3D models indicate the depth to the bottom of the magnetic bodies varied between 5 and 23 km. Even though both methods produced similar results, the 3D inversion method produced higher resolution of the CPD depths. The shallowest depths (5-8 km) occur along and west of the Brawley Seismic Zone and the southwestern portion of the Imperial Valley. The source of these shallow CPD values may be related to geothermal systems including hydrothermal circulation and/or partially molten material. Additionally, shallow CPD depths (7-12 km) were found in a northwest-trending zone in the center of the Salton Trough. These depths coincide with previous seismic analyses that indicated a lower crustal low velocity region which is believed to be caused by partially molten material. Lower velocity zones in several regions may be related to fracturing and/or hydrothermal fluids. If the majority of these shallow depths are related to temperature, they are likely associated with the CPD, and the partially molten material extends over a wider zone than previously known. Greater depths within the Salton Trough coincide with the base of basaltic material and/or regions of intense metamorphism intruded by mafic material in the middle/lower crust.

Southern California Area Environmental Manpower and Training Needs Study.

ERIC Educational Resources Information Center

Kowalski, James A.

A survey was conducted to identify environmentally related jobs, the current employment need in these areas, the 5-year projection, and the current status of educational training programs to meet the employment needs for technicians or paraprofessionals within a five-county area of Southern California. The environmentally related occupations…

Biomass and fuel characteristics of chaparral in southern California

Treesearch

Jon C. Regelbrugge; Sue Conard

1998-01-01

Accurate estimates of biomass components and fuel characteristics of southern California chaparral plant communities are important for planning prescribed fires, suppressing wildfires, and for understanding the ecological interactions between fire and chaparral community development and succession. We have sampled chaparral biomass and fuels on a variety of sites as...

Isostatic Gravity Map with Geology of the Santa Ana 30' x 60' Quadrangle, Southern California

USGS Publications Warehouse

Langenheim, V.E.; Lee, Tien-Chang; Biehler, Shawn; Jachens, R.C.; Morton, D.M.

2006-01-01

This report presents an updated isostatic gravity map, with an accompanying discussion of the geologic significance of gravity anomalies in the Santa Ana 30 by 60 minute quadrangle, southern California. Comparison and analysis of the gravity field with mapped geology indicates the configuration of structures bounding the Los Angeles Basin, geometry of basins developed within the Elsinore and San Jacinto Fault zones, and a probable Pliocene drainage network carved into the bedrock of the Perris block. Total cumulative horizontal displacement on the Elsinore Fault derived from analysis of the length of strike-slip basins within the fault zone is about 5-12 km and is consistent with previously published estimates derived from other sources of information. This report also presents a map of density variations within pre-Cenozoic metamorphic and igneous basement rocks. Analysis of basement gravity patterns across the Elsinore Fault zone suggests 6-10 km of right-lateral displacement. A high-amplitude basement gravity high is present over the San Joaquin Hills and is most likely caused by Peninsular Ranges gabbro and/or Tertiary mafic intrusion. A major basement gravity gradient coincides with the San Jacinto Fault zone and marked magnetic, seismic-velocity, and isotopic gradients that reflect a discontinuity within the Peninsular Ranges batholith in the northeast corner of the quadrangle.

Spatial and Temporal Patterns of Chlorophyll Concentration in the Southern California Bight

NASA Astrophysics Data System (ADS)

Nezlin, Nikolay P.; McLaughlin, Karen; Booth, J. Ashley T.; Cash, Curtis L.; Diehl, Dario W.; Davis, Kristen A.; Feit, Adriano; Goericke, Ralf; Gully, Joseph R.; Howard, Meredith D. A.; Johnson, Scott; Latker, Ami; Mengel, Michael J.; Robertson, George L.; Steele, Alex; Terriquez, Laura; Washburn, Libe; Weisberg, Stephen B.

2018-01-01

Distinguishing between local, anthropogenic nutrient inputs and large-scale climatic forcing as drivers of coastal phytoplankton biomass is critical to developing effective nutrient management strategies. Here we assess the relative importance of these two drivers by comparing trends in chlorophyll-a between shallow coastal (0.1-16.5 km) and deep offshore (17-700 km) areas, hypothesizing that coastal regions influenced by anthropogenic nutrient inputs may have different spatial and temporal patterns in chlorophyll-a concentration from offshore regions where coastal inputs are less influential. Quarterly conductivity-temperature-depth (CTD) fluorescence measurements collected from three southern California continental shelf regions since 1998 were compared to chlorophyll-a data from the more offshore California Cooperative Fisheries Investigations (CalCOFI) program. The trends in the coastal zone were similar to those offshore, with a gradual increase of chlorophyll-a biomass and shallowing of its maximum layer since the beginning of observations, followed by chlorophyll-a declining and deepening from 2010 to present. An exception was the northern coastal part of SCB, where chlorophyll-a continued increasing after 2010. The long-term increase in chlorophyll-a prior to 2010 was correlated with increased nitrate concentrations in deep waters, while the recent decline was associated with deepening of the upper mixed layer, both linked to the low-frequency climatic cycles of the Pacific Decadal Oscillation and North Pacific Gyre Oscillation. These large-scale factors affecting the physical structure of the water column may also influence the delivery of nutrients from deep ocean outfalls to the euphotic zone, making it difficult to distinguish the effects of anthropogenic inputs on chlorophyll along the coast.

The spotted owl in southern and central coastal California

Treesearch

R.J. Gutiérrez; Douglas J. Tempel; M. Zachariah Peery

2017-01-01

Spotted owl populations found in southern and central coastal California have received much less attention than those inhabiting the Sierra Nevada because of economic (effect of habitat conservation measures on timber harvest) and social issues (community stability and desire for naturally functioning ecosystems). Yet there has been continued concern over the...

78 FR 33808 - Foreign-Trade Zone 50-Long Beach, California; Authorization of Production Activity; Panasonic...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-05

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-13-2013] Foreign-Trade Zone 50--Long Beach, California; Authorization of Production Activity; Panasonic Corporation of North America (Kitting of Consumer Electronics); Anaheim, California On January 29, 2013, the Board of Harbor Commissioners of the Port of Long...

33 CFR 334.961 - Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Island, California, naval danger zone off the northwest shore. 334.961 Section 334.961 Navigation and... RESTRICTED AREA REGULATIONS § 334.961 Pacific Ocean, San Clemente Island, California, naval danger zone off... regulations in this section shall be enforced by the commander, Naval Base, San Diego, California, and such...

Stratigraphic record of Pliocene-Pleistocene basin evolution and deformation within the Southern San Andreas Fault Zone, Mecca Hills, California

NASA Astrophysics Data System (ADS)

McNabb, James C.; Dorsey, Rebecca J.; Housen, Bernard A.; Dimitroff, Cassidy W.; Messé, Graham T.

2017-11-01

A thick section of Pliocene-Pleistocene nonmarine sedimentary rocks exposed in the Mecca Hills, California, provides a record of fault-zone evolution along the Coachella Valley segment of the San Andreas fault (SAF). Geologic mapping, measured sections, detailed sedimentology, and paleomagnetic data document a 3-5 Myr history of deformation and sedimentation in this area. SW-side down offset on the Painted Canyon fault (PCF) starting 3.7 Ma resulted in deposition of the Mecca Conglomerate southwest of the fault. The lower member of the Palm Spring Formation accumulated across the PCF from 3.0 to 2.6 Ma during regional subsidence. SW-side up slip on the PCF and related transpressive deformation from 2.6 to 2.3 Ma created a time-transgressive angular unconformity between the lower and upper members of the Palm Spring Formation. The upper member accumulated in discrete fault-bounded depocenters until initiation of modern deformation, uplift, and basin inversion starting at 0.7 Ma. Some spatially restricted deposits can be attributed to the evolution of fault-zone geometric complexities. However, the deformation events at ca. 2.6 Ma and 0.7 Ma are recorded regionally along 80 km of the SAF through Coachella Valley, covering an area much larger than mapped fault-zone irregularities, and thus require regional explanations. We therefore conclude that late Cenozoic deformation and sedimentation along the SAF in Coachella Valley has been controlled by a combination of regional tectonic drivers and local deformation due to dextral slip through fault-zone complexities. We further propose a kinematic link between the 2.6-2.3 Ma angular unconformity and a previously documented but poorly dated reorganization of plate-boundary faults in the northern Gulf of California at 3.3-2.0 Ma. This analysis highlights the potential for high-precision chronologies in deformed terrestrial deposits to provide improved understanding of local- to regional-scale structural controls on basin

Refining Southern California Geotherms Using Seismologic, Geologic, and Petrologic Constraints

NASA Astrophysics Data System (ADS)

Thatcher, W. R.; Chapman, D. S.; Allam, A. A.; Williams, C. F.

2017-12-01

Lithospheric deformation in tectonically active regions depends on the 3D distribution of rheology, which is in turn critically controlled by temperature. Under the auspices of the Southern California Earthquake Center (SCEC) we are developing a 3D Community Thermal Model (CTM) to constrain rheology and so better understand deformation processes within this complex but densely monitored and relatively well-understood region. The San Andreas transform system has sliced southern California into distinct blocks, each with characteristic lithologies, seismic velocities and thermal structures. Guided by the geometry of these blocks we use more than 250 surface heat-flow measurements to define 13 geographically distinct heat flow regions (HFRs). Model geotherms within each HFR are constrained by averages and variances of surface heat flow q0 and the 1D depth distribution of thermal conductivity (k) and radiogenic heat production (A), which are strongly dependent on rock type. Crustal lithologies are not always well known and we turn to seismic imaging for help. We interrogate the SCEC Community Velocity Model (CVM) to determine averages and variances of Vp, Vs and Vp/Vs versus depth within each HFR. We bound (A, k) versus depth by relying on empirical relations between seismic wave speed and rock type and laboratory and modeling methods relating (A, k) to rock type. Many 1D conductive geotherms for each HFR are allowed by the variances in surface heat flow and subsurface (A, k). An additional constraint on the lithosphere temperature field is provided by comparing lithosphere-asthenosphere boundary (LAB) depths identified seismologically with those defined thermally as the depth of onset of partial melting. Receiver function studies in Southern California indicate LAB depths that range from 40 km to 90 km. Shallow LAB depths are correlated with high surface heat flow and deep LAB with low heat flow. The much-restricted families of geotherms that intersect peridotite

Simulation of Orographically-Driven Precipitation in Southern California

NASA Astrophysics Data System (ADS)

Carpenter, T. M.; Georgakakos, K. P.

2008-12-01

The proximity of the Pacific Ocean to the Transverse and Peninsular Mountain Ranges of coastal Southern California may lead to significant, orographically-enhanced precipitation in the region. With abundant moisture, such as evidenced in Pineapple Express events or atmospheric rivers, this precipitation may lead to other hydrologic hazards as flash flooding, landslides or debris flows. Available precipitation observation networks are relatively sparse in the mountainous regions and often do not capture the spatial variation of these events with high resolution. This study aims to simulate the topographically-driven precipitation over Southern California with high spatial resolution using a simplified orographic precipitation model. The model employs potential theory flow to estimate steady state three-dimensional wind fields for given free stream velocity forcing winds, atmospheric moisture advection, and cloud and precipitation microphysics proposed by Kessler (1969). The advantage of this modeling set-up is the computational efficiency as compared to regional mesoscale models such as the MM5. For this application, the Southern California region, comprised of the counties of Santa Barbara, Ventura, Los Angeles, Orange, and San Diego, and portions of San Bernardino and Riverside counties, are modeled at a 3-km resolution. The orographic precipitation model is forced by free stream wind velocities given by the 700mb winds from the NCEP Reanalysis I dataset. Atmospheric moisture initial conditions are defined also by the NCEP Reanalysis I dataset, and updated 4x- daily with the available 6-hourly NCEP Reanalysis forcing. This paper presents a comparison of the simulated precipitation to observations for over a variety of spatial scales and over the historical wet season periods from October 2000 to April 2005. The comparison is made over several performance measurements including (a) the occurrence/non-occurrence of precipitation, (b) overall bias and correlation, (c

Is wetland mitigation successful in Southern California?

NASA Astrophysics Data System (ADS)

Cummings, D. L.; Rademacher, L. K.

2004-12-01

Wetlands perform many vital functions within their landscape position; they provide unique habitats for a variety of flora and fauna and they act as treatment systems for upstream natural and anthropogenic waste. California has lost an estimated 91% of its wetlands. Despite the 1989 "No Net Loss" policy and mitigation requirements by the regulatory agencies, the implemented mitigation may not be offsetting wetlands losses. The "No Net Loss" policy is likely failing for numerous reasons related to processes in the wetlands themselves and the policies governing their recovery. Of particular interest is whether these mitigation sites are performing essential wetlands functions. Specific questions include: 1) Are hydric soil conditions forming in mitigation sites; and, 2) are the water quality-related chemical transformations that occur in natural wetlands observed in mitigation sites. This study focuses on success (or lack of success) in wetlands mitigation sites in Southern California. Soil and water quality investigations were conducted in wetland mitigation sites deemed to be successful by vegetation standards. Observations of the Standard National Resource Conservation Service field indicators of reducing conditions were made to determine whether hydric soil conditions have developed in the five or more years since the implementation of mitigation plans. In addition, water quality measurements were performed at the inlet and outlet of these mitigation sites to determine whether these sites perform similar water quality transformations to natural wetlands within the same ecosystem. Water quality measurements included nutrient, trace metal, and carbon species measurements. A wetland location with minimal anthropogenic changes and similar hydrologic and vegetative features was used as a control site. All sites selected for study are within a similar ecosystem, in the interior San Diego and western Riverside Counties, in Southern California.

Strain accumulation across the Eastern California Shear Zone at latitude 36°30'N

USGS Publications Warehouse

Gan, Weijun; Svarc, Jerry L.; Savage, J.C.; Prescott, W.H.

2000-01-01

The motion of a linear array of monuments extending across the Eastern California Shear Zone (ECSZ) has been measured from 1994 to 1999 with the Global Positioning System. The linear array is oriented N54°E, perpendicular to the tangent to the local small circle drawn about the Pacific-North America pole of rotation, and the observed motion across the ECSZ is approximated by differential rotation about that pole. The observations suggest uniform deformation within the ECSZ (strike N23°W) (26 nstrain yr−1 extension normal to the zone and 39 nstrain yr−1 simple right-lateral shear across it) with no significant deformation in the two blocks (the Sierra Nevada mountains and southern Nevada) on either side. The deformation may be imposed by right-lateral slip at depth on the individual major fault systems within the zone if the slip rates are: Death Valley-Furnace Creek fault 3.2±0.9 mm yr−1, Hunter Mountain-Panamint Valley fault 3.3±1.6 mm yr−1, and Owens Valley fault 6.9±1.6 mm yr−1. However, this estimate of the slip rate on the Owens Valley fault is 3 times greater than the geologic estimate.

Microbiological monitoring of marine recreational waters in southern California.

PubMed

Schiff, K C; Weisberg, S B; Dorsey, J H

2001-01-01

An inventory was conducted to assess the number, type, spatial distribution, and costs of microbiological monitoring programs in southern California marine waters from Point Conception to the US/Mexico International Border. The location of each sampling site was determined using global positioning system (GPS), and estimates of geographic coverage were determined using geographic information system (GIS) techniques. Twenty-one programs conducted 87,007 tests annually at 576 sites in the study area. The largest number of sites was sampled in Orange County, whereas the largest number of analyses was performed in Los Angeles County because monitoring programs in this area focused on daily monitoring. Fifteen of the 21 programs were managed by National Pollutant Discharge Elimination System (NPDES) permitted sewage effluent dischargers who sampled both offshore and shoreline waters and typically tested for three indicator bacteria (total coliform, fecal coliform, and enterococcus). Their combined efforts comprised 82% of all of the microbiological indicator analyses conducted on an annual basis. Five of the remaining monitoring organizations were public health agencies, which typically focus their efforts on testing only total coliforms. Laboratory methodology also varied considerably, with NPDES permittees predominantly utilizing membrane filtration while public health agencies generally used multiple tube fermentation or premanufactured test kits. Nearly three quarters of all the effort expended in southern California occurred along the shoreline as opposed to offshore locations. Two thirds of this shoreline effort was focused on high-use sandy beaches and in proximity to perennial fresh-water outlets (storm drains and creeks). Most sampling occurred at a set of fixed sites that were revisited frequently, but only represented about 7% of the total shoreline. We estimated that roughly $3 million is spent annually on monitoring bathing water quality in southern

Smoke emissions from prescribed burning of southern California chaparral.

Treesearch

Colin C. Hardy; Jon C. Regelbrugge; David R. Teesdale

1996-01-01

This report characterizes smoke emissions from small-scale prescribed burns in southern California chaparral. In situ measurements of smoke emissions were made from 12 fires. Three replicate tests were performed in each of four distinct fuel and fire treatments common to vegetation management operations: a young and rigorous chamise-dominated stand; an old and decadent...

Selected Collective Bargaining Agreements of Southern California Two-Year Colleges.

ERIC Educational Resources Information Center

National Education Association, Washington, DC.

Collective bargaining agreements between 14 selected community colleges in southern California and their faculty associations are presented, representing contracts in effect in 1987. Contracts for the following colleges are included: Barstow College, Chaffey College, College of the Sequoias, El Camino College, Glendale Community College, Imperial…

Strength of plate coupling in the southern Ryukyu subduction zone

NASA Astrophysics Data System (ADS)

Doo, Wen-Bin; Lo, Chung-Liang; Wu, Wen-Nan; Lin, Jing-Yi; Hsu, Shu-Kun; Huang, Yin-Sheng; Wang, Hsueh-Fen

2018-01-01

Understanding the strength of a plate coupling is critical for assessing potential seismic and tsunamic hazards in subduction zones. The interaction between an overriding plate and the associated subducting plate can be used to evaluate the strength of plate coupling by examining the mantle lithospheric buoyancy. Here, we calculate the mantle lithosphere buoyancy across the northern portion of the southern Ryukyu subduction zone based on gravity modeling with the constraints from a newly derived P-wave seismic velocity model. The result indicates that the strength of the plate coupling in the study area is relatively strong, which is consistent with previous observations in the southernmost Ryukyu subduction zone. Because few large earthquakes (Mw > 7) have occurred in the southern Ryukyu subduction zone, a large amount of energy is locked and accumulated by plate coupling, that could be released in the near future.

Urban emission, Santa Ana wind, and fire sources of aerosol nitrogen in Southern California

NASA Astrophysics Data System (ADS)

Mackey, K. R.; Stragier, S.; Robledo, L.; Cat, L. A.; Czimczik, C. I.

2017-12-01

Southern California is a highly urbanized region surrounded by extensive areas of agriculture and wilderness. While emissions from fossil fuel combustion are a large source of aerosol NOx in urban areas, fires contribute considerable aerosol NOx and ammonium in undeveloped regions. Southern California also has frequent wildfires, particularly during dry Santa Ana wind events that occur periodically throughout the winter. To explore the relative contributions of these sources to aerosol nitrogen content, we collected aerosol samples over two years in Irvine, a city in Southern California approximately 6 km from the Pacific coast. Samples were analyzed for total nitrogen and carbon content and isotopic composition (δ15N and δ13C), and nitrate and ammonium content. Carbon content was higher and δ13C values were lower in the winter than the summer. The C/N ratios of two samples collected during a Santa Ana wind event in January of 2012 were particularly elevated (C/N of 22 and 30) relative to other samples (C/N 3-6). We found that ammonium comprised 35% of total aerosol N across samples (R2=0.65), and that the δ15N of aerosol nitrogen decreased logarithmically as the proportion of nitrate in the sample increased (R2=0.60). Aerosol deposition of bioavailable nitrate and ammonium from these sources may support primary productivity in Southern California's coastal waters, particularly during the winter months and El Nino periods when upwelled nutrient sources are limited.

Cruise report for A1-98-SC southern California Earthquake Hazards Project

USGS Publications Warehouse

Normark, William R.; Bohannon, Robert G.; Sliter, Ray; Dunhill, Gita; Scholl, David W.; Laursen, Jane; Reid, Jane A.; Holton, David

1999-01-01

The focus of the Southern California Earthquake Hazards project, within the Western Region Coastal and Marine Geology team (WRCMG), is to identify the landslide and earthquake hazards and related ground-deformation processes that can potentially impact the social and economic well-being of the inhabitants of the Southern California coastal region, the most populated urban corridor along the U.S. Pacific margin. The primary objective is to help mitigate the earthquake hazards for the Southern California region by improving our understanding of how deformation is distributed (spatially and temporally) in the offshore with respect to the onshore region. To meet this overall objective, we are investigating the distribution, character, and relative intensity of active (i.e., primarily Holocene) deformation within the basins and along the shelf adjacent to the most highly populated areas (see Fig. 1). In addition, the project will examine the Pliocene-Pleistocene record of how this deformation has shifted in space and time. The results of this study should improve our knowledge of shifting deformation for both the long-term (105 to several 106 yr) and short-term (<50 ky) time frames and enable us to identify actively deforming structures that may constitute current significant seismic hazards.

76 FR 37646 - Safety Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, Lake Tahoe, CA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, Lake Tahoe, CA AGENCY... annual safety zone for the Fourth of July Fireworks, Lake Tahoe, California, located off Incline Village...,000 foot safety zone for the annual Fourth of July Fireworks Display in 33 CFR 165.1191 on July 4...

Military maneuvers and biodiversity: strange arrangements in southern California.

Treesearch

Sally Duncan

1998-01-01

How can we maintain biodiversity as human population levels continue to increase at a rapid rate? This issue of Science Findings focuses on southern California, one of the richest areas of biodiversity in the country, and home of 1.5 million people. Pacific Northwest Research scientist Ross Kiester, in conjunction with a cooperative research agreement with Harvard...

Southern California as seen from the Apollo 7 spacecraft

NASA Technical Reports Server (NTRS)

1968-01-01

This view of southern California as seen from the Apollo 7 spacecraft during its 18th revolution of the earth. Photographed from an altitude of 124 nautical miles. The coast of California can be seen from Point Mugu southward to Oceanside. Santa Catalina can be seen below the off shore clouds. Details of the Los Angeles area are obscured by pollution which extends from Banning westard for 100 miles to beyond Malibu. In the upper portion of the photograph can be seen (left to right) the San Joaquin Valley beyond Bakersfield, the Techachapi Mountains, the Sierra Nevada, Owens Valley, Death Valley and the Mojave Desert.

Southern California as seen from the Apollo 7 spacecraft

NASA Image and Video Library

1968-10-12

This view of southern California as seen from the Apollo 7 spacecraft during its 18th revolution of the earth. Photographed from an altitude of 124 nautical miles. The coast of California can be seen from Point Mugu southward to Oceanside. Santa Catalina can be seen below the off shore clouds. Details of the Los Angeles area are obscured by pollution which extends from Banning westard for 100 miles to beyond Malibu. In the upper portion of the photograph can be seen (left to right) the San Joaquin Valley beyond Bakersfield, the Techachapi Mountains, the Sierra Nevada, Owens Valley, Death Valley and the Mojave Desert.

Primary particulate matter from ocean-going engines in the Southern California Air Basin.

PubMed

Agrawal, Harshit; Eden, Rudy; Zhang, Xinqiu; Fine, Philip M; Katzenstein, Aaron; Miller, J Wayne; Ospital, Jean; Teffera, Solomon; Cocker, David R

2009-07-15

The impact of primary fine particulate matter (PM2.5) from ship emissions within the Southern California Air Basin is quantified by comparing in-stack vanadium (V) and nickel (Ni) measurements from in-use ocean-going vessels (OGVs) with ambient measurements made at 10 monitoring stations throughout Southern California. V and Ni are demonstrated as robust markers for the combustion of heavy fuel oil in OGVs, and ambient measurements of fine particulate V and Ni within Southern California are shown to decrease inversely with increased distance from the ports of Los Angeles and Long Beach (ports). High levels of V and Ni were observed from in-stack emission measurements conducted on the propulsion engines of two different in-use OGVs. The in-stack V and Ni emission rates (g/h) normalized by the V and Ni contents in the fuel tested correlates with the stack total PM emission rates (g/h). The normalized emission rates are used to estimate the primary PM2.5 contributions from OGVs at 10 monitoring locations within Southern California. Primary PM2.5 contributions from OGVs were found to range from 8.8% of the total PM2.5 at the monitoring location closest to the port (West Long Beach) to 1.4% of the total PM2.5 at the monitoring location 80 km inland (Rubidoux). The calculated OGV contributions to ambient PM2.5 measurements at the 10 monitoring sites agree well with estimates developed using an emission inventory based regional model. Results of this analysis will be useful in determining the impacts of primary particulate emissions from OGVs upon worldwide communities downwind of port operations.

Permanent GPS Geodetic Array in Southern California (PGGA) and GPS observations in Indonesia

NASA Technical Reports Server (NTRS)

Bock, Yehuds

1994-01-01

The Permanent GPS Geodetic Array (PGGA) is a network of permanent monitoring GPS stations in southern California devoted to the continuous measurement of crustal deformation in near real-time. The PGGA plays a unique role in studies of the kinematics of crustal deformation and the earthquake cycle in southern California because it is also providing temporally dense geodetic measurements of crustal motion over periods of minutes to variations in regional crustal strain. As it expands and matures the PGGA will play an increasingly important role in the study of active tectonics of southern California by bridging the frequency range between seismology, observatory geodesy, paleoseismology, and geology. In Indonesia GPS data is used for measurement of a large scale crustal deformation, extending from north China to the Indonesian archipelago. Indonesia offers a tremendous laboratory to study some of the processes that build continents, and mountains are active there. We began GPS observations in August 1989 on mainland Sumatra and the Mentawai Islands to study the phenomena of oblique plate convergence. We have analyzed the Indonesian data in conjunction with data collected on Christmas and Cocos Islands and at Darwin, Australia, and with the triangulation data in Sumatra.

Bathymetry and Acoustic Backscatter: Northern Santa Barbara Channel, Southern California

USGS Publications Warehouse

Dartnell, Pete; Finlayson, David; Conrad, Jamie; Cochrane, Guy; Johnson, Samuel

2010-01-01

In the summer of 2008, as part of the California Seafloor Mapping Program (CSMP) the U.S. Geological Survey, Coastal and Marine Geology mapped a nearshore region of the northern Santa Barbara Channel in Southern California (fig 1). The CSMP is a cooperative partnership between Federal and State agencies, Universities, and Industry to create a comprehensive coastal/marine geologic and habitat basemap series to support the Marine Life Protection Act (MLPA) inititive. The program is supported by the California Ocean Protection Council and the California Coastal Conservancy. The 2008 mapping collected high resolution bathymetry and acoustic backscatter data using a bathymetric side scan system within State waters from about the 10-m isobath out over 3-nautical miles. This Open-File Report provides these data in a number of different formats, as well as a summary of the mapping mission, maps of bathymetry and backscatter, and FGDC metadata.

77 FR 476 - Endangered and Threatened Species; Recovery Plan Southern Oregon/Northern California Coast Coho...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-05

... and Threatened Species; Recovery Plan Southern Oregon/ Northern California Coast Coho Salmon... Oregon/Northern California Coast (SONCC) Coho Salmon (Oncorhynchus kisutch) Evolutionarily Significant... 95521, Attn: Recovery Coordinator/SONCC Coho Salmon Public Draft Recovery Plan Comments. Hand delivered...

Southern California Disasters II

NASA Technical Reports Server (NTRS)

Nicholson, Heather; Todoroff, Amber L.; LeBoeuf, Madeline A.

2015-01-01

The USDA Forest Service (USFS) has multiple programs in place which primarily utilize Landsat imagery to produce burn severity indices for aiding wildfire damage assessment and mitigation. These indices provide widely-used wildfire damage assessment tools to decision makers. When the Hyperspectral Infrared Imager (HyspIRI) is launched in 2022, the sensor's hyperspectral resolution will support new methods for assessing natural disaster impacts on ecosystems, including wildfire damage to forests. This project used simulated HyspIRI data to study three southern California fires: Aspen, French, and King. Burn severity indices were calculated from the data and the results were quantitatively compared to the comparable USFS products currently in use. The final results from this project illustrate how HyspIRI data may be used in the future to enhance assessment of fire-damaged areas and provide additional monitoring tools for decision support to the USFS and other land management agencies.

Dispersal of river sediment in the Southern California Bight

USGS Publications Warehouse

Warrick, J.A.; Farnsworth, K.L.

2009-01-01

The rivers of Southern California deliver episodic pulses of water, sediment, nutrients, and pollutants to the region's coastal waters. Although river-sediment dispersal is observed in positively buoyant (hypopycnal) turbid plumes extending tens of kilometers from river mouths, very little of the river sediment is found in these plumes. Rather, river sediment settles quickly from hypopycnal plumes to the seabed, where transport is controlled by bottom-boundary layer processes, presumably including fluid-mud (hyperpycnal) gravity currents. Here we investigate the geographical patterns of river-sediment dispersal processes by examining suspended-sediment concentrations and loads and the continental shelf morphology offshore river mouths. Throughout Southern California, river sediment is discharged at concentrations adequately high to induce enhanced sediment settling, including negative buoyancy. The rivers draining the Western Transverse Range produce suspended-sediment concentrations that are orders of magnitude greater than those in the urbanized region and Peninsular Range to the south, largely due to differences in sediment yield. The majority of sediment discharge from the Santa Clara River and Calleguas Creek occurs above the theoretical negative buoyancy concentration (>40 g/l). These rivers also produce event sediment loading as great as the Eel River, where fluid-mud gravity currents are observed. The continental shelf of Southern California has variable morphology, which influences the ability to transport via gravity currents. Over half of the rivers examined are adjacent to shelf slopes greater than 0.01, which are adequately steep to sustain auto-suspending gravity currents across the shelf, and have little (<10 m) Holocene sediment accumulation. Shelf settings of the Ventura, Santa Clara, and Tijuana Rivers are very broad and low sloped (less than 0.004), which suggests that fluid-mud gravity currents could transport across these shelves, albeit slowly

Los Angeles-Long Beach area of Southern California as seen from Apollo 9

NASA Image and Video Library

1969-03-09

AS09-22-3436 (March 1969) --- Los Angeles-Long Beach area of southern California, as photographed from the Apollo 9 spacecraft during its 92nd revolution of Earth. Santa Catalina Island is located off the coast. The California coastline is visible from San Clemente northward to Point Dume. Clouds cover most of the San Gabriel Mountains around Los Angeles.

Ecology and control of an introduced population of Southern Watersnakes (Nerodia fasciata) in southern California

USGS Publications Warehouse

Reed, Robert; Todd, Brian D; Miano, Oliver J.; Canfield, Mark; Fisher, Robert N.; McMartin, Louanne

2016-01-01

Native to the southeastern United States, Southern Watersnakes (Nerodia fasciata) are known from two sites in California, but their ecological impacts are poorly understood. We investigated the ecology of Southern Watersnakes in Machado Lake, Harbor City, Los Angeles County, California, including an assessment of control opportunities. We captured 306 watersnakes as a result of aquatic trapping and hand captures. We captured snakes of all sizes (162–1063 mm snout–vent length [SVL], 3.5–873.3 g), demonstrating the existence of a well-established population. The smallest reproductive female was 490 mm SVL and females contained 12–46 postovulatory embryos (mean  =  21). Small watersnakes largely consumed introduced Western Mosquitofish (Gambusia affinis), while larger snakes specialized on larval and metamorph American Bullfrogs (Lithobates catesbeianus) and Green Sunfish (Lepomis cyanellus). Overall capture per unit effort (CPUE) in traps declined with time during an intensive 76-d trapping bout, but CPUE trends varied considerably among traplines and it is unlikely that the overall decline in CPUE represented a major decrease in the snake population size. Although we found no direct evidence that Southern Watersnakes are affecting native species in Machado Lake, this population may serve as a source for intentional or unintentional transportation of watersnakes to bodies of water containing imperiled native prey species or potential competitors.

The evolution of the southern California uplift, 1955 through 1976

USGS Publications Warehouse

Castle, Robert O.; Elliot, Michael R.; Church, Jack P.; Wood, Spencer H.

1984-01-01

time between 1974 and 1976. Accumulating evidence indicates that nearly all the area included with the southern California uplift underwent similar uplift and partial collapse during the early part of the 20th century. Thus we infer that the recent uplift represents but a single event in an ongoing, more or less cyclic deformational process characterized by a period of about 50 years. Even though less than two full cycles are expressed in the geodetic record, the cumulative rate of uplift near the center of the recent uplift probably has averaged about 5 mm/yr, a value that is roughly consistent with the uplift rates that have been deduced for the late Quaternary emergent marine terraces along the south flank of the Transverse Ranges. Although the evolution of the recent uplift is relatively well defined, its correlation with the regional seismicity is poorly defined. A comparison between the occurrence of southern California earthquakes of magnitude ≥4 during the period 1932 to 1976 with the 1974 configuration of the uplift demonstrates the existence of (1) relatively aseismic areas within the western lobe of the uplift (in the western Transverse Ranges), in the central part of the uplift (in the western Mojave Desert), and along an east-trending zone that extends into the eastern Mojave athwart the south flank of the uplift (north of the Salton Sea) and (2) localized concentrations of seismic activity along the flanks of the uplift. Moreover, 9 of the 10 largest earthquakes recorded within or around the area of the southern California uplift during the period 1932 to 1976 (the 1933 Long Beach, the 1941 Santa Barbara, the 1946 Walker Pass, the 1947 Manix, the 1948 Desert Hot Springs, and the four major 1952 Kern County shocks) occurred before the inception of the uplift in 1959 or 1960. The area embraced by the southern California uplift has been identified with geodetically defined horizontal strain, part of which may have accumulated as a major north

Ambient-noise Tomography of the Southern California Lithosphere

NASA Astrophysics Data System (ADS)

Basini, P.; Liu, Q.; Tape, C.

2012-12-01

We exploit the stacked ambient noise cross-correlation functions (NCF) to improve the 3-D velocity structures of southern California crust and upper mantle. NCFs are extracted between pairs of seismic stations as approximations to 3D Greens functions based on the assumption of diffuse wavefields. Thanks to the dense instrumental coverage in south California a high number (around 13000) of NCFs are available that allow us to reach anunprecedented high imaging resolution. The 3-D crustal model m16 of Tape et al. (2009) which describes the detailed crustal variation of southern California region is incorporated into the starting model of our adjoint tomographic inversions. The use of 3D initial model help reduce the nonlinearity of the inverse problem and the number of required iterations. We iteratively improve the velocity model by combining spectral-element (SEM) simulations of seismic wave propagation with Frechet derivatives computed by adjoint methods. The multi-taper traveltime misfit function that quantifies the difference between NCFs (measured over the windows of predominantly surface waves at the period range of 10-20 seconds) and 3D Greens functions for the current model also defines the adjoint sources which produces the necessary Frechet derivatives (sensitivity kernels) through an adjoint simulation. Interesting mantle heterogeneities are revealed due to the improved depth resolution of surface waves. The quality of inversion results may be assessed through the misfit between NCFs and Greens functions for the final model in terms of traveltime, amplitude as well as full waveform. An independent set of earthquakes data and synthetics may also be introduced to verify the final mode.

50 CFR 226.210 - Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California...

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS DESIGNATED CRITICAL HABITAT § 226.210 Central California... (Oncorhynchus kisutch). Critical habitat is designated to include all river reaches accessible to listed coho... part. Critical habitat consists of the water, substrate, and adjacent riparian zone of estuarine and...

50 CFR 226.210 - Central California Coast Coho Salmon (Oncorhynchus kisutch), Southern Oregon/Northern California...

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS DESIGNATED CRITICAL HABITAT § 226.210 Central California... (Oncorhynchus kisutch). Critical habitat is designated to include all river reaches accessible to listed coho... part. Critical habitat consists of the water, substrate, and adjacent riparian zone of estuarine and...

75 FR 46917 - Foreign-Trade Zone 153 - San Diego, California, Site Renumbering Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-04

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board Foreign-Trade Zone 153 - San Diego, California, Site Renumbering Notice Foreign-Trade Zone 153 was approved by the Foreign-Trade Zones Board on October 14, 1988 (Board Order 394, 53 FR 41616, 10/24/88) and expanded on December 16, 1991 (Board Order 548, 56 FR 67057, 12/27/91) and on August 23, 200...

Using Google Earth to Explore Strain Rate Models of Southern California

NASA Astrophysics Data System (ADS)

Richard, G. A.; Bell, E. A.; Holt, W. E.

2007-12-01

A series of strain rate models for the Transverse Ranges of southern California were developed based on Quaternary fault slip data and geodetic data from high precision GPS stations in southern California. Pacific-North America velocity boundary conditions are applied for all models. Topography changes are calculated using the model dilatation rates, which predict crustal thickness changes under the assumption of Airy isostasy and a specified rate of crustal volume loss through erosion. The models were designed to produce graphical and numerical output representing the configuration of the region from 3 million years ago to 3 million years into the future at intervals of 50 thousand years. Using a North American reference frame, graphical output for the topography and faults and numerical output for locations of faults and points on the crust marked by the locations on cities were used to create data in KML format that can be used in Google Earth to represent time intervals of 50 thousand years. As markers familiar to students, the cities provide a geographic context that can be used to quantify crustal movement, using the Google Earth ruler tool. By comparing distances that markers for selected cities have moved in various parts of the region, students discover that the greatest amount of crustal deformation has occurred in the vicinity of the boundary between the North American and Pacific plates. Students can also identify areas of compression or extension by finding pairs of city markers that have converged or diverged, respectively, over time. The Google Earth layers also reveal that faults that are not parallel to the plate boundary have tended to rotate clockwise due to the right lateral motion along the plate boundary zone. KML TimeSpan markup was added to two versions of the model, enabling the layers to be displayed in an automatic sequenced loop for a movie effect. The data is also available as QuickTime (.mov) and Graphics Interchange Format (.gif

Analysis of High Spatial, Temporal, and Directional Resolution Recordings of Biological Sounds in the Southern California Bight

DTIC Science & Technology

2013-09-30

transiting whales in the Southern California Bight, b) the use of passive underwater acoustic techniques for improved habitat assessment in biologically...sensitive areas and improved ecosystem modeling, and c) the application of the physics of excitable media to numerical modeling of biological choruses...was on the potential impact of man-made sounds on the calling behavior of transiting humpback whales in the Southern California Bight. The main

BENTON RANGE ROADLESS AREA, CALIFORNIA.

USGS Publications Warehouse

McKee, Edwin H.; Rains, Richard L.

1984-01-01

On the basis of a mineral survey, two parts of the Benton Range Roadless Area, California are considered to have mineral-resource potential. The central and southern part of the roadless area, near several nonoperating mines, has a probable potential for tungsten and gold-silver mineralization in tactite zones. The central part of the area has a substantiated resource potential for gold and silver in quartz veins. Detailed mapping and geochemical sampling for tungsten, gold, and silver in the central and southern part of the roadless area might indicate targets for shallow drilling exploration.

Preparing a population for an earthquake like Chi-Chi: The Great Southern California ShakeOut

USGS Publications Warehouse

Jones, Lucile M.; ,

2009-01-01

The Great Southern California ShakeOut was a week of special events featuring the largest earthquake drill in United States history. On November 13, 2008, over 5 million southern Californians pretended that a magnitude-7.8 earthquake had occurred and practiced actions that could reduce its impact on their lives. The primary message of the ShakeOut is that what we do now, before a big earthquake, will determine what our lives will be like after. The drill was based on a scenario of the impacts and consequences of such an earthquake on the Southern San Andreas Fault, developed by over 300 experts led by the U.S. Geological Survey in partnership with the California Geological Survey, the Southern California Earthquake Center, Earthquake Engineering Research Institute, lifeline operators, emergency services and many other organizations. The ShakeOut campaign was designed and implemented by earthquake scientists, emergency managers, sociologists, art designers and community participants. The means of communication were developed using results from sociological research on what encouraged people to take action. This was structured around four objectives: 1) consistent messages – people are more inclined to believe something when they hear the same thing from multiple sources; 2) visual reinforcement – people are more inclined to do something they see other people doing; 3) encourage “milling” or discussing contemplated action – people need to discuss an action with others they care about before committing to undertaking it; and 4) focus on concrete actions – people are more likely to prepare for a set of concrete consequences of a particular hazard than for an abstract concept of risk. The goals of the ShakeOut were established in Spring 2008 and were: 1) to register 5 million people to participate in the drill; 2) to change the culture of earthquake preparedness in southern California; and 3) to reduce earthquake losses in southern California. All of these

At-sea distribution and abundance of seabirds off southern California: A 20-year comparison

USGS Publications Warehouse

Mason, J.W.; McChesney, G.J.; McIver, W.R.; Carter, H.R.; Takekawa, John Y.; Golightly, R.T.; Ackerman, Joshua T.; Orthmeyer, D.L.; Perry, W.M.; Yee, J.L.; Pierson, M.O.; McCrary, M.D.

2007-01-01

We conducted aerial at-sea and coastal surveys to examine the distribution and abundance of seabirds off southern California, from Cambria, California, to the Mexican border. From May 1999-January 2002, we flew 102 d, covered >54,640 km of transect lines, and conducted nine complete surveys of southern California in January, May, and September. We identified 54 species comprising 12 families and counted >135,000 individuals. Seabird densities were greater along island and mainland coastlines than at sea and were usually greatest in January surveys. Densities were greatest at sea near the northern Channel Islands in January and north of Point Conception in May, and lowest in the southwestern portion of the Southern California Bight in all survey months. On coastal transects, seabird densities were greatest along central and southern portions of the mainland coastline from Point Arguello to Mexico. We estimated that 981,000 ?? 144,000 (x?? ?? SE) seabirds occurred in the study area in January, 862,000 ?? 95,000 in May, and 762,000 ?? 72,000 in September. California Gulls (Larus californicus), Western Grebes (Aechmophorus occidentalis), and Cassin's Auklets (Ptychoramphus aleuticus) were most abundant in January surveys at sea, whereas Sooty and Short-tailed shearwaters (Puffinus griseus and P. tenuirostris), phalaropes (Phalaropus spp.), and Western Gulls (Larus. occidentalis) were most abundant in May and September surveys. On coastal transects, California Gulls, Western Grebes, Western Gulls, and Surf Scoters (Melanitta perspicillata) were most abundant in January; Western Grebes, Western Gulls, Surf Scoters, and Brown Pelicans (Pelecanus occidentalis) were most abundant in May; and Sooty Shearwaters, Short-tailed Shearwaters, Western Gulls, Western Grebes, Brown Pelicans, and Heermann's Gulls (Larus heermanni) were most abundant in September. Compared to historical seabird densities collected in the same area two decades ago (1975-1978 and 1980-1983), abundance

The Miocene Topanga Group of Southern California - A 100-Year History of Changes in Stratigraphic Nomenclature

USGS Publications Warehouse

Campbell, Russell H.; McCulloh, Thane H.; Vedder, John G.

2007-01-01

A review of selected literature summarizes the origin and chronology of changes in usage of 'Topanga' in the Miocene stratigraphic nomenclature of the Los Angeles Basin and adjacent areas in southern California. The review was done to summarize and reconcile some differences in Miocene stratigraphic nomenclature as applied to geologic map compilations of the Santa Ana (Morton, 2004), San Bernardino (Morton and Miller, 2003), Long Beach (Saucedo and others, 2003) and Los Angeles (Yerkes and Campbell, 2005) 30' x 60' quadrangles, all of which are products of the cooperative (California Geological Survey-U.S. Geological Survey) Southern California Areal Mapping Project (SCAMP). The deposition of the Topanga Group spans about 6 my (from as old as about 18 ma to as young as about 12 ma), and the sequence of included strata records changes in provenance and depositional environments that are contemporaneous with part of a major Miocene tectonic episode in southern California -- the 'basin-inception phase' in the evolution of the Neogene Los Angeles basin (Yerkes and others, 1965). The area of Topanga deposition extends to the southern, eastern, northern, and northwestern sides of the Los Angeles basin, as well as the southern part of the eastern Ventura Basin. Topanga beds are inferred to underlie the thick upper Miocene and Pliocene deposits of the central Los Angeles Basin and the southern part of the eastern Ventura Basin; however, they have been reached by drilling only in marginal areas, where the overlying deposits are relatively thin. Post-Topanga strata were deposited in more-restricted areas of rapid subsidence. Selected papers are summarized as they relate to the Topanga nomenclature, and are presented in chronological order.

Heat flow and thermotectonic problems of the central Ventura Basin, southern California

USGS Publications Warehouse

De Rito, R. F.; Lachenbruch, A.H.; Moses, T.H.; Munroe, R.J.

1989-01-01

The Ventura Basin, southern California, is located near the Big Bend area of the San Andreas fault system, within the Transverse Ranges physiographic province. Negative curvature of the Ventura Avenue temperature profiles may be explained by an increase in thermal conductivity associated with tectonic compaction of the underlying Pliocene clastic sequence. Basinwide, heat flow averages about 48 mW/m2, a value which is low relative to most of southern California. As heat flow does not vary systematically to the maximum measured depth of about 4 km, this anomly is not easily explained in terms of hydrologic effects or recent uplift and erosion. However, a diminution of heat flow is an expectable consequence of the accumulation of cold sediments (up to 12 km) since Eocene time. -from Authors

Rapid finite-fault inversions in Southern California using Cybershake Green's functions

NASA Astrophysics Data System (ADS)

Thio, H. K.; Polet, J.

2017-12-01

We have developed a system for rapid finite fault inversion for intermediate and large Southern California earthquakes using local, regional and teleseismic seismic waveforms as well as geodetic data. For modeling the local seismic data, we use 3D Green's functions from the Cybershake project, which were made available to us courtesy of the Southern California Earthquake Center (SCEC). The use of 3D Green's functions allows us to extend the inversion to higher frequency waveform data and smaller magnitude earthquakes, in addition to achieving improved solutions in general. The ultimate aim of this work is to develop the ability to provide high quality finite fault models within a few hours after any damaging earthquake in Southern California, so that they may be used as input to various post-earthquake assessment tools such as ShakeMap, as well as by the scientific community and other interested parties. Additionally, a systematic determination of finite fault models has value as a resource for scientific studies on detailed earthquake processes, such as rupture dynamics and scaling relations. We are using an established least-squares finite fault inversion method that has been applied extensively both on large as well as smaller regional earthquakes, in conjunction with the 3D Green's functions, where available, as well as 1D Green's functions for areas for which the Cybershake library has not yet been developed. We are carrying out validation and calibration of this system using significant earthquakes that have occurred in the region over the last two decades, spanning a range of locations and magnitudes (5.4 and higher).

A Comparison of Management Strategies in the Oak Woodlands of Spain and California

Treesearch

Lynn Huntsinger; James W. Bartolome; Paul F. Starrs

1991-01-01

The characteristics, uses, and management of oak woodlands and savannas in California and southern Spain are compared. There are many similarities between the Spanish dehesa and the California oak woodland. Both are located in Mediterranean climate zones, and are used predominantly for livestock grazing. However the Spanish dehesa is a more diverse and long-standing...

New insights into North America-Pacific Plate boundary deformation from Lake Tahoe, Salton Sea and southern Baja California

NASA Astrophysics Data System (ADS)

Brothers, Daniel Stephen

three offshore faults are synchronous with Colorado River diversions into the basin. The final study was used coincident wide-angle seismic refraction and multichannel seismic reflection surveys that spanned the width of the of the southern Baja California (BC) Peninsula. The data provide insight into the spatial and temporal evolution of the BC microplate capture by the Pacific Plate. Seismic reflection profiles constrain the upper crustal structure and deformation history along fault zone on the western Baja margin and in the Gulf of California. Stratal divergence in two transtensional basins along the Magdalena Shelf records the onset of extension across the Tosco-Abreojos and Santa Margarita faults. We define an upper bound of 12 Ma on the age of the pre-rift sediments and an age of ˜8 Ma for the onset of extension. Tomographic imaging reveals a very heterogeneous upper crust and a narrow, high velocity zone that extends ˜40 km east of the paleotrench and is interpreted to be remnant oceanic crust.

California State Waters Map Series—Offshore of Santa Cruz, California

USGS Publications Warehouse

Cochrane, Guy R.; Dartnell, Peter; Johnson, Samuel Y.; Erdey, Mercedes D.; Golden, Nadine E.; Greene, H. Gary; Dieter, Bryan E.; Hartwell, Stephen R.; Ritchie, Andrew C.; Finlayson, David P.; Endris, Charles A.; Watt, Janet T.; Davenport, Clifton W.; Sliter, Ray W.; Maier, Katherine L.; Krigsman, Lisa M.; Cochrane, Guy R.; Cochran, Susan A.

2016-03-24

upper Quaternary shelf, estuarine, and fluvial sediments deposited as sea level fluctuated in the late Pleistocene. The inner shelf is characterized by bedrock outcrops that have local thin sediment cover, the result of regional uplift, high wave energy, and limited sediment supply. The midshelf occupies part of an extensive, shore-parallel mud belt. The thickest sediment deposits, inferred to consist mainly of lowstand nearshore deposits, are found in the southeastern and northwestern parts of the map area.Coastal sediment transport in the map area is characterized by northwest-to-southeast littoral transport of sediment that is derived mainly from ephemeral streams in the Santa Cruz Mountains and also from local coastal-bluff erosion. During the last approximately 300 years, as much as 18 million cubic yards (14 million cubic meters) of sand-sized sediment has been eroded from the area between Año Nuevo Island and Point Año Nuevo and transported south; this mass of eroded sand is now enriching beaches in the map area. Sediment transport is within the Santa Cruz littoral cell, which terminates in the submarine Monterey Canyon.Benthic species observed in the Offshore of Santa Cruz map area are natives of the cold-temperate biogeographic zone that is called either the “Oregonian province” or the “northern California ecoregion.” This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, the eastern limb of the North Pacific subtropical gyre that flows from southern British Columbia to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 300 km south of the map area), although its associated

Investigating the Evolution of Southern California Salt Marshes: A Facies Model to Understand the Influence of Seismic Events on Environmental Resiliency and Sustainability

NASA Astrophysics Data System (ADS)

Aranda, A. N.; Carlin, J. A.; Rhodes, B. P.; Kirby, M.

2016-02-01

Only 10-20% of the US Pacific coast is estimated to be suitable for marsh development. In southern California specifically, marshes are disappearing ecosystems due to high population and urbanization. The future environmental impacts from climate change on these ecosystems are complicated not only by anthropogenic influences, but also by seismic activity in the region. In general, marsh evolution and response to seismic activity has yet to be fully explored in southern California. This study aims to develop a sediment facies model for salt marsh evolution in southern California by utilizing the salt marshes of the Seal Beach Wetlands (SBW). The SBW is an ideal location to develop the facies model because it straddles the active Newport-Inglewood Fault Zone. We collected sediment cores from the SBW that underwent a variety of sedimentological and geochemical analyses including grain size, X-Ray Fluorescence core scanning, magnetic susceptibility, and loss-on-ignition.. The results show a facies model consisting of sequences of marsh accretion punctuated by seismic events. These seismic events caused the marsh to subside, effectively re-setting marsh development from peat generation at a vegetated marsh state, to subtidal to intertidal mud deposition. The model also allowed us to qualify and quantify marsh recovery as inferred from event intensity, where what we perceived as more intense events resulted in more significant ecosystem disturbances and longer recovery times. Understanding this interplay between seismic activity and marsh development highlights the fragile nature of these ecosystems to climate change and sea level rise, as these stresses will only become amplified by seismic events.

Epipelagic and mesopelagic fishes in the southern California Current System: Ecological interactions and oceanographic influences on their abundance

NASA Astrophysics Data System (ADS)

Koslow, J. Anthony; Davison, Peter; Lara-Lopez, Ana; Ohman, Mark D.

2014-10-01

California Current System, which influences the abundance of many dominant taxa off southern California that have broad biogeographic distributions linked to water masses that extend to the north (Transition Zone/sub-Arctic faunas) or the south (tropical/subtropical faunas).

NASA's AVIRIS Instrument Sheds New Light on Southern California Wildfires

NASA Image and Video Library

2017-12-08

NASA's Airborne Visible Infrared Imaging Spectrometer instrument (AVIRIS), flying aboard a NASA Armstrong Flight Research Center high-altitude ER-2 aircraft, flew over the wildfires burning in Southern California on Dec. 5, 2017 and acquired this false-color image. Active fires are visible in red, ground surfaces are in green and smoke is in blue. AVIRIS is an imaging spectrometer that observes light in visible and infrared wavelengths, measuring the full spectrum of radiated energy. Unlike regular cameras with three colors, AVIRIS has 224 spectral channels from the visible through the shortwave infrared. This permits mapping of fire temperatures, fractional coverage, and surface properties, including how much fuel is available for a fire. Spectroscopy is also valuable for characterizing forest drought conditions and health to assess fire risk. AVIRIS has been observing fire-prone areas in Southern California for many years, forming a growing time series of before/after data cubes. These data are helping improve scientific understanding of fire risk and how ecosystems respond to drought and fire. https://photojournal.jpl.nasa.gov/catalog/PIA11243

Interaction of fire and community development in chaparral of southern California

Treesearch

Philip J. Riggan; Suzanne Goode; Paula M. Jacks; Robert N. Lockwood

1988-01-01

Fire is an ecosystem property rather than an exogenous force in southern California chaparral, and it interacts with processes of drought-mediated canopy development, production, and mortality to affect stability of community composition. Where species that must reproduce from seed, such as Ceanothus crassifolius or Ceanothus...

Air pollution impacts in the mixed conifer forests of southern California

Treesearch

Patrick J. Temple; Andrzej Bytnerowicz; Mark E. Fenn; Mark A. Poth

2005-01-01

Air pollution, principally in the form of photochemical ozone and deposition of nitrogen compounds, has significantly affected mixed conifer forests in the mountains of southern California. Foliar injury, premature needle abscission, crown thinning, and reduced growth and vigor have been well documented, particularly for ponderosa (Pinus ponderosa...

A Grammar of Southern Pomo: An Indigenous Language of California

ERIC Educational Resources Information Center

Walker, Neil Alexander

2013-01-01

Southern Pomo is a moribund indigenous language, one of seven closely related Pomoan languages once spoken in Northern California in the vicinity of the Russian River drainage, Clear Lake, and the adjacent Pacific coast. This work is the first full-length grammar of the language. It is divided into three parts. Part I introduces the sociocultural…

How to sow mustard in burned watersheds of southern California

Treesearch

Clark H. Gleason

1944-01-01

After the chaparral cover of the mountain watersheds in southern California is burned, damage is usually done during winter storms by increased runoff and erosion debris from the denuded area. The damage is done not only to the works of man, but to the watershed itself. Improvements that most often suffer tangible damage include water storage and diversion structures;...

Stress- and Structure-Induced Anisotropy in Southern California From Two Decades of Shear Wave Splitting Measurements

NASA Astrophysics Data System (ADS)

Li, Zefeng; Peng, Zhigang

2017-10-01

We measure shear wave splitting (SWS) parameters (i.e., fast direction and delay time) using 330,000 local earthquakes recorded by more than 400 stations of the Southern California Seismic Network (1995-2014). The resulting 232,000 SWS measurements (90,000 high-quality ones) provide a uniform and comprehensive database of local SWS measurements in Southern California. The fast directions at many stations are consistent with regional maximum compressional stress σHmax. However, several regions show clear deviations from the σHmax directions. These include linear sections along the San Andreas Fault and the Santa Ynez Fault, geological blocks NW to the Los Angeles Basin, regions around the San Jacinto Fault, the Peninsular Ranges near San Diego, and the Coso volcanic field. These complex patterns show that regional stresses and active faults cannot adequately explain the upper crustal anisotropy in Southern California. Other types of local structures, such as local rock types or tectonic features, also play significant roles.

Southern California Association of Governments : public opinion research : Regional Comprehensive Plan (RCP)

DOT National Transportation Integrated Search

1994-05-01

The Southern California Association of Governments (SCAG) commissioned the public opinion research firm of Fairbank, Maslin, Maulin and Associates to conduct focus groups and a public opinion survey on issues related to and addressed by the 1994 Draf...

Magmatism and Epithermal Gold-Silver Deposits of the Southern Ancestral Cascade Arc, Western Nevada and Eastern California

USGS Publications Warehouse

John, David A.; du Bray, Edward A.; Henry, Christopher D.; Vikre, Peter

2015-01-01

Many epithermal gold-silver deposits are temporally and spatially associated with late Oligocene to Pliocene magmatism of the southern ancestral Cascade arc in western Nevada and eastern California. These deposits, which include both quartz-adularia (low- and intermediate-sulfidation; Comstock Lode, Tonopah, Bodie) and quartz-alunite (high-sulfidation; Goldfield, Paradise Peak) types, were major producers of gold and silver. Ancestral Cascade arc magmatism preceded that of the modern High Cascades arc and reflects subduction of the Farallon plate beneath North America. Ancestral arc magmatism began about 45 Ma, continued until about 3 Ma, and extended from near the Canada-United States border in Washington southward to about 250 km southeast of Reno, Nevada. The ancestral arc was split into northern and southern segments across an inferred tear in the subducting slab between Mount Shasta and Lassen Peak in northern California. The southern segment extends between 42°N in northern California and 37°N in western Nevada and was active from about 30 to 3 Ma. It is bounded on the east by the northeast edge of the Walker Lane. Ancestral arc volcanism represents an abrupt change in composition and style of magmatism relative to that in central Nevada. Large volume, caldera-forming, silicic ignimbrites associated with the 37 to 19 Ma ignimbrite flareup are dominant in central Nevada, whereas volcanic centers of the ancestral arc in western Nevada consist of andesitic stratovolcanoes and dacitic to rhyolitic lava domes that mostly formed between 25 and 4 Ma. Both ancestral arc and ignimbrite flareup magmatism resulted from rollback of the shallowly dipping slab that began about 45 Ma in northeast Nevada and migrated south-southwest with time. Most southern segment ancestral arc rocks have oxidized, high potassium, calc-alkaline compositions with silica contents ranging continuously from about 55 to 77 wt%. Most lavas are porphyritic and contain coarse plagioclase �

Sources of sediment to the coastal waters of the Southern California Bight

USGS Publications Warehouse

Warrick, J.A.; Farnsworth, K.L.

2009-01-01

The sources of sediment to the Southern California Bight were investigated with new calculations and published records of sediment fluxes, both natural and anthropogenic. We find that rivers are by far the largest source of sediment, producing over 10 ?? 106 t/yr on average, or over 80% of the sediment input to the Bight. This river flux is variable, however, over both space and time. The rivers draining the Transverse Ranges produce sediment at rates approximately an order of magnitude greater than the Peninsular Ranges (600-1500 t/km2/yr versus <90 t/km2/yr, respectively). Although the Transverse Range rivers represent only 23% of the total Southern California watershed drainage area, they are responsible for over 75% of the total sediment flux. River sediment flux is ephemeral and highly pulsed due to the semiarid climate and the influence of infrequent large storms. For more than 90% of the time, negligible amounts of sediment are discharged from the region's rivers, and over half of the post-1900 sediment load has been discharged during events with recurrence intervals greater than 10 yr. These rare, yet important, events are related to the El Ni??o-Southern Oscillation (ENSO), and the majority of sediment flux occurs during ENSO periods. Temporal trends in sediment discharge due to land-use changes and river damming are also observed. We estimate that there has been a 45% reduction in suspended-sediment flux due to the construction of dams. However, pre-dam sediment loads were likely artificially high due to the massive land-use changes of coastal California to rangeland during the nineteenth century. This increase in sediment production is observed in estuarine deposits throughout coastal California, which reveal that sedimentation rates were two to ten times higher during the nineteenth and twentieth centuries than during pre-European colonization. ?? 2009 The Geological Society of America.

Logs and Scarp Data from a Paloseismic Investigation of the Surprise Valley Fault Zone, Modoc County, California

USGS Publications Warehouse

Personius, Stephen F.; Crone, Anthony J.; Machette, Michael N.; Lidke, David J.; Bradley, Lee-Ann; Mahan, Shannon

2007-01-01

This report contains field and laboratory data from a paleoseismic study of the Surprise Valley fault zone near Cedarville, California. The 85-km-long Surprise Valley fault zone forms the western active margin of the Basin and Range province in northeastern California. The down-to-the-east normal fault is marked by Holocene fault scarps along most of its length, from Fort Bidwell on the north to near the southern end of Surprise Valley. We studied the central section of the fault to determine ages of paleoearthquakes and to better constrain late Quaternary slip rates, which we hope to compare to deformation rates derived from a recently established geodetic network in the region (Hammond and Thatcher, 2005; 2007). We excavated a trench in June 2005 across a prominent fault scarp on pluvial Lake Surprise deltaic sediments near the mouth of Cooks Canyon, 4 km north of Cedarville. This site was chosen because of the presence of a well-preserved fault scarp and its development on lacustrine deposits thought to be suitable for luminescence dating. We also logged a natural exposure of the fault in similar deltaic sediments near the mouth of Steamboat Canyon, 11 km south of Cedarville, to better understand the along-strike extent of surface ruptures. The purpose of this report is to present photomosaics, trench, drill hole, and stream exposure logs; scarp profiles; and fault slip, tephrochronologic, radiocarbon, luminescence, and unit description data obtained during this investigation. We do not attempt to use the data presented herein to construct a paleoseismic history of this part of the Surprise Valley fault zone; that history will be the subject of a future report.

Coastal ocean transport patterns in the central Southern California Bight

USGS Publications Warehouse

Noble, M.A.; Rosenberger, K.J.; Hamilton, P.; Xu, J. P.

2009-01-01

In the past decade, several large programs that monitor currents and transport patterns for periods from a few months to a few years were conducted by a consortium of university, federal, state, and municipal agencies in the central Southern California Bight, a heavily urbanized section of the coastal ocean off the west coast of the United States encompassing Santa Monica Bay, San Pedro Bay, and the Palos Verdes shelf. These programs were designed in part to determine how alongshelf and cross-shelf currents move sediments, pollutants, and suspended material through the region. Analysis of the data sets showed that the current patterns in this portion of the Bight have distinct changes in frequency and amplitude with location, in part because the topography of the shelf and upper slope varies rapidly over small spatial scales. However, because the mean, subtidal, and tidal-current patterns in any particular location were reasonably stable with time, one could determine a regional pattern for these current fields in the central Southern California Bight even though measurements at the various locations were obtained at different times. In particular, because the mean near-surface flows over the San Pedro and Palos Verdes shelves are divergent, near-surface waters from the upper slope tend to carry suspended material onto the shelf in the northwestern portion of San Pedro Bay. Water and suspended material are also carried off the shelf by the mean and subtidal flow fields in places where the orientation of the shelf break changes abruptly. The barotropic tidal currents in the central Southern California Bight flow primarily alongshore, but they have pronounced amplitude variations over relatively small changes in alongshelf location that are not totally predicted by numerical tidal models. Nonlinear internal tides and internal bores at tidal frequencies are oriented more across the shelf. They do not have a uniform transport direction, since they move fine sediment

Water movement through a thick unsaturated zone underlying an intermittent stream in the western Mojave Desert, southern California, USA

USGS Publications Warehouse

Izbicki, J.A.; Radyk, J.; Michel, R.L.

2000-01-01

Previous studies indicated that small amounts of recharge occur as infiltration of intermittent streamflow in washes in the upper Mojave River basin, in the western Mojave Desert, near Victorville, California. These washes flow only a few days each year after large storms. To reach the water table, water must pass through an unsaturated zone that is more than 130 m thick. Results of this study, done in 1994-1998, showy that infiltration to depths below the root zone did not occur at control sites away from the wash. At these sites, volumetric water contents were as low as 0.01 and water potentials (measured as the combination of solute and matric potentials using a water activity meter) were as negative as -14,000 kPa. Water-vapor movement was controlled by highly negative solute potentials associated with the accumulation of soluble salts in the unsaturated zone. Highly negative matric potentials above and below the zone of maximum solute accumulation result from movement of water vapor toward the highly negative solute potentials at that depth. The ??18O and ??D (delta oxygen-18 and delta deuterium) isotopic composition of water in coarse-grained deposits plots along a Rayleigh distillation line consistent with removal of water in coarse-grained layers by vapor transport. Beneath Oro Grande Wash, water moved to depths below the root zone and, presumably, to the water table about 130 m below land surface. Underneath Oro Grande Wash, volumetric water contents were as high as 0.27 and water potentials (measured as matric potential using tensiometers) were between -1.8 and -50 kPa. On the basis of tritium data, water requires at least 180-260 years to infiltrate to the water table. Clay layers impede the downward movement of water. Seasonal changes in water vapor composition underneath the wash are consistent with the rapid infiltration of a small quantity of water to great depths and subsequent equilibration of vapor with water in the surrounding material. It may be

Hydrogen peroxide measurements in recreational marine bathing waters in Southern California, USA.

PubMed

Clark, Catherine D; De Bruyn, Warren J; Hirsch, Charlotte M; Jakubowski, Scott D

2010-04-01

Hydrogen peroxide (H(2)O(2)) was measured in the surf zone at 13 bathing beaches in Southern California, USA. Summer dry season concentrations averaged 122 +/- 38 nM with beaches with tide pools having lower levels (50-90 nM). No significant differences were observed for ebb waters at a salt marsh outlet vs. a beach (179 +/- 20 vs. 163 +/- 26 nM), and between ebb and flood tides at one site (171 +/- 24 vs. 146 +/- 42 nM). H(2)O(2) levels showed little annual variation. Diel cycling was followed over short (30 min; 24 h study) and long (d) time scales, with maximum afternoon concentration = 370 nM and estimated photochemical production rate of 44 nM h(-1). There was no correlation between the absorbance coefficient at 300 nm (used as a measure of chromophoric dissolved organic matter (CDOM) levels) and H(2)O(2). H(2)O(2) concentrations measured in this study are likely sufficient to inhibit fecal indicator bacteria in marine recreational waters through indirect photoinactivation. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Microcystin Prevalence throughout Lentic Waterbodies in Coastal Southern California

PubMed Central

Nagoda, Carey; Kudela, Raphael M.; Tatters, Avery; Caron, David A.; Busse, Lilian; Brown, Jeff; Sutula, Martha

2017-01-01

Toxin producing cyanobacterial blooms have increased globally in recent decades in both frequency and intensity. Despite the recognition of this growing risk, the extent and magnitude of cyanobacterial blooms and cyanotoxin prevalence is poorly characterized in the heavily populated region of southern California. Recent assessments of lentic waterbodies (depressional wetlands, lakes, reservoirs and coastal lagoons) determined the prevalence of microcystins and, in some cases, additional cyanotoxins. Microcystins were present in all waterbody types surveyed although toxin concentrations were generally low across most habitats, as only a small number of sites exceeded California’s recreational health thresholds for acute toxicity. Results from passive samplers (Solid Phase Adsorption Toxin Tracking (SPATT)) indicated microcystins were prevalent throughout lentic waterbodies and that traditional discrete samples underestimated the presence of microcystins. Multiple cyanotoxins were detected simultaneously in some systems, indicating multiple stressors, the risk of which is uncertain since health thresholds are based on exposures to single toxins. Anatoxin-a was detected for the first time from lakes in southern California. The persistence of detectable microcystins across years and seasons indicates a low-level, chronic risk through both direct and indirect exposure. The influence of toxic cyanobacterial blooms is a more complex stressor than presently recognized and should be included in water quality monitoring programs. PMID:28737685

Analysis of California Condor (Gymnogyps californianus) use of six management units using location data from global positioning system transmitters, southern California, 2004-09-Initial report

USGS Publications Warehouse

Johnson, Matthew; Kern, Jeffrey; Haig, Susan M.

2010-01-01

This report provides an analysis of California Condor (Gymnogyps californianus) space use of six management units in southern California (Hopper Mountain and Bitter Creek National Wildlife Refuges, Wildlands Conservancy-Wind Wolves Preserve, Tejon Mountain Village Specific Plan, California Condor Study Area, and the Tejon Ranch excluding Tejon Mountain Village Specific Plan and California Condor Study Area). Space use was analyzed to address urgent management needs using location data from Global Positioning System transmitters. The U.S. Fish and Wildlife Service provided the U.S. Geological Survey with location data (2004-09) for California Condors from Global Positioning System transmitters and Geographic Information System data for the six management units in southern California. We calculated relative concentration of use estimates for each management unit for each California Condor (n = 21) on an annual basis (n = 39 annual home ranges) and evaluated resource selection for the population each year using the individual as our sampling unit. The most striking result from our analysis was the recolonization of the Tejon Mountain Village Specific Plan, California Condor Study Area, and Tejon Ranch management units during 2008. During 2004-07, the home range estimate for two (25 percent) California Condors overlapped the Tejon Mountain Village Specific Plan, California Condor Study Area, and Tejon Ranch management units (n = 8), and use within the annual home range generally was bimodal and was concentrated on the Bitter Creek and Hopper Mountain National Wildlife Refuges. However, 10 (77 percent) California Condor home ranges overlapped the Tejon Mountain Village Specific Plan, California Condor Study Area, and Tejon Ranch management units during 2008 (n = 13), and by 2009, the home range of every condor carrying a Global Positioning System transmitter (n = 14) overlapped these management units. Space use was multimodal within the home range during 2008-09 and was

The precarious persistence of the endangered Sierra Madre yellow-legged frog Rana muscosa in southern California, USA

USGS Publications Warehouse

Backlin, Adam R.; Hitchcock, Cynthia J.; Gallegos, Elizabeth A.; Yee, Julie L.; Fisher, Robert N.

2015-01-01

We conducted surveys for the Endangered Sierra Madre yellow-legged frog Rana muscosa throughout southern California to evaluate the current distribution and status of the species. Surveys were conducted during 2000–2009 at 150 unique streams and lakes within the San Gabriel, San Bernardino, San Jacinto, and Palomar mountains of southern California. Only nine small, geographically isolated populations were detected across the four mountain ranges, and all tested positive for the amphibian chytrid fungus Batrachochytrium dendrobatidis. Our data show that when R. muscosa is known to be present it is easily detectable (89%) in a single visit during the frog's active season. We estimate that only 166 adult frogs remained in the wild in 2009. Our research indicates that R. muscosa populations in southern California are threatened by natural and stochastic events and may become extirpated in the near future unless there is some intervention to save them.

Intra-community implications of implementing multiple tsunami-evacuation zones in Alameda, California

USGS Publications Warehouse

Peters, Jeff; Wood, Nathan J.; Wilson, Rick; Miller, Kevin

2016-01-01

Tsunami-evacuation planning in coastal communities is typically based on maximum evacuation zones for a single scenario or a composite of sources; however, this approach may over-evacuate a community and overly disrupt the local economy and strain emergency-service resources. To minimize the potential for future over-evacuations, multiple evacuation zones based on arrival time and inundation extent are being developed for California coastal communities. We use the coastal city of Alameda, California (USA), as a case study to explore population and evacuation implications associated with multiple tsunami-evacuation zones. We use geospatial analyses to estimate the number and type of people in each tsunami-evacuation zone and anisotropic pedestrian evacuation models to estimate pedestrian travel time out of each zone. Results demonstrate that there are tens of thousands of individuals in tsunami-evacuation zones on the two main islands of Alameda, but they will likely have sufficient time to evacuate before wave arrival. Quality of life could be impacted by the high number of government offices, schools, day-care centers, and medical offices in certain evacuation zones and by potentially high population density at one identified safe area after an evacuation. Multi-jurisdictional evacuation planning may be warranted, given that many at-risk individuals may need to evacuate to neighboring jurisdictions. The use of maximum evacuation zones for local tsunami sources may be warranted given the limited amount of available time to confidently recommend smaller zones which would result in fewer evacuees; however, this approach may also result in over-evacuation and the incorrect perception that successful evacuations are unlikely.

Multivariate Statistical Models for Predicting Sediment Yields from Southern California Watersheds

USGS Publications Warehouse

Gartner, Joseph E.; Cannon, Susan H.; Helsel, Dennis R.; Bandurraga, Mark

2009-01-01

Debris-retention basins in Southern California are frequently used to protect communities and infrastructure from the hazards of flooding and debris flow. Empirical models that predict sediment yields are used to determine the size of the basins. Such models have been developed using analyses of records of the amount of material removed from debris retention basins, associated rainfall amounts, measures of watershed characteristics, and wildfire extent and history. In this study we used multiple linear regression methods to develop two updated empirical models to predict sediment yields for watersheds located in Southern California. The models are based on both new and existing measures of volume of sediment removed from debris retention basins, measures of watershed morphology, and characterization of burn severity distributions for watersheds located in Ventura, Los Angeles, and San Bernardino Counties. The first model presented reflects conditions in watersheds located throughout the Transverse Ranges of Southern California and is based on volumes of sediment measured following single storm events with known rainfall conditions. The second model presented is specific to conditions in Ventura County watersheds and was developed using volumes of sediment measured following multiple storm events. To relate sediment volumes to triggering storm rainfall, a rainfall threshold was developed to identify storms likely to have caused sediment deposition. A measured volume of sediment deposited by numerous storms was parsed among the threshold-exceeding storms based on relative storm rainfall totals. The predictive strength of the two models developed here, and of previously-published models, was evaluated using a test dataset consisting of 65 volumes of sediment yields measured in Southern California. The evaluation indicated that the model developed using information from single storm events in the Transverse Ranges best predicted sediment yields for watersheds in San

Nitrogen deposition effects on coastal sage vegetation of southern California

Treesearch

Edith B. Allen; Pamela E. Padgett; Andrzej Bytnerowicz; Richard Minnich

1998-01-01

The coastal sage scrub (CSS) vegetation of southern California has been declining in land area and in shrub density over the past 60 years or more, and is being replaced by Mediterranean annual grasses in many areas. Although much of this loss is attributable to agriculture, grazing, urbanization and frequent fire, even protected areas have experienced a loss in native...

Deterioration of fire-killed timber in southern Oregon and northern California.

Treesearch

Eini C. Lowell; James M. Cahill

1996-01-01

Deterioration of fire-killed timber in the coastal mountains of southern Oregon and northern California was monitored over a 3 yr period (1988-1990). Defect was identified and measured on felled and bucked sample trees by using Scribner and cubic scaling rules. Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis),...

Globalization and Higher Education in Southern California: Views from the Professoriate

ERIC Educational Resources Information Center

Weldon, Peter A.; Rexhepi, Jevdet; Chang, ChenWei; Jones, Lauren; Layton, Lucas Arribas; Liu, Amy; McKibben, Susan; Misiaszek, Greg; Olmos, Liliana; Quon, Amy; Torres, Carlos Alberto

2011-01-01

In this study, faculty at institutions of higher education in Southern California were surveyed to determine the ways they interpret the effects of globalization dynamics upon their various teaching and research activities. Faculty in the state's three higher education tiers spoke positively about the intellectual benefits to be gained by exposure…

Chilblains in Southern California: two case reports and a review of the literature.

PubMed

Gordon, Rebecca; Arikian, Anne M; Pakula, Anita S

2014-11-22

Chilblains or perniosis is an acrally located cutaneous eruption that occurs with exposure to cold. Chilblains can be classified into primary and secondary forms. The primary or idiopathic form is not associated with an underlying disease and is clinically indistinguishable from the secondary form. The secondary form is associated with an underlying condition such as connective tissue disease, monoclonal gammopathy, cryoglobulinemia, or chronic myelomonocytic leukemia. Histopathology cannot accurately help distinguish the primary from secondary forms of chilblains. This article will raise the awareness of chilblains by presenting two unusual case reports of chilblains in men from Southern California with discussion of the appropriate evaluation and treatment of this condition. Case 1: A 56-year-old Caucasian man presented in January to a Southern California primary care clinic with a report of tingling and burning in both feet, followed by bluish discoloration and swelling as well as blistering. He had no unusual cold exposure prior to the onset of his symptoms. He had a history of "white attacks" in his hands consistent with Raynaud's phenomenon. His symptoms gradually resolved over a 3-week period. Case 2: A 53-year-old Caucasian man also presented to a Southern California clinic in January with a 3-week history of painful tingling in his toes, and subsequent purplish-black discoloration of the toes in both feet. His symptoms occurred 1 week after a skiing trip. He had partial improvement with warming measures. His symptoms resolved 2 weeks after his initial presentation. Chilblains is a relatively uncommon entity in warmer climates but can present during the winter months. Primary care providers in warmer climates such as Southern California in the USA may be unfamiliar with its presentation. It can be diagnosed clinically by the appearance of typical lesions during the cold damp season. Through a thorough history, physical examination and selected laboratory

Regional bankfull geometry relationships for southern California mountain streams and hydrologic applications

NASA Astrophysics Data System (ADS)

Modrick, Theresa M.; Georgakakos, Konstantine P.

2014-09-01

This study develops and intercompares regional relationships for bankfull channel width, hydraulic depth, and cross-sectional area for southern California mountain streams based on several data sources: surveyed streams, US Geological Survey stream survey reports, and existing literature. Although considerable uncertainty exists in estimating bankfull conditions, the relationships developed from the varying data sources show significant agreement. For small watersheds with drainage area ranging from 15 to ~ 2000 km2, the estimates of bankfull top width ranged from 7.2 to 44.5 m and hydraulic depth estimates ranged from 0.35 to 1.15 m. The utility of the developed bankfull geometry regional curves is demonstrated for southern California catchments through (a) the computation of the bankfull discharge and (b) the estimation of the surface runoff response necessary to produce bankfull conditions in the streams at the outlet of these catchments. For selected locations with instantaneous flow records, the occurrence frequency of events exceeding bankfull flow was examined for the available 10-15 year span of observational records. Bankfull discharge estimates for all small watersheds in the region ranged from 1.3 to 74 m3/s, while the range at the selected gauged stream locations was from 2.6 to 16.4 m3/s. Stream locations along the Transverse Mountains of southern California showed an average occurrence frequency of less than 1 year, whereas along the Peninsular Mountains the average return period tended to be greater than 1 year. The application of the regional curves to the estimation of the surface runoff response necessary to produce bankfull conditions at the channel outlets of small catchments may be used as an index for conditions of minor flooding with saturated soils. This surface runoff response index ranges from 2.0 to 5.5 mm for a 3-hour rainfall duration for southern California watersheds greater than 15 km2 in area. Differences between the values for the

Southern California Drosophila Conference: Irvine, CA - September 11, 2009.

PubMed

Rattner, Barbara P

2009-01-01

As has become tradition, this year's Southern California Drosophila Conference was hosted by the Developmental Biology Center (http://dbc.bio.uci.edu/) at the University of California, Irvine. On September 11, 2009, speakers from institutions in Los Angeles, Orange, Riverside, and San Diego Counties presented their latest results in an informal and friendly atmosphere and had the opportunity to learn about new resources and facilities, establish collaborations, and network about job openings and training opportunities. The talks presented covered the use of flies to study a variety of topics including the mechanisms of action of human pathogens, human diseases, and aging and lifespan extension. In addition, attendees heard about aspects of Drosophila neuronal development, olfactory behavior, transcriptional regulation, and signal transduction. Some of the highlights of the meeting are summarized in this brief report.

Recruitment and Retention of Information Technology Professionals in Southern California Municipal Government

ERIC Educational Resources Information Center

Roberts, Douglas P.

2009-01-01

This study investigates the recruitment and retention challenges, facing municipal government IT organizations in Southern California, by examining the relationships between worker demographics, competencies, experience levels, tenure, and training within the organizations. Utilizing a mixed method, non-experimental design, the study examines…

Atmospheric nitrogen deposition and habitat alteration in terrestrial and aquatic ecosystems in southern California: implications for threatened and endangered species

Treesearch

Mark Fenn; Mark Poth; Thomas Meixner

2005-01-01

Recent studies in the transverse ranges (including Class I Wilderness areas) of southern California have emphasized the strong linkage between levels of air pollution-related atmospheric nitrogen (N) inputs into montane watersheds and levels of nitrate in surface and subsurface drainage waters (fig. 1). Nitrate concentrations in streamwater in southern California are...

Meteorological Controls on Biomass Burning During Santa Ana Events in Southern California

NASA Technical Reports Server (NTRS)

Veraverbeke, Sander; Capps, Scott; Hook, Simon J.; Randerson, James T.; Jin, Yufang; Hall, Alex

2013-01-01

Fires occurring during Santa Ana (SA) events in southern California are driven by extreme fire weather characterized by high temperatures, low humidities, and high wind speeds. We studied the controls on burned area and carbon emissions during two intensive SA burning periods in 2003 and 2007. We therefore used remote sensing data in parallel with fire weather simulations of the Weather and Regional Forecast model. Total carbon emissions were approximately 1800 gigagrams in 2003 and 900 gigagrams in 2007, based on a daily burned area and a fire emission model that accounted for spatial variability in fuel loads and combustion completeness. On a regional scale, relatively strong positive correlations were found between the daily Fosberg fire weather index and burned area/emissions (probability is less than 0.01). Our analysis provides a quantitative assessment of relationships between fire activity and weather during severe SA fires in southern California.

Southern California Mountains and Foothills Assessment: Habitat and Species Conservation Issues

Treesearch

John R. Stephenson; Gena M. Calcarone

1999-01-01

The Southern California Mountains and Foothills Assessment: Habitat and Species Conservation Issues provides detailed information about current conditions and trends for ecological systems and species in the region. This information can be used by land managers to develop broad land management goals and priorities and provides the context for decisions specific to...

Seismic Structural Setting of Western Farallon Basin, Southern Gulf of California, Mexico.

NASA Astrophysics Data System (ADS)

Pinero-Lajas, D.; Gonzalez-Fernandez, A.; Lopez-Martinez, M.; Lonsdale, P.

2007-05-01

Data from a number of high resolution 2D multichannel seismic (MCS) lines were used to investigate the structure and stratigraphy of the western Farallon basin in the southern Gulf of California. A Generator-Injector air gun provided a clean seismic source shooting each 12 s at a velocity of 6 kts. Each signal was recorded during 6- 8 s, at a sampling interval of 1 ms, by a 600 m long digital streamer with 48 channels and a spacing of 12.5 m. The MCS system was installed aboard CICESE's (Centro de Investigacion Cientifica y de Educacion Superior de Ensenada) 28 m research vessel Francisco de Ulloa. MCS data were conventionally processed, to obtain post- stack time-migrated seismic sections. The MCS seismic sections show a very detailed image of the sub-bottom structure up to 2-3 s two-way travel time (aprox. 2 km). We present detailed images of faulting based on the high resolution and quality of these data. Our results show distributed faulting with many active and inactive faults. Our study also constrains the depth to basement near the southern Baja California eastern coast. The acoustic basement appears as a continuous feature in the western part of the study area and can be correlated with some granite outcrops located in the southern Gulf of California islands. To the East, near the center of the Farallon basin, the acoustic basement changes, it is more discontinuous, and the seismic sections show a number of diffracted waves.

A kinematic model for the late Cenozoic development of southern California crust and upper mantle

NASA Technical Reports Server (NTRS)

Humphreys, Eugene D.; Hager, Bradford H.

1990-01-01

A model is developed for the young and ongoing kinematic deformation of the southern California crust and upper mantle. The kinematic model qualitatively explains both the overall seismic structure of the upper mantle and much of the known geological history of the late Cenozoic as consequences of ongoing convection beneath southern California. In this model, the high-velocity upper-mantle anomaly of the Transverse ranges is created through the convergence and sinking of the entire thickness of subcrustal lihtosphere, and the low-velocity upper-mantle anomaly beneath the Salton Trough region is attributed to high temperatures and 1-4 percent partial melt related to adiabatic decompression during mantle upwelling.

Preliminary analytical results for ash and burned soils from the October 2007 southern California wildfires

USGS Publications Warehouse

Plumlee, Geoffrey S.; Martin, Deborah A.; Hoefen, Todd; Kokaly, Raymond F.; Hageman, Philip; Eckberg, Alison; Meeker, Gregory P.; Adams, Monique; Anthony, Michael; Lamothe, Paul J.

2007-01-01

The U.S. Geological Survey (USGS) collected ash and burned soils from about 28 sites in southern California wildfire areas (Harris, Witch, Ammo, Santiago, Canyon and Grass Valley) from Nov. 2 through 9, 2007 (table 1). USGS researchers are applying a wide variety of analytical methods to these samples, with the goal of helping identify characteristics of the ash and soils from wildland and suburban burned areas that may be of concern for their potential to adversely affect water quality, human health, endangered species, and debris-flow or flooding hazards. These studies are part of the Southern California Multi-Hazards Demonstration Project, and preliminary findings are presented here.

Comparison of groundwater flow in Southern California coastal aquifers

USGS Publications Warehouse

Hanson, Randall T.; Izbicki, John A.; Reichard, Eric G.; Edwards, Brian D.; Land, Michael; Martin, Peter

2009-01-01

Maintaining the sustainability of Southern California coastal aquifers requires joint management of surface water and groundwater (conjunctive use). This requires new data collection and analyses (including research drilling, modern geohydrologic investigations, and development of detailed computer groundwater models that simulate the supply and demand components separately), implementation of new facilities (including spreading and injection facilities for artificial recharge), and establishment of new institutions and policies that help to sustain the water resources and better manage regional development.

Evidence of a major fault zone along the California-Nevada state line 35 deg 30 min to 36 deg 30 min north latitude

NASA Technical Reports Server (NTRS)

Liggett, M. A.; Childs, J. F.

1973-01-01

The author has identified the following significant results. Geologic reconnaissance guided by analysis of ERTS-1 and Apollo-9 satellite imagery and intermediate scale photography from X-15 and U-2 aircraft has confirmed the presence of a major fault zone along the California-Nevada state line, between 35 deg 30 min and 36 deg 30 min north latitude. The name Pahrump Fault Zone has been suggested for this feature after the valley in which it is best exposed. Field reconnaissance has indicated the existence of previously unreported faults cutting bedrock along range fronts, and displacing Tertiary and Quaternary basin sediments. Gravity data support the interpretation of regional structural discontinuity along this zone. Individual fault traces within the Pahrump Fault Zone form generally left-stepping en echelon patterns. These fault patterns, the apparent offset of a Laramide age thrust fault, and possible drag folding along a major fault break suggest a component of right lateral displacement. The trend and postulated movement of the Pahrump Fault Zone are similar to the adjacent Las Vegas Shear Zone and Death Valley-Furnace Creek Faults, which are parts of a regional strike slip system in the southern Basin-Range Province.

Oviposition site of the southern torrent salamander (Rhyacotriton variegatus) in northwestern California

Treesearch

Nancy E. Karraker; Lisa M. Ollivier; Garth R. Hodgson

2005-01-01

Oviposition sites and reproductive ecology of the southern-torrent salamander (Rhyacotriton variegatus) remain poorly documented. This species oviposits in cryptic locations making the detection of eggs difficult. Here we describe the discovery of 1 clutch of eggs of R. variegatus from northern California, which further expands our...

Birth weight following pregnancy during the 2003 Southern California wildfires.

PubMed

Holstius, David M; Reid, Colleen E; Jesdale, Bill M; Morello-Frosch, Rachel

2012-09-01

In late October 2003, a series of wildfires exposed urban populations in Southern California to elevated levels of air pollution over several weeks. Previous research suggests that short-term hospital admissions for respiratory outcomes increased specifically as a result of these fires. We assessed the impact of a wildfire event during pregnancy on birth weight among term infants. Using records for singleton term births delivered to mothers residing in California's South Coast Air Basin (SoCAB) during 2001-2005 (n = 886,034), we compared birth weights from pregnancies that took place entirely before or after the wildfire event (n = 747,590) with those where wildfires occurred during the first (n = 60,270), second (n = 39,435), or third (n = 38,739) trimester. The trimester-specific effects of wildfire exposure were estimated using a fixed-effects regression model with several maternal characteristics included as covariates. Compared with pregnancies before and after the wildfires, mean birth weight was estimated to be 7.0 g lower [95% confidence interval (CI): -11.8, -2.2] when the wildfire occurred during the third trimester, 9.7 g lower when it occurred during the second trimester (95% CI: -14.5, -4.8), and 3.3 g lower when it occurred during the first trimester (95% CI: -7.2, 0.6). Pregnancy during the 2003 Southern California wildfires was associated with slightly reduced average birth weight among infants exposed in utero. The extent and increasing frequency of wildfire events may have implications for infant health and development.

75 FR 69057 - Foreign-Trade Zone 226-Merced, Madera, Fresno, and Tulare Counties, California; Site Renumbering...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-10

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board Foreign-Trade Zone 226--Merced, Madera, Fresno, and Tulare Counties, California; Site Renumbering Notice Foreign-Trade Zone 226 was approved by the Foreign-Trade Zones Board on December 22, 1997 (Board Order 946, 63 FR 778-779, 01/07/98) and expanded on...

Strong SH-to-Love wave scattering off the Southern California Continental Borderland

USGS Publications Warehouse

Yu, Chunquan; Zhan, Zhongwen; Hauksson, Egill; Cochran, Elizabeth S.

2017-01-01

Seismic scattering is commonly observed and results from wave propagation in heterogeneous medium. Yet, deterministic characterization of scatterers associated with lateral heterogeneities remains challenging. In this study, we analyze broadband waveforms recorded by the Southern California Seismic Network and observe strongly scattered Love waves following the arrival of teleseismic SH wave. These scattered Love waves travel approximately in the same (azimuthal) direction as the incident SH wave at a dominant period of ~10 s but at an apparent velocity of ~3.6 km/s as compared to the ~11 km/s for the SH wave. Back-projection suggests that this strong scattering is associated with pronounced bathymetric relief in the Southern California Continental Borderland, in particular the Patton Escarpment. Finite-difference simulations using a simplified 2-D bathymetric and crustal model are able to predict the arrival times and amplitudes of major scatterers. The modeling suggests a relatively low shear wave velocity in the Continental Borderland.

Charter Schools Indicators: A Report from the Center on Educational Governance, University of Southern California. CSI-USC 2008

ERIC Educational Resources Information Center

Center on Educational Governance, 2008

2008-01-01

This report, which is the second annual report on charter schools in California by the University of Southern California's (USC's) Center on Educational Governance, offers a unique view of charter school performance. Using both financial and academic data submitted by school districts to the state of California, this report looks well beyond test…

Magnetostratigraphy of displaced Upper Cretaceous strata in southern California

NASA Astrophysics Data System (ADS)

Fry, J. Gilbert; Bottjer, David J.; Lund, Steve P.

1985-09-01

A magnetostratigraphic study of Upper Cretaceous marine strata from the Santa Ana Mountains in southern California has identified a Campanian reversed magnetozone. This reversed interval, corresponding to marine magnetic anomaly 33 34 (Chron 33r) of Campanian age, can be correlated with a Campanian reversed magnetozone that has been reported from strata of the Great Valley Sequence in central California. The Late Cretaceous paleolatitude of the Santa Ana Mountains is estimated from this study to be 26.6°N. This is significantly different from the region's expected Cretaceous paleolatitude of 43.8°N as part of the North American stable craton, and indicates that this region (part of the Peninsular Ranges terrane) was 1900 km farther south in Cretaceous time relative to the stable craton. *Present address: Mobil Oil Corp., P.O. Box 900, Dallas, Texas 75221

Reduction of Potential Fire Behavior in Wildland-urban Interface Communities in Southern California: A Collaborative Approach

Treesearch

Christopher A. Dicus; Michael E. Scott

2006-01-01

This manuscript details a collaborative effort that reduced the risk of wildfire in an affluent, wildland-urban interface community in southern California while simultaneously minimizing the environmental impact to the site. FARSITE simulations illustrated the potential threat to the community of Rancho Santa Fe in San Diego County, California, where multimillion-...

The Optics Institute of Southern California: organizing and implementing outreach effort

NASA Astrophysics Data System (ADS)

Silberman, Donn M.

2003-10-01

The Optics Institute of Southern California is organizing the local educational outreach effort. Working with local optics businesses, society chapters, science discovery centers, K-12, community college and university educators, and others from the global optics education and training community, the OISC is becoming a one-stop clearing house for a wide range of educational outreach activities.

Avifauna in southern California chaparral: seasonal distribution, habitat association, reproductive phenology

Treesearch

William O. Wirtz

1991-01-01

Dates were obtained between February 1969 and October 1979 on the seasonal occurrence, habitat association, reproductive phenology, and relative abundance of avifauna at two study sites in the chaparral community of the San Gabriel Mountains of southern California. The purpose of the study was to collect information on bird species use of this habitat and to document...

33 CFR 165.1131 - Security Zone: Wilson Cove, San Clemente Island, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

... zone is prohibited unless authorized by the Captain of the Port, San Diego, California. Section 165.33 also contains other general requirements. [COTP San Diego Reg. 87-04, 52 FR 18230, May 14, 1987...

33 CFR 165.1131 - Security Zone: Wilson Cove, San Clemente Island, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

... zone is prohibited unless authorized by the Captain of the Port, San Diego, California. Section 165.33 also contains other general requirements. [COTP San Diego Reg. 87-04, 52 FR 18230, May 14, 1987...

33 CFR 165.1131 - Security Zone: Wilson Cove, San Clemente Island, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

... zone is prohibited unless authorized by the Captain of the Port, San Diego, California. Section 165.33 also contains other general requirements. [COTP San Diego Reg. 87-04, 52 FR 18230, May 14, 1987...

33 CFR 165.1131 - Security Zone: Wilson Cove, San Clemente Island, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

... zone is prohibited unless authorized by the Captain of the Port, San Diego, California. Section 165.33 also contains other general requirements. [COTP San Diego Reg. 87-04, 52 FR 18230, May 14, 1987...

33 CFR 165.1131 - Security Zone: Wilson Cove, San Clemente Island, California.

Code of Federal Regulations, 2010 CFR

2010-07-01

... zone is prohibited unless authorized by the Captain of the Port, San Diego, California. Section 165.33 also contains other general requirements. [COTP San Diego Reg. 87-04, 52 FR 18230, May 14, 1987...

CLMSZ, Garnet Mountain area, southern California: A collisionally generated contractional shear zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bracchi, K.A.; Girty, G.H.; Girty, M.S.

1993-04-01

The Harper Creek gneiss (HCg) and Oriflamme Canyon unit (OCu) underlie the central portion of the Cuyamaca Laguna Mountains shear zone (CLMSZ) in and around Garnet Mountain, Peninsular Ranges, California, and may have been deformed during Cretaceous arc-continent collision. U-Pb zircon work and petrological and geochemical analyses suggest that in the Garnet Mountain area, the 140 Ma HCg is derived from granite and granodiorite, whereas the 122 [+-] 1 Ma OCu is a protomylonite derived from a granite. Both units appear to be per aluminous calc-alkaline magmatic arc granitoids. Mineral assemblages suggest uppermost greenschist to lower amphibolite grade conditions duringmore » deformation. In the HCg, S-1hc is a mylonitic gneissosity with a mean attitude of N11W, 60 NE. A mineral streaking lineation lies within the plane of S-1hc and has a mean attitude of 61[degree] N76E. In the OCu, S-1oc strikes about N13W and dips 52 NE and contains a mineral streaking lineation with an attitude of 49 N52E. Dextral and sinistral shear bands, S-2d and S-2s (looking NW), transect S-1hc and S-1oc. S-2d and S-2s strike subparallel to S-1. In the HCg S-2s is weakly developed and dips about 32 NE, whereas S-2d is more dominant and dips about 76 NE. On the OCu these relationships are reversed. S-2d does not cross cut S-2s: hence, the two sets of shear bands are interpreted to be conjugates reflecting NE-SW contraction and subvertical extension during collisional development of the CLMSZ.« less

Paleomagnetic Data Bearing on the Evolution of the Walker Lane Belt Transfer Zone From mid-Miocene to Present: an Investigation of the Inferred Southern and Eastern Boundaries.

NASA Astrophysics Data System (ADS)

Grow, J. S.; Geissman, J. W.; Oldow, J. S.

2008-12-01

The Walker Lane Belt (WLB) transfer zone, which initiated in the mid-Miocene, presently links the Eastern California Shear Zone (ECSZ) in the south to the Central Nevada Seismic Belt (CNSB) and WLB to the east and north, respectively. This transfer zone is part of a diffuse intracontinental deformation zone that accommodates some 25 percent of the current motion between the North American and Pacific plates. The boundary of the transfer system is clear on the northern and western margins but the extent of the system to the south and east is only inferred. The extent of deformation and development of the WLB transfer zone since the mid-Miocene is being examined by a paleomagnetic study of 125 sites that includes Miocene to mid-Pliocene volcanic and shallow intrusive rocks near the inferred southern and eastern boundaries. Results from 39 sites inside and along the southern boundary (i.e. Goldfield Hills, Montezuma Range, Clayton Ridge) show about 30° of clockwise rotation (D = 028.3°, I = 57.8°, α95 = 3.9°, discordant from the expected Neogene direction of D = 358°, I = 55°). The area where 13 of these 39 sites are located (i.e. northern Amargosa Range, eastern Slate Ridge) was previously thought to lie outside of the inferred boundary, yet it also shows about 30° of clockwise rotation (D = 031.2°, I = 52.4°, α95 = 6.7°). Areas along the eastern boundary (i.e. southern San Antonio Range) of the transfer zone are still under investigation; data obtained to date are not internally consistent. Overall, the available paleomagnetic data suggest that the southern extent of the WLB transfer zone was larger than previously expected during the mid-Miocene to mid-Pliocene, and based on previous paleomagnetic, structural, and geodetic studies of the area, support a transition from more diffuse to localized deformation (forming the Mina Deflection) at about 3 Ma.

A new bathyal sipunculan from Southern California, with ecological notes

NASA Astrophysics Data System (ADS)

Thompson, Bruce E.

1980-11-01

Golfingia (Nephasoma) nicolasi n. sp. is described. It is a long, slender species with a filiform introvert that is 6 to 7 times the length of the trunk. The species was often the numerically dominant taxon in samples collected from the San Nicolas Basin, California, and was also callected from several other basins off southern California. Analyses of several collections from the San Nicolas Basin show that the population was spatially patchy; temporal variation was also indicated but only one year was sampled adequately. Average population densities were highest at the base of the slopes descending into the basin from the highly productive Santa Rosa-Cortes Ridge and Tanner Bank. G. nicolasi appears to feed on the large amounts of organic detritus that accumulate from this source.

Crustal deformation in southern California using SAR interferometry

USGS Publications Warehouse

Peltzer, G.; Rosen, P.; Rogez, F.; Hudnut, K.

1997-01-01

By combining pairs of ERS-1/2 SAR images of Southern California spanning long time intervals (1-4 years), we were able to measure the rate of slow deformation processes along faults activated during the Landers 1992 earthquake. Interferograms revealed several centimeters of post-seismic rebound in step-overs of the 1992 break, with a characteristic decay rate of -280 days. We interpreted this process as due to pore fluid flow as pore pressure gradients caused by coseismic stress changes dissipate. The data also revealed evidence of after-slip on different sections of the fault. The southern branches of the 1992 break experienced surface creep producing sharp phase cuts hi the interferometric maps. The same approach was used in the Los Angeles basin, which is currently undergoing NS shortening at a rate of ???8 mm/yr. The tectonic signal in imerferograms of the Los Angeles basin is intermingled with signals due to other sources such as ground subsidence caused by oil and water withdrawal.

Cost-effective fire management for southern California's chaparral wilderness: an analytical procedure

Treesearch

Chris A. Childers; Douglas D. Piirto

1989-01-01

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management...

Are We Segregated and Satisfied? Segregation and Inequality in Southern California Schools

ERIC Educational Resources Information Center

Kucsera, John V.; Siegel-Hawley, Genevieve; Orfield, Gary

2015-01-01

Southern California is facing a demographic transformation that will become characteristic of the nation as a whole in coming decades. In this research, we present a historical review of the region's attempt to address school inequity, recent enrollment and segregation trends, and an investigation of whether segregation still matters. Our results…

76 FR 37646 - Safety Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, City of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, City of Sausalito... Guard will enforce the Fourth of July Fireworks, City of Sausalito annual safety zone. This action is... through, or anchoring in the safety zone, unless authorized by the Patrol Commander (PATCOM). DATES: The...

Health effects of the 2003 Southern California wildfires on children.

PubMed

Künzli, Nino; Avol, Ed; Wu, Jun; Gauderman, W James; Rappaport, Ed; Millstein, Joshua; Bennion, Jonathan; McConnell, Rob; Gilliland, Frank D; Berhane, Kiros; Lurmann, Fred; Winer, Arthur; Peters, John M

2006-12-01

In late October 2003, Southern California wildfires burned more than 3,000 km2. The wildfires produced heavy smoke that affected several communities participating in the University of Southern California Children's Health Study (CHS). To study the acute effects of fire smoke on the health of CHS participants. A questionnaire was used to assess smoke exposure and occurrence of symptoms among CHS high-school students (n = 873; age, 17-18 yr) and elementary-school children (n = 5,551; age, 6-7 yr), in a total of 16 communities. Estimates of particulate matter (PM10) concentrations during the 5 d with the highest fire activity were used to characterize community smoke level. All symptoms (nose, eyes, and throat irritations; cough; bronchitis; cold; wheezing; asthma attacks), medication usage, and physician visits were associated with individually reported exposure differences within communities. Risks increased monotonically with the number of reported smoky days. For most outcomes, reporting rates between communities were also associated with the fire-related PM10 levels. Associations tended to be strongest among those without asthma. Individuals with asthma were more likely to take preventive action, such as wearing masks or staying indoors during the fire. Exposure to wildfire smoke was associated with increased eye and respiratory symptoms, medication use, and physician visits.

FORESHOCKS AND TIME-DEPENDENT EARTHQUAKE HAZARD ASSESSMENT IN SOUTHERN CALIFORNIA.

USGS Publications Warehouse

Jones, Lucile M.

1985-01-01

The probability that an earthquake in southern California (M greater than equivalent to 3. 0) will be followed by an earthquake of larger magnitude within 5 days and 10 km (i. e. , will be a foreshock) is 6 plus or minus 0. 5 per cent (1 S. D. ), and is not significantly dependent on the magnitude of the possible foreshock between M equals 3 and M equals 5. The probability that an earthquake will be followed by an M greater than equivalent to 5. 0 main shock, however, increases with magnitude of the foreshock from less than 1 per cent at M greater than equivalent to 3 to 6. 5 plus or minus 2. 5 per cent (1 S. D. ) at M greater than equivalent to 5. The main shock will most likely occur in the first hour after the foreshock, and the probability that a main shock will occur in the first hour decreases with elapsed time from the occurrence of the possible foreshock by approximately the inverse of time. Thus, the occurrence of an earthquake of M greater than equivalent to 3. 0 in southern California increases the earthquake hazard within a small space-time window several orders of magnitude above the normal background level.

Recent developments in understanding the tectonic evolution of the Southern California offshore area: Implications for earthquake-hazard analysis

USGS Publications Warehouse

Fisher, M.A.; Langenheim, V.E.; Nicholson, C.; Ryan, H.F.; Sliter, R.W.

2009-01-01

During late Mesozoic and Cenozoic time, three main tectonic episodes affected the Southern California offshore area. Each episode imposed its unique structural imprint such that early-formed structures controlled or at least influenced the location and development of later ones. This cascaded structural inheritance greatly complicates analysis of the extent, orientation, and activity of modern faults. These fault attributes play key roles in estimates of earthquake magnitude and recurrence interval. Hence, understanding the earthquake hazard posed by offshore and coastal faults requires an understanding of the history of structural inheritance and modifi-cation. In this report we review recent (mainly since 1987) findings about the tectonic development of the Southern California offshore area and use analog models of fault deformation as guides to comprehend the bewildering variety of offshore structures that developed over time. This report also provides a background in regional tectonics for other chapters in this section that deal with the threat from offshore geologic hazards in Southern California. ?? 2009 The Geological Society of America.

Pleistocene Brawley and Ocotillo Formations: Evidence for initial strike-slip deformation along the San Felipe and San Jacinto fault zonez, Southern California

USGS Publications Warehouse

Kirby, S.M.; Janecke, S.U.; Dorsey, R.J.; Housen, B.A.; Langenheim, V.E.; McDougall, K.A.; Steeley, A.N.

2007-01-01

We examine the Pleistocene tectonic reorganization of the Pacific-North American plate boundary in the Salton Trough of southern California with an integrated approach that includes basin analysis, magnetostratigraphy, and geologic mapping of upper Pliocene to Pleistocene sedimentary rocks in the San Felipe Hills. These deposits preserve the earliest sedimentary record of movement on the San Felipe and San Jacinto fault zones that replaced and deactivated the late Cenozoic West Salton detachment fault. Sandstone and mudstone of the Brawley Formation accumulated between ???1.1 and ???0.6-0.5 Ma in a delta on the margin of an arid Pleistocene lake, which received sediment from alluvial fans of the Ocotillo Formation to the west-southwest. Our analysis indicates that the Ocotillo and Brawley formations prograded abruptly to the east-northeast across a former mud-dominated perennial lake (Borrego Formation) at ???1.1 Ma in response to initiation of the dextral-oblique San Felipe fault zone. The ???25-km-long San Felipe anticline initiated at about the same time and produced an intrabasinal basement-cored high within the San Felipe-Borrego basin that is recorded by progressive unconformities on its north and south limbs. A disconformity at the base of the Brawley Formation in the eastern San Felipe Hills probably records initiation and early blind slip at the southeast tip of the Clark strand of the San Jacinto fault zone. Our data are consistent with abrupt and nearly synchronous inception of the San Jacinto and San Felipe fault zones southwest of the southern San Andreas fault in the early Pleistocene during a pronounced southwestward broadening of the San Andreas fault zone. The current contractional geometry of the San Jacinto fault zone developed after ???0.5-0.6 Ma during a second, less significant change in structural style. ?? 2007 by The University of Chicago. All rights reserved.

Survival of fishers in the southern Sierra Nevada region of California

Treesearch

Richard A. Sweitzer; Craig M. Thompson; Rebecca E. Green; Reginald H. Barrett; Kathryn L. Purcell

2015-01-01

Fishers in the western United States were recently proposed for listing under the U.S. Endangered Species Act because of concerns for loss of suitable habitat and evidence of a diversity of mortality risks that reduce survival. One of 2 remnant populations of fishers in California is in the southern Sierra Nevada region, where we studied them at 2 research sites in the...

Net dextral slip, Neogene San Gregorio–Hosgri fault zone, coastal California: Geologic evidence and tectonic implications

USGS Publications Warehouse

Dickinson, William R.; Ducea, M.; Rosenberg, Lewis I.; Greene, H. Gary; Graham, Stephan A.; Clark, Joseph C.; Weber, Gerald E.; Kidder, Steven; Ernst, W. Gary; Brabb, Earl E.

2005-01-01

Reinterpretation of onshore and offshore geologic mapping, examination of a key offshore well core, and revision of cross-fault ties indicate Neogene dextral strike slip of 156 ± 4 km along the San Gregorio–Hosgri fault zone, a major strand of the San Andreas transform system in coastal California. Delineating the full course of the fault, defining net slip across it, and showing its relationship to other major tectonic features of central California helps clarify the evolution of the San Andreas system.San Gregorio–Hosgri slip rates over time are not well constrained, but were greater than at present during early phases of strike slip following fault initiation in late Miocene time. Strike slip took place southward along the California coast from the western fl ank of the San Francisco Peninsula to the Hosgri fault in the offshore Santa Maria basin without significant reduction by transfer of strike slip into the central California Coast Ranges. Onshore coastal segments of the San Gregorio–Hosgri fault include the Seal Cove and San Gregorio faults on the San Francisco Peninsula, and the Sur and San Simeon fault zones along the flank of the Santa Lucia Range.Key cross-fault ties include porphyritic granodiorite and overlying Eocene strata exposed at Point Reyes and at Point Lobos, the Nacimiento fault contact between Salinian basement rocks and the Franciscan Complex offshore within the outer Santa Cruz basin and near Esalen on the flank of the Santa Lucia Range, Upper Cretaceous (Campanian) turbidites of the Pigeon Point Formation on the San Francisco Peninsula and the Atascadero Formation in the southern Santa Lucia Range, assemblages of Franciscan rocks exposed at Point Sur and at Point San Luis, and a lithic assemblage of Mesozoic rocks and their Tertiary cover exposed near Point San Simeon and at Point Sal, as restored for intrabasinal deformation within the onshore Santa Maria basin.Slivering of the Salinian block by San Gregorio–Hosgri displacements

76 FR 42725 - Notice of Availability of the Record of Decision for the Southern California Edison Company...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-19

... Devers-Palo Verde No. 2 Transmission Line Project, California AGENCY: Bureau of Land Management, Interior... the Devers-Palo Verde No. 2 Transmission Line Project located in southern California. The Palm Springs..., located near the Palo Verde Nuclear Generating Station west of Phoenix, Arizona. A 50-mile 230-kV...

CCIS Experiment : Comparing Transit Information Retrieval Modes at the Southern California Rapid Transit District

DOT National Transportation Integrated Search

1984-03-01

This report documents the results of a controlled experiment performed in the Telephone Information Section of the Marketing Department at the Southern California Rapid Transit District (SCRTD) in Los Angeles. The Telephone Information Section is the...

Time-dependent gravity in Southern California, May 1974 to April 1979

NASA Technical Reports Server (NTRS)

Whitcomb, J. H.; Franzen, W. O.; Given, J. W.; Pechmann, J. C.; Ruff, L. J.

1980-01-01

The Southern California gravity survey, begun in May 1974 to obtain high spatial and temporal density gravity measurements to be coordinated with long-baseline three dimensional geodetic measurements of the Astronomical Radio Interferometric Earth Surveying project, is presented. Gravity data was obtained from 28 stations located in and near the seismically active San Gabriel section of the Southern California Transverse Ranges and adjoining San Andreas Fault at intervals of one to two months using gravity meters relative to a base station standard meter. A single-reading standard deviation of 11 microGal is obtained which leads to a relative deviation of 16 microGal between stations, with data averaging reducing the standard error to 2 to 3 microGal. The largest gravity variations observed are found to correlate with nearby well water variations and smoothed rainfall levels, indicating the importance of ground water variations to gravity measurements. The largest earthquake to occur during the survey, which extended to April, 1979, is found to be accompanied in the station closest to the earthquake by the largest measured gravity changes that cannot be related to factors other than tectonic distortion.

Adjoint tomography of Empirical Green's functions from ambient noise in Southern California

NASA Astrophysics Data System (ADS)

Wang, K.; Liu, Q.; Yang, Y.; Basini, P.; Tape, C.

2017-12-01

We construct a new shear-wave velocity (Vsv) model in Southern California by adjoint tomography of Rayleigh-wave Empirical Green's functions at 5-50 s period from Z-Z component ambient noise cross-correlations. The initial model of our adjoint tomography is the isotropic Vs model M16 from Tape et al. [2010], which is generated by three-component body and surface waves at 2-30 s period from local earthquake data. Synthetic Green's functions (SGFs) from M16 show a good agreement with the Empirical Green's functions (EGFs) from ambient noise at 5-50 s and 10-50 s period bands, but have an average 1.75 s advance in time at 20-50 s. By minimizing the traveltime differences between the EGFs and SGFs using gradient-based algorithm, the initial model is refined and improved and the total misfits is reduced from the initial 1.75s to its convergent point of 0.33 s after five iterations. The final Vsv model fits EGF waveforms better than the initial model at all the three frequency bands with smaller misfit distributions. Our new Vsv model reveals some new features in the mid- and lower-crust, mainly including: (1) the mean speed of lower crust is slowed down by about 5%; (2) In the Los Angeles Basin and its Northern area, the speed is higher than the initial model throughout the crust; (3) beneath the westernmost Peninsular Range Batholith (PRB) and Sierra Nevada Batholith (SNB), we observe high shear velocities in the lower crust; (4) a shallow high-velocity zone in the mid-crust are observed beneath Salton Trough Basin. Our model also shows refined lateral velocity gradient across PRB, SNB, San Andreas Fault (SAF), which helps to understand the west-east compositional boundary in PRB, SNB, and the dip angle and the depth extent of SAF. Our study demonstrates the feasibility of adjoint tomography of ambient noise data in southern California, which is an important complement to earthquake data. The numerical solver used in adjoint tomography can provide more accurate

Sensitive species of snakes, frogs, and salamanders in southern California conifer forest areas: status and management

Treesearch

Glenn R. Stewart; Mark R. Jennings; Robert H. Jr. Goodman

2005-01-01

At least 35 species of amphibians and reptiles occur regularly in the conifer forest areas of southern California. Twelve of them have some or all of their populations identified as experiencing some degree of threat. Among the snakes, frogs, and salamanders that we believe need particular attention are the southern rubber boa (Charina bottae umbratica...

High-resolution mapping of two large-scale transpressional fault zones in the California Continental Borderland: Santa Cruz-Catalina Ridge and Ferrelo faults

NASA Astrophysics Data System (ADS)

Legg, Mark R.; Kohler, Monica D.; Shintaku, Natsumi; Weeraratne, Dayanthie S.

2015-05-01

New mapping of two active transpressional fault zones in the California Continental Borderland, the Santa Cruz-Catalina Ridge fault and the Ferrelo fault, was carried out to characterize their geometries, using over 4500 line-km of new multibeam bathymetry data collected in 2010 combined with existing data. Faults identified from seafloor morphology were verified in the subsurface using existing seismic reflection data including single-channel and multichannel seismic profiles compiled over the past three decades. The two fault systems are parallel and are capable of large lateral offsets and reverse slip during earthquakes. The geometry of the fault systems shows evidence of multiple segments that could experience throughgoing rupture over distances exceeding 100 km. Published earthquake hypocenters from regional seismicity studies further define the lateral and depth extent of the historic fault ruptures. Historical and recent focal mechanisms obtained from first-motion and moment tensor studies confirm regional strain partitioning dominated by right slip on major throughgoing faults with reverse-oblique mechanisms on adjacent structures. Transpression on west and northwest trending structures persists as far as 270 km south of the Transverse Ranges; extension persists in the southern Borderland. A logjam model describes the tectonic evolution of crustal blocks bounded by strike-slip and reverse faults which are restrained from northwest displacement by the Transverse Ranges and the southern San Andreas fault big bend. Because of their potential for dip-slip rupture, the faults may also be capable of generating local tsunamis that would impact Southern California coastlines, including populated regions in the Channel Islands.

Instability model for recurring large and great earthquakes in southern California

USGS Publications Warehouse

Stuart, W.D.

1985-01-01

The locked section of the San Andreas fault in southern California has experienced a number of large and great earthquakes in the past, and thus is expected to have more in the future. To estimate the location, time, and slip of the next few earthquakes, an earthquake instability model is formulated. The model is similar to one recently developed for moderate earthquakes on the San Andreas fault near Parkfield, California. In both models, unstable faulting (the earthquake analog) is caused by failure of all or part of a patch of brittle, strain-softening fault zone. In the present model the patch extends downward from the ground surface to about 12 km depth, and extends 500 km along strike from Parkfield to the Salton Sea. The variation of patch strength along strike is adjusted by trial until the computed sequence of instabilities matches the sequence of large and great earthquakes since a.d. 1080 reported by Sieh and others. The last earthquake was the M=8.3 Ft. Tejon event in 1857. The resulting strength variation has five contiguous sections of alternately low and high strength. From north to south, the approximate locations of the sections are: (1) Parkfield to Bitterwater Valley, (2) Bitterwater Valley to Lake Hughes, (3) Lake Hughes to San Bernardino, (4) San Bernardino to Palm Springs, and (5) Palm Springs to the Salton Sea. Sections 1, 3, and 5 have strengths between 53 and 88 bars; sections 2 and 4 have strengths between 164 and 193 bars. Patch section ends and unstable rupture ends usually coincide, although one or more adjacent patch sections may fail unstably at once. The model predicts that the next sections of the fault to slip unstably will be 1, 3, and 5; the order and dates depend on the assumed length of an earthquake rupture in about 1700. ?? 1985 Birkha??user Verlag.

Biomedical application in space, pilot program in the southern California region

NASA Technical Reports Server (NTRS)

Kelton, A. A.

1979-01-01

A pilot program is presented which was to promote utilization of the Shuttle/Spacelab for medical and biological research applied to terrestrial needs. The program was limited to the Southern California region and consisted of the following five tasks: (1) preparation of educational materials; (2) identification of principal investigators; (3) initial contact and visit; (4)development of promising applications; and (5) evaluation of regional program methodology.

Thermochronology of Cretaceous batholithic rocks in the northern Peninsular Ranges batholith, southern California: Implications for the Late Cretaceous tectonic evolution of southern California

USGS Publications Warehouse

Miggins, Daniel P.; Premo, Wayne R.; Snee, Lawrence W; Yeoman, Ross; Naeaer, Nancy D.; Naeser, Charles W.; Morton, Douglas M.

2014-01-01

The thermochronology for several suites of Mesozoic metamorphic and plutonic rocks collected throughout the northern Peninsular Ranges batholith (PRB) was studied as part of a collaborative isotopic study to further our understanding of the magmatic and tectonic history of southern California. These sample suites include: a traverse through the plutonic rocks across the northern PRB (N = 29), a traverse across a central structural and metamorphic transition zone of mainly metasedimentary rocks at Searl ridge (N = 20), plutonic samples from several drill cores (N = 7) and surface samples (N = 2) from the Los Angeles Basin, a traverse across the Eastern Peninsular Ranges mylonite zone (N = 6), and a suite of plutonic samples collected across the northern PRB (N = 13) from which only biotite 40Ar/39Ar ages were obtained. These geochronologic data help to characterize five major petrologic, geochemical, and isotopic zonations of the PRB (western zone, WZ; western transition zone, WTZ; eastern transition zone, ETZ; eastern zone, EZ; and upper-plate zone, UPZ).Apparent cooling rates were calculated using U-Pb zircon (zr) and titanite (sphene) ages; 40Ar/39Ar ages from hornblende (hbl), biotite (bi), and K-feldspar (Kf); and apatite fission-track (AFT) ages from the same samples. The apparent cooling rates across the northern PRB vary from relatively rapid in the west (zr-hbl ~210 °C/m.y.; zr-bio ~160 °C/m.y.; zr-Kf ~80 °C/m.y.) to less rapid in the central (zr-hb ~280 °C/m.y.; zr-bio ~90 °C/m.y.; zr-Kf ~60 °C/m.y.) and eastern (zr-hbl ~185 °C/m.y.; zr-bio ~180 °C/m.y.; zr-Kf ~60 °C/m.y.) zones. An exception in the eastern zone, the massive San Jacinto pluton, appears to have cooled very rapidly (zr-bio ~385 °C/m.y.). Apparent cooling rates for the UPZ samples are consistently slower in comparison (~25–45 °C/m.y.), regardless of which geochronometers are used.Notable characteristics of the various ages from different dating methods include: (1) Zircon

Strain Localisation at Rift Segment Boundaries: An Example from the Bocana Transfer Zone in Central Baja California, Mexico

NASA Astrophysics Data System (ADS)

Seiler, C.; Gleadow, A. J.; Kohn, B. P.

2012-12-01

Rifts are commonly segmented into several hundred kilometre long zones of opposing upper-plate transport direction with boundaries defined by accommodation and transfer zones. A number of such rift segments have been recognized in the northern Gulf of California, a youthful oceanic basin that is currently undergoing the rift-drift transition. However, detailed field studies have so far failed to identify suitable structures that could accommodate the obvious deformation gradients between different rift segments, and the nature of strain transfer at segment boundaries remains enigmatic. The situation is even less clear in central and southern Baja California, where a number of rift segments have been hypothesized but it is unknown whether the intervening segment boundaries facilitate true reversals in the upper-plate transport direction, or whether they simply accommodate differences in the timing, style or magnitude of deformation. The Bocana transfer zone (BTZ) in central Baja California is a linear, WNW-ESE striking structural discontinuity separating two rift segments with different magnitudes and styles of extensional deformation. North of the BTZ, the Libertad fault is part of the Main Gulf Escarpment, which represents the breakaway fault that separates the Gulf of California rift to the east from the relatively stable western portion of the Baja peninsula. The N-striking Libertad escarpment developed during the Late Miocene (~10-8Ma) and exhibits a topographic relief of ca. 1,000m along a strike-length of ca. 50km. Finite displacement decreases from ~1000m in the central fault segment to ~500m further south, where the fault bends SE and merges with the BTZ. In the hanging wall of the Libertad fault, a series of W-tilted horsts are bound along their eastern margins by two moderate-displacement E-dipping normal faults. South of the BTZ, extension was much less than further north, which explains the comparatively subdued relief and generally shallower tilt of

Influence of the invasive goldspotted oak borer on fuel loading in southern California

Treesearch

Tom W. Coleman

2015-01-01

The exotic goldspotted oak borer (GSOB), Agrilus auroguttatus (Coleoptera: Buprestidae), continues to cause elevated oak mortality in southern California. Initial GSOB research was directed at developing an integrated pest management program. However, little research has examined the secondary impacts associated with this invasive pest. My primary...

78 FR 77447 - California Wind Energy Association, First Solar, Inc. v. California Independent System Operator...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... Energy Association, First Solar, Inc. v. California Independent System Operator Corporation, Southern...), California Wind Energy Association and First Solar, Inc. (collectively, Complainants) filed a formal complaint against the California Independent System Operator Corporation (CAISO) and Southern California...

Uncertainties in Earthquake Loss Analysis: A Case Study From Southern California

NASA Astrophysics Data System (ADS)

Mahdyiar, M.; Guin, J.

2005-12-01

Probabilistic earthquake hazard and loss analyses play important roles in many areas of risk management, including earthquake related public policy and insurance ratemaking. Rigorous loss estimation for portfolios of properties is difficult since there are various types of uncertainties in all aspects of modeling and analysis. It is the objective of this study to investigate the sensitivity of earthquake loss estimation to uncertainties in regional seismicity, earthquake source parameters, ground motions, and sites' spatial correlation on typical property portfolios in Southern California. Southern California is an attractive region for such a study because it has a large population concentration exposed to significant levels of seismic hazard. During the last decade, there have been several comprehensive studies of most regional faults and seismogenic sources. There have also been detailed studies on regional ground motion attenuations and regional and local site responses to ground motions. This information has been used by engineering seismologists to conduct regional seismic hazard and risk analysis on a routine basis. However, one of the more difficult tasks in such studies is the proper incorporation of uncertainties in the analysis. From the hazard side, there are uncertainties in the magnitudes, rates and mechanisms of the seismic sources and local site conditions and ground motion site amplifications. From the vulnerability side, there are considerable uncertainties in estimating the state of damage of buildings under different earthquake ground motions. From an analytical side, there are challenges in capturing the spatial correlation of ground motions and building damage, and integrating thousands of loss distribution curves with different degrees of correlation. In this paper we propose to address some of these issues by conducting loss analyses of a typical small portfolio in southern California, taking into consideration various source and ground

Factors influencing the variation in capture rates of shrews in southern California, USA

USGS Publications Warehouse

Laakkonen, Juha; Fisher, Robert N.; Case, Ted J.

2003-01-01

We examined the temporal variation in capture rates of shrewsNotiosorex crawfordi (Coues, 1877) and Sorex ornatus (Merriam, 1895) in 20 sites representing fragmented and continuous habitats in southern California, USA. InN. crawfordi, the temporal variation was significantly correlated with the mean capture rates. Of the 6 landscape variables analyzed (size of the landscape, size of the sample area, altitude, edge, longitude and latitude), sample area was positively correlated with variation in capture rates ofN. crawfordi. InS. ornatus, longitude was negatively correlated with variation in capture rates. Analysis of the effect of precipitation on the short- and long-term capture rates at 2 of the sites showed no correlation between rainfall and capture rates of shrews even though peak number of shrews at both sites were reached during the year of highest amount of rainfall. A key problem confounding capture rates of shrews in southern California is the low overall abundance of both shrew species in all habitats and seasons.

Habitat fragmentation in coastal southern California disrupts genetic connectivity in the cactus wren (Campylorhynchus brunneicapillus)

USGS Publications Warehouse

Barr, Kelly R.; Kus, Barbara E.; Preston, Kristine; Howell, Scarlett; Perkins, Emily; Vandergast, Amy

2015-01-01

Achieving long-term persistence of species in urbanized landscapes requires characterizing population genetic structure to understand and manage the effects of anthropogenic disturbance on connectivity. Urbanization over the past century in coastal southern California has caused both precipitous loss of coastal sage scrub habitat and declines in populations of the cactus wren (Campylorhynchus brunneicapillus). Using 22 microsatellite loci, we found that remnant cactus wren aggregations in coastal southern California comprised 20 populations based on strict exact tests for population differentiation, and 12 genetic clusters with hierarchical Bayesian clustering analyses. Genetic structure patterns largely mirrored underlying habitat availability, with cluster and population boundaries coinciding with fragmentation caused primarily by urbanization. Using a habitat model we developed, we detected stronger associations between habitat-based distances and genetic distances than Euclidean geographic distance. Within populations, we detected a positive association between available local habitat and allelic richness and a negative association with relatedness. Isolation-by-distance patterns varied over the study area, which we attribute to temporal differences in anthropogenic landscape development. We also found that genetic bottleneck signals were associated with wildfire frequency. These results indicate that habitat fragmentation and alterations have reduced genetic connectivity and diversity of cactus wren populations in coastal southern California. Management efforts focused on improving connectivity among remaining populations may help to ensure population persistence.

Evidence for nitrogen saturation in the San Bernardino Mountains in southern California

Treesearch

Mark A. Fenn; Mark A. Poth; Dale W. Johnson

1996-01-01

Elevated N deposition has occurred in the Los Angeles Basin in southern California for at least the last 40 years. Elevated streamwater NO; fluxes and high nitric oxide (NO) fluxes from soil, indicators of N saturation, have recently been reported for chaparral watersheds exposed to chronic N deposition in the San Gabriel Mountains north/northeast of Los Angeles. A...

Potential earthquake faults offshore Southern California, from the eastern Santa Barbara Channel south to Dana Point

USGS Publications Warehouse

Fisher, M.A.; Sorlien, C.C.; Sliter, R.W.

2009-01-01

Urban areas in Southern California are at risk from major earthquakes, not only quakes generated by long-recognized onshore faults but also ones that occur along poorly understood offshore faults. We summarize recent research findings concerning these lesser known faults. Research by the U.S. Geological Survey during the past five years indicates that these faults from the eastern Santa Barbara Channel south to Dana Point pose a potential earthquake threat. Historical seismicity in this area indicates that, in general, offshore faults can unleash earthquakes having at least moderate (M 5-6) magnitude. Estimating the earthquake hazard in Southern California is complicated by strain partitioning and by inheritance of structures from early tectonic episodes. The three main episodes are Mesozoic through early Miocene subduction, early Miocene crustal extension coeval with rotation of the Western Transverse Ranges, and Pliocene and younger transpression related to plate-boundary motion along the San Andreas Fault. Additional complication in the analysis of earthquake hazards derives from the partitioning of tectonic strain into strike-slip and thrust components along separate but kinematically related faults. The eastern Santa Barbara Basin is deformed by large active reverse and thrust faults, and this area appears to be underlain regionally by the north-dipping Channel Islands thrust fault. These faults could produce moderate to strong earthquakes and destructive tsunamis. On the Malibu coast, earthquakes along offshore faults could have left-lateral-oblique focal mechanisms, and the Santa Monica Mountains thrust fault, which underlies the oblique faults, could give rise to large (M ??7) earthquakes. Offshore faults near Santa Monica Bay and the San Pedro shelf are likely to produce both strike-slip and thrust earthquakes along northwest-striking faults. In all areas, transverse structures, such as lateral ramps and tear faults, which crosscut the main faults, could

Steelhead of the south-central/southern California coast: Population characterization for recovery planning

USGS Publications Warehouse

Boughton, David A.; Adams, P.B.; Anderson, E.; Fusaro, Craig; Keller, E.; Kelley, Elsie; Lentsch, Leo; Nielsen, J. L.; Perry, Katie; Regan, Helen; Swift, C.; Watson, Fred

2006-01-01

This report by the National Marine Fisheries Service applies a formal evaluation framework to the problem of delineating Oncorhynchus mykiss populations in the South-Central/Southern California Coast recovery domain, in support of recovery planning under the Endangered Species Act.

Detecting the limits of northern and southern lineages of tanoak in northern California

Treesearch

Eduardo Sandoval-Castro; Richard S. Dodd

2015-01-01

Two chloroplast lineages of tanoak (Notholithocarpus densiflorus) meet between Korbel and Hoopa in the North Coast of California. Our earlier work suggests these lineages arose from southern and northern glacial refugia and this region represents their colonizing fronts. Earlier, we detected only one population of mixed lineages, suggesting that...

Applying remote sensing measurements of phenology to southern California vegetation

NASA Astrophysics Data System (ADS)

Willis, K. S.; Gillespie, T. W.

2012-12-01

Monitoring vegetation phenology can be used to assess the impacts of climate change on a localized region. This study aims to determine the most applicable remote sensing method for monitoring phenological changes in the largest urban National Park in the US: the Santa Monica Mountains of southern California. This is achieved by comparing the Normalized Difference Vegetation Index (NDVI), considered applicable to Mediterranean-type ecosystems due to the low amount of greenness present in the vegetation, with relative spectral mixture analysis (RMSA). RMSA is a technique developed to measure temporal changes in green vegetation (GV), nonphotosynthetic vegetation plus litter (NPV), and snow cover designed for the south-central US. This study analyzes areas of natural vegetation in the Santa Monica Mountains using MODIS imagery by comparing GV and NPV indices derived from RMSA with the classic NDVI. The phenological transition dates of focus here include: (1) greenup, the date of onset of photosynthetic activity; (2) maturity, the date at which plant green leaf area is maximum; (3) senescence, the date at which photosynthetic activity and green leaf area begin to rapidly decrease; (4) dormancy, the date at which physiological activity becomes near zero. Overall, this study tests the application of RMSA to a new environment, compares these results to those derived from NDVI, and provides insight regarding the impacts of climate change on southern California phenological cycles.

Health Effects of the 2003 Southern California Wildfires on Children

PubMed Central

Künzli, Nino; Avol, Ed; Wu, Jun; Gauderman, W. James; Rappaport, Ed; Millstein, Joshua; Bennion, Jonathan; McConnell, Rob; Gilliland, Frank D.; Berhane, Kiros; Lurmann, Fred; Winer, Arthur; Peters, John M.

2006-01-01

Rationale: In late October 2003, Southern California wildfires burned more than 3,000 km2. The wildfires produced heavy smoke that affected several communities participating in the University of Southern California Children's Health Study (CHS). Objectives: To study the acute effects of fire smoke on the health of CHS participants. Methods: A questionnaire was used to assess smoke exposure and occurrence of symptoms among CHS high-school students (n = 873; age, 17–18 yr) and elementary-school children (n = 5,551; age, 6–7 yr), in a total of 16 communities. Estimates of particulate matter (PM10) concentrations during the 5 d with the highest fire activity were used to characterize community smoke level. Main Results: All symptoms (nose, eyes, and throat irritations; cough; bronchitis; cold; wheezing; asthma attacks), medication usage, and physician visits were associated with individually reported exposure differences within communities. Risks increased monotonically with the number of reported smoky days. For most outcomes, reporting rates between communities were also associated with the fire-related PM10 levels. Associations tended to be strongest among those without asthma. Individuals with asthma were more likely to take preventive action, such as wearing masks or staying indoors during the fire. Conclusions: Exposure to wildfire smoke was associated with increased eye and respiratory symptoms, medication use, and physician visits. PMID:16946126

Are hotspots of evolutionary potential adequately protected in southern California?

USGS Publications Warehouse

Vandergast, A.G.; Bohonak, A.J.; Hathaway, S.A.; Boys, J.; Fisher, R.N.

2008-01-01

Reserves are often designed to protect rare habitats, or "typical" exemplars of ecoregions and geomorphic provinces. This approach focuses on current patterns of organismal and ecosystem-level biodiversity, but typically ignores the evolutionary processes that control the gain and loss of biodiversity at these and other levels (e.g., genetic, ecological). In order to include evolutionary processes in conservation planning efforts, their spatial components must first be identified and mapped. We describe a GIS-based approach for explicitly mapping patterns of genetic divergence and diversity for multiple species (a "multi-species genetic landscape"). Using this approach, we analyzed mitochondrial DNA datasets from 21 vertebrate and invertebrate species in southern California to identify areas with common phylogeographic breaks and high intrapopulation diversity. The result is an evolutionary framework for southern California within which patterns of genetic diversity can be analyzed in the context of historical processes, future evolutionary potential and current reserve design. Our multi-species genetic landscapes pinpoint six hotspots where interpopulation genetic divergence is consistently high, five evolutionary hotspots within which genetic connectivity is high, and three hotspots where intrapopulation genetic diversity is high. These 14 hotspots can be grouped into eight geographic areas, of which five largely are unprotected at this time. The multi-species genetic landscape approach may provide an avenue to readily incorporate measures of evolutionary process into GIS-based systematic conservation assessment and land-use planning.

Conserving connectivity: some lessons from mountain lions in southern California.

PubMed

Morrison, Scott A; Boyce, Walter M

2009-04-01

Habitat corridors can be essential for persistence of wildlife populations in fragmented landscapes. Although much research has focused on identifying species and places critical for conservation action, the conservation literature contains surprisingly few examples of corridors that actually have been protected and so provides little guidance for moving from planning through implementation. We examined a case study from southern California that combines monitoring of radio-collared mountain lions (Puma concolor) with an assessment of land-protection efforts to illustrate lessons learned while attempting to maintain ecological connectivity in a rapidly urbanizing landscape. As in many places, conservation scientists have provided science-based maps of where conservation efforts should focus. But implementing corridors is a business decision based not solely on ecological information but also on cost, opportunity cost, investment risk, and other feasibility considerations. Here, the type and pattern of development is such that key connections will be lost unless they are explicitly protected. Keeping pace with conversion, however, has been difficult, especially because conservation efforts have been limited to traditional parcel-by-parcel land-protection techniques. The challenges of and trade-offs in implementation make it clear that in southern California, connectivity cannot be bought one parcel at a time. Effective land-use plans and policies that incorporate conservation principles, such as California's Natural Communities Conservation Planning program, are needed to support the retention of landscape permeability. Lessons from this study have broad application, especially as a precautionary tale for places where such extensive and intensive development has not yet occurred. Given how limiting resources are for biodiversity conservation, conservationists must be disciplined about where and how they attempt corridor protection: in rapidly fragmenting landscapes

Projecting 21st century coastal cliff retreat in Southern California

NASA Astrophysics Data System (ADS)

Limber, P. W.; Barnard, P.; Erikson, L. H.; Vitousek, S.

2016-12-01

In California, sea level is expected to rise over 1 m by 2100, with extreme projections approaching 3 m. Sea level rise (SLR) increases the frequency, severity, and duration of wave impacts on coastal cliffs, potentially accelerating cliff retreat rates. To assess the future risk to cliff-top infrastructure, densely populated Southern California cities like Los Angeles and San Diego require estimates of coastal retreat over long time (multi-decadal) and large spatial (>100 km) scales. We developed a suite of eight coastal cliff retreat models, ranging in complexity from empirical 1-D representations of cliff response to wave impacts to more intricate 2-D process-based models integrated with artificial neural networks. The ensemble produces a comprehensive estimate of time-averaged coastal cliff retreat with uncertainty, is applicable to different geological environments, and is flexible in application depending on processing power, available data, and/or available time (e.g. if processing power and time are limited, the fast 1-D models can be used as a `rapid assessment' tool). Global-to-local nested wave models provided the hindcasts (1980-2010) and forecasts (2010-2100) used to force the models, and waves were applied in combination with eight SLR scenarios ranging from 0.25 m to 2 m. In the more detailed models, tides, non-tidal residuals, and storm surge were included for the hindcast and forecast periods. For model calibration, a new automated cliff edge extraction routine was used to estimate historical cliff retreat rates from LiDAR data. Initial model application to Southern California suggests that 1 m of SLR during the 21st century will cause cliff retreat rates to increase on average by over 50% relative to historical rates. Model results also demonstrate how small-scale, episodic cliff failure events can coalesce through time into spatially uniform, long-term cliff retreat signals.

Onshore and offshore geologic map of the Coal Oil Point area, southern California

USGS Publications Warehouse

Dartnell, Pete; Conrad, James E.; Stanley, Richard G.; Guy R. Cochrane, Guy R.

2011-01-01

Geologic maps that span the shoreline and include both onshore and offshore areas are potentially valuable tools that can lead to a more in depth understanding of coastal environments. Such maps can contribute to the understanding of shoreline change, geologic hazards, both offshore and along-shore sediment and pollutant transport. They are also useful in assessing geologic and biologic resources. Several intermediate-scale (1:100,000) geologic maps that include both onshore and offshore areas (herein called onshore-offshore geologic maps) have been produced of areas along the California coast (see Saucedo and others, 2003; Kennedy and others, 2007; Kennedy and Tan, 2008), but few large-scale (1:24,000) maps have been produced that can address local coastal issues. A cooperative project between Federal and State agencies and universities has produced an onshore-offshore geologic map at 1:24,000 scale of the Coal Oil Point area and part of the Santa Barbara Channel, southern California (fig. 1). As part of the project, the U.S. Geological Survey (USGS) and the California Geological Survey (CGS) hosted a workshop (May 2nd and 3rd, 2007) for producers and users of coastal map products (see list of participants) to develop a consensus on the content and format of onshore-offshore geologic maps (and accompanying GIS files) so that they have relevance for coastal-zone management. The USGS and CGS are working to develop coastal maps that combine geospatial information from offshore and onshore and serve as an important tool for addressing a broad range of coastal-zone management issues. The workshop was divided into sessions for presentations and discussion of bathymetry and topography, geology, and habitat products and needs of end users. During the workshop, participants reviewed existing maps and discussed their merits and shortcomings. This report addresses a number of items discussed in the workshop and details the onshore and offshore geologic map of the Coal Oil

Eddy properties in the Southern California Current System

NASA Astrophysics Data System (ADS)

Chenillat, Fanny; Franks, Peter J. S.; Capet, Xavier; Rivière, Pascal; Grima, Nicolas; Blanke, Bruno; Combes, Vincent

2018-05-01

The California Current System (CCS) is an eastern boundary upwelling system characterized by strong eddies that are often generated at the coast. These eddies contribute to intense, long-distance cross-shelf transport of upwelled water with enhanced biological activity. However, the mechanisms of formation of such coastal eddies, and more importantly their capacity to trap and transport tracers, are poorly understood. Their unpredictability and strong dynamics leave us with an incomplete picture of the physical and biological processes at work, their effects on coastal export, lateral water exchange among eddies and their surrounding waters, and how long and how far these eddies remain coherent structures. Focusing our analysis on the southern part of the CCS, we find a predominance of cyclonic eddies, with a 25-km radius and a SSH amplitude of 6 cm. They are formed near shore and travel slightly northwest offshore for 190 days at 2 km day-1. We then study one particular, representative cyclonic eddy using a combined Lagrangian and Eulerian numerical approach to characterize its kinematics. Formed near shore, this eddy trapped a core made up of 67% California Current waters and 33% California Undercurrent waters. This core was surrounded by other waters while the eddy detached from the coast, leaving the oldest waters at the eddy's core and the younger waters toward the edge. The eddy traveled several months as a coherent structure, with only limited lateral exchange within the eddy.

Possible Climate Change Influences on Continued Reduction of Dense Fog in Southern California

NASA Astrophysics Data System (ADS)

Ladochy, S.; Witiw, M.

2010-07-01

Dense fog appears to be decreasing in many parts of the world, especially in cities. An earlier study showed that dense fog (visibility < 400 m) was disappearing in the urban southern California area as well. Using hourly data from 1948 to the present, we looked at the relationship between fog events and contributing factors in the region along with trends over time. We showed that the decrease in dense fog events could be explained mainly by declining particulate levels, Pacific SSTs, and increased urban warming. Dense fog is most prevalent along the coast and decreases rapidly inland, so the influence of the Pacific should be large. In particular, the Pacific Decadal Oscillation (PDO) and the Southern Oscillation signals can be seen in fog frequencies as well as in the contributing factors. Results show a decrease in the occurrence of dense fog at two airports in close proximity to the Pacific Ocean, LAX and LGB. Occurrence of the frequency of low visibilities at these two locations was highly correlated with the phases of the PDO. While examining data from LAX, we saw a frequency of dense fog that reached over 300 hours in 1950, but occurrence was down to zero in 1997. Since 1997, there has been a bit of a recovery with both 2008 and 2009 recording over 30 hours of dense fog each. In the present study, we continue to examine the relationships that control the frequency of dense fog in coastal southern California. To remove urban influence, we also included Vandenberg Air Force Base, located in a relatively sparsely populated area. While particulates, urban heat island and Pacific SSTs are all contributing factors, we now speculate on the direct and indirect influences of climate change on continued decreases in dense fog. Case studies of local and regional dense fog in southern California point to the importance of strong, low inversions and to a lesser contributor, Santa Ana winds. Both are associated with large-scale atmospheric circulation patterns, which

Southern California Bight 2003 Regional Monitoring Program: V. water quality

USGS Publications Warehouse

Nezlin, Nikolay P.; DiGiacomo, Paul M.; Weisberg, Stephen B.; Diehl, Dario W.; Warrick, Jonathan A.; Mengel, Michael J.; Jones, Burton H.; Reifel, Kristen M.; Johnson, Scott C.; Ohlmann, J. Carter; Washburn, Libe; Terrill, Eric J.

2007-01-01

within the Southern California Bight nearshore zone, and persisting over the entire duration of the post-storm sampling period (at least 3 days). - The spatial and temporal extent of the portion of the plume with contaminants was far less than that of the turbidity plume, typically representing - Pseudo-nitzschia, a harmful algae that produces domoic acid, was found to be more abundant than previously reported. - Accurately describing stormwater runoff plumes requires a combination of in situ and remote sensing assessment tools, with satellite data providing valuable synoptic information. From these conclusions, the following recommendations are provided: - Future studies designed to describe stormwater plumes should include a combination of ship - and remote sensing-based methods. - CDOM is a good proxy of the freshwater runoff plume and should be added as a standard measurement parameter on water quality instrument packages. - Investigations are needed that assess on a local basis the spatial extent of ecological effects of stormwater plumes early in the storm, ideally accompanied by airborne imagery to provide improved temporal & spatial resolution, to fill in knowledge gaps. The next Bight regional monitoring program should focus on quantifying nutrient loadings and dynamics in association with stormwater runoff and other sources, and characterize their attendant ecosystem impacts such as phytoplankton blooms.

The 2014/15 Warm Anomaly in the Southern California Current - Physical and Biological Responses

NASA Astrophysics Data System (ADS)

Ralf, G.

2016-02-01

The 2014/15 Warm Anomaly (WarmA) off Southern California manifested itself in the summer of 2014 as an anomalously warm surface layer in the Southern Calif. Bight with low concentrations of Chl a. This layer intensified in spatial extent, covering the entire CalCOFI surface area by the winter of 2015 with temperature anomalies 3 StDev larger than long-term averages. Concentrations of nutrients, phytoplankton biomass and rates of primary production were extremely low during the WarmA. The evolution of the WarmA as well as the 2015/16 El Niño with time will be compared to the evolution of the weak and strong El Niño's observed over the last 60 years. These events provide unique insights in the controls of phytoplankton biomass and production in the southern California Current System. Preliminary analyses suggest that the response of the phytoplankton community to the WarmA was consistent with responses to similar forcing during the prior decade. This presentation is based on data collected during the quarterly CalCOFI cruises by the CalCOFI and the CCE-LTER groups.

Effects of fire and emergency seeding on hillslope erosion in southern California chaparral

Treesearch

Pete Wohlgemuth; Jan Beyers; C.D. Wakeman; S.G. Conard

2002-01-01

Catastrophic wildfires can set the stage for massive postfire erosion and sedimentation in southern California chaparral ecosystems with the onset of heavy winter rainstorms. As a mitigation measure, land managers have typically used grass seeding as a standard emergency rehabilitation technique. However, the effectiveness of grass seeding as a watershed protection...

75 FR 4344 - Foreign-Trade Zone 50-Long Beach, California Application for Subzone Allegro Mfg. Inc. (Cosmetic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-27

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket 6-2010] Foreign-Trade Zone 50--Long Beach, California Application for Subzone Allegro Mfg. Inc. (Cosmetic, Organizer and Electronic Bags and Accessories) Commerce, CA An application has been submitted to the Foreign-Trade Zones Board (the Board) by the Port of...

Potential impacts of global warming on water resources in southern California.

PubMed

Beuhler, M

2003-01-01

Global warming will have a significant impact on water resources within the 20 to 90-year planning period of many water projects. Arid and semi-arid regions such as Southern California are especially vulnerable to anticipated negative impacts of global warming on water resources. Long-range water facility planning must consider global climate change in the recommended mix of new facilities needed to meet future water requirements. The generally accepted impacts of global warming include temperature, rising sea levels, more frequent and severe floods and droughts, and a shift from snowfall to rain. Precipitation changes are more difficult to predict. For Southern California, these impacts will be especially severe on surface water supplies. Additionally, rising sea levels will exacerbate salt-water intrusion into freshwater and impact the quality of surface water supplies. Integrated water resources planning is emerging as a tool to develop water supplies and demand management strategies that are less vulnerable to the impacts of global warming. These tools include water conservation, conjunctive use of surface and groundwater and desalination of brackish water and possibly seawater. Additionally, planning for future water needs should include explicit consideration of the potential range of global warming impacts through techniques such as scenario planning.

Regional Assessment of Human Fecal Contamination in Southern California Coastal Drainages

PubMed Central

Cao, Yiping; Raith, Meredith R.; Smith, Paul D.; Griffith, John F.; Weisberg, Stephen B.; Schriewer, Alexander; Sheldon, Andrew; Crompton, Chris; Gregory, Jason; Guzman, Joe; Othman, Laila; Manasjan, Mayela; Choi, Samuel; Rapoport, Shana; Steele, Syreeta; Nguyen, Tommy; Yu, Xueyuan

2017-01-01

Host-associated genetic markers that allow for fecal source identification have been used extensively as a diagnostic tool to determine fecal sources within watersheds, but have not been used in routine monitoring to prioritize remediation actions among watersheds. Here, we present a regional assessment of human marker prevalence among drainages that discharge to the U.S. southern California coast. Approximately 50 samples were analyzed for the HF183 human marker from each of 22 southern California coastal drainages under summer dry weather conditions, and another 50 samples were targeted from each of 23 drainages during wet weather. The HF183 marker was ubiquitous, detected in all but two sites in dry weather and at all sites during wet weather. However, there was considerable difference in the extent of human fecal contamination among sites. Similar site ranking was produced regardless of whether the assessment was based on frequency of HF183 detection or site average HF183 concentration. However, site ranking differed greatly between dry and wet weather. Site ranking also differed greatly when based on enterococci, which do not distinguish between pollution sources, vs. HF183, which distinguishes higher risk human fecal sources from other sources, indicating the additional value of the human-associated marker as a routine monitoring tool. PMID:28777324

Regional Assessment of Human Fecal Contamination in Southern California Coastal Drainages.

PubMed

Cao, Yiping; Raith, Meredith R; Smith, Paul D; Griffith, John F; Weisberg, Stephen B; Schriewer, Alexander; Sheldon, Andrew; Crompton, Chris; Amenu, Geremew G; Gregory, Jason; Guzman, Joe; Goodwin, Kelly D; Othman, Laila; Manasjan, Mayela; Choi, Samuel; Rapoport, Shana; Steele, Syreeta; Nguyen, Tommy; Yu, Xueyuan

2017-08-04

Host-associated genetic markers that allow for fecal source identification have been used extensively as a diagnostic tool to determine fecal sources within watersheds, but have not been used in routine monitoring to prioritize remediation actions among watersheds. Here, we present a regional assessment of human marker prevalence among drainages that discharge to the U.S. southern California coast. Approximately 50 samples were analyzed for the HF183 human marker from each of 22 southern California coastal drainages under summer dry weather conditions, and another 50 samples were targeted from each of 23 drainages during wet weather. The HF183 marker was ubiquitous, detected in all but two sites in dry weather and at all sites during wet weather. However, there was considerable difference in the extent of human fecal contamination among sites. Similar site ranking was produced regardless of whether the assessment was based on frequency of HF183 detection or site average HF183 concentration. However, site ranking differed greatly between dry and wet weather. Site ranking also differed greatly when based on enterococci, which do not distinguish between pollution sources, vs. HF183, which distinguishes higher risk human fecal sources from other sources, indicating the additional value of the human-associated marker as a routine monitoring tool.

Visitor perceptions of crowding and discrimination at two National Forests in southern California

Treesearch

Deborah J. Chavez

1993-01-01

Visitors to southern California National Forests are urban dwellers and as a group are culturally diverse. To manage the National Forests for this diverse group of visitors, information is needed on their expectations, preferences, and experiences at recreation sites. To evaluate visitor perceptions of crowding and discrimination, to determine favorite activities, and...

Timber resource statistics for the San Joaquin and southern resource areas of California.

Treesearch

Karen L. Waddell; Patricia M. Bassett

1997-01-01

This report is a summary of timber resource statistics for the San Joaquin and Southern Resource Areas of California, which include Alpine, Amador, Calaveras, Fresno, Imperial, Inyo, Kern, Kings, Los Angeles, Madera, Mariposa, Merced, Mono, Orange, Riverside, San Bernardino, San Diego, San Joaquin, Stanislaus, Tulare, and Tuolumne Counties. Data were collected as part...

50 CFR Table 6 to Part 226 - Hydrologic Units and Counties Containing Critical Habitat for Southern Oregon/Northern California...

Code of Federal Regulations, 2010 CFR

2010-10-01

... Critical Habitat for Southern Oregon/Northern California Coasts Coho Salmon, Tribal Lands Within the Range... California Coasts Coho Salmon, Tribal Lands Within the Range of the ESU, and Dams/Reservoirs Representing the... (CA), Trinity (CA)—Hoopa Valley Reservation Lewiston Dam (Lewiston Reservoir). Salmon 18010210...

50 CFR Table 6 to Part 226 - Hydrologic Units and Counties Containing Critical Habitat for Southern Oregon/Northern California...

Code of Federal Regulations, 2011 CFR

2011-10-01

... Critical Habitat for Southern Oregon/Northern California Coasts Coho Salmon, Tribal Lands Within the Range... California Coasts Coho Salmon, Tribal Lands Within the Range of the ESU, and Dams/Reservoirs Representing the... (CA), Trinity (CA)—Hoopa Valley Reservation Lewiston Dam (Lewiston Reservoir). Salmon 18010210...

Estimating Earthquake Hazards in the San Pedro Shelf Region, Southern California

NASA Astrophysics Data System (ADS)

Baher, S.; Fuis, G.; Normark, W. R.; Sliter, R.

2003-12-01

The San Pedro Shelf (SPS) region of the inner California Borderland offshore southern California poses a significant seismic hazard to the contiguous Los Angeles Area, as a consequence of late Cenozoic compressional reactivation of mid-Cenozoic extensional faults. The extent of the hazard, however, is poorly understood because of the complexity of fault geometries and uncertainties in earthquake locations. The major faults in the region include the Palos Verdes, THUMS Huntington Beach and the Newport-Inglewood fault zones. We report here the analysis and interpretation of wide-angle seismic-reflection and refraction data recorded as part of the Los Angeles Region Seismic Experiment line 1 (LARSE 1), multichannel seismic (MCS) reflection data obtained by the USGS (1998-2000) and industry borehole stratigraphy. The onshore-offshore velocity model, which is based on forward modeling of the refracted P-wave arrival times, is used to depth migrate the LARSE 1 section. Borehole stratigraphy allows correlation of the onshore and offshore velocity models because state regulations prevent collection of deep-penetration acoustic data nearshore (within 3 mi.). Our refraction study is an extension of ten Brink et al., 2000 tomographic inversion of LARSE I data. They found high velocities (> 6 km/sec) at about ~3.5 km depth from the Catalina Fault (CF) to the SPS. We find these velocities, shallower (around 2 km depth) beneath the Catalina Ridge (CR) and SPS, but at a depth 2.5-3.0 km elsewhere in the study region. This change in velocity structure can provide additional constraints for the tectonic processes of this region. The structural horizons observed in the LARSE 1 reflection data are tied to adjacent MCS lines. We find localized folding and faulting at depth (~2 km) southwest of the CR and on the SPS slope. Quasi-laminar beds, possible of pelagic origin follow the contours of earlier folded (wavelength ~1 km) and faulted Cenozoic sedimentary and volcanic rocks. Depth to

Recent deformation on the San Diego Trough and San Pedro Basin fault systems, offshore Southern California: Assessing evidence for fault system connectivity.

NASA Astrophysics Data System (ADS)

Bormann, J. M.; Kent, G. M.; Driscoll, N. W.; Harding, A. J.

2016-12-01

The seismic hazard posed by offshore faults for coastal communities in Southern California is poorly understood and may be considerable, especially when these communities are located near long faults that have the ability to produce large earthquakes. The San Diego Trough fault (SDTF) and San Pedro Basin fault (SPBF) systems are active northwest striking, right-lateral faults in the Inner California Borderland that extend offshore between San Diego and Los Angeles. Recent work shows that the SDTF slip rate accounts for 25% of the 6-8 mm/yr of deformation accommodated by the offshore fault network, and seismic reflection data suggest that these two fault zones may be one continuous structure. Here, we use recently acquired CHIRP, high-resolution multichannel seismic (MCS) reflection, and multibeam bathymetric data in combination with USGS and industry MCS profiles to characterize recent deformation on the SDTF and SPBF zones and to evaluate the potential for an end-to-end rupture that spans both fault systems. The SDTF offsets young sediments at the seafloor for 130 km between the US/Mexico border and Avalon Knoll. The northern SPBF has robust geomorphic expression and offsets the seafloor in the Santa Monica Basin. The southern SPBF lies within a 25-km gap between high-resolution MCS surveys. Although there does appear to be a through-going fault at depth in industry MCS profiles, the low vertical resolution of these data inhibits our ability to confirm recent slip on the southern SPBF. Empirical scaling relationships indicate that a 200-km-long rupture of the SDTF and its southern extension, the Bahia Soledad fault, could produce a M7.7 earthquake. If the SDTF and the SPBF are linked, the length of the combined fault increases to >270 km. This may allow ruptures initiating on the SDTF to propagate within 25 km of the Los Angeles Basin. At present, the paleoseismic histories of the faults are unknown. We present new observations from CHIRP and coring surveys at

Habitat fragmentation in coastal southern California disrupts genetic connectivity in the cactus wren (Campylorhynchus brunneicapillus).

PubMed

Barr, Kelly R; Kus, Barbara E; Preston, Kristine L; Howell, Scarlett; Perkins, Emily; Vandergast, Amy G

2015-05-01

Achieving long-term persistence of species in urbanized landscapes requires characterizing population genetic structure to understand and manage the effects of anthropogenic disturbance on connectivity. Urbanization over the past century in coastal southern California has caused both precipitous loss of coastal sage scrub habitat and declines in populations of the cactus wren (Campylorhynchus brunneicapillus). Using 22 microsatellite loci, we found that remnant cactus wren aggregations in coastal southern California comprised 20 populations based on strict exact tests for population differentiation, and 12 genetic clusters with hierarchical Bayesian clustering analyses. Genetic structure patterns largely mirrored underlying habitat availability, with cluster and population boundaries coinciding with fragmentation caused primarily by urbanization. Using a habitat model we developed, we detected stronger associations between habitat-based distances and genetic distances than Euclidean geographic distance. Within populations, we detected a positive association between available local habitat and allelic richness and a negative association with relatedness. Isolation-by-distance patterns varied over the study area, which we attribute to temporal differences in anthropogenic landscape development. We also found that genetic bottleneck signals were associated with wildfire frequency. These results indicate that habitat fragmentation and alterations have reduced genetic connectivity and diversity of cactus wren populations in coastal southern California. Management efforts focused on improving connectivity among remaining populations may help to ensure population persistence. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

76 FR 37649 - Safety Zone; Northern California Annual Fireworks Events, July 4th Fireworks Display

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... Zone; Northern California Annual Fireworks Events, July 4th Fireworks Display AGENCY: Coast Guard, DHS... annual July 4th Fireworks Display (Tahoe City 4th of July Fireworks Display). This action is necessary to... INFORMATION: The Coast Guard will enforce the safety zone for the annual Tahoe City 4th of July Fireworks in...

Near-surface tomography of southern California from noise cross-correlation H/V measurements

NASA Astrophysics Data System (ADS)

Muir, J. B.; Tsai, V. C.

2016-12-01

The development of noise cross-correlation techniques constitutes one of the major advances in observational seismology in the past 15 years. The first data derived from noise cross correlations were surface wave phase velocities, but as the technique matures many more observables of noise cross-correlations are being used in seismic studies. One such observable is the horizontal-to-vertical amplitude ratio (H/V) of noise cross-correlations. We interpret the H/V ratio of noise cross correlations in terms of Rayleigh wave ellipticity. We have inverted the H/V of Rayleigh waves observed in noise cross-correlation signals to develop a 3D tomogram of Southern California. This technique has recently been employed (e.g. Lin et al. 2014) on a continental scale, using data from the Transportable Array in the period range of 8-24s. The finer inter-station spacing of the SCSN allows retrieval of high signal-to-noise ratio Rayleigh waves at a period of as low as 2s, significantly improving the vertical resolution of the resulting tomography. In addition, horizontal resolution is naturally improved by increased station density. This study constitutes a useful addition to traditional phase-velocity based tomographic inversions due to the localized sensitivity of H/V measurements to the near surface of the measurement station site. The continuous data of 222 permanent broadband stations of the Southern California Seismic Network (SCSN) were used in production of noise cross-correlation waveforms, resulting in a spatially dense set of measurements for the Southern California region in the 2-15s period band. Tectonic sub-regions including the LA Basin and Salton Trough are clearly visible due to their high short-period H/V ratios, whilst the Transverse and Peninsular ranges exhibit low H/V at all periods.

Forecast skill of synoptic conditions associated with Santa Ana winds in Southern California

Treesearch

Charles Jones; Francis Fujioka; Leila M.V. Carvalho

2010-01-01

Santa Ana winds (SAW) are synoptically driven mesoscale winds observed in Southern California usually during late fall and winter. Because of the complex topography of the region, SAW episodes can sometimes be extremely intense and pose significant environmental hazards, especially during wildfire incidents. A simple set of criteria was used to identify synoptic-scale...

Valuing morbidity effects of wildfire smoke exposure from the 2007 Southern California wildfires

Treesearch

Ikuho Kochi; Patricia A. Champ; John B. Loomis; Geoffrey H. Donovan

2016-01-01

This study estimated the economic costs associated with morbidity from the wildfires that occurred in 2007 in southern California. We used the excess number of hospital admissions and emergency department visits to quantify the morbidity effects and used medical costs to estimate the economic impact. With data from 187 hospital facilities and 140 emergency departments...

76 FR 41237 - Metropolitan Water District of Southern California; Notice of Effectiveness of Surrender

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-13

... Water District of Southern California; Notice of Effectiveness of Surrender On September 17, 2001, the Commission issued an Order Granting Exemption from Licensing (Conduit) \\1\\ to the Metropolitan Water District... Connection, which transfers water from the Allen-McCulloch Pipeline to the South County Pipeline. \\1...

Permit application and approval chronology for a small airgun survey offshore southern California, June 1999

USGS Publications Warehouse

Childs, Jonathan R.; Normark, William R.; Fisher, Michael A.

1999-01-01

Offshore geophysical surveys are subject to increased restrictions resulting from new or revised Federal legislation and increased authority of State agencies that deal with environmental issues. This report reviews the process followed by the U.S. Geological Survey to obtain necessary approvals for a marine geophysical survey conducted in June, 1999, offshore Southern California. Discussions and negotiations between the USGS, National Marine Fisheries Service, the California Coastal Commission, the California State Lands Commission, and various other interested parties during six months prior to the survey are documented. A suggested timeframe that should be followed for obtaining the approvals and permits for future work offshore California is based on the outcome of the permitting process for the 1999 cruise, as well as continuing dialog with representatives of the Federal and State entities involved.

The availability of local aerial photography in southern California. [for solution of urban planning problems

NASA Technical Reports Server (NTRS)

Allen, W., III; Sledge, B.; Paul, C. K.; Landini, A. J.

1974-01-01

Some of the major photography and photogrammetric suppliers and users located in Southern California are listed. Recent trends in aerial photographic coverage of the Los Angeles basin area are also noted, as well as the uses of that imagery.

Late Quaternary Faulting along the San Juan de los Planes Fault Zone, Baja California Sur, Mexico

NASA Astrophysics Data System (ADS)

Busch, M. M.; Coyan, J. A.; Arrowsmith, J.; Maloney, S. J.; Gutierrez, G.; Umhoefer, P. J.

2007-12-01

As a result of continued distributed deformation in the Gulf Extensional Province along an oblique-divergent plate margin, active normal faulting is well manifest in southeastern Baja California. By characterizing normal-fault related deformation along the San Juan de los Planes fault zone (SJPFZ) southwest of La Paz, Baja California Sur we contribute to understanding the patterns and rates of faulting along the southwest gulf-margin fault system. The geometry, history, and rate of faulting provide constraints on the relative significance of gulf-margin deformation as compared to axial system deformation. The SJPFZ is a major north-trending structure in the southern Baja margin along which we focused our field efforts. These investigations included: a detailed strip map of the active fault zone, including delineation of active scarp traces and geomorphic surfaces on the hanging wall and footwall; fault scarp profiles; analysis of bedrock structures to better understand how the pattern and rate of strain varied during the development of this fault zone; and a gravity survey across the San Juan de los Planes basin to determine basin geometry and fault behavior. The map covers a N-S swath from the Gulf of California in the north to San Antonio in the south, an area ~45km long and ~1-4km wide. Bedrock along the SJPFZ varies from Cretaceous Las Cruces Granite in the north to Cretaceous Buena Mujer Tonalite in the south and is scarred by shear zones and brittle faults. The active scarp-forming fault juxtaposes bedrock in the footwall against Late Quaternary sandstone-conglomerate. This ~20m wide zone is highly fractured bedrock infused with carbonate. The northern ~12km of the SJPFZ, trending 200°, preserves discontinuous scarps 1-2km long and 1-3m high in Quaternary units. The scarps are separated by stretches of bedrock embayed by hundreds of meters-wide tongues of Quaternary sandstone-conglomerate, implying low Quaternary slip rate. Further south, ~2 km north of the

The influence of Pacific Equatorial Water on fish diversity in the southern California Current System

NASA Astrophysics Data System (ADS)

McClatchie, Sam; Thompson, Andrew R.; Alin, Simone R.; Siedlecki, Samantha; Watson, William; Bograd, Steven J.

2016-08-01

The California Undercurrent transports Pacific Equatorial Water (PEW) into the Southern California Bight from the eastern tropical Pacific Ocean. PEW is characterized by higher temperatures and salinities, with lower pH, representing a source of potentially corrosive (aragonite,Ω<1) water to the region. We use ichthyoplankton assemblages near the cores of the California Current and the California Undercurrent to determine whether PEW influenced fish diversity. We use hydrographic data to characterize the interannual and seasonal variability of estimated pH and aragonite saturation with depth. Although there is substantial variability in PEW presence as measured by spice on the 26.25-26.75 isopycnal layer, as well as in pH and aragonite saturation, we found fish diversity to be stable over the decades 1985-1996 and 1999-2011. We detected significant difference in species structure during the 1998 La Niña period, due to reduced species evenness. Species richness due to rare species was higher during the 1997/1998 El Niño compared to the La Niña but the effect on species structure was undetectable. Lack of difference in the species abundance structure in the decade before and after the 1997/1999 ENSO event showed that the assemblage reverted to its former structure following the ENSO perturbation, indicating resilience. While the interdecadal species structure remained stable, the long tail of the distributions shows that species richness increased between the decades consistent with intrusion of warm water with more diverse assemblages into the southern California region.

Polymorphic site index curves for red fir in California and southern Oregon

Treesearch

K. Leroy Dolph

1991-01-01

Polymorphic site index curves were developed from stem analysis data of 194 dominant red fir trees in California and southern Oregon. Site index was based on breast-height age and total tree height, with a base age of 50 years at breast height. Site index curves for breast height ages 10 to 160 years are presented for approximate estimates of site index. For more...

California State Waters Map Series: offshore of San Gregorio, California

USGS Publications Warehouse

Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Watt, Janet T.; Golden, Nadine E.; Endris, Charles A.; Phillips, Eleyne L.; Hartwell, Stephen R.; Johnson, Samuel Y.; Kvitek, Rikk G.; Erdey, Mercedes D.; Bretz, Carrie K.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Dieter, Bryan E.; Chin, John L.; Cochran, Susan A.; Cochrane, Guy R.; Cochran, Susan A.

2014-01-01

the northern and southern parts of the map area are the result of right-lateral motion on strands of the San Gregorio Fault system. In the south, headlands near Pescadero Point have been uplifted by motion along the west strand of the San Gregorio Fault (also called the Frijoles Fault), which separates rocks of the Pigeon Point Formation south of the fault from rocks of the Purisima Formation north of the fault. The regional uplift in this map area has caused relatively shallow water depths within California's State Waters and, thus, little accommodation space for sediment accumulation. Sediment is observed offshore in the central part of the map area, in the shelter of the headlands north of the east strand of the San Gregorio Fault (also called the Coastways Fault) around Miramontes Point (about 5 km north of the map area) and also on the outer half of the California's State Waters shelf in the south where depths exceed 40 m. Sediment in the outer shelf of California's State Waters is rippled, indicating some mobility. The Offshore of San Gregorio map area lies within the cold-temperate biogeographic zone that is called either the "Oregonian province" or the "northern California ecoregion." This biogeographic province is maintained by the long-term stability of the southward-flowing California Current, an eastern limb of the North Pacific subtropical gyre that flows from Oregon to Baja California. At its midpoint off central California, the California Current transports subarctic surface (0–500 m deep) waters southward, about 150 to 1,300 km from shore. Seasonal northwesterly winds that are, in part, responsible for the California Current, generate coastal upwelling. The south end of the Oregonian province is at Point Conception (about 350 km south of the map area), although its associated phylogeographic group of marine fauna may extend beyond to the area offshore of Los Angeles in southern California. The ocean off of central California has experienced a warming

Wildfires alter rodent community structure across four vegetation types in southern California, USA

USGS Publications Warehouse

Brehme, Cheryl S.; Clark, Denise R.; Rochester, Carlton J.; Fisher, Robert N.

2011-01-01

We surveyed burned and unburned plots across four habitat reserves in San Diego County, California, USA, in 2005 and 2006, to assess the effects of the 2003 wildfires on the community structure and relative abundance of rodent species. The reserves each contained multiple vegetation types (coastal sage scrub, chaparral, woodland, and grassland) and spanned from 250 m to 1078 m in elevation. Multivariate analyses revealed a more simplified rodent community structure in all burned habitats in comparison to unburned habitats. Reduction in shrub and tree cover was highly predictive of changes in post-fire rodent community structure in the burned coastal sage scrub and chaparral habitats. Reduction in cover was not predictive for the less substantially burned woodlands and grasslands, for which we hypothesized that interspecific competition played a greater role in post-fire community structure. Across vegetation types, generalists and open habitat specialists typically increased in relative abundance, whereas closed habitat specialists decreased. We documented significant increases in relative abundance of the deer mouse (Peromyscus maniculatus Wagner) and Dulzura kangaroo rat (Dipodomys simulans Merriam). In contrast, we found significant decreases in relative abundance for the California mouse (Peromyscus californicus Gambel), San Diego pocket mouse (Chaetodipus fallax Merriam), desert woodrat (Neotoma lepida Thomas), and brush mouse (Peromyscus boylii Baird). Currently, our research program involves assessment of whether habitat conservation plans (HCPs) in southern California provide long-term protection to HCP covered species, as well as preserve ecosystem function. The scenario of increased wildfires needs to be incorporated into this assessment. We discuss our results in relation to management and conservation planning under a future scenario of larger and more frequent wildfires in southern California.

75 FR 35649 - Safety Zone; Northern California Annual Fireworks Events, July 4th Fireworks Display

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-23

... Zone; Northern California Annual Fireworks Events, July 4th Fireworks Display AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the Tahoe City 4th of... safety zone for the annual Tahoe City 4th of July Fireworks in 33 CFR 165.1191 on July 4, 2010, from 9 a...

Vector-Host Interactions Governing Epidemiology of West Nile Virus in Southern California

PubMed Central

Molaei, Goudarz; Cummings, Robert F.; Su, Tianyun; Armstrong, Philip M.; Williams, Greg A.; Cheng, Min-Lee; Webb, James P.; Andreadis, Theodore G.

2010-01-01

Southern California remains an important focus of West Nile virus (WNV) activity, with persistently elevated incidence after invasion by the virus in 2003 and subsequent amplification to epidemic levels in 2004. Eco-epidemiological studies of vectors-hosts-pathogen interactions are of paramount importance for better understanding of the transmission dynamics of WNV and other emerging mosquito-borne arboviruses. We investigated vector-host interactions and host-feeding patterns of 531 blood-engorged mosquitoes in four competent mosquito vectors by using a polymerase chain reaction (PCR) method targeting mitochondrial DNA to identify vertebrate hosts of blood-fed mosquitoes. Diagnostic testing by cell culture, real-time reverse transcriptase-PCR, and immunoassays were used to examine WNV infection in blood-fed mosquitoes, mosquito pools, dead birds, and mammals. Prevalence of WNV antibodies among wild birds was estimated by using a blocking enzyme-linked immunosorbent assay. Analyses of engorged Culex quinquefasciatus revealed that this mosquito species acquired 88.4% of the blood meals from avian and 11.6% from mammalian hosts, including humans. Similarly, Culex tarsalis fed 82% on birds and 18% on mammals. Culex erythrothorax fed on both birds (59%) and mammals (41%). In contrast, Culex stigmatosoma acquired all blood meals from avian hosts. House finches and a few other mostly passeriform birds served as the main hosts for the blood-seeking mosquitoes. Evidence of WNV infection was detected in mosquito pools, wild birds, dead birds, and mammals, including human fatalities during the study period. Our results emphasize the important role of house finches and several other passeriform birds in the maintenance and amplification of WNV in southern California, with Cx. quinquefasciatus acting as both the principal enzootic and “bridge vector” responsible for the spillover of WNV to humans. Other mosquito species, such as Cx. tarsalis and Cx. stigmatosoma, are

Paleomagnetic Quantification of Neogene Block Rotations within an Active Transtensional Plate Boundary, Baja California, Mexico

NASA Astrophysics Data System (ADS)

Weber, J.; Umhoefer, P. J.; Pérez Venzor, J. A.; Bachtadse, V.

2009-12-01

Compared to oceanic plate boundaries which are generally narrow zones of deformation, continental plate boundaries appear as widespread areas with complex and poorly understood kinematics. Motion of crustal blocks within these “diffuse plate boundaries” causes rather small-scale lithospheric deformation within the boundary zone, while the main plates behave more rigid. Complex deformation patterns of interacting terranes separated by a variety of active faults are the consequence. To study the dynamic implications of boundary zone deformation, the southern part of the Baja California peninsula, Mexico (Baja) has been chosen as target for a detailed paleomagnetic study. In combination with geodetic measurements it is tried to characterize rigid block rotations and temporal changes in rotation rates. Up to now, little paleomagnetic work directed toward vertical axis rotations has been done in Baja California, despite its location in a major active transtensional zone. To address this problem, a total of 501 cores from 63 sites in the southern part of Baja - including sites on San José Island, San Francisco Island and Cerralvo Island - has been taken from volcanic and sedimentary rocks covering the last 25 million years in time. The analysis of paleomagnetic declinations and comparison to coeval data from North America and stable areas of Baja California allow evaluating the long-term kinematics of the region and the effects of oblique-rifting in the Gulf of California to the east. Nearly all sampled sites indicate vertical axis rotation up to 30-40 degrees with an average of about 20-25 degrees. Depending on the location these rotations have been either clockwise or counter-clockwise and are correlated with the opening of the Gulf of California and the translation of the Baja California peninsula to the North. Results of the paleomagnetic investigation are compared to geodetic data of the last few years in order to address the problem how strain is partitioned

Forecasting sea cliff retreat in Southern California using process-based models and artificial neural networks

NASA Astrophysics Data System (ADS)

Limber, P. W.; Barnard, P.; Erikson, L. H.

2016-02-01

Modeling coastal geomorphic change over multi-decadal time and regional spatial scales (i.e. >20 km alongshore) is in high demand due to rising global sea levels and heavily populated coastal zones, but is challenging for several reasons: adequate geomorphic and oceanographic data often does not exist over the entire study area or time period; models can be too computationally expensive; and model uncertainty is high. In the absence of rich datasets and unlimited computer processing power, researchers are forced to leverage existing data, however sparse, and find analytical methods that minimize computation time without sacrificing (too much) model reliability. Machine learning techniques, such as artificial neural networks, can assimilate and efficiently extrapolate geomorphic model behavior over large areas. They can also facilitate ensemble model forecasts over a broad range of parameter space, which is useful when a paucity of observational data inhibits the constraint of model parameters. Here, we assimilate the behavior of two established process-based sea cliff erosion and retreat models into a neural network to forecast the impacts of sea level rise on sea cliff retreat in Southern California ( 400 km) through the 21st century. Using inputs such as historical cliff retreat rates, mean wave power, and whether or not a beach is present, the neural network independently reproduces modeled sea cliff retreat as a function of sea level rise with a high degree of confidence (R2 > 0.9, mean squared error < 0.1 m yr-1). Results will continuously improve as more model scenarios are assimilated into the neural network, and more field data (i.e., cliff composition and rock hardness) becomes available to tune the cliff retreat models. Preliminary results suggest that sea level rise rates of 2 to 20 mm yr-1 during the next century could accelerate historical cliff retreat rates in Southern California by an average of 0.10 - 0.56 m yr-1.

76 FR 37650 - Safety Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, South Lake...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, South Lake Tahoe Gaming... will enforce the safety zone for the annual Fourth of July Fireworks, South Lake Tahoe Gaming Alliance (Lights on the Lake Fireworks Display). This action is necessary to control vessel traffic and to ensure...

Predicting height increment of young-growth red fir in California and southern Oregon

Treesearch

K. Leroy Dolph

1992-01-01

An equation is given to estimate 10-year height increment for young-growth red fir trees in California and southern Oregon. The independent variables are the individual tree, stand, and site characteristics significantly related to a tree's height growth. Data used to develop the equation came from stem analysis of 492 trees sampled from 56 stands in the study...

Summar throughfall and winter deposition in the San Bernardino mountains in southern California

Treesearch

Mark E. Fenn; Andrzej Bytnerowicz

1997-01-01

Summer throughfall and year-round precipitation chemistry were studied for three years at Barton Flats (BF), a low to moderate pollution site in the San Bernardino Mountains (SBM) in southern California. Winter fog plus dry deposition, and bulk deposition were also measured during one season at three sites traversing an atmospheric deposition gradient in the SBM....

Summer throughfall and winter deposition in the San Bernardino mountains in southern California

Treesearch

M. E. Fenn; A. Bytnerowicz

1997-01-01

Summer throughfall and year-round precipitation chemistry were studied for three years at Barton Flats (BF), a low to moderate pollution site in the San Bernardino Mountains (SBM) in southern California. Winter fog plus dry deposition, and bulk deposition were also measured during one season at three sites traversing an atmospheric deposition gradient in the SBM....

Effect high intensity storms on soil slippage on mountainous watersheds in Southern California

Treesearch

R. M. Rice; G. T. Foggin

1971-01-01

The conversion of brush areas to grassland increased soil slip erosion on mountainous watersheds in southern California during the intense winter storms of 1969. The incidence of soil slippage, site factors affecting slope stability, and amount of debris generated by slippage were investigated for sample brush and grass areas in the San Dimas Experimental Forest. Soil...

Agrilus auroguttatus (Coleoptera: Buprestidae) seasonal development within Quercus agrifolia (Fagales: Fagaceae) in southern California

Treesearch

L.J. Haavik; T.W. Coleman; M.L. Flint; R.C. Venette; S.J. Seybold

2013-01-01

We investigated seasonal development of the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), and physical conditions of the phloem within a preferred host species, coast live oak, Quercus agrifolia Née. We sampled infested trees on a monthly basis at two sites in southern California throughout...

Evolution of Late Miocene to Contemporary Displacement Transfer Between the Northern Furnace Creek and Southern Fish Lake Valley Fault Zones and the Central Walker Lane, Western Great Basin, Nevada

NASA Astrophysics Data System (ADS)

Oldow, J. S.; Geissman, J. W.

2013-12-01

Late Miocene to contemporary displacement transfer from the north Furnace Creek (FCF) and southern Fish Lake Valley (FLVF) faults to structures in the central Walker Lane was and continues to be accommodated by a belt of WNW-striking left-oblique fault zones in the northern part of the southern Walker Lane. The WNW fault zones are 2-9 km wide belts of anastomosing fault strands that intersect the NNW-striking FCF and southern FLVF in northern Death Valley and southern Fish Lake Valley, respectively. The WNW fault zones extend east for over 60 km where they merge with a 5-10 km wide belt of N10W striking faults that marks the eastern boundary of the southern Walker Lane. Left-oblique displacement on WNW faults progressively decreases to the east, as motion is successively transferred northeast on NNE-striking faults. NNE faults localize and internally deform extensional basins that each record cumulative net vertical displacements of between 3.0 and 5.2 km. The transcurrent faults and associated basins decrease in age from south to north. In the south, the WNW Sylvania Mountain fault system initiated left-oblique motion after 7 Ma but does not have evidence of contemporary displacement. Farther north, the left-oblique motion on the Palmetto Mountain fault system initiated after 6.0 to 4.0 Ma and has well-developed scarps in Quaternary deposits. Cumulative left-lateral displacement for the Sylvania Mountain fault system is 10-15 km, and is 8-12 km for the Palmetto fault system. The NNE-striking faults that emanate from the left-oblique faults merge with NNW transcurrent faults farther north in the eastern part of the Mina deflection, which links the Owens Valley fault of eastern California to the central Walker Lane. Left-oblique displacement on the Sylvania Mountain and Palmetto Mountain fault zones deformed the Furnace Creek and Fish Lake Valley faults. Left-oblique motion on Sylvania Mountain fault deflected the FCF into the 15 km wide Cucomungo Canyon restraining

Annual Conference of Southern California and Arizona Community College Superintendents and Presidents (Lake Arrowhead Conference Center, California, October 6-8, 1970).

ERIC Educational Resources Information Center

California Univ., Los Angeles. Junior Coll. Leadership Program.

An address on "Public Confidence in Higher Education" by the chairman of the board of the Bank of America opended the 1970 Lake Arrowhead Conference of Southern California and Arizona community college superintendents and presidents. A summary of this speech and the questions and answers that followed it are included here. Comments from conference…

Sediment Cd and Mo accumulation in the oxygen-minimum zone off western Baja California linked to global climate over the past 52 kyr

USGS Publications Warehouse

Dean, W.E.; Zheng, Yen; Ortiz, J.D.; VanGeen, A.

2006-01-01

Concentrations of organic carbon (orgC), cadmium (Cd), and molybdenum (Mo) were measured in two sediment cores raised from depths of 430 and 700 m within the oxygen-minimum zone (OMZ) off southern Baja California at a temporal resolution of e10.5 kyr over the past 52 kyr. These records are supplemented with diffuse spectral reflectance (DSR) measurements obtained on board ship soon after collection at a resolution of e10.05 kyr. In the core from 700 m depth, a component extracted from the DSR data and the three geochemical proxies generally vary in concert with each other and over a wide range (4-22% orgC; 1-40 mg/kg Cd; 5-120 mg/kg Mo). Intervals of increased orgC, Cd, and Mo accumulation generally correspond to warm periods recorded in the oxygen-isotopic composition of Greenland ice, with the exception of the Bolling/Allerod which is only weakly expressed off Baja California. Concentrations of the biogenic proxies are higher in the core from 430 m depth, but erratic sediment accumulation before 15 ka precludes dating of the older intervals that are laminated and contain elevated orgC, Cd, and Mo concentrations. The new data provide further evidence of an intimate teleconnection between global climate and the intensity of the OMZ and/or productivity along the western margin of North America. On the basis of a comparison with Cd and Mo records collected elsewhere in the region, we conclude that productivity may actually have varied off southern Baja California by no more than a factor of 2 over the past 52 kyr. Copyright 2006 by the American Geophysical Union.

Landscape-level connectivity in coastal southern California, USA, as assessed through carnivore habitat suitability

USGS Publications Warehouse

Hunter, Richard D.; Fisher, Robert N.; Crooks, Kevin R.

2003-01-01

Although the fragmentation of the natural landscape of coastal southern California, USA, is accelerating, large-scale assessments of regional connectivity are lacking. Because of their large area requirements and long dispersal movements, mammalian carnivores can be effective focal species to use when evaluating landscape-level connectivity. Our goal was to make an initial assessment of the extent of landscape-level connectivity in coastal southern California using mountain lions (Felis concolor [Linnaeus]) and bobcats (Felis rufus [Shreber]) as focal species. We first characterized habitat preferences for mountain lions and bobcats from previously derived habitat relationship models for these species; the resulting maps provided a coarse view of habitat preferences for use at regional scales. We then constructed GIS models to evaluate the disturbance impact of roadways and development, major determinants of carnivore distribution and abundance in the south coast region. Finally, we combined the habitat relationship models with the disturbance impact models to characterize habitat connectivity for mountain lions and bobcats in the ecoregion. Habitat connectivity in the ecoregion appeared higher for bobcats than for mountain lions due in part to higher habitat suitability for bobcats in coastal lowland areas. Our models suggest that much of the key carnivore habitat in the coastal southern California is at risk; over 80% of high suitability habitat and over 90% of medium suitability habitat for carnivores is found in the least protected land management classes. Overall, these models allow for (1) identification of core habitat blocks for carnivores and key landscape connections between core areas, (2) evaluation of the level of protection of these areas, and (3) a regional framework within which to develop and coordinate local management and conservation plans.

Adjoint Tomography of the Southern California Crust (Invited) (Invited)

NASA Astrophysics Data System (ADS)

Tape, C.; Liu, Q.; Maggi, A.; Tromp, J.

2009-12-01

We iteratively improve a three-dimensional tomographic model of the southern California crust using numerical simulations of seismic wave propagation based on a spectral-element method (SEM) in combination with an adjoint method. The initial 3D model is provided by the Southern California Earthquake Center. The dataset comprises three-component seismic waveforms (i.e. both body and surface waves), filtered over the period range 2-30 s, from 143 local earthquakes recorded by a network of 203 stations. Time windows for measurements are automatically selected by the FLEXWIN algorithm. The misfit function in the tomographic inversion is based on frequency-dependent multitaper traveltime differences. The gradient of the misfit function and related finite-frequency sensitivity kernels for each earthquake are computed using an adjoint technique. The kernels are combined using a source subspace projection method to compute a model update at each iteration of a gradient-based minimization algorithm. The inversion involved 16 iterations, which required 6800 wavefield simulations and a total of 0.8 million CPU hours. The new crustal model, m16, is described in terms of independent shear (Vs) and bulk-sound (Vb) wavespeed variations. It exhibits strong heterogeneity, including local changes of ±30% with respect to the initial 3D model. The model reveals several features that relate to geologic observations, such as sedimentary basins, exhumed batholiths, and contrasting lithologies across faults. The quality of the new model is validated by quantifying waveform misfits of full-length seismograms from 91 earthquakes that were not used in the tomographic inversion. The new model provides more accurate synthetic seismograms that will benefit seismic hazard assessment.

An online review of plastic surgeons in southern California.

PubMed

Lewis, Priya; Kobayashi, Emily; Gupta, Subhas

2015-05-01

It has become commonplace for patients to access online reviews of physicians when making choices about health care, just as any consumer would in today's computer-dependent world. Previous studies have shown that online reviews of physicians are generally positive. However, 1 negative review has the potential to adversely affect business and reputations. To characterize the online presence of plastic surgeons in Southern California as portrayed by physician rating websites (PRWs). An extensive online database of board-certified plastic surgeons was used to generate a list of surgeons within a 50-mile radius of Pomona, CA. Ratings from the PRWs HealthGrades.com, Vitals.com, and UCompareHealthcare.com were cataloged by number of reviews and ratings. Two hundred sixty-three surgeons were evaluated with the most-represented cities being Beverly Hills (N=47), Los Angeles (N=31), and Newport Beach (N=27). Ninety-seven percent of the surgeons were rated on at least 1 of the 3 PRWs chosen. In general, surgeons were rated highly, with a mean rating of 85%, SD, 14% (P<0.01), with a mean of 11.0 ratings per PRW, SD 10.9 (P<0.01). Total online ratings ranged from 0 to 222 per surgeon. The median number of total reviews was 25 and the mean rating for those surgeons above and below the median were equivocal, at 86% and 85%, respectively (P=0.284). In this study, we found that plastic surgeons in Southern California have an online presence that can be influenced by their patients; they should be aware of this and conscious of their online reputations. Overall, the ratings were high, regardless of the number of reviews.

Characteristics of southern California atmospheric rivers

NASA Astrophysics Data System (ADS)

Harris, Sarah M.; Carvalho, Leila M. V.

2018-05-01

Atmospheric rivers (ARs) are channels of high water vapor flux that transport moisture from low to higher latitudes on synoptic timescales. In areas of topographical variability, ARs may lead to high-intensity precipitation due to orographic forcing. ARs landfalling along North America's west coast are linked to extreme events including those leading to flooding and landslides. In southern California (SCA), proper AR forecasting is important for regional water resources as well as hazard mitigation and as the area's annual precipitation totals occur from relatively few storms per season, any changes to storm frequency and/or intensity may have dramatic consequences. Yet, as most regional AR studies focus on the Pacific Northwest, there is little information about SCA ARs. We develop an algorithm to identify ARs landfalling on North America's west coast between 1979 and 2013 within total precipitable water reanalysis fields. ARs are then categorized according to landfall region. To determine and differentiate the characteristics and spatial distributions of ARs affecting these areas, we examine lag composites of various atmospheric variables for each landfall region. SCA ARs differ from ARs landfalling farther north in the days prior to landfall with the position and amplitude of a trough offshore from the Asian continent and ridge over Alaska, as well as the displacement and eastward extension of the jet core that potentially guides AR moisture southwards. The relationships between AR landfalls and the El Niño/Southern Oscillation (ENSO), the Madden-Julian Oscillation (MJO), and the Pacific/North American Teleconnection Pattern (PNA) are also investigated.

77 FR 65909 - Southern California Edison Company; Establishment of Atomic Safety and Licensing Board

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-31

...] Southern California Edison Company; Establishment of Atomic Safety and Licensing Board Pursuant to... 2.104, 2.105, 2.300, 2.309, 2.313, 2.318, and 2.321, notice is hereby given that an Atomic Safety... following administrative judges: Alex S. Karlin, Chair, Atomic Safety and Licensing Board Panel, U.S...

Toward a More Nuanced Understanding of Intercoupling: Second-Generation Mixed Couples in Southern California

ERIC Educational Resources Information Center

Morgan, Charlie V.

2012-01-01

Distinguishing between interethnic and interracial coupling offers new understandings about family diversity, as well as the assimilation of immigrants and their children. An analysis of the Children of Immigrants Longitudinal Study, a survey (N = 1,480) of the children of Asian and Latin American immigrants who live in Southern California, finds…

Educational Characteristics of Paraprofessionals in Southern California: A Survey of Their Career Ladder Needs.

ERIC Educational Resources Information Center

Ochoa, Alberto M.; Wright, Pamela G.

The purpose of this study was to identify the career ladder needs of paraprofessionals as required by both California State and Federal educational mandates. Findings, gathered by questionnaires returned by 594 aides in seven southern and central Californian counties, are discussed in terms of the following: (1) personal characteristics; (2)…

Unusual infections due to Listeria monocytogenes in the Southern California Desert.

PubMed

Cone, Lawrence A; Somero, Michael S; Qureshi, Farsana J; Kerkar, Shuba; Byrd, Richard G; Hirschberg, Joel M; Gauto, Anibal R

2008-11-01

During the past 22 years, 14 patients have been hospitalized with infection due to Listeria monocytogenes at the Eisenhower Medical Center, a regional 300-bed hospital in the desert southwest of Southern California. A large number of patients are retired, elderly, and have underlying and often systemic disease. Blood agar and routine media were inoculated with liquid from a sterile site such as blood, cerebrospinal fluid, or joint fluid and observed daily for growth. Appropriate biochemical studies were used to speciate the organism. While bacteremia and meningitis constitute 75% of infections in most studies, they made up only 36% of patients in the current study. Listeriosis occurred mostly in patients with infected aortic aneurysms and brain abscesses, and in prosthetic joint infections. While mortality is generally stated to be around 45% in patients with listeriosis, it was 35% in this study. However, there were no deaths in five patients with bacteremia or meningitis inferring that organ involvement poses a greater hazard for survival. Listeriosis usually presents as a bacteremia or meningitis due to a food-borne invasive infection. In the desert of Southern California most cases are seen in older patients with underlying disease and present with infected aortic aneurysms, prosthetic joints, and brain abscesses. They represent a greater threat to survival due to organ involvement.

The energy and emissions footprint of water supply for Southern California

NASA Astrophysics Data System (ADS)

Fang, A. J.; Newell, Joshua P.; Cousins, Joshua J.

2015-11-01

Due to climate change and ongoing drought, California and much of the American West face critical water supply challenges. California’s water supply infrastructure sprawls for thousands of miles, from the Colorado River to the Sacramento Delta. Bringing water to growing urban centers in Southern California is especially energy intensive, pushing local utilities to balance water security with factors such as the cost and carbon footprint of the various supply sources. To enhance water security, cities are expanding efforts to increase local water supply. But do these local sources have a smaller carbon footprint than imported sources? To answer this question and others related to the urban water-energy nexus, this study uses spatially explicit life cycle assessment to estimate the energy and emissions intensity of water supply for two utilities in Southern California: Los Angeles Department of Water and Power, which serves Los Angeles, and the Inland Empire Utility Agency, which serves the San Bernardino region. This study differs from previous research in two significant ways: (1) emissions factors are based not on regional averages but on the specific electric utility and generation sources supplying energy throughout transport, treatment, and distribution phases of the water supply chain; (2) upstream (non-combustion) emissions associated with the energy sources are included. This approach reveals that in case of water supply to Los Angeles, local recycled water has a higher carbon footprint than water imported from the Colorado River. In addition, by excluding upstream emissions, the carbon footprint of water supply is potentially underestimated by up to 30%. These results have wide-ranging implications for how carbon footprints are traditionally calculated at local and regional levels. Reducing the emissions intensity of local water supply hinges on transitioning the energy used to treat and distribute water away from fossil fuel, sources such as coal.

A seismic refraction and reflection study across the central San Jacinto Basin, Southern California

USGS Publications Warehouse

Lee, T.-C.; Biehler, S.; Park, S.K.; Stephenson, W.J.

1996-01-01

The San Jacinto Basin is a northwest-trending, pullapart basin in the San Jacinto fault zone of the San Andreas fault system in southern California. About 24 km long and 2 to 4 km wide, the basin sits on a graben bounded by two strands of the San Jacinto fault zone: the Claremont Fault on the northeast and the Casa Loma Fault on the southwest. We present a case study of shallow structure (less than 1 km) in the central basin. A 2.75-km refraction line running from the northeast to southwest across the regional structural trend reveals a groundwater barrier (Offset I). Another line, bent southward and continued for 1.65-km, shows a crystalline basement offset (Offset III) near an inferred trace of the Casa Loma Fault. Although a basement refractor was not observed along the 2.75-km line, a mismatch between the estimate of its minimum depth and the basement depth determined for the 1.65-km line suggests that an offset in the basement (greater than 260 m) exists around the junction of the two refraction lines (Offset II). By revealing more faults and subtle sedimentary structures, the reflection stack sections confirm the two refraction offsets as faults. Offsets I and III each separate sediments of contrasting structures and, in addition. Offset III disrupts an unconformity. However, the sense and amount of the offset across Offset III contradict what may be expected across the Casa Loma Fault, which has its basinward basement down-thrown to about 2.5 km in the better defined southeastern part of the graben. The Casa Loma Fault trace has been mislinked in the existing geological maps and the trace should be remapped to Offset II where the reflector disruptions spread over a 400-m wide zone. Our Offset III is an unnamed, concealed fault.

Detailed p- and s-wave velocity models along the LARSE II transect, Southern California

USGS Publications Warehouse

Murphy, J.M.; Fuis, G.S.; Ryberg, T.; Lutter, W.J.; Catchings, R.D.; Goldman, M.R.

2010-01-01

Structural details of the crust determined from P-wave velocity models can be improved with S-wave velocity models, and S-wave velocities are needed for model-based predictions of strong ground motion in southern California. We picked P- and S-wave travel times for refracted phases from explosive-source shots of the Los Angeles Region Seismic Experiment, Phase II (LARSE II); we developed refraction velocity models from these picks using two different inversion algorithms. For each inversion technique, we calculated ratios of P- to S-wave velocities (VP/VS) where there is coincident P- and S-wave ray coverage.We compare the two VP inverse velocity models to each other and to results from forward modeling, and we compare the VS inverse models. The VS and VP/VS models differ in structural details from the VP models. In particular, dipping, tabular zones of low VS, or high VP/VS, appear to define two fault zones in the central Transverse Ranges that could be parts of a positive flower structure to the San Andreas fault. These two zones are marginally resolved, but their presence in two independent models lends them some credibility. A plot of VS versus VP differs from recently published plots that are based on direct laboratory or down-hole sonic measurements. The difference in plots is most prominent in the range of VP = 3 to 5 km=s (or VS ~ 1:25 to 2:9 km/s), where our refraction VS is lower by a few tenths of a kilometer per second from VS based on direct measurements. Our new VS - VP curve may be useful for modeling the lower limit of VS from a VP model in calculating strong motions from scenario earthquakes.

Using species-specific paleotemperature equations with foraminifera: A case study in the Southern California Bight

USGS Publications Warehouse

Bemis, B.E.; Spero, H.J.; Thunell, R.C.

2002-01-01

Species-specific paleotemperature equations were used to reconstruct a record of temperature from foraminiferal ??18O values over the last 25 kyr in the Southern California Bight. The equations yield similar temperatures for the ??18O values of Globigerina bulloides and Neogloboquadrina pachyderma. In contrast, applying a single paleotemperature equation to G. bulloides and N. pachyderma ??18O yields different temperatures, which has been used to suggest that these species record the surface-to-thermocline temperature gradient. In Santa Barbara Basin, an isotopically distinct morphotype of G. bulloides dominates during glacial intervals and yields temperatures that appear too cold when using a paleotemperature equation calibrated for the morphotype common today. When a more appropriate paleotemperature equation is used for glacial G. bulloides, we obtain more realistic glacial temperatures. Glacial-interglacial temperature differences (G-I ??T) calculated in the present study indicate significant cooling (??? 8-10??C) throughout the Southern California Bight during the last glacial maximum (LGM). The magnitude of glacial cooling varies from ???8??C near the middle of the Southern California Bight (Tanner Basin and San Nicolas Basin) to ???9??C in the north (Santa Barbara Basin) and ???9.5-10??C in the south (Velero Basin and No Name Basin). Our temperature calculations agree well with previous estimates based on the modern analog technique. In contrast, studies using N. pachyderma coiling ratios, U37k??? indices, and transfer functions esfimate considerably warmer LGM temperatures and smaller G-I ??T. ?? 2002 Elsevier Science B.V. All rights reserved.

Assessing Temperature Risk to Crab in the Northeast Pacific (Southern California to the Beaufort Sea)

EPA Science Inventory

To evaluate the vulnerability of the Brachyura crabs (<200 m) to projected increases in sea surface temperature (SST), we developed an approach that evaluates risk within each of the ten Marine Ecoregions of the World (MEOW) ranging from Southern California to the Beaufort Sea...

Predictive equations for dimensions and leaf area of coastal Southern California street trees

Treesearch

P.J. Peper; E.G. McPherson; S.M. Mori

2001-01-01

Tree height, crown height, crown width, diameter at breast height (dbh), and leaf area were measured for 16 species of commonly planted street trees in the coastal southern California city of Santa Monica, USA. The randomly sampled trees were planted from 1 to 44 years ago. Using number of years after planting or dbh as explanatory variables, mean values of dbh, tree...

The Use of Two Professional Learning Community Practices in Elementary Classrooms and the English Language Arts Achievement of California's Most At-Risk Student Subgroups in a Southern California School District

ERIC Educational Resources Information Center

Mitchell, Carrie Lynn

2007-01-01

This study examines the impact of 2 professional learning community (PLC) classroom practices on the English Language Arts achievement of California's most at-risk subgroups between selected higher- and lower-performing elementary schools in a southern California school district. The conclusions from this study agree with the body of research,…

The Salton Seismic Imaging Project: Tomographic characterization of a sediment-filled rift valley and adjacent ranges, southern California

NASA Astrophysics Data System (ADS)

Davenport, K.; Hole, J. A.; Stock, J. M.; Fuis, G. S.; Carrick, E.; Tikoff, B.

2011-12-01

The Salton Trough in Southern California represents the northernmost rift of the Gulf of California extensional system. Relative motion between the Pacific and North American plates is accommodated by continental rifting in step-over zones between the San Andreas, Imperial, and Cerro Prieto transform faults. Rapid sedimentation from the Colorado River has isolated the trough from the southern portion of the Gulf of California, progressively filling the subsiding rift basin. Based on data from previous seismic surveys, the pre-existing continent has ruptured completely, and a new ~22 km thick crust has been created entirely by sedimentation overlying rift-related magmatism. The MARGINS, EarthScope, and USGS-funded Salton Seismic Imaging Project (SSIP) was designed to investigate the nature of this new crust, the ongoing process of continental rifting, and associated earthquake hazards. SSIP, acquired in March 2011, comprises 7 lines of onshore seismic refraction / wide-angle reflection data, 2 lines of refraction / reflection data in the Salton Sea, and a line of broadband stations. This presentation focuses on the refraction / wide-angle reflection line across the Imperial Valley, extending ~220 km across California from Otay Mesa, near Tijuana, to the Colorado River. The data from this line includes seventeen 100-160 kg explosive shots and receivers at 100 m spacing across the Imperial Valley to constrain the structure of the Salton Trough rift basin, including the Imperial Fault. Eight larger shots (600-920 kg) at 20-35 km spacing and receivers at 200-500 m spacing extend the line across the Peninsular Ranges and the Chocolate Mountains. These data will contrast the structure of the rift to that of the surrounding crust and provide constraints on whole-crust and uppermost mantle structure. Preliminary work has included tomographic inversion of first-arrival travel times across the Valley, emphasizing a minimum-structure approach to create a velocity model of the

Thinning – a tool for restoration of California's Southern Sierra Nevada blue oak woodlands

Treesearch

Richard B. Standiford; Ralph L. Phillips; Neil K. McDougald

2015-01-01

Fire frequency on a blue oak (Quercus douglasii) dominated rangeland in California's southern Sierra Nevada foothills was approximately every 10 years until 1965, followed by a 30 year period of fire exclusion. This resulted in a dense tree overstory with small diameters, high crown cover, poor acorn and forage production, and limited...

Modernization of the Caltech/USGS Southern California Seismic Network

NASA Astrophysics Data System (ADS)

Bhadha, R.; Devora, A.; Hauksson, E.; Johnson, D.; Thomas, V.; Watkins, M.; Yip, R.; Yu, E.; Given, D.; Cone, G.; Koesterer, C.

2009-12-01

The USGS/ANSS/ARRA program is providing Government Furnished Equipment (GFE), and two year funding for upgrading the Caltech/USGS Southern California Seismic Network (SCSN). The SCSN is the modern digital ground motion seismic network in southern California that monitors seismicity and provides real-time earthquake information products such as rapid notifications, moment tensors, and ShakeMap. The SCSN has evolved through the years and now consists of several well-integrated components such as Short-Period analog, TERRAscope, digital stations, and real-time strong motion stations, or about 300 stations. In addition, the SCSN records data from about 100 stations provided by partner networks. To strengthen the ability of SCSN to meet the ANSS performance standards, we will install GFE and carry out the following upgrades and improvements of the various components of the SCSN: 1) Upgrade of dataloggers at seven TERRAscope stations; 2) Upgrade of dataloggers at 131 digital stations and upgrade broadband sensors at 25 stations; 3) Upgrade of SCSN metadata capabilities; 4) Upgrade of telemetry capabilities for both seismic and GPS data; and 5) Upgrade balers at stations with existing Q330 dataloggers. These upgrades will enable the SCSN to meet the ANSS Performance Standards more consistently than before. The new equipment will improve station uptimes and reduce maintenance costs. The new equipment will also provide improved waveform data quality and consequently superior data products. The data gaps due to various outages will be minimized, and ‘late’ data will be readily available through retrieval from on-site storage. Compared to the outdated equipment, the new equipment will speed up data delivery by about 10 sec, which is fast enough for earthquake early warning applications. The new equipment also has about a factor of ten lower consumption of power. We will also upgrade the SCSN data acquisition and data center facilities, which will improve the SCSN

Deep resistivity sounding studies in detecting shear zones: A case study from the southern granulite terrain of India

NASA Astrophysics Data System (ADS)

Singh, S. B.; Stephen, Jimmy

2006-10-01

The resistivity signatures of the major crustal scale shear zones that dissect the southern granulite terrain (SGT) of South India into discrete geological fragments have been investigated. Resistivity structures deduced from deep resistivity sounding measurements acquired with a 10 km long Schlumberger spreads yield significant insights into the resistivity distribution within the E-W trending shear system comprising the Moyar-Bhavani-Salem-Attur shear zone (MBSASZ) and Palghat-Cauvery shear zone (PCSZ). Vertical and lateral extensions of low resistivity features indicate the possible existence of weak zones at different depths throughout the shear zones. The MBSASZ characterized by very low resistivity in its deeper parts (>2500 m), extends towards the south with slightly higher resistivities to encompass the PCSZ. A major resistivity transition between the northern and southern parts is evident in the two-dimensional resistivity images. The northern Archaean granulite terrain exhibits a higher resistivity than the southern Neoproterozoic granulite terrain. Though this resistivity transition is not clear at greater depths, the extension of low resistivity zones has been well manifested. It is speculated here that a network of crustal scale shear zones in the SGT may have influenced the strength of the lithosphere.

Shifting Climate Modes and a Warm Little Ice Age: Paleo Productivity and Temperature Determinations from the Southern California Current Over the Last Millennium

NASA Astrophysics Data System (ADS)

Kelly, C. S.; Herbert, T.; O'Mara, N. A.; Abella-Gutiérrez, J. L.; Herguera, J. C.

2016-12-01

The ocean dynamical thermostat hypothesis predicts that stronger [weaker] equatorial radiation forces warmer [cooler] western Pacific sea surface temperatures (SSTs) and a cooler [warmer] Eastern Equatorial Pacific (EEP) through air-sea coupling of the Walker circulation. Although proxy data offers some support for this prediction, recent SST reconstructions from the EEP suggest complex relationships between Northern Hemisphere (NH) and EEP temperature during the last millennium (Rustic et al. 2015), with EEP SSTs positively covarying with NH temperature during the Medieval Warm Period but negatively covarying during the Little Ice Age (LIA). Whereas most proxy reconstructions have focused on the EEP upwelling zone, few high-resolution studies exist from the California Current (CC)—a region whose oceanography displays exceptional fidelity to the El Niño Southern Oscillation and the Pacific Decadal Oscillation. In particular, southern CC oceanography reflects a balance between tropically-sourced and more northerly, temperate waters. Teasing these signals apart across past centuries can provide insight as to how a more complex dynamical thermostat affects the subtropics. Does the subtropical eastern Pacific track EEP SST across multiple centuries and climatic transitions? We present a record from the San Lazaro Basin (25N, 112.5W) in the subtropical eastern Pacific off Baja, Mexico of SST and marine paleoproductivity based upon alkenone saturation and concentrations (C37tot) over the last millennium. By combining these analyses on laminated sediment cores with newly published productivity records from the same site, we provide the first sub decadal paleoceanographic record from the southern California upwelling zone. We observe quasi-periodic short-lived cold excursions, centennial modulation of multidecadal periodicities, and an inverse relationship between C37tot and SST at lower frequencies. Our SST record displays a warm Little Ice Age, similar to but 100

Assembling and disassembling california: A zircon and monazite geochronologic framework for proterozoic crustal evolution in southern California

USGS Publications Warehouse

Barth, A.P.; Wooden, J.L.; Coleman, D.S.; Vogel, M.B.

2009-01-01

The Mojave province in southern California preserves a comparatively complete record of assembly, postorogenic sedimentation, and rifting along the southwestern North American continental margin. The oldest exposed rocks are metasedimentary gneisses and amphibolite, enclosing intrusive suites that range from tonalite and quartz mon-zodiorite to granite with minor trondhjemite. Discrete magmatic episodes occurred at approximately 1790-1730 and 1690-1640 Ma. Evidence from detrital and premagmatic zircons indicates that recycling of 1900-1790 Ma Paleopro-terozoic crust formed the unique isotopic character of the Mojave province. Peak metamorphic conditions in the Mojave province reached middle amphibolite to granulite facies; metamorphism occurred locally from 1795 to 1640 Ma, with widespread evidence for metamorphism at 1711-1689 and 1670-1650 Ma. Structures record early, tight to isoclinal folding and penetrative west-vergent shear during the final metamorphic event in the west Mojave province. Proterozoic basement rocks are overlain by siliciclastic-carbonate sequences of Mesoproterozoic, Neoproterozoic, and Cambrian age, recording environmental change over the course of the transition from stable Mojave crust to the rifted Cordilleran margin. Neoproterozoic quartzites have diverse zircon populations inconsistent with a southwest North American source, which we infer were derived from the western conjugate rift pair within Rodinia, before establishment of the miogeocline. Neoproterozoic-Cambrian miogeoclinal clastic rocks record an end to rifting and establishment of the Cordilleran miogeocline in southern California by latest Neoproterozoic to Early Cambrian time. ?? 2009 by The University of Chicago.

Resolution of fine biological structure including small narcomedusae across a front in the Southern California Bight

NASA Astrophysics Data System (ADS)

McClatchie, Sam; Cowen, Robert; Nieto, Karen; Greer, Adam; Luo, Jessica Y.; Guigand, Cedric; Demer, David; Griffith, David; Rudnick, Daniel

2012-04-01

We sampled a front detected by SST gradient, ocean color imagery, and a Spray glider south of San Nicolas Island in the Southern California Bight between 14 and 18 October 2010. We sampled the front with an unusually extensive array of instrumentation, including the Continuous Underway Fish Egg Sampler (CUFES), the undulating In Situ Ichthyoplankton Imaging System (ISIIS) (fitted with temperature, salinity, oxygen, and fluorescence sensors), multifrequency acoustics, a surface pelagic trawl, a bongo net, and a neuston net. We found higher fluorescence and greater cladoceran, decapod, and euphausiid densities in the front, indicating increased primary and secondary production. Mesopelagic fish were most abundant in oceanic waters to the west of the front, market squid were abundant in the front associated with higher krill and decapod densities, and jack mackerel were most common in the front and on the shoreward side of the front. Egg densities peaked to either side of the front, consistent with both offshore (for oceanic squid and mesopelagic fish) and shelf origins (for white croaker and California halibut). We discovered unusually high concentrations of predatory narcomedusae in the surface layer of the frontal zone. Potential ichthyoplankton predators were more abundant either in the front (decapods, euphausiids, and squid) or shoreward of the front (medusae, chaetognaths, and jack mackerel). For pelagic fish like sardine, which can thrive in less productive waters, the safest place to spawn would be offshore because there are fewer potential predators.

Sea Surface Temperature Influence on Terrestrial Gross Primary Production along the Southern California Current.

PubMed

Reimer, Janet J; Vargas, Rodrigo; Rivas, David; Gaxiola-Castro, Gilberto; Hernandez-Ayon, J Martin; Lara-Lara, Ruben

2015-01-01

Some land and ocean processes are related through connections (and synoptic-scale teleconnections) to the atmosphere. Synoptic-scale atmospheric (El Niño/Southern Oscillation [ENSO], Pacific Decadal Oscillation [PDO], and North Atlantic Oscillation [NAO]) decadal cycles are known to influence the global terrestrial carbon cycle. Potentially, smaller scale land-ocean connections influenced by coastal upwelling (changes in sea surface temperature) may be important for local-to-regional water-limited ecosystems where plants may benefit from air moisture transported from the ocean to terrestrial ecosystems. Here we use satellite-derived observations to test potential connections between changes in sea surface temperature (SST) in regions with strong coastal upwelling and terrestrial gross primary production (GPP) across the Baja California Peninsula. This region is characterized by an arid/semiarid climate along the southern California Current. We found that SST was correlated with the fraction of photosynthetic active radiation (fPAR; as a proxy for GPP) with lags ranging from 0 to 5 months. In contrast ENSO was not as strongly related with fPAR as SST in these coastal ecosystems. Our results show the importance of local-scale changes in SST during upwelling events, to explain the variability in GPP in coastal, water-limited ecosystems. The response of GPP to SST was spatially-dependent: colder SST in the northern areas increased GPP (likely by influencing fog formation), while warmer SST at the southern areas was associated to higher GPP (as SST is in phase with precipitation patterns). Interannual trends in fPAR are also spatially variable along the Baja California Peninsula with increasing secular trends in subtropical regions, decreasing trends in the most arid region, and no trend in the semi-arid regions. These findings suggest that studies and ecosystem process based models should consider the lateral influence of local-scale ocean processes that could

Sea Surface Temperature Influence on Terrestrial Gross Primary Production along the Southern California Current

PubMed Central

Reimer, Janet J.; Vargas, Rodrigo; Rivas, David; Gaxiola-Castro, Gilberto; Hernandez-Ayon, J. Martin; Lara-Lara, Ruben

2015-01-01

Some land and ocean processes are related through connections (and synoptic-scale teleconnections) to the atmosphere. Synoptic-scale atmospheric (El Niño/Southern Oscillation [ENSO], Pacific Decadal Oscillation [PDO], and North Atlantic Oscillation [NAO]) decadal cycles are known to influence the global terrestrial carbon cycle. Potentially, smaller scale land-ocean connections influenced by coastal upwelling (changes in sea surface temperature) may be important for local-to-regional water-limited ecosystems where plants may benefit from air moisture transported from the ocean to terrestrial ecosystems. Here we use satellite-derived observations to test potential connections between changes in sea surface temperature (SST) in regions with strong coastal upwelling and terrestrial gross primary production (GPP) across the Baja California Peninsula. This region is characterized by an arid/semiarid climate along the southern California Current. We found that SST was correlated with the fraction of photosynthetic active radiation (fPAR; as a proxy for GPP) with lags ranging from 0 to 5 months. In contrast ENSO was not as strongly related with fPAR as SST in these coastal ecosystems. Our results show the importance of local-scale changes in SST during upwelling events, to explain the variability in GPP in coastal, water-limited ecosystems. The response of GPP to SST was spatially-dependent: colder SST in the northern areas increased GPP (likely by influencing fog formation), while warmer SST at the southern areas was associated to higher GPP (as SST is in phase with precipitation patterns). Interannual trends in fPAR are also spatially variable along the Baja California Peninsula with increasing secular trends in subtropical regions, decreasing trends in the most arid region, and no trend in the semi-arid regions. These findings suggest that studies and ecosystem process based models should consider the lateral influence of local-scale ocean processes that could

77 FR 70487 - Southern California Edison Company; Establishment of Atomic Safety and Licensing Board

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-26

...] Southern California Edison Company; Establishment of Atomic Safety and Licensing Board Pursuant to... 2.104, 2.105, 2.300, 2.309, 2.313, 2.318, and 2.321, notice is hereby given that an Atomic Safety...), and the NRC Commission's November 8, 2012 decision in CLI-12-20 referring to the Atomic Safety and...

Crustal extension and transform faulting in the southern Basin Range Province. [California, Arizona, and Nevada

NASA Technical Reports Server (NTRS)

Liggett, M. A. (Principal Investigator); Childs, J. F.

1974-01-01

The author has identified the following significant results. Field reconnaissance and study of geologic literature guided by analysis of ERTS-1 MSS imagery have led to a hypothesis of tectonic control of Miocene volcanism, plutonism, and related mineralization in part of the Basin Range Province of southern Nevada and northwestern Arizona. The easterly trending right-lateral Las Vegas Shear Zone separates two volcanic provinces believed to represent areas of major east-west crustal extension. One volcanic province is aligned along the Colorado River south of the eastern termination of the Las Vegas Shear Zone; the second province is located north of the western termination of the shear zone in southern Nye County, Nevada. Geochronologic, geophysical, and structural evidence suggests that the Las Vegas Shear Zone may have formed in response to crustal extension in the two volcanic provinces in a manner similar to the formation of a ridge-ridge transform fault, as recognized in ocean floor tectonics.

75 FR 35652 - Safety Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, South Lake...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-23

... Zone; Northern California Annual Fireworks Events, Fourth of July Fireworks, South Lake Tahoe Gaming... will enforce Lights on the Lake Fireworks Display safety zone for South Lake Tahoe, from 8:30 a.m. on... the Lake Fireworks in 33 CFR 165.1191 on July 4, 2010, from 8:30 a.m. on July 1, 2010 through 10 p.m...

Tectonic creep in the Hayward fault zone, California

USGS Publications Warehouse

Radbruch-Hall, Dorothy H.; Bonilla, M.G.

1966-01-01

Tectonic creep is slight apparently continuous movement along a fault. Evidence of creep has been noted at several places within the Hayward fault zone--a zone trending northwestward near the western front of the hills bordering the east side of San Francisco Bay. D. H. Radbruch of the Geological Survey and B. J. Lennert, consulting engineer, confirmed a reported cracking of a culvert under the University of California stadium. F. B. Blanchard and C. L. Laverty of the East Bay Municipal Utility District of Oakland studied cracks in the Claremont water tunnel in Berkeley. M. G. Bonilla of the Geological Survey noted deformation of railroad tracks in the Niles district of Fremont. Six sets of tracks have been bent and shifted. L. S. Cluff of Woodward-Clyde-Sherard and Associates and K. V. Steinbrugge of the Pacific Fire Rating Bureau noted that the concrete walls of a warehouse in the Irvington district of Fremont have been bent and broken, and the columns forced out of line. All the deformations noted have been right lateral and range from about 2 inches in the Claremont tunnel to about 8 inches on the railroad tracks. Tectonic creep almost certainly will continue to damage buildings, tunnels, and other structures that cross the narrow bands of active movement within the Hayward fault zone.

The depth range of azimuthal anisotropy beneath Southern California via analyses of long-period Rayleigh-waves

NASA Astrophysics Data System (ADS)

Tsang, Stephanie Doris

The motion of the mantle beneath the tectonic plates is still unknown. Mantle shears associated with flow generate anisotropy. In order to investigate the anisotropic properties within the Earth to a range of depths within the crust and upper mantle (and perhaps beyond), long-period Rayleigh waves (periods of 51:282 ≤ T ≤ 333:33 seconds) are used in this study. One model suggests that the fast axis orientation, arising from the preferential alignment of olivine crystal grains in the upper mantle, coincides with the direction of absolute plate motion of the North-American plate. Other models suggest it is aligned with the direction of relative plate motion of the Pacific and North-American plates. A third suggests that an eastward mantle flow occurs beneath the North-American plate. There is also controversy as to the depth to which anisotropy is generated. In this thesis, the Rayleigh-wave phase velocities' dependence on a seismic event's back-azimuth angle is explored within the Southern California Seismic Network (SCSN). Because surface wave velocities vary depending on the range of depth into the Earth sampled by each period, an observed deviation of the resulting phase velocity calculations for a wide range of back-azimuth angles, (6° to 349°) with respect to a reference dispersion curve of the area, provides information on the anisotropy of the subsurface structure. Further work on the fast-axis orientation and its tectonic implications is carried out here. I find that the 2 directions 270° = 90° and 290° = 110° are possible fast-axes orientations. I also find that the amplitude of azimuthal anisotropy is insufficient to explain birefringence of S-body waves, also known as SKS splitting, suggesting that it occurs much deeper than previously thought, perhaps all the way to the transition zone. Future work might involve array analysis of Love-wave components using the beamforming approach. This approach should prove effective in

The Effect of Riparian Zones in Structuring Small Mammal Communities in the Southern Appalachians

Treesearch

Joshua Laerm; Michael A. Menzel; Dorothy J. Wolf; James R. Welch

1997-01-01

Riparian zones have been shown to be important in structuring vertebrate communities and in maintaining biodiversity. We examined the role of riparian zones in structuring small mammal communities in a southern Appalachian watershed at Coweeta Hydrological Laboratory, Macon County, North Carolina. We established pitfall and live-trap grids in three replicates each of...

Sedimentation across the central California oxygen minimum zone: an alternative coastal upwelling sequence.

USGS Publications Warehouse

Vercoutere, T.L.; Mullins, H.T.; McDougall, K.; Thompson, J.B.

1987-01-01

Distribution, abundance, and diversity of terrigenous, authigenous, and biogenous material provide evidence of the effect of bottom currents and oxygen minimum zone (OMZ) on continental slope sedimentation offshore central California. Three major OMZ facies are identified, along the upper and lower edges of OMZ and one at its core.-from Authors

Twin Convergence Zones

NASA Technical Reports Server (NTRS)

2002-01-01

NASA's QuikSCAT satellite has confirmed a 30-year old largely unproven theory that there are two areas near the equator where the winds converge year after year and drive ocean circulation south of the equator. By analyzing winds, QuikSCAT has found a year-round southern and northern Intertropical Convergence Zone. This find is important to climate modelers and weather forecasters because it provides more detail on how the oceans and atmosphere interact near the equator. The Intertropical Convergence Zone (ITCZ) is the region that circles the Earth near the equator, where the trade winds of both the Northern and Southern Hemispheres come together. North of the equator, strong sun and warm water of the equator heats the air in the ITCZ, drawing air in from north and south and causing the air to rise. As the air rises it cools, releasing the accumulated moisture in an almost perpetual series of thunderstorms. Satellite data, however, has confirmed that there is an ITCZ north of the equator and a parallel ITCZ south of the equator. Variation in the location of the ITCZ is important to people around the world because it affects the north-south atmospheric circulation, which redistributes energy. It drastically affects rainfall in many equatorial nations, resulting in the wet and dry seasons of the tropics rather than the cold and warm seasons of higher latitudes. Longer term changes in the ITCZ can result in severe droughts or flooding in nearby areas. 'The double ITCZ is usually only identified in the Pacific and Atlantic Oceans on a limited and seasonal basis,' said Timothy Liu, of NASA's Jet Propulsion Laboratory and California Institute of Technology, Pasadena, Calif., and lead researcher on the project. In the eastern Pacific Ocean, the southern ITCZ is usually seen springtime. In the western Atlantic Ocean, the southern ITCZ was recently clearly identified only in the summertime. However, QuikSCAT's wind data has seen the southern ITCZ in all seasons across the

Probable peak discharges and erosion rates from southern California watersheds as influenced by fire

Treesearch

P.B. Rowe; C.M. Countryman; H.C. Storey

1949-01-01

Damages from floods and erosion have been a serious problem in southern California since early pioneer days. The problem is becoming even more serious as the rapidly increasing population and expanding industrial and agricultural development encroach upon the flood plains and extend up the steep slopes and into canyons of the nearby mountains. Protection of forest...

Stability of exotic annual grasses following restoration efforts in southern California coastal sage scrub

Treesearch

Robert D. Cox; Edith B. Allen

2008-01-01

Restoration of semi-arid shrub ecosystems often requires control of invasive grasses but the effects of these grass-control treatments on native and exotic forbs have not been investigated adequately to assess long-term stability. In southern California, coastal sage scrub (CSS) vegetation is one semi-arid shrub community that has been invaded extensively by both...

Alteration of belowground carbon dynamics by nitrogen addition in southern California mixed conifer forests

Treesearch

N.S. Nowinski; S.E. Trumbore; G. Jimenez; M.E. Fenn

2009-01-01

Nitrogen deposition rates in southern California are the highest in North America and have had substantial effects on ecosystem functioning. We document changes in the belowground C cycle near ponderosa pine trees experiencing experimental nitrogen (N) addition (50 and 150 kg N ha−1 a−1 as slow release urea since 1997) at two end‐member...

Rapid climatic signal propagation from source to sink in a southern California sediment-routing system

USGS Publications Warehouse

Covault, J.A.; Romans, B.W.; Fildani, A.; McGann, M.; Graham, S.A.

2010-01-01

Terrestrial source areas are linked to deep-sea basins by sediment-routing systems, which only recently have been studied with a holistic approach focused on terrestrial and submarine components and their interactions. Here we compare an extensive piston-core and radiocarbon-age data set from offshore southern California to contemporaneous Holocene climate proxies in order to test the hypothesis that climatic signals are rapidly propagated from source to sink in a spatially restricted sediment-routing system that includes the Santa Ana River drainage basin and the Newport deep-sea depositional system. Sediment cores demonstrate that variability in rates of Holocene deep-sea turbidite deposition is related to complex ocean-atmosphere interactions, including enhanced magnitude and frequency of the North American monsoon and El Ni??o-Southern Oscillation cycles, which increased precipitation and fluvial discharge in southern California. This relationship is evident because, unlike many sediment-routing systems, the Newport submarine canyon-and-channel system was consistently linked tothe Santa Ana River,which maintained sediment delivery even during Holocene marine transgression and highstand. Results of this study demonstrate the efficiency of sediment transport and delivery through a spatially restricted, consistently linked routing system and the potential utility of deep-sea turbidite depositional trends as paleoclimate proxies in such settings. ?? 2010 by The University of Chicago.

Comparative analysis of sediments from the coast of southern California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, J.W.; Tjeerdema, R.; Newman, J.

1995-12-31

Sediment samples were collected in the summer of 1994 along the coast of the Southern California Bight, from Point Conception to the boarder with Mexico. Agencies involved in the program included EPA (EMAP), NOAA (ORCA), the state of California (State Water Board, California Dept. of Fish and Game, the University of Calif., Santa Cruz), major municipal waste dischargers (cities of Los Angeles and San Diego, Los Angeles and Orange Counties), and their research organization, SCCWRP. The level of effort in certain regions (bays) was more intensive than on the open coast, since there was an attempt to find ``hot spots``.more » For some of these sites the sediments were analyzed for inorganic and organic contaminants, toxicity to amphipods and echinoderm larvae, and a biomarker (P450 reporter gene system; RGS). The findings from chemical and biological testing on sediments from Orange County to San Diego Bay will be presented to demonstrate the range of contamination and the responses of the test species. Further comparisons between the concentrations of key contaminants and biological measures of toxicity will describe the correlations found, and the likelihood of identifying hot spots with toxicological endpoints. A strong correlation was found for the relationship between PAHs in sediments and the induction of P450 in a screening test system (RGS).« less

33 CFR 334.961 - Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Pacific Ocean, San Clemente... RESTRICTED AREA REGULATIONS § 334.961 Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore. (a) The danger zone: The waters of the Pacific Ocean adjacent to San Clemente...

33 CFR 334.961 - Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Pacific Ocean, San Clemente... RESTRICTED AREA REGULATIONS § 334.961 Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore. (a) The danger zone: The waters of the Pacific Ocean adjacent to San Clemente...

33 CFR 334.961 - Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Pacific Ocean, San Clemente... RESTRICTED AREA REGULATIONS § 334.961 Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore. (a) The danger zone: The waters of the Pacific Ocean adjacent to San Clemente...

33 CFR 334.961 - Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Pacific Ocean, San Clemente... RESTRICTED AREA REGULATIONS § 334.961 Pacific Ocean, San Clemente Island, California, naval danger zone off the northwest shore. (a) The danger zone: The waters of the Pacific Ocean adjacent to San Clemente...

Late Holocene tectonics and paleoseismicity, southern Cascadia subduction zone

USGS Publications Warehouse

Clarke, S.H.; Carver, G.A.

1992-01-01

Holocene deformation indicative of large subduction-zone earthquakes has occurred on two large thrust fault systems in the Humboldt Bay region of northern California. Displaced stratigraphic markers record three offsets of 5 to 7 meters each on the Little Salmon fault during the past 1700 years. Smaller and less frequent Holocene displacements have occurred in the Mad River fault zone. Elsewhere, as many as five episodes of sudden subsidence of marsh peats and fossil forests and uplift of marine terraces are recorded. Carbon-14 dates suggest that the faulting, subsidence, and uplift events were synchronous. Relations between magnitude and various fault-offset parameters indicate that earthquakes accompanying displacements on the Little Salmon fault had magnitudes of at least 7.6 to 7.8. More likely this faulting accompanied rupture of the boundary between the Gorda and North American plates, and magnitudes were about 8.4 or greater.

Late holocene tectonics and paleoseismicity, southern cascadia subduction zone.

PubMed

Clarke, S H; Carver, G A

1992-01-10

Holocene deformation indicative of large subduction-zone earthquakes has occurred on two large thrust fault systems in the Humboldt Bay region of northern California. Displaced stratigraphic markers record three offsets of 5 to 7 meters each on the Little Salmon fault during the past 1700 years. Smaller and less frequent Holocene displacements have occurred in the Mad River fault zone. Elsewhere, as many as five episodes of sudden subsidence of marsh peats and fossil forests and uplift of marine terraces are recorded. Carbon-14 dates suggest that the faulting, subsidence, and uplift events were synchronous. Relations between magnitude and various fault-offset parameters indicate that earthquakes accompanying displacements on the Little Salmon fault had magnitudes of at least 7.6 to 7.8. More likely this faulting accompanied rupture of the boundary between the Gorda and North American plates, and magnitudes were about 8.4 or greater.

Connecting crustal seismicity and earthquake-driven stress evolution in Southern California

USGS Publications Warehouse

Pollitz, Fred; Cattania, Camilla

2017-01-01

Tectonic stress in the crust evolves during a seismic cycle, with slow stress accumulation over interseismic periods, episodic stress steps at the time of earthquakes, and transient stress readjustment during a postseismic period that may last months to years. Static stress transfer to surrounding faults has been well documented to alter regional seismicity rates over both short and long time scales. While static stress transfer is instantaneous and long lived, postseismic stress transfer driven by viscoelastic relaxation of the ductile lower crust and mantle leads to additional, slowly varying stress perturbations. Both processes may be tested by comparing a decade-long record of regional seismicity to predicted time-dependent seismicity rates based on a stress evolution model that includes viscoelastic stress transfer. Here we explore crustal stress evolution arising from the seismic cycle in Southern California from 1981 to 2014 using five M≥6.5 source quakes: the M7.3 1992 Landers, M6.5 1992 Big Bear, M6.7 1994 Big Bear, M7.1 1999 Hector Mine, and M7.2 2010 El Mayor-Cucapah earthquakes. We relate the stress readjustment in the surrounding crust generated by each quake to regional seismicity using rate-and-state friction theory. Using a log likelihood approach, we quantify the potential to trigger seismicity of both static and viscoelastic stress transfer, finding that both processes have systematically shaped the spatial pattern of Southern California seismicity since 1992.

Archiving and Distributing Seismic Data at the Southern California Earthquake Data Center (SCEDC)

NASA Astrophysics Data System (ADS)

Appel, V. L.

2002-12-01

The Southern California Earthquake Data Center (SCEDC) archives and provides public access to earthquake parametric and waveform data gathered by the Southern California Seismic Network and since January 1, 2001, the TriNet seismic network, southern California's earthquake monitoring network. The parametric data in the archive includes earthquake locations, magnitudes, moment-tensor solutions and phase picks. The SCEDC waveform archive prior to TriNet consists primarily of short-period, 100-samples-per-second waveforms from the SCSN. The addition of the TriNet array added continuous recordings of 155 broadband stations (20 samples per second or less), and triggered seismograms from 200 accelerometers and 200 short-period instruments. Since the Data Center and TriNet use the same Oracle database system, new earthquake data are available to the seismological community in near real-time. Primary access to the database and waveforms is through the Seismogram Transfer Program (STP) interface. The interface enables users to search the database for earthquake information, phase picks, and continuous and triggered waveform data. Output is available in SAC, miniSEED, and other formats. Both the raw counts format (V0) and the gain-corrected format (V1) of COSMOS (Consortium of Organizations for Strong-Motion Observation Systems) are now supported by STP. EQQuest is an interface to prepackaged waveform data sets for select earthquakes in Southern California stored at the SCEDC. Waveform data for large-magnitude events have been prepared and new data sets will be available for download in near real-time following major events. The parametric data from 1981 to present has been loaded into the Oracle 9.2.0.1 database system and the waveforms for that time period have been converted to mSEED format and are accessible through the STP interface. The DISC optical-disk system (the "jukebox") that currently serves as the mass-storage for the SCEDC is in the process of being replaced

The Southern California Coastal Ocean Observing System (SCCOOS): Developing A Coastal Observation System To Enable Both Science Based Decision Making And Scientific Discovery

NASA Astrophysics Data System (ADS)

Terrill, E.; John, O.

2005-05-01

The Southern California Coastal Ocean Observing System (SCCOOS) is a consortium that extends from Northern Baja CA in Mexico to Morro Bay at the southern edge of central California, and aims to streamline, coordinate, and further develop individual institutional efforts by creating an integrated, multidisciplinary coastal observatory in the Bight of Southern California for the benefit of society. By leveraging existing infrastructure, partnerships, and private, local, state, and federal resources, SCCOOS is developing a fully operational coastal observation system to address issues related to coastal water quality, marine life resources, and coastal hazards for end user communities spanning local, state, and federal interests. However, to establish a sensible observational approach to address these societal drivers, sound scientific approaches are required in both the system design and the transformation of data to useful products. Since IOOS and coastal components of the NSF Ocean Observatories Initiative (OOI) are not mutually exclusive within this framework, the SCCOOS consortium of observatory implementers have created an organizational structure that encourages dovetailing of OOI into the routine observations provided by the operational components of a regional IOOS. To begin the development, SCCOOS has grant funding from the California Coastal Conservancy as part of a $21M, statewide initiative to establish a Coastal Ocean Currents Monitoring Program, and funding from NOAA's Coastal Observing Technology System (COTS). In addition, SCCOOS is leveraging IT development that has been supported by the NSF Information Technology Research program Real-time observatories, Applications,and Data Manageemnt Network (ROADNET), and anticipates using developments which will result from the NSF Laboratory for Ocean Observatory Knowledge Integration Grid (LOOKING) program. The observational components now funded at SCCOOS include surface current mapping by HF radar; high

Faulting, Seismicity and Stress Interaction in the Salton Sea Region of Southern California

NASA Astrophysics Data System (ADS)

Kilb, D. L.; Brothers, D. S.; Lin, G.; Kent, G.; Newman, R. L.; Driscoll, N.

2009-12-01

The Salton Sea region in southern California provides an ideal location to study the relationship between transcurrent and extensional motion in the northern Gulf of California margin, allowing us to investigate the spatial and temporal interaction of faults in the area and better understand their kinematics. In this region, the San Andreas Fault (SAF) and Imperial Fault present two major transform faults separated by the Salton Sea transtensional domain. Earthquakes over magnitude 4 in this area almost always have associated aftershock sequences. Recent seismic reflection surveys in the Salton Sea reveal that the majority of faults under the southern Salton Sea trend ~N15°E, appear normal-dominant and have very minimal associated microseismicity. These normal faults rupture every 100-300 years in large earthquakes and most of the nearby microseismicity locates east of the mapped surface traces. For example, there is profuse microseismicity in the Brawley Seismic Zone (BSZ), which is coincident with the southern terminus of the SAF as it extends offshore into the Salton Sea. Earthquakes in the BSZ are dominantly swarm-like, occurring along short (<5 km) ~N45°E oriented sinistral and N35°W oriented dextral fault planes. This mapped seismicity makes a rung-and-ladder pattern. In an effort to reconcile differences between processes at the surface and those at seismogenic depths we integrate near surface fault kinematics, geometry and paleoseismic history with seismic data. We identify linear and planer trends in these data (20 near surface faults, >20,000 relocated earthquakes and >2,000 earthquake focal mechanisms) and when appropriate estimate the fault strike and dip using principal component analysis. With our more detailed image of the fault structure we assess how static stress changes imparted by magnitude ~6.0 ruptures along N15E oriented normal faults beneath the Salton Sea can modulate the stress field in the BSZ and along the SAF. These tests include

Soil Flushing Through a Thick Vadose Zone: Perchlorate Removal Documented at Edwards AFB, California

NASA Astrophysics Data System (ADS)

Battey, T. F.; Shepard, A. J.; Tait, R. J.

2007-12-01

There are currently few viable alternatives for perchlorate remediation in the vadose zone, particularly for the relatively thick vadose zones that are typical in the arid southwest where many perchlorate sites occur. Perchlorate in the vadose zone occurs in the form of highly soluble salts that may represent a risk to human or ecological receptors, and may also represent a threat to the underlying groundwater. A soil flushing treatability study was conducted at Edwards Air Force Base in the Mojave Desert of southern California at a site with a 129-foot thick vadose zone consisting primarily of clayey sand. This study utilized an infiltration gallery in conjunction with extraction, treatment, and re-injection of groundwater at the site, which contained perchlorate-contaminated soil and groundwater. The study objective was to evaluate the effectiveness of the infiltration gallery to 1) introduce treated groundwater back into the aquifer and 2) wash the perchlorate from the vadose zone soils to the aquifer. The infiltration gallery consisted of slotted PVC pipes within a highly permeable engineered bed of washed gravel. The initial water introduced into the gallery was amended with potassium bromide tracer. A downhole neutron probe was used to track the movement of the wetting front downward and outward from the gallery. Successive neutron measurements in vertical access tubes revealed that the introduced water reached the 125-foot bottom of the access tubes 14 weeks after the water was introduced into the gallery. The bromide tracer was detected in groundwater immediately below the gallery approximately 1 week later. The infiltration gallery was able to sustain an average flow rate of 2.3 gallons per minute. Prior to infiltration, the perchlorate concentration in groundwater below the gallery was 4,500 µg/L. Approximately 18 weeks after the start of infiltration, a perchlorate spike of 72,400 µg/L was detected below the gallery. The increase in perchlorate

TriNet "ShakeMaps": Rapid generation of peak ground motion and intensity maps for earthquakes in southern California

USGS Publications Warehouse

Wald, D.J.; Quitoriano, V.; Heaton, T.H.; Kanamori, H.; Scrivner, C.W.; Worden, C.B.

1999-01-01

Rapid (3-5 minutes) generation of maps of instrumental ground-motion and shaking intensity is accomplished through advances in real-time seismographic data acquisition combined with newly developed relationships between recorded ground-motion parameters and expected shaking intensity values. Estimation of shaking over the entire regional extent of southern California is obtained by the spatial interpolation of the measured ground motions with geologically based frequency and amplitude-dependent site corrections. Production of the maps is automatic, triggered by any significant earthquake in southern California. Maps are now made available within several minutes of the earthquake for public and scientific consumption via the World Wide Web; they will be made available with dedicated communications for emergency response agencies and critical users.

Failure to Identify Borrelia burgdorferi in Southern California Ticks by DNA Amplification

DTIC Science & Technology

1993-01-01

reverse if necessary and identify by block, number) F;Et.D . &P SUB-GROUP ric..ettsial diseases, Lyme borreliosis , polymerase chain re on, I~~ I...DNA sequences of B. bur~dorfrri (as a positiv e control. B. burg- would be useful in assessino the risk of Lyme borreliosis in ex- dorferi alone was...vector. %%ell-documnented cases of Lyme borreliosis remain to the revised Centers for Disease Control and Prevention case rare in southern California

Using challenge cost-share partnerships to communicate with ethnically diverse recreation users in southern California

Treesearch

Thomas W. Spencer; Robert E. Pfister

1995-01-01

Recreation managers have established more effective communication with dispersed recreation users of the Angeles National Forest in southern California, through the development and use of Challenge Cost-Share Partnerships with regional non-profit organizations. From 1988 to 1990, researchers conducted a series of surveys of recreation visitor populations in the heavily...

Crustal architecture and tectonic evolution of the Cauvery Suture Zone, southern India

NASA Astrophysics Data System (ADS)

Chetty, T. R. K.; Yellappa, T.; Santosh, M.

2016-11-01

The Cauvery suture zone (CSZ) in southern India has witnessed multiple deformations associated with multiple subduction-collision history, with incorporation of the related accretionary belts sequentially into the southern continental margin of the Archaean Dharwar craton since Neoarchean to Neoproterozoic. The accreted tectonic elements include suprasubduction complexes of arc magmatic sequences, high-grade supracrustals, thrust duplexes, ophiolites, and younger intrusions that are dispersed along the suture. The intra-oceanic Neoarchean-Neoproterozoic arc assemblages are well exposed in the form of tectonic mélanges dominantly towards the eastern sector of the CSZ and are typically subjected to complex and multiple deformation events. Multi-scale analysis of structural elements with detailed geological mapping of the sub-regions and their structural cross sections, geochemical and geochronological data and integrated geophysical observations suggest that the CSZ is an important zone that preserves the imprints of multiple cycles of Precambrian plate tectonic regimes.

The Honey Lake fault zone, northeastern California: Its nature, age, and displacement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wagner, D.L.; Saucedo, G.J.; Grose, T.L.T.

The Honey Lake fault zone of northeastern California is composed of en echelon, northwest trending faults that form the boundary between the Sierra Nevada and the Basin Ranges provinces. As such the Honey Lake fault zone can be considered part of the Sierra Nevada frontal fault system. It is also part of the Walker Lane of Nevada. Faults of the Honey Lake zone are vertical with right-lateral oblique displacements. The cumulative vertical component of displacement along the fault zone is on the order of 800 m and right-lateral displacement is at least 10 km (6 miles) but could be considerablymore » more. Oligocene to Miocene (30 to 22 Ma) age rhyolite tuffs can be correlated across the zone, but mid-Miocene andesites do not appear to be correlative indicating the faulting began in early to mid-Miocene time. Volcanic rocks intruded along faults of the zone, dated at 16 to 8 Ma, further suggest that faulting in the Honey Lake zone was initiated during mid-Miocene time. Late Quaternary to Holocene activity is indicated by offset of the 12,000 year old Lake Lahontan high stand shoreline and the surface rupture associated with the 1950 Fort Sage earthquake.« less

AmeriFlux US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goulden, Michael

This is the AmeriFlux version of the carbon flux data for the site US-CZ4 Sierra Critical Zone, Sierra Transect, Subalpine Forest, Shorthair. Site Description - Half hourly data are available at https://www.ess.uci.edu/~california/. This site is one of four Southern Sierra Critical Zone Observatory flux towers operated along an elevation gradient (sites are USCZ1, USCZ2, USCZ3 and USCZ4). This site is a lodgepole pine subalpine woodland with no recent disturbance.

Birth Weight following Pregnancy during the 2003 Southern California Wildfires

PubMed Central

Holstius, David M.; Reid, Colleen E.; Jesdale, Bill M.

2012-01-01

Background: In late October 2003, a series of wildfires exposed urban populations in Southern California to elevated levels of air pollution over several weeks. Previous research suggests that short-term hospital admissions for respiratory outcomes increased specifically as a result of these fires. Objective: We assessed the impact of a wildfire event during pregnancy on birth weight among term infants. Methods: Using records for singleton term births delivered to mothers residing in California’s South Coast Air Basin (SoCAB) during 2001–2005 (n = 886,034), we compared birth weights from pregnancies that took place entirely before or after the wildfire event (n = 747,590) with those where wildfires occurred during the first (n = 60,270), second (n = 39,435), or third (n = 38,739) trimester. The trimester-specific effects of wildfire exposure were estimated using a fixed-effects regression model with several maternal characteristics included as covariates. Results: Compared with pregnancies before and after the wildfires, mean birth weight was estimated to be 7.0 g lower [95% confidence interval (CI): –11.8, –2.2] when the wildfire occurred during the third trimester, 9.7 g lower when it occurred during the second trimester (95% CI: –14.5, –4.8), and 3.3 g lower when it occurred during the first trimester (95% CI: –7.2, 0.6). Conclusions: Pregnancy during the 2003 Southern California wildfires was associated with slightly reduced average birth weight among infants exposed in utero. The extent and increasing frequency of wildfire events may have implications for infant health and development. PMID:22645279

River plume patterns and dynamics within the Southern California Bight

USGS Publications Warehouse

Warrick, J.A.; DiGiacomo, P.M.; Weisberg, S.B.; Nezlin, N.P.; Mengel, M.; Jones, B.H.; Ohlmann, J.C.; Washburn, L.; Terrill, E.J.; Farnsworth, K.L.

2007-01-01

Stormwater river plumes are important vectors of marine contaminants and pathogens in the Southern California Bight. Here we report the results of a multi-institution investigation of the river plumes across eight major river systems of southern California. We use in situ water samples from multi-day cruises in combination with MODIS satellite remote sensing, buoy meteorological observations, drifters, and HF radar current measurements to evaluate the dispersal patterns and dynamics of the freshwater plumes. River discharge was exceptionally episodic, and the majority of storm discharge occurred in a few hours. The combined plume observing techniques revealed that plumes commonly detach from the coast and turn to the left, which is the opposite direction of Coriolis influence. Although initial offshore velocity of the buoyant plumes was ∼50 cm/s and was influenced by river discharge inertia (i.e., the direct momentum of the river flux) and buoyancy, subsequent advection of the plumes was largely observed in an alongshore direction and dominated by local winds. Due to the multiple day upwelling wind conditions that commonly follow discharge events, plumes were observed to flow from their respective river mouths to down-coast waters at rates of 20–40 km/d. Lastly, we note that suspended-sediment concentration and beam-attenuation were poorly correlated with plume salinity across and within the sampled plumes (mean r2=0.12 and 0.25, respectively), while colored dissolved organic matter (CDOM) fluorescence was well correlated (mean r2=0.56), suggesting that CDOM may serve as a good tracer of the discharged freshwater in subsequent remote sensing and monitoring efforts of plumes.

76 FR 34859 - Safety Zone; Augusta Southern Nationals Drag Boat Race, Savannah River, Augusta, GA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-15

...-AA00 Safety Zone; Augusta Southern Nationals Drag Boat Race, Savannah River, Augusta, GA AGENCY: Coast... Boat Race. The Augusta Southern Nationals Drag Boat Race will consist of a series of high-speed boat... hazards associated with the high-speed boat races. Discussion of Rule From July 14, 2011 through July 17...

Linking Surface and Subsurface Processes: Implications for Seismic Hazards in Southern California

NASA Astrophysics Data System (ADS)

Lin, J. C.; Moon, S.; Yong, A.; Meng, L.; Martin, A. J.; Davis, P. M.

2017-12-01

Earth's surface and subsurface processes such as bedrock weathering, soil production, and river incision can influence and be influenced by spatial variations in the mechanical strength of surface material. Mechanically weakened rocks tend to have reduced seismic velocity, which can result in larger ground-motion amplification and greater potential for earthquake-induced damages. However, the influence and extent of surface and subsurface processes on the mechanical strength of surface material and seismic site conditions in southern California remain unclear. In this study, we examine whether physics-based models of surface and subsurface processes can explain the spatial variability and non-linearity of near-surface seismic velocity in southern California. We use geophysical measurements (Yong et al., 2013; Ancheta et al., 2014), consisting of shear-wave velocity (Vs) tomography data, Vs profiles, and the time-averaged Vs in the upper 30 m of the crust (Vs30) to infer lateral and vertical variations of surface material properties. Then, we compare Vs30 values with geologic and topographic attributes such as rock type, slope, elevation, and local relief, as well as metrics for surface processes such as soil production and bedrock weathering from topographic stress, frost cracking, chemical reactions, and vegetation presence. Results from this study will improve our understanding of physical processes that control subsurface material properties and their influences on local variability in seismic site conditions.

Exceptional Leadership in Exceptional Times: Perspectives and Ideologies of Special Education Directors in Southern California

ERIC Educational Resources Information Center

Diggs, Tangela R.

2016-01-01

The purpose of this qualitative phenomenological study was to explore the self-reported personal perspectives of special education directors in K-12 urban school districts in Southern California. Over 20,000 administrators oversee the delivery of special education services in the United States and the demand for such leadership exceeds the supply…

Response of Brown Creepers to elevation and forest edges in the southern Sierra Nevada, California

Treesearch

Kathryn Purcell; Craig Thompson; Douglas Drynan

2012-01-01

We studied the responses of the Brown Creeper (Certhia americana) to forest edges in the southern Sierra Nevada, California. We censused birds and monitored nests in four forest types over an elevational gradient. We identified habitat patches homogeneous in terms of forest type, seral stage, and canopy cover and rated edges between adjoining...

The Effects of El Niño on Precipitation in Southern California Climate Divisions: Year 2016 Precipitation Forecast.

NASA Astrophysics Data System (ADS)

Perez Cruz, L.; Idris, N.; El-Askary, H. M.

2015-12-01

Recently, it has been reported by the National Oceanic and Atmospheric Administration (NOAA) that there is very high chance not only for El Niño to continue through Northern Hemisphere winter 2015-16, but also a remarkable chance for El Niño to last into early spring 2016. This research aims at: 1) investigating the impact of El Niño on precipitation in the Southern California Climate Divisions: Climate Division 6 South Coast Drainage, and Division 7 South Coast Desert Basin. 2) Analyzing the precipitation of Southern California region using the Empirical Mode Decomposition Method (EMD). 3) Looking at the SOI components and compare it with the precipitation components of Southern California Climate Divisions. 4) Comparing precipitation data with Niño indices: Niño 1+2, Niño 3, Nino 3.4, and Niño 4. As results, we found a significant cross correlation of 0.7 between SOI component 10 and precipitation component 10 in Climate Division 6. Furthermore, among all the Niño indices, Niño 3 region displayed the best correlation. When we compared precipitation division 7 component 9 with Niño 3 component 10, a 0.95 cross correlation value was obtained. The lowest cross correlation value of (0.33) was obtained from Climate Division 6, precipitation component 7 with Niño 4 component 7.

Images of crust beneath southern California will aid study of earthquakes and their effects

USGS Publications Warehouse

Fuis, G.S.; Okaya, D.A.; Clayton, R.W.; Lutter, W.J.; Ryberg, T.; Brocher, T.M.; Henyey, T.M.; Benthien, M.L.; Davis, P.M.; Mori, J.; Catchings, R.D.; ten Brink, Uri S.; Kohler, M.D.; Klitgord, Kim D.; Bohannon, R.G.

1996-01-01

The Whittier Narrows earthquake of 1987 and the Northridge earthquake of 1991 highlighted the earthquake hazards associated with buried faults in the Los Angeles region. A more thorough knowledge of the subsurface structure of southern California is needed to reveal these and other buried faults and to aid us in understanding how the earthquake-producing machinery works in this region.

Recovery of aggraded stream channels at gauging stations in northern California and southern Oregon

Treesearch

T. E. Lisle

1981-01-01

Abstract - Discharge measurements at nine gauging stations in northern California and southern Oregon document episodes of channel bed aggradation lasting 5 to 15 years after the flood of December 1964 to January 1965. Bed elevations rose 1 to 4 m, then gradually declined to a stable level at or above the pre-flood level. Seven gauging sections widened by 7 to 105 per...

(Tele)presenting Secrets from the Deep Southern California Margin

NASA Astrophysics Data System (ADS)

Levin, L. A.; Girguis, P. R.; Brennan, M.; German, C. R.; Raineault, N.; Le, J. T.; Grupe, B.; Gallo, N.; Inderbitzen, K. E.; Tuzun, S.; Wagner, J.

2016-02-01

This past summer scientists, students and the public participated through telepresence in 2 weeks of deep-sea exploration via the EV Nautilus, visiting a tremendous diversity of sites found along the southern California continental margin (200-900m). We observed previously unknown cold seeps; new and unexpected assemblages and species distributions; and novel animal behaviors; all under the overarching influence of strong oxygen gradients from the East Pacific oxygen minimum zone (OMZ). The expedition discovered four new methane seep sites, each with distinct biota reflecting varying depth and oxygen levels. OMZ specialists such as lucinid clams, hagfish, and thornyhead fishes coexisted with seep biota (vesicoymid clams) at a 1.4-km long seep off Point Dume (Malibu, CA), forming a blended ecosystem with distinct zonation. A range of habitats (canyons, knolls, mounds) within the OMZ hosted fish, crustacean, echinoderm and cnidarian species with unusual hypoxia tolerance to < 3 µM O2 or lower. Organic falls (a sunken whale and naturally occurring kelp holdfasts) hosted many invertebrates and served as clear magnets for scavengers and predators. In situ observations revealed unusual behaviors including "parasailing" snails and drifting benthic siphonophores in the Santa Monica Basin, fish aggregating at seep carbonates, and cruising catsharks and their egg cases at methane seeps. Many of these observations advance understanding of the ecosystem services provided by deep-sea, margin habitats, while stimulating public interest in ocean exploration. Telepresence permitted broad engagement of students and scientists from as near as Los Angeles and as far as South Africa, as well as meaningful interactions with the public. In situ exploration and observation can and will play increasingly important roles in environmental management of the deep ocean as disturbance from resource extraction and climate change intensify.

A shallow-diving seabird predator as an indicator of prey availability in southern California waters: A longitudinal study

NASA Astrophysics Data System (ADS)

Horn, M. H.; Whitcombe, C. D.

2015-06-01

We tested the hypothesis that the Elegant Tern (Thalasseus elegans), a plunge-diving predator, is an indicator of changes in the prey community in southern California coastal waters. Shannon diversity (H‧) of the tern's diet determined from dropped fish collected variously at the three nesting sites for 18 years over a 21-year interval (1993-2013) showed no significant change in diet diversity. Based on a species-accumulation curve, total diet species represented about 70% of an extrapolated asymptotic richness. Abundance patterns of five prey species making up > 75% of prey numbers for all years were compared with abundance patterns of the same species in independent surveys obtained from zooplankton tows, bottom trawls and power-plant entrapments. Three of the five species - northern anchovy, kelp pipefish and California lizardfish - showed significant, positive correlations between diet and survey abundances. Even though the tern's diet has been dominated by anchovy and pipefish, its diet is still broad, with prey taxa representing > 75% of the 42 species groups making up the California shelf fish fauna. Altogether, our results support the hypothesis that the Elegant Tern, with its flexible diet, is a qualitative indicator, a sentinel, of changes in the prey communities in southern California coastal waters.

Extensive geographic and ontogenetic variation characterizes the trophic ecology of a temperate reef fish on southern California (USA) rocky reefs

PubMed Central

Hamilton, Scott L.; Caselle, Jennifer E.; Lantz, Coulson A.; Egloff, Tiana L.; Kondo, Emi; Newsome, Seth D.; Loke-Smith, Kerri; Pondella, Daniel J.; Young, Kelly A.; Lowe, Christopher G.

2015-01-01

Interactions between predator and prey act to shape the structure of ecological communities, and these interactions can differ across space. California sheephead Semicossyphus pulcher are common predators of benthic invertebrates in kelp beds and rocky reefs in southern California, USA. Through gut content and stable isotope (δ13C and †15N) analyses, we investigated geographic and ontogenetic variation in trophic ecology across 9 populations located at island and mainland sites throughout southern California. We found extensive geographic variation in California sheephead diet composition over small spatial scales. Populations differed in the proportion of sessile filter/suspension feeders or mobile invertebrates in the diet. Spatial variation in diet was highly correlated with other life history and demographic traits (e.g. growth, survivorship, reproductive condition, and energy storage), in addition to proxies of prey availability from community surveys. Multivariate descriptions of the diet from gut contents roughly agreed with the spatial groupings of sites based on stable isotope analysis of both California sheephead and their prey. Ontogenetic changes in diet occurred consistently across populations, despite spatial differences in size structure. As California sheephead increase in size, diets shift from small filter feeders, like bivalves, to larger mobile invertebrates, such as sea urchins. Our results indicate that locations with large California sheephead present, such as many marine reserves, may experience increased predation pressure on sea urchins, which could ultimately affect kelp persistence. PMID:26246648

Seismic attenuation structure beneath Nazca Plate subduction zone in southern Peru

NASA Astrophysics Data System (ADS)

Jang, H.; Kim, Y.; Clayton, R. W.

2017-12-01

We estimate seismic attenuation in terms of quality factors, QP and QS using P and S phases, respectively, beneath Nazca Plate subduction zone between 10°S and 18.5°S latitude in southern Peru. We first relocate 298 earthquakes with magnitude ranges of 4.0-6.5 and depth ranges of 20-280 km. We measure t*, which is an integrated attenuation through the seismic raypath between the regional earthquakes and stations. The measured t* are inverted to construct three-dimensional attenuation structures of southern Peru. Checkerboard test results for both QP and QS structures ensure good resolution in the slab-dip transition zone between flat and normal slab subduction down to a depth of 200 km. Both QP and QS results show higher attenuation continued down to a depth of 50 km beneath volcanic arc and also beneath the Quimsachata volcano, the northernmost young volcano, located far east of the main volcanic front. We also observe high attenuation in mantle wedge especially beneath the normal subduction region in both QP and QS (100-130 in QP and 100-125 in QS) and slightly higher QP and QS beneath the flat-subduction and slab-dip transition regions. We plan to relate measured attenuation in the mantle wedge to material properties such as viscosity to understand the subduction zone dynamics.

An Investigation of Plans and Procedures for Increasing Student Enrollments in Selected Southern California Community Colleges.

ERIC Educational Resources Information Center

Huguley, Sally M.

A study involving interviews with administrators at seven randomly selected Southern California community colleges was conducted to identify the marketing strategies undertaken by these institutions to increase student recruitment. During the interviews, respondents were asked to: (1) outline the functions of their public relations office; (2)…

Identification of two distinct fire regimes in Southern California: implications for economic impact and future change

Treesearch

Yufang Jin; Michael L. Goulden; Nicolas Faivre; Sander Veraverbeke; Fengpeng Sun; Alex Hall; Michael S. Hand; Simon Hook; James T. Randerson

2015-01-01

The area burned by Southern California wildfires has increased in recent decades, with implications for human health, infrastructure, and ecosystem management. Meteorology and fuel structure are universally recognized controllers of wildfire, but their relative importance, and hence the efficacy of abatement and suppression efforts, remains controversial....

Using Landsat-based evapotranspiration data to assess the linkages between water right transfers and economic transactions in southern California

NASA Astrophysics Data System (ADS)

Senay, G. B.; Velpuri, N. M.; Schauer, M.; Friedrichs, M.; Singh, R. K.

2017-12-01

We used 31 years (1984-2014) of cloud-free Landsat data (3,396 Landsat scenes) to estimate evapotranspiration over the southwestern United States using the Operational Simplified Surface Energy Balance (SSEBop) model. We focused on some of California's most agriculture-intensive watersheds (8 central valley watersheds and Palo Verde Irrigation District (PVID)). Farmers in southern California (including PVID) have water rights on the Colorado River. After meeting competing demands for agriculture (irrigation) and rural domestic use, the Colorado River is diverted to meet urban water demands in southern California. Due to the population growth and increasing domestic use, farmers have entered a special agreement to transfer their water rights under the fallowing program to the Metropolitan Water District (MWD) of southern California. MWD supplies water to 19 million people, more than half of California's population, and is the largest supplier of treated water in the United States. In this study, we presented the total annual volumetric water use in the Palo Verde Irrigation District since 1984 and computed historical annual crop water saved due to a fallowing program. We then converted volumetric water saved to total payouts to farmers in dollars and estimated the number of beneficiary households in the Greater Los Angeles area. It is interesting to see that nearly 120,000 acre-feet of water was transferred from PVID to MWD in 2011 and the cost of water payouts were over $20 million. This water saving met the demands of over 325,000 households in the Greater Los Angeles area. This analysis helps to a) demonstrate an approach to estimate and compare annual water use and water payments/savings using satellite data, b) monitor water rights compliance in an irrigation district, c) demonstrate the impact of water savings, and d) understand the interconnections between land-water management and socio-economic transactions across multiple spatio-temporal scales.

Insights into hydroclimatic variability of Southern California since 125 ka, from multi-proxy analyses of alpine lakes

NASA Astrophysics Data System (ADS)

Glover, K. C.; MacDonald, G. M.; Kirby, M.

2016-12-01

Hydroclimatic variability is especially important in California, a water-stressed and increasingly populous region. We assess the range of past hydroclimatic sensitivity and variability in the San Bernardino Mountains of Southern California based on 125 ka of lacustrine sediment records. Geochemistry, charcoal and pollen highlight periods of sustained moisture, aridity and sudden variability driven by orbital and oceanic variations. Marine Isotope Stage 3 (MIS 3) is one such period of greater moisture availability that lasted c. 30 kyr, with smaller-scale perturbations likely reflect North Atlantic Dansgaard-Oeschgar events. Past glacial periods, MIS 4 and MIS 2, display high-amplitude changes. These include periods of reduced forest cover that span millennia, indicating long-lasting aridity. Rapid forest expansion also occurs, marking sudden shifts towards wet conditions. Fire regimes have also changed in tandem with hydroclimate and vegetation. Higher-resolution analysis of the past 10 ka shows that Southern California hydroclimate was broadly similar to other regions of the Southwest and Great Basin, including an orbital and oceanic-driven wet Early Holocene, dry Mid-Holocene, and highly variable Late Holocene. Shorter-term pluvial conditions occur throughout the Holocene, with episodic moisture likely derived from a Pacific source.

Age and paleoenvironment of the imperial formation near San Gorgonio Pass, Southern California

USGS Publications Warehouse

McDougall, K.; Poore, R.Z.; Matti, J.

1999-01-01

Microfossiliferous marine sediments of the Imperial Formation exposed in the Whitewater and Cabazon areas, near San Gorgonio Pass, southern California, are late Miocene in age and were deposited at intertidal to outer neritic depths, and possibly upper bathyal depths. A late Miocene age of 7.4 to >6.04 Ma is based on the ranges of age-diagnostic benthic foraminifers (Cassidulina delicata and Uvigerina peregrina), planktic foraminifers (Globigerinoides obliquus, G. extremus, and Globigerina nepenthes; zones N17-N19), and calcareous nannoplankton (Discoaster brouweri, D. aff. D. surculus, Reticulofenestra pseudoumbilicata, Sphenolithus abies, and S. neoabies; zones CN9a-CN11) coupled with published K/Ar dates from the underlying Coachella Formation (10.1 ?? 1.2 Ma; Peterson, 1975) and overlying Painted Hill Formation (6.04 ?? 0.18 and 5.94 ?? 0.18 Ma; J. L. Morton in Matti and others, 1985 and Matti and Morton, 1993). Paleoecologic considerations (sea-level fluctuations and paleotemperature) restrict the age of the Imperial Formation to 6.5 through 6.3 Ma. Benthic foraminiferal assemblages indicate that the Imperial Formation in the Whitewater and Cabazon sections accumulated at inner neritic to outer neritic (0-152 m) and possibly upper bathyal (152-244 m) depths. Shallowing to inner neritic depths occurred as the upper part of the section was deposited. This sea-level fluctuation corresponds to a global highstand at 6.3 Ma (Haq and others, 1987). Planktic foraminifers suggest an increase in surface-water temperatures upsection. A similar increase in paleotemperatures is interpreted for the North Pacific from 6.5 to 6.3 Ma (warm interval W10 of Barron and Keller, 1983). Environmental contrasts between the Whitewater and Cabazon sections of the Imperial Formation provide evidence for right-lateral displacements on the Banning fault, a late Miocene strand of the San Andreas fault system. The Cabazon section lies south of the Banning fault, and has been displaced west

Geophysical characterization of transtensional fault systems in the Eastern California Shear Zone-Walker Lane Belt

NASA Astrophysics Data System (ADS)

McGuire, M.; Keranen, K. M.; Stockli, D. F.; Feldman, J. D.; Keller, G. R.

2011-12-01

The Eastern California Shear Zone (ECSZ) and Walker Lane belt (WL) accommodate ~25% of plate motion between the North American and Pacific plates. Faults within the Mina deflection link the ECSZ and the WL, transferring strain from the Owens Valley and Death Valley-Fish Lake Valley fault systems to the transcurrent faults of the central Walker Lane. During the mid to late Miocene the majority of strain between these systems was transferred through the Silver Peak-Lone Mountain (SPLM) extensional complex via a shallowly dipping detachment. Strain transfer has since primarily migrated north to the Mina Deflection; however, high-angle faults bounding sedimentary basins and discrepancies between geodetic and geologic models indicate that the SPLM complex may still actively transfer a portion of the strain from the ECSZ to the WL on a younger set of faults. Establishing the pattern and amount of active strain transfer within the SPLM region is required for a full accounting of strain accommodation, and provides insight into strain partitioning at the basin scale within a broader transtensional zone. To map the active structures in and near Clayton Valley, within the SPLM region, we collected seismic reflection and refraction profiles and a dense grid of gravity readings that were merged with existing gravity data. The primary goals were to determine the geometry of the high-angle fault system, the amount and sense of offset along each fault set, connectivity of the faults, and the relationship of these faults to the Miocene detachment. Seismic reflection profiles imaged the high-angle basin-bounding normal faults and the detachment in both the footwall and hanging wall. The extensional basin is ~1 km deep, with a steep southeastern boundary, a gentle slope to the northwest, and a sharp boundary on the northwest side, suggestive of another fault system. Two subparallel dip-slip faults bound the southeast (deeper) basin margin with a large lateral velocity change (from ~2

33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position 35...

33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position 35...

33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position 35...

33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position 35...

33 CFR 165.1155 - Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Nuclear Power Plant, Avila Beach, California. 165.1155 Section 165.1155 Navigation and Navigable Waters... Coast Guard District § 165.1155 Security Zone; Diablo Canyon Nuclear Power Plant, Avila Beach... surface to bottom, within a 2,000 yard radius of Diablo Canyon Nuclear Power Plant centered at position 35...

Domoic acid production near California coastal upwelling zones, June 1998

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trainer, V L.; Adams, Nicolaus G.; Bill, Brian D.

2000-01-01

Sea lion mortalities in central California during May and June 1998 were traced to their ingestion of sardines and anchovies that had accumulated the neurotoxin domoic acid. The detection of toxin in urine, feces, and stomach contents of several sea lions represents the first proven occurrence of domoic acid transfer through the food chain to a marine mammal. The pennate diatoms, Pseudo-nitzschia multiseries and P. australis, were the dominant, toxin-producing phytoplankton constituting algal blooms near Monterey Bay, Half Moon Bay, and Oceano Dunes, areas where sea lions with neurological symptoms stranded. Toxic Pseudo-nitzschia were also found near Morrow Bay, Pointmore » Conception, Point Arguello, and Santa Barbara, demonstrating that these species were widespread along the central California coast in June 1998. Measurements of domoic acid during three cruises in early June showed the highest cellular toxin levels in P. multiseries near Point A?o Nuevo and in P. australis from Morro w Bay. Maximum cellular domoic acid levels were observed within 20 km of the coast between 0 and 5 m depth, although toxin was also measured to depths of 40 m. Hydrographic data indicated that the highest toxin levels and greatest numbers of toxic cells were positioned in water masses associated with upwelling zones near coastal headlands. Nutrient levels at these sites were less than those typically measured during periods of active upwelling, due to the 1998 El Ni?o event. The flow of cells and/or nutrients from coastal headlands into embayments where cells can multiply in a stratified environment is a possible mechanism of bloom development along the central California coast. This coupling of toxic Pseudo-nitzschia growth near upwelling zones with physical processes involved in cell transport will be understood only when long-term measurements are made at several key coastal locations, aiding in our capability to predict domoic-acid producing algal blooms.« less

Sea Level Rise Drove Enhanced Coastal Erosion following the Last Glacial Maximum, Southern California, U.S.A.

NASA Astrophysics Data System (ADS)

Sharman, G.; Covault, J. A.; Stockli, D. F.; Sickmann, Z.; Malkowski, M. A.; Johnstone, S.

2017-12-01

Seacliff erosion poses a major threat to southern California coastal communities, including the propensity for episodic cliff failure and damage to residential and commercial property. Rising sea level is predicted to accelerate seacliff retreat, yet few constraints exist on how rapid sea level rise influenced coastal erosion rates in pre-modern timescales. Here we look to the geologic record in submarine fans to investigate changes in relative sediment supply from rivers and coastal erosion, the latter including seacliff retreat and bluffland erosion. To understand how sea level rise driven by past global warming impacted coastal erosion rates, we sampled modern rivers of the Peninsular Ranges and latest Pleistocene-Holocene submarine canyon-fan systems in southern California for detrital zircon U-Pb geochronology (1369 analyses from 10 samples). Modern river samples show a systematic north-south change in grain age populations broadly distributed across Cretaceous time (ca. 70-135 Ma) to a predominance of middle Cretaceous grain ages (ca. 95-115 Ma), reflecting variations in the geologic age of units within each river catchment. The Carlsbad and La Jolla submarine canyon-fan systems, deposited during sea level lowstand and highstand, respectively, exhibit detrital zircon age distributions consistent with derivation from upstream rivers, with mixing in the littoral zone. However, a sample from the Oceanside fan, deposited during rapid sea level rise at ca. 13 ka, is dominated by detrital ages that lack a local source in the northern Peninsular Ranges, including latest Cretaceous, late Jurassic, and Proterozoic ages. However, such grain ages are widespread in Paleogene sedimentary rocks that comprise the shelf and coastal area, suggesting increased sediment supply from coastal and shelf erosion. Assuming that the Oceanside sample is representative of sediment production during sea level rise, sediment mixing calculations suggest a one to two orders of magnitude

Demand Shifting with Thermal Mass in Large Commercial Buildings in a California Hot Climate Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Peng; Yin, Rongxin; Brown, Carrie

2009-06-01

The potential for using building thermal mass for load shifting and peak energy demand reduction has been demonstrated in a number of simulation, laboratory, and field studies. Previous Lawrence Berkeley National Laboratory research has demonstrated that the approach is very effective in cool and moderately warm climate conditions (California Climate Zones 2-4). However, this method had not been tested in hotter climate zones. This project studied the potential of pre-cooling the building early in the morning and increasing temperature setpoints during peak hours to reduce cooling-related demand in two typical office buildings in hotter California climates ? one in Visaliamore » (CEC Climate Zone 13) and the other in San Bernardino (CEC Climate Zone 10). The conclusion of the work to date is that pre-cooling in hotter climates has similar potential to that seen previously in cool and moderate climates. All other factors being equal, results to date indicate that pre-cooling increases the depth (kW) and duration (kWh) of the possible demand shed of a given building. The effectiveness of night pre-cooling in typical office building under hot weather conditions is very limited. However, night pre-cooling is helpful for office buildings with an undersized HVAC system. Further work is required to duplicate the tests in other typical buildings and in other hot climate zones and prove that pre-cooling is truly effective.« less

Composition of soil seed banks in southern California coastal sage scrub and adjacent exotic grassland

Treesearch

Robert D. Cox; Edith B. Allen

2008-01-01

Soil seed banks are important to many plant communities and are recognized as an important component of management plans. Understanding seed bank composition and density is especially important when communities have been invaded by exotic species and must be managed to promote desirable species. We examined germinable soil seed banks in southern California coastal sage...

Pliocene transpressional modification of depositional basins by convergent thrusting adjacent to the "Big Bend" of the San Andreas fault: An example from Lockwood Valley, southern California

USGS Publications Warehouse

Kellogg, K.S.; Minor, S.A.

2005-01-01

The "Big Bend" of the San Andreas fault in the western Transverse Ranges of southern California is a left stepping flexure in the dextral fault system and has long been recognized as a zone of relatively high transpression compared to adjacent regions. The Lockwood Valley region, just south of the Big Bend, underwent a profound change in early Pliocene time (???5 Ma) from basin deposition to contraction, accompanied by widespread folding and thrusting. This change followed the recently determined initiation of opening of the northern Gulf of California and movement along the southern San Andreas fault at about 6.1 Ma, with the concomitant formation of the Big Bend. Lockwood Valley occupies a 6-km-wide, fault-bounded structural basin in which converging blocks of Paleoproterozoic and Cretaceous crystalline basement and upper Oligocene and lower Miocene sedimentary rocks (Plush Ranch Formation) were thrust over Miocene and Pliocene basin-fill sedimentary rocks (in ascending order, Caliente Formation, Lockwood Clay, and Quatal Formation). All the pre-Quatal sedimentary rocks and most of the Pliocene Quatal Formation were deposited during a mid-Tertiary period of regional transtension in a crustal block that underwent little clockwise vertical-axis rotation as compared to crustal blocks to the south. Ensuing Pliocene and Quaternary transpression in the Big Bend region began during deposition of the poorly dated Quatal Formation and was marked by four converging thrust systems, which decreased the areal extent of the sedimentary basin and formed the present Lockwood Valley structural basin. None of the thrusts appears presently active. Estimated shortening across the center of the basin was about 30 percent. The fortnerly defined eastern Big Pine fault, now interpreted to be two separate, oppositely directed, contractional reverse or thrust faults, marks the northwestern structural boundary of Lockwood Valley. The complex geometry of the Lockwood Valley basin is similar

Webinar Presentation: Air Pollution, Social and Psychosocial Stress, and Respitory Health in the Southern California Children's Health Study

EPA Pesticide Factsheets

This presentation, Air Pollution, Social and Psychosocial Stress, and Respitory Health in the Southern California Children's Health Study, was given at the NIEHS/EPA Children's Centers 2016 Webinar Series: Exposome held on May 11, 2016.

A New Estimate for Total Offset on the Southern San Andreas Fault: Implications for Cumulative Plate Boundary Shear in the Northern Gulf of California

NASA Astrophysics Data System (ADS)

Darin, M. H.; Dorsey, R. J.

2012-12-01

-NAM) relative plate motion since ~12 Ma (Atwater and Stock, 1998). We propose that the continental component of PAC-NAM shear is accommodated by: (1) 195 ± 15 km on the southern SAF (this study); (2) 12 ± 2 km on the Whittier-Elsinore fault; (3) 75 ± 20 km of cumulative shear across the central Mojave in the eastern California shear zone; (4) 30 ± 4 km of post-13 Ma slip on the Stateline fault; and (5) 47 ± 18 km of NW-directed translation produced by north-south shortening. Together, these components sum to 359 ± 31 km of net dextral displacement on the SAF system (sensu lato) in southern California since ca. 12 Ma, or ~300 km less than what is required by the global plate circuit. This suggests that the continental component of post-12 Ma PAC-NAM transform motion can be no more than ~390 km in the adjacent northern Gulf of California, substantially less than the 450 km of shear proposed in some models. We suggest that the remaining ~270-300 km of NW-directed relative plate motion is accommodated by a small component of late Miocene extension and roughly 225 km of slip on the offshore borderland fault system west of Baja California.

76 FR 9348 - Southern California Edison Company, Pacific Gas and Electric Company, San Diego Gas & Electric...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-17

... Regulatory Policies Act of 1978 (PURPA),\\1\\ Southern California Edison Company (SCE), Pacific Gas and... Federal Energy Regulatory Commission (Commission) enforce the requirements of PURPA against the Public...\\ violate PURPA and the Commission's Regulations implementing PURPA. \\1\\ 16 U.S.C. 824a-3(h)(2) (2006). \\2...

Identification and interpretation of tectonic features from Skylab imagery. [California to Arizona

NASA Technical Reports Server (NTRS)

Abdel-Gawad, M. (Principal Investigator)

1974-01-01

The author has identified the following significant results. S190-B imagery confirmed previous conclusions from S190-A that the Garlock fault does not extend eastward beyond its known termination near the southern end of Death Valley. In the Avawatz Mountains, California, two faults related to the Garlock fault zone (Mule Spring fault and Leach Spring fault) show evidence of recent activity. There is evidence that faulting related to Death Valley fault zone extends southeastward across the Old Dad Mountains. There, the Old Dad fault shows evidence of recent activity. A significant fault lineament has been identified from McCullough Range, California southeastward to Eagle Tail Mountains in southwestern Arizona. The lineament appears to control tertiary and possible cretaceous intrusives. Considerable right lateral shear is suspected to have taken place along parts of this lineament.

Southern cascades bioregion

Treesearch

Carl N. Skinner; Alan H. Taylor

2006-01-01

The Cascade Range extends from British Columbia, Canada, south to northern California where it meets the Sierra Nevada. The Southern Cascades bioregion in California is bounded on the west by the Sacramento Valley and the Klamath Mountains, and on the east by the Modoc Plateau and Great Basin. The bioregion encompasses the Southern Cascades section of Miles and Goudey...

Carbon starvation in glacial trees recovered from the La Brea tar pits, southern California

Treesearch

Joy K. Ward; John M. Harris; Thure E. Cerling; Alex Wiedenhoeft; Michael J. Lott; Maria-Denise Dearing; Joan B. Coltrain; James R. Ehleringer

2005-01-01

The Rancho La Brea tar pit fossil collection includes Juniperus (C3) wood specimens that 14C date between 7.7 and 55 thousand years (kyr) B.P., providing a constrained record of plant response for southern California during the last glacial period. Atmospheric CO2 concentration ([CO2]) ranged between 180 and 220 ppm during glacial periods, rose to 280 ppm before the...

Conservation genetics of evolutionary lineages of the endangered mountain yellow-legged frog, Rana muscosa (Amphibia: Ranidae), in southern California

USGS Publications Warehouse

Schoville, Sean D.; Tustall, Tate S.; Vredenburg, Vance T.; Backlin, Adam R.; Gallegos, Elizabeth; Wood, Dustin A.; Fisher, Robert N.

2011-01-01

Severe population declines led to the listing of southern California Rana muscosa (Ranidae) as endangered in 2002. Nine small populations inhabit watersheds in three isolated mountain ranges, the San Gabriel, San Bernardino and San Jacinto. One population from the Dark Canyon tributary in the San Jacinto Mountains has been used to establish a captive breeding population at the San Diego Zoo Institute for Conservation Research. Because these populations may still be declining, it is critical to gather information on how genetic variation is structured in these populations and what historical inter-population connectivity existed between populations. Additionally, it is not clear whether these populations are rapidly losing genetic diversity due to population bottlenecks. Using mitochondrial and microsatellite data, we examine patterns of genetic variation in southern California and one of the last remaining populations of R. muscosa in the southern Sierra Nevada. We find low levels of genetic variation within each population and evidence of genetic bottlenecks. Additionally, substantial population structure is evident, suggesting a high degree of historical isolation within and between mountain ranges. Based on estimates from a multi-population isolation with migration analysis, these populations diversified during glacial episodes of the Pleistocene, with little gene flow during population divergence. Our data demonstrate that unique evolutionary lineages of R. muscosa occupy each mountain range in southern California and should be managed separately. The captive breeding program at Dark Canyon is promising, although mitigating the loss of neutral genetic diversity relative to the natural population might require additional breeding frogs.

California Fires

Atmospheric Science Data Center

2014-05-15

... title:  Smoke from Station Fire Blankets Southern California     View Larger Image ... that had not burned in decades, and years of extended drought contributed to the explosive growth of wildfires throughout southern ...

Active tectonics of the Imperial Valley, southern California: fault damage zones, complex basins and buried faults

NASA Astrophysics Data System (ADS)

Persaud, P.; Ma, Y.; Stock, J. M.; Hole, J. A.; Fuis, G. S.; Han, L.

2016-12-01

Ongoing oblique slip at the Pacific-North America plate boundary in the Salton Trough produced the Imperial Valley. Deformation in this seismically active area is distributed across a complex network of exposed and buried faults resulting in a largely unmapped seismic hazard beneath the growing population centers of El Centro, Calexico and Mexicali. To better understand the shallow crustal structure in this region and the connectivity of faults and seismicity lineaments, we used data primarily from the Salton Seismic Imaging Project (SSIP) to construct a P-wave velocity profile to 15 km depth, and a 3-D velocity model down to 8 km depth including the Brawley Geothermal area. We obtained detailed images of a complex wedge-shaped basin at the southern end of the San Andreas Fault system. Two deep subbasins (VP <5.65 km/s) are located in the western part of the larger Imperial Valley basin, where seismicity trends and active faults play a significant role in shaping the basin edge. Our 3-D VP model reveals previously unrecognized NE-striking cross faults that are interacting with the dominant NW-striking faults to control deformation. New findings in our profile include localized regions of low VP (thickening of a 5.65-5.85 km/s layer) near faults or seismicity lineaments interpreted as possibly faulting-related. Our 3-D model and basement map reveal velocity highs associated with the geothermal areas in the eastern valley. The improved seismic velocity model from this study, and the identification of important unmapped faults or buried interfaces will help refine the seismic hazard for parts of Imperial County, California.

Full-wave multiscale anisotropy tomography in Southern California

NASA Astrophysics Data System (ADS)

Lin, Yu-Pin; Zhao, Li; Hung, Shu-Huei

2014-12-01

Understanding the spatial variation of anisotropy in the upper mantle is important for characterizing the lithospheric deformation and mantle flow dynamics. In this study, we apply a full-wave approach to image the upper-mantle anisotropy in Southern California using 5954 SKS splitting data. Three-dimensional sensitivity kernels combined with a wavelet-based model parameterization are adopted in a multiscale inversion. Spatial resolution lengths are estimated based on a statistical resolution matrix approach, showing a finest resolution length of ~25 km in regions with densely distributed stations. The anisotropic model displays structural fabric in relation to surface geologic features such as the Salton Trough, the Transverse Ranges, and the San Andreas Fault. The depth variation of anisotropy does not suggest a lithosphere-asthenosphere decoupling. At long wavelengths, the fast directions of anisotropy are aligned with the absolute plate motion inside the Pacific and North American plates.

The Continued Reduction in Dense Fog in the Southern California Region: Possible Causes

NASA Astrophysics Data System (ADS)

LaDochy, S.; Witiw, M.

2012-05-01

Dense fog appears to be decreasing in many parts of the world, especially in western cities. Dense fog (visibility <400 m) is disappearing in the urban southern California area also. There the decrease in dense fog events can be explained mainly by declining particulate levels, Pacific sea surface temperatures (SST), and increased urban warming. Using hourly data from 1948 to the present, we looked at the relationship between fog events in the region and contributing factors and trends over time. Initially a strong relationship was suggested between the occurrence of dense fog and the phases of an atmosphere-ocean cycle: the Pacific Decadal Oscillation (PDO). However, closer analysis revealed the importance to fog variability of an increasing urban heat island and the amount of atmospheric suspended particulate matter. Results show a substantial decrease in the occurrence of very low visibilities (<400 m) at the two airport stations in close proximity to the Pacific Ocean, LAX (Los Angeles International) and LGB (Long Beach International). A downward trend in particulate concentrations, coupled with an upward trend in urban temperatures were associated with the decrease in dense fog occurrence at both LAX and LGB. LAX dense fog that reached over 300 h in 1950 dropped steadily, with 0 h recorded in 1997. Since 1997, there has been a slight recovery with both 2008 and 2009 recording over 30 h of dense fog at both locations. In this study we examine whether the upturn is a temporary reversal of the trend. To remove the urban effect, we also included fog data from Vandenberg Air Force Base (VBG), located in a relatively sparsely populated area approximately 200 km to the north of metropolitan Los Angeles. Particulates, urban heat island, and Pacific SSTs all seem to be contributing factors to the decrease in fog in southern California, along with large-scale atmosphere-ocean interaction cycles. Case studies of local and regional dense fog in southern California point

Dry atmospheric deposition rates of metals along a coastal transect in southern California

NASA Astrophysics Data System (ADS)

Sabin, Lisa D.; Schiff, Kenneth C.

While recent studies indicate atmospheric deposition is a significant source of metals to the Santa Monica Bay and coastal river systems of the Los Angeles area, the spatial extent of the atmospheric source along the entire southern California coast has not been measured in 30 years. This study provides measurements of dry atmospheric deposition of chromium, copper, lead, nickel and zinc at eight sites located along the coast between Santa Barbara and San Diego, and compares these data to historic measurements from the 1970s. Median dry deposition fluxes across sites ranged between 0.23 and 3.6 (chromium), 0.21 and 5.4 (nickel), 0.52 and 14 (lead), 0.89 and 29 (copper), and 4.8 and 160 (zinc) μg m -2 day -1. Differences in metal dry deposition rates observed between sites were dominated by proximity to urban areas and/or other nearby sources, with the highest metal fluxes observed near the Los Angeles Harbor (LAH) and San Diego Bay (SDB) sites. Compared with data from the 1970s, lead fluxes were typically one to two orders of magnitude lower in the present study (2006), indicating atmospheric sources of this metal have decreased over the past three decades in southern California. Chromium fluxes were also lower in 2006 compared with the 1970s, although to a lesser extent than for lead. In contrast, copper and zinc fluxes were typically within the same order of magnitude between the two time periods, with some higher measurements observed in 2006 compared with the 1970s at the LAH and SDB sites. This result indicates atmospheric sources of copper and zinc have not decreased over the past three decades in southern California, and have increased near our harbor/urban sites. Differences in sampling conditions (e.g., Santa Ana winds) and measurement techniques may also explain, in part, the differences observed in metal flux rates for these time periods. However, these limitations were most important for those metals with the smallest difference in flux rates measured

Using Adjoint Methods to Improve 3-D Velocity Models of Southern California

NASA Astrophysics Data System (ADS)

Liu, Q.; Tape, C.; Maggi, A.; Tromp, J.

2006-12-01

We use adjoint methods popular in climate and ocean dynamics to calculate Fréchet derivatives for tomographic inversions in southern California. The Fréchet derivative of an objective function χ(m), where m denotes the Earth model, may be written in the generic form δχ=int Km(x) δln m(x) d3x, where δln m=δ m/m denotes the relative model perturbation. For illustrative purposes, we construct the 3-D finite-frequency banana-doughnut kernel Km, corresponding to the misfit of a single traveltime measurement, by simultaneously computing the 'adjoint' wave field s† forward in time and reconstructing the regular wave field s backward in time. The adjoint wave field is produced by using the time-reversed velocity at the receiver as a fictitious source, while the regular wave field is reconstructed on the fly by propagating the last frame of the wave field saved by a previous forward simulation backward in time. The approach is based upon the spectral-element method, and only two simulations are needed to produce density, shear-wave, and compressional-wave sensitivity kernels. This method is applied to the SCEC southern California velocity model. Various density, shear-wave, and compressional-wave sensitivity kernels are presented for different phases in the seismograms. We also generate 'event' kernels for Pnl, S and surface waves, which are the Fréchet kernels of misfit functions that measure the P, S or surface wave traveltime residuals at all the receivers simultaneously for one particular event. Effectively, an event kernel is a sum of weighted Fréchet kernels, with weights determined by the associated traveltime anomalies. By the nature of the 3-D simulation, every event kernel is also computed based upon just two simulations, i.e., its construction costs the same amount of computation time as an individual banana-doughnut kernel. One can think of the sum of the event kernels for all available earthquakes, called the 'misfit' kernel, as a graphical

33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., Carquinez Strait, Suisun Bay, California. (a) Locations. The following areas are security zones: (1) Chevron... sea floor within approximately 100 yards of the Chevron Long Wharf, Richmond, CA, and encompasses all...

33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Carquinez Strait, Suisun Bay, California. (a) Locations. The following areas are security zones: (1) Chevron... sea floor within approximately 100 yards of the Chevron Long Wharf, Richmond, CA, and encompasses all...

33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Carquinez Strait, Suisun Bay, California. (a) Locations. The following areas are security zones: (1) Chevron... sea floor within approximately 100 yards of the Chevron Long Wharf, Richmond, CA, and encompasses all...

33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., Carquinez Strait, Suisun Bay, California. (a) Locations. The following areas are security zones: (1) Chevron... sea floor within approximately 100 yards of the Chevron Long Wharf, Richmond, CA, and encompasses all...

33 CFR 165.1197 - Security Zones; San Francisco Bay, San Pablo Bay, Carquinez Strait, Suisun Bay, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., Carquinez Strait, Suisun Bay, California. (a) Locations. The following areas are security zones: (1) Chevron... sea floor within approximately 100 yards of the Chevron Long Wharf, Richmond, CA, and encompasses all...

California Burn Scars

Atmospheric Science Data Center

2014-05-15

article title:  Burn Scars Across Southern California     ... California between October 21 and November 18, 2003. Burn scars and vegetation changes wrought by the fires are illustrated in these ... and Nov 18, 2003 Images:  California Burn Scars location:  United States region:  ...

The 2003 and 2007 wildfires in southern California: Chapter 5 in Natural Disasters and Adaptation to Climate Change

USGS Publications Warehouse

Keeley, Jon E.; Syphard, Alexandra D.; Fotheringham, C.J.; Boulter, Sarah; Palutikof, Jean; Karoly, David John; Guitart, Daniela

2013-01-01

Although many residents of southern California have long recognised that wildfires in the region are an ongoing, constant risk to lives and property, the enormity of the regional fire hazard caught the world’s attention during the southern California firestorms of 2003 (Figure 5.1). Beginning on 21 October, a series of fourteen wildfires broke out across the five-county region under severe Santa Ana winds, and within two weeks, more than 300,000 ha had burned (Keeley et al., 2004). The event was one of the costliest in the state’s history, with more than 3,600 homes damaged or destroyed and twenty-four fatalities. Suppression costs for the 12,000 firefighters have been estimated at US$120 million, and the total response and damage cost has been estimated at more than US$3 billion (COES, 2004). [Excerpt

Cruise report: RV Ocean Alert Cruise A2-98-SC: mapping the southern California continental margin; March 26 through April 11, 1998; San Diego to Long Beach, California

USGS Publications Warehouse

Gardner, James V.; Mayer, Larry A.

1998-01-01

The major objective of cruise A2-98 was to map portions of the southern California continental margin, including mapping in detail US Environmental Protection Agency (USEPA) ocean dumping sites. Mapping was accomplished using a high-resolution multibeam mapping system. The cruise was a jointly funded project between the USEPA and the US Geological Survey (USGS). The USEPA is specifically interested in a series of ocean dump sites off San Diego, Newport Beach, and Long Beach (see Fig. 1 in report) that require high-resolution base maps for site monitoring purposes. The USGS Coastal and Marine Geology Program has several on-going projects off southern California that lack high-precision base maps for a variety of ongoing geological studies. The cruise was conducted under a Cooperative Agreement between the USGS and the Ocean Mapping Group, University of New Brunswick, Canada.

Vertical crustal movements in Southern California, 1974 to 1978

USGS Publications Warehouse

Burford, R.O.; Gilmore, Thomas D.

1984-01-01

An extensive resurvey of most of the first-order leveling network in southern California, known as the Southern California Releveling Program (SCRP), was carried out during the first 5 months of 1978. The primary scientific purpose of these measurements was to rapidly update the vertical control record throughout a recently uplifted region of southern California in order to more thoroughly document the vertical component of tectonic movement and to provide a reliable base for comparison with future levelings. Analyses of historic first-order leveling results have clearly demonstrated that a broad crustal upwarping, largely contained within a region consisting of the Transverse Ranges province and an area along the intervening section of the San Andreas fault system, had developed between about 1959 and 1974. Unfortunately, there is strong evidence that parts of the 1978 SCRP data are contaminated by the effects of intrasurvey tectonic deformation, limited surficial failures, and, less certainly, magnetically induced systematic error associated with the use of automatic levels. However, any distortions in leveling results caused by these or other factors are not so serious as to render the SCRP data useless. In fact, the bulk of these data can be accepted at face value, and most of the remaining data can be incorporated with some caution to augment the more reliable parts of the network. The evaluation of the 1978 leveling is based on a combination of circuit-misclosures, local timing of the field observations, analysis of profiles of apparent height changes derived from comparisons with previous levelings, and an analysis of the position and orientation of the various routes in relation to the regional structural grain and the gradients of differential vertical motion established by previous investigations. Comparisons of the 1978 SCRP results with the latest of the previous surveys along each route retained in the analysis show that all but about one-third of the

Evaluating the effectiveness of burned area emergency response (BAER) efforts after the 2003 wildfires, southern California

Treesearch

Peter M. Wohlgemuth; Ken R. Hubbert; Jan L. Beyers; David R. Weise

2007-01-01

Wildfires burned approximately 300,000 hectares (750,000 acres) across southern California in the fall of 2003. Over 10 million dollars were spent on Burned Area Emergency Response (BAER) treatments following these fires. To support the BAER efforts, we designed a comprehensive strategy with standardized protocols to evaluate the effectiveness of various erosion...

Rainbow trout responses to water temperature and dissolved oxygen stress in two southern California stream pools

Treesearch

K.R. Matthews; N.H. Berg

1997-01-01