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202. A high-resolution surface vector wind product for coastal oceans: Blending satellite scatterometer measurements with regional mesoscale atmospheric model simulations

Author

Chao, Yi, Li, Zhijin, Kindle, John C., Paduan, Jeffrey D., Chavez, Francisco P., and Oceanography

Abstract

The article of record as published may be located at http://dx.doi.org/10.10 29/2002GL015729, 2003 A 2-dimensional variational method is used to blend the satellite scatterometer measured (QuikSCAT) and regional mesoscale atmospheric model simulated (COAMPS) surface vector winds for coastal central California. The approach is distinct from existing methods in that it considers errors from both measurements and models. When compared with independent in situ observations, the blended wind product shows consistently higher correlation and smaller RMS errors than QuikSCAT or COAMPS winds. The proposed algorithm can be implemented over any part of the world ocean. It should be a valuable tool for describing small-scale atmospheric processes in coastal zones and for forcing highresolution coastal ocean models. The research described in this paper was carried out, in part, at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA). Support from National Oceanographic Partnership Program (NOPP) is acknowledged. The participation of JCK was also funded through the Naval Research Laboratory (NRL) 6.1 CoBALT ARI and the Dynamics of Coupled Models project under program element 61153N sponsored by the Office of Naval Research.

Published
2003

203. The United States' next generation of atmospheric composition and coastal ecosystem measurements : NASA's Geostationary Coastal and Air Pollution Events (GEO-CAPE) Mission

Author

Fishman, J., Iraci, L. T., Al-Saadi, J., Chance, K., Chavez, Francisco P., Chin, M., Coble, Paula G., Davis, Curtiss O., DiGiacomo, P. M., Edwards, D., Eldering, A., Goes, Joachim I., Herman, J., Hu, Chuanmin, Jacob, Daniel J., Jordan, C., Kawa, S. Randolph, Key, R., Liu, X., Lohrenz, Steven E., Mannino, Antonio, Natraj, V., Neil, D., Neu, J., Newchurch, M. J., Pickering, K., Salisbury, Joseph E., Sosik, Heidi M., Subramaniam, A., Tzortziou, Maria, Wang, Jian, Wang, M., Fishman, J., Iraci, L. T., Al-Saadi, J., Chance, K., Chavez, Francisco P., Chin, M., Coble, Paula G., Davis, Curtiss O., DiGiacomo, P. M., Edwards, D., Eldering, A., Goes, Joachim I., Herman, J., Hu, Chuanmin, Jacob, Daniel J., Jordan, C., Kawa, S. Randolph, Key, R., Liu, X., Lohrenz, Steven E., Mannino, Antonio, Natraj, V., Neil, D., Neu, J., Newchurch, M. J., Pickering, K., Salisbury, Joseph E., Sosik, Heidi M., Subramaniam, A., Tzortziou, Maria, Wang, Jian, and Wang, M.

Abstract

Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 93 (2012): 1547–1566, doi:10.1175/BAMS-D-11-00201.1., The Geostationary Coastal and Air Pollution Events (GEO-CAPE) mission was recommended by the National Research Council's (NRC's) Earth Science Decadal Survey to measure tropospheric trace gases and aerosols and coastal ocean phytoplankton, water quality, and biogeochemistry from geostationary orbit, providing continuous observations within the field of view. To fulfill the mandate and address the challenge put forth by the NRC, two GEO-CAPE Science Working Groups (SWGs), representing the atmospheric composition and ocean color disciplines, have developed realistic science objectives using input drawn from several community workshops. The GEO-CAPE mission will take advantage of this revolutionary advance in temporal frequency for both of these disciplines. Multiple observations per day are required to explore the physical, chemical, and dynamical processes that determine tropospheric composition and air quality over spatial scales ranging from urban to continental, and over temporal scales ranging from diurnal to seasonal. Likewise, high-frequency satellite observations are critical to studying and quantifying biological, chemical, and physical processes within the coastal ocean. These observations are to be achieved from a vantage point near 95°–100°W, providing a complete view of North America as well as the adjacent oceans. The SWGs have also endorsed the concept of phased implementation using commercial satellites to reduce mission risk and cost. GEO-CAPE will join the global constellation of geostationary atmospheric chemistry and coastal ocean color sensors planned to be in orbit in the 2020 time frame., Funding for GEO-CAPE definition activities is provided by the Earth Science Division of the National Aeronautics and Space Administration., 2013-04-01

Published
2013

204. Pattern and synchrony of gene expression among sympatric marine microbial populations

Author

Massachusetts Institute of Technology. Department of Biological Engineering, Massachusetts Institute of Technology. Department of Civil and Environmental Engineering, Ottesen, Elizabeth, Young III, Curtis Robert, Eppley, John Marmaduke, DeLong, Edward, Ryan, John P., Chavez, Francisco P., Scholin, Christopher A., Massachusetts Institute of Technology. Department of Biological Engineering, Massachusetts Institute of Technology. Department of Civil and Environmental Engineering, Ottesen, Elizabeth, Young III, Curtis Robert, Eppley, John Marmaduke, DeLong, Edward, Ryan, John P., Chavez, Francisco P., and Scholin, Christopher A.

Abstract

Planktonic marine microbes live in dynamic habitats that demand rapid sensing and response to periodic as well as stochastic environmental change. The kinetics, regularity, and specificity of microbial responses in situ, however, are not well-described. We report here simultaneous multitaxon genome-wide transcriptome profiling in a naturally occurring picoplankton community. An in situ robotic sampler using a Lagrangian sampling strategy enabled continuous tracking and repeated sampling of coherent microbial populations over 2 d. Subsequent RNA sequencing analyses yielded genome-wide transcriptome profiles of eukaryotic (Ostreococcus) and bacterial (Synechococcus) photosynthetic picoplankton as well as proteorhodopsin-containing heterotrophs, including Pelagibacter, SAR86-cluster Gammaproteobacteria, and marine Euryarchaea. The photosynthetic picoplankton exhibited strong diel rhythms over thousands of gene transcripts that were remarkably consistent with diel cycling observed in laboratory pure cultures. In contrast, the heterotrophs did not cycle diurnally. Instead, heterotrophic picoplankton populations exhibited cross-species synchronous, tightly regulated, temporally variable patterns of gene expression for many genes, particularly those genes associated with growth and nutrient acquisition. This multitaxon, population-wide gene regulation seemed to reflect sporadic, short-term, reversible responses to high-frequency environmental variability. Although the timing of the environmental responses among different heterotrophic species seemed synchronous, the specific metabolic genes that were expressed varied from taxon to taxon. In aggregate, these results provide insights into the kinetics, diversity, and functional patterns of microbial community response to environmental change. Our results also suggest a means by which complex multispecies metabolic processes could be coordinated, facilitating the regulation of matter and energy processing in a dynamically cha, National Science Foundation (U.S.) (Science and Technology Center Award EF0424599), Gordon and Betty Moore Foundation, Agouron Institute, David & Lucile Packard Foundation

Published
2013

205. Phylogenetically conserved resource partitioning in the coastal microbial loop

Author

Bryson, Samuel, Li, Zhou, Chavez, Francisco, Weber, Peter K, Pett-Ridge, Jennifer, Hettich, Robert L, Pan, Chongle, Mayali, Xavier, and Mueller, Ryan S

Abstract

Resource availability influences marine microbial community structure, suggesting that population-specific resource partitioning defines discrete niches. Identifying how resources are partitioned among populations, thereby characterizing functional guilds within the communities, remains a challenge for microbial ecologists. We used proteomic stable isotope probing (SIP) and NanoSIMS analysis of phylogenetic microarrays (Chip-SIP) along with 16S rRNA gene amplicon and metagenomic sequencing to characterize the assimilation of six 13C-labeled common metabolic substrates and changes in the microbial community structure within surface water collected from Monterey Bay, CA. Both sequencing approaches indicated distinct substrate-specific community shifts. However, observed changes in relative abundance for individual populations did not correlate well with directly measured substrate assimilation. The complementary SIP techniques identified assimilation of all six substrates by diverse taxa, but also revealed differential assimilation of substrates into protein and ribonucleotide biomass between taxa. Substrate assimilation trends indicated significantly conserved resource partitioning among populations within the Flavobacteriia, Alphaproteobacteria and Gammaproteobacteria classes, suggesting that functional guilds within marine microbial communities are phylogenetically cohesive. However, populations within these classes exhibited heterogeneity in biosynthetic activity, which distinguished high-activity copiotrophs from low-activity oligotrophs. These results indicate distinct growth responses between populations that is not apparent by genome sequencing alone.

Published
2017
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206. El Niño along the west coast of North America, Editorial

Author

Chavez, Francisco P., Collins, Curtis A., Huyer, Adriana, and Mackas, David L.

Abstract

The fisherman of northern Peru coined the name El Niño in the late nineteenth century for a warm southward current that appeared every year around Christmas (the Christ child – El Niño). Years of unusually high rainfall in northern Peru were associated with an intensification of the annual current. It was not until the 1960s that Bjerknes (1966) linked warming of the coastal ocean off Peru (and the equatorial Pacific) with larger scale climatic phenomena. It was then that a relatively small and inoffensive coastal current (Chavez, 1986) was associated with dramatic global weather disturbances. Over the last 30 years the influence of El Niño on oceanic and atmospheric conditions throughout the globe has been well documented (Rasmusson and Wallace, 1983; Philander, 1990). More recently, in the 1980s, Peruvian scientists coined the name La Niña for anomalously cool temperatures along Peru. This phenomenon also has significant climatic impacts.

Published
2002

207. The 1997-8 El Nino atlas of oceanographic conditions along the West Coast of North America (23oN-50oN)

Author

Baumgartner, Timothy R., Chavez, Francisco P., Collins, Curtis A., Mascarenhas, Affonso S., Robert, Mari, Michisaki, Reiko, Bograd, Steven, Castro, Ruben, Durazo, Reginaldo, Garcia, Joaquin, Gaziola-Castro, Gilberto, Hayward, Thomas, Huyer, Adriana, Lynn, Ron, Naval Postgraduate School (U.S.)., and Dept. of Oceanography.

Subjects
OCEANOGRAPHIC DATA
Abstract

http://archive.org/details/19978elninoatlas00mich NA

Published
2001

208. Preface / Deep-Sea Research II, Volume 45 (1998)

Author

Chavez, Francisco P. and Collins, Curtis A.

Abstract

Ecosystems of the eastern boundary regions of the ocean basins, like those off California, Northwest Africa and Peru, are known for enhanced primary production and resulting large clupeid fisheries. In these eastern boundary regions, the basin-scale circulation brings the thermocline, pycnocline and nutricline close to the surface and often in contact with the mixed layer. Processes such as coastal upwelling then act to bring these cool and nutrient-rich waters to the surface. Photosynthesis is stimulated by the enhanced nutrient supply to sunlit waters, and food for supporting the ecosystem is generated. The source and fate of this primary production is variable, reflecting the dynamic physical character of eastern boundary systems. The physical and biological variability are most notable on mesoscale or subseasonal (upwelling events, jets and eddies), seasonal (spring transition, upwelling, winter) and interannual (El Nifio) scales. Decadal and interdecadal oscillations are evident in the longer time series (Hayward, 1996; Ingraham Jr. et al., 1998) and the analysis of White et al. (1997) suggests that the Northeast Pacific, and the California Coast in particular, are regions of higher than average decadal and interdecadal variability. And of course, the shadow of global warming looms on the horizon, if not already underway. Considering these factors, and the planning and implementation of major multi-disciplinary programs along the West Coast of North America (GLOBEC, CoOP), we have assembled a series of papers dealing with the oceanography of California waters into a volume of Deep Sea Research II.

Published
1998

213. Factors influencing nitrification rates and the abundance and transcriptional activity of ammonia-oxidizing microorganisms in the dark northeast Pacific Ocean.

Author

Smith, Jason M., Damashek, Julian, Chavez, Francisco P., and Francis, Christopher A.

Subjects
NITRIFICATION, GENE regulatory networks, AMMONIA-oxidizing bacteria, PELAGIC cormorant, OXIDATION of ammonia, NITROGEN cycle
Abstract

Pelagic marine Thaumarchaea play a primary role in ammonia oxidation, an integral part of nitrification and the nitrogen cycle. This study examines how physicochemical and biological variables influence rates of nitrification and the distribution, abundance and activity of ammonia oxidizers throughout the dark northeast Pacific Ocean. Nitrification rates are highest near the epipelagic-upper mesopelagic transition and decrease with depth according to a Martin-like power function, suggestive of a coupling to the organic matter flux. In contrast, archaeal and bacterial ammonia monooxygenase ( amoA) gene abundance remains fairly constant throughout the upper mesopelagic. Density-based composites reveal nitrification to be highest in the upper pycnocline, within the nitrate:silica and ammonium maxima, while ammonia-oxidizing archaea (AOA) abundances are highest in the lower pycnocline. Water column group A (WCA) and B (WCB) AOA amoA genes are present throughout the dark ocean but have no relationship to nitrification rates. WCA comprise the majority of the AOA community above 200 m and WCB comprise the majority of it below 500 m, largely because WCA abundances decrease precipitously from 200 m to 500 m. WCA and WCB amoA genes are actively transcribed throughout the dark ocean, irrespective of conditions. Thaumarchaeal urease ( ureC) genes are also present throughout, implying a widespread capacity for mixotrophy; however, unlike amoA, their expression is not detectable. Together, the results support a strong linkage between organic matter flux and nitrification rates, identify density as an important control over AOA distributions, and suggest that WCA and WCB distributions are influenced by the availability of their preferred substrates in the dark ocean. [ABSTRACT FROM AUTHOR]

Published
2016
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214. The State of the California Current, 1996-1997: Mixed Signals from the Tropics

Author

Schwing, Franklin B., Murphree, Tom, Mantyla, Arnold W., Hayward, Thomas L., Mascarenas, Affonso S. Jr., Cummings, Sherry L., Sakuma, Keith M., Castillo, Sergio I. Larios, Chavez, Francisco P., Baltz, Kenneth, Ainley, David G., and Meterorology

Abstract

Schwing et al.: The California Current, 1996-1997, CalCOFI Rep., Vol. 38, 1997 A large number of data sets from within the California Current region, and the large-scale fields that affect this region, are available for timely assessment of recent environmental conditions in this system. In addition to the long-running quarterly CalCOFI cruises, which featured the initial research cruise of RV Roger Revelle, several surveys off Baja California and central California have provided information on coastal areas adjacent to the present CalCOFI coverage. Conditions throughout the north Pacific and in the California Current are summarized and interpreted for the 1996-97 period.

Published
1997

215. Alkaline phosphatase activity in the phytoplankton communities of Monterey Bay and San Francisco Bay

Author

Nicholson, David P., Dyhrman, Sonya T., Chavez, Francisco P., Paytan, Adina, Nicholson, David P., Dyhrman, Sonya T., Chavez, Francisco P., and Paytan, Adina

Abstract

Author Posting. © American Society of Limnology and Oceanography, 2006. This is the author's version of the work. It is posted here by permission of American Society of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography 51 (2006): 874–883., Enzyme-labeled fluorescence (ELF) and bulk alkaline phosphatase (AP) activity enzyme assays were used to evaluate the phosphorus (P) status of phytoplankton communities in San Francisco and Monterey bays. Both regions exhibit spatial and temporal variability in bulk AP activity with maximum activities during the early spring and summer periods of high biological productivity. ELF analysis revealed pronounced differences in the makeup of organisms responsible for AP activity in these two environments. In Monterey Bay dinoflagellates are responsible for the bulk of the AP activity. Diatoms infrequently exhibited AP activity. Dinoflagellates that comprised only 14% of all cells counted in Monterey Bay accounted for 78% of AP-producing cells examined. The presence of AP activity in this group suggests that changes in P sources, concentrations, and bioavailability could disproportionably influence this group relative to diatoms in Monterey Bay. In San Francisco Bay, AP production, indicated by ELF, was associated primarily with bacteria attached to suspended particles, potentially used to hydrolyze organic compounds for carbon, rather than to satisfy P requirements. Our results highlight the importance of organic P as a bioavailable nutrient source in marine ecosystems and as a component of the marine P cycle.

Published
2006

220. The origins of the anomalous warming in the California coastal ocean and San Francisco Bay during 2014–2016

Author

Chao, Yi, Farrara, John D., Bjorkstedt, Eric, Chai, Fei, Chavez, Francisco, Rudnick, Daniel L., Enright, Wendy, Fisher, Jennifer L., Peterson, William T., Welch, Gregory F., Davis, Curtiss O., Dugdale, Richard C., Wilkerson, Frances P., Zhang, Hongchun, Zhang, Yinglong, and Ateljevich, Eli

Abstract

During 2014 exceptionally warm water temperatures developed across a wide area off the California coast and within San Francisco Bay (SFB) and persisted into 2016. Observations and numerical model output are used to document this warming and determine its origins. The coastal warming was mostly confined to the upper 100 m of the ocean and was manifested strongly in the two leading modes of upper ocean (0–100 m) temperature variability in the extratropical eastern Pacific. Observations suggest that the coastal warming in 2014 propagated into nearshore regions from the west while later indicating a warming influence that propagated from south to north into the region associated with the 2015–2016 El Niño event. An analysis of the upper ocean (0–100 m) heat budget in a Regional Ocean Modeling System (ROMS) simulation confirmed this scenario. The results from a set of sensitivity runs with the model in which the lateral boundary conditions varied supported the conclusions drawn from the heat budget analysis. Concerning the warming in the SFB, an examination of the observations and the heat budget in an unstructured‐grid numerical model simulation suggested that the warming during the second half of 2014 and early 2016 originated in the adjacent California coastal ocean and propagated through the Golden Gate into the Bay. The finding that the coastal and Bay warming are due to the relatively slow propagation of signals from remote sources raises the possibility that such warming events may be predictable many months or even several seasons in advance. The origins of the exceptionally warm water temperatures that developed off the California coast and in San Francisco Bay were studied using observations and computer model experiments. The coastal warming was mostly confined to the upper ocean. The coastal warming in 2014 was found to have moved into coastal waters from further offshore in the northeastern Pacific. Warming persisted into 2015‐2016 as a warming influence from the south associated with the 2015‐16 El Niño event in the tropical Pacific Ocean. The model experiments suggested confirmed that propagation of the warming signals from the west and north into the California coastal ocean and suggested that the warming in San Francisco Bay was found to have originated primarily in the adjacent California coastal ocean. The finding that the coastal and Bay warming are due to the relatively slow propagation of signals from remote sources raises the possibility that such warming events may be predictable many months or even several seasons in advance. Observations and model heat budget analyses show warming to be a result of propagation of signals from the west (Blob) and south (El Niño)Results from model sensitivity experiments support the conclusions drawn from the heat budget analysesThe relatively slow propagation of the remote signals means that such warming events may be predictable months in advance

Published
2017
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225. Modeling the Central California Coastal Upwelling System: Physics, Ecosystems and Resource Management

Author

MONTEREY BAY AQUARIUM RESEARCH INST MOSS LANDING CA, Chavez, Francisco P., Barber, Richard T., Chai, Fei, Chao, Yi, De Vogelaere, Andrew P., Kindle, John C., Maffione, Robert A., Marinovic, Baldo, McWilliams, James C., Paduan, Jeffrey D., MONTEREY BAY AQUARIUM RESEARCH INST MOSS LANDING CA, Chavez, Francisco P., Barber, Richard T., Chai, Fei, Chao, Yi, De Vogelaere, Andrew P., Kindle, John C., Maffione, Robert A., Marinovic, Baldo, McWilliams, James C., and Paduan, Jeffrey D.

Abstract

To develop a coupled physical-biological model that can utilize available data to accurately simulate physical, chemical and biological processes within the Monterey Bay National Marine Sanctuary (MBNMS). To use the model to better understand the central California coastal upwelling ecosystem. To develop better methods for management and protection of the California coast ecosystem as a valuable natural resource. To better understand the physical and biogeochemical dynamics of the California coastal upwelling system and how it responds to changes in local and large-scale atmospheric forcing, and global change., A National Oceanographic Partnership Program Award. The original document contains color images.

Published
2003

226. A high-resolution surface vector wind product for coastal oceans: Blending satellite scatterometer measurements with regional mesoscale atmospheric model simulations

Author

Oceanography, Chao, Yi, Li, Zhijin, Kindle, John C., Paduan, Jeffrey D., Chavez, Francisco P., Oceanography, Chao, Yi, Li, Zhijin, Kindle, John C., Paduan, Jeffrey D., and Chavez, Francisco P.

Abstract

A 2-dimensional variational method is used to blend the satellite scatterometer measured (QuikSCAT) and regional mesoscale atmospheric model simulated (COAMPS) surface vector winds for coastal central California. The approach is distinct from existing methods in that it considers errors from both measurements and models. When compared with independent in situ observations, the blended wind product shows consistently higher correlation and smaller RMS errors than QuikSCAT or COAMPS winds. The proposed algorithm can be implemented over any part of the world ocean. It should be a valuable tool for describing small-scale atmospheric processes in coastal zones and for forcing highresolution coastal ocean models.

Published
2003

227. Targeted metagenomics and ecology of globally important uncultured eukaryotic phytoplankton

Author

Cuvelier, Marie L., primary, Allen, Andrew E., additional, Monier, Adam, additional, McCrow, John P., additional, Messié, Monique, additional, Tringe, Susannah G., additional, Woyke, Tanja, additional, Welsh, Rory M., additional, Ishoey, Thomas, additional, Lee, Jae-Hyeok, additional, Binder, Brian J., additional, DuPont, Chris L., additional, Latasa, Mikel, additional, Guigand, Cédric, additional, Buck, Kurt R., additional, Hilton, Jason, additional, Thiagarajan, Mathangi, additional, Caler, Elisabet, additional, Read, Betsy, additional, Lasken, Roger S., additional, Chavez, Francisco P., additional, and Worden, Alexandra Z., additional

Published
2010
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228. Science in support of ecosystem-based management for the US West Coast and beyond

Author

Lester, Sarah E., primary, McLeod, Karen L., additional, Tallis, Heather, additional, Ruckelshaus, Mary, additional, Halpern, Benjamin S., additional, Levin, Phillip S., additional, Chavez, Francisco P., additional, Pomeroy, Caroline, additional, McCay, Bonnie J., additional, Costello, Christopher, additional, Gaines, Steven D., additional, Mace, Amber J., additional, Barth, John A., additional, Fluharty, David L., additional, and Parrish, Julia K., additional

Published
2010
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229. An Innovative Coastal-Ocean Observing Network (ICON)

Author

CALIFORNIA STATE UNIV SEASIDE, Fernandez, Daniel M., Paduan, Jeffrey D., Chavez, Francisco P., Shulman, Igor, Vesecky, John F., CALIFORNIA STATE UNIV SEASIDE, Fernandez, Daniel M., Paduan, Jeffrey D., Chavez, Francisco P., Shulman, Igor, and Vesecky, John F.

Abstract

The Innovative Coastal-Ocean Observing Network (ICON) is a partnership of government, academic, and industrial entities funded by the National Ocean Partnership Program (NOPP). Its goal is to bring together modern measurement technologies, to develop new technologies, and to integrate them within a data assimilating coastal ocean circulation model. The major components of the observing network include: (1) surface current maps from shore-based high frequency (HF) radar installations; (2) subsurface currents, temperature, salinity, and bio-optical properties plus surface meteorological properties from several deep-ocean moorings; (3) sea surface temperature and color from satellites; and (4) along-track temperature and temperature variances from two acoustic tomography slices through the region. The model performance is quite good at seasonal time scales, which is a validation of the one-way nesting because these variations are successfully tracked by the PWC regional-scale model. At higher frequencies, the model does not reproduce the observed level of variability. For the a long shore currents down to 150 meter depth, data assimilation resulted in greater correlation between modeled and observed currents.

Published
2002

230. Modeling the Central California Coastal Upwelling System: Physics, Ecosystems and Resource Management

Author

MONTEREY BAY AQUARIUM RESEARCH INST MOSS LANDING CA, Chavez, Francisco P., Barber, Richard T., Chai, Fei, Chao, Yi, De Vogelaere, Andrew P., Kindle, John C., Maffione, Robert A., Marinovic, Baldo, McWilliams, James C., Paduan, Jeffery D., MONTEREY BAY AQUARIUM RESEARCH INST MOSS LANDING CA, Chavez, Francisco P., Barber, Richard T., Chai, Fei, Chao, Yi, De Vogelaere, Andrew P., Kindle, John C., Maffione, Robert A., Marinovic, Baldo, McWilliams, James C., and Paduan, Jeffery D.

Abstract

A National Oceanographic Partnership Program Award. The original document contains color images.

Published
2002

238. The 1997-8 El Nino atlas of oceanographic conditions along the West Coast of North America (23oN-50oN)

Author

Naval Postgraduate School (U.S.)., Dept. of Oceanography., Baumgartner, Timothy R., Chavez, Francisco P., Collins, Curtis A., Mascarenhas, Affonso S., Robert, Mari, Michisaki, Reiko, Bograd, Steven, Castro, Ruben, Durazo, Reginaldo, Garcia, Joaquin, Gaziola-Castro, Gilberto, Hayward, Thomas, Huyer, Adriana, Lynn, Ron, Naval Postgraduate School (U.S.)., Dept. of Oceanography., Baumgartner, Timothy R., Chavez, Francisco P., Collins, Curtis A., Mascarenhas, Affonso S., Robert, Mari, Michisaki, Reiko, Bograd, Steven, Castro, Ruben, Durazo, Reginaldo, Garcia, Joaquin, Gaziola-Castro, Gilberto, Hayward, Thomas, Huyer, Adriana, and Lynn, Ron

Published
2001

242. A coastal ocean extreme bloom incubator

Author

Ryan, John P., primary, Gower, James F. R., additional, King, Stephanie A., additional, Bissett, W. Paul, additional, Fischer, Andrew M., additional, Kudela, Raphael M., additional, Kolber, Zbigniew, additional, Mazzillo, Fernanda, additional, Rienecker, Erich V., additional, and Chavez, Francisco P., additional

Published
2008
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245. From Wind to Whales: Trophic Links in a Coastal Upwelling System

Author

Benson, Scott., Black, Nancy., Chavez, Francisco P., Croll, Donald A., Marinovic, Baldo., Ternullo, Richard., Tershy, Bernie R., Benson, Scott., Black, Nancy., Chavez, Francisco P., Croll, Donald A., Marinovic, Baldo., Ternullo, Richard., and Tershy, Bernie R.

Abstract

Donald Croll of the University of California at Santa Cruz, and a host of researchers from Moss Landing, California, offer this report on blue whales, with emphasis on whale distribution and abundance, diet and foraging (Euphausiids), migration, and seasonality of whale distribution in relation to diet and oceanographic processes. The document is a final report to the Monterey Bay National Marine Sanctuary.

Published
2000

249. Cyanobacterial distributions along a physico-chemical gradient in the Northeastern Pacific Ocean.

Author

Sudek, Sebastian, Everroad, R. Craig, Gehman, Alyssa ‐ Lois M., Smith, Jason M., Poirier, Camille L., Chavez, Francisco P., and Worden, Alexandra Z.

Subjects
CYANOBACTERIA physiology, GEOGRAPHICAL distribution of bacteria, PRIMARY productivity (Biology), SEAWATER
Abstract

The cyanobacteria P rochlorococcus and S ynechococcus are important marine primary producers. We explored their distributions and covariance along a physico-chemical gradient from coastal to open ocean waters in the Northeastern Pacific Ocean. An inter-annual pattern was delineated in the dynamic transition zone where upwelled and eastern boundary current waters mix, and two new S ynechococcus clades, Eastern Pacific Clade ( EPC) 1 and EPC2, were identified. By applying state-of-the-art phylogenetic analysis tools to bar-coded 16S amplicon datasets, we observed higher abundance of P rochlorococcus high-light I ( HLI) and low-light I ( LLI) in years when more oligotrophic water intruded farther inshore, while under stronger upwelling S ynechococcus I and IV dominated. However, contributions of some cyanobacterial clades were proportionally relatively constant, e.g. S ynechococcus EPC2. In addition to supporting observations that P rochlorococcus LLI thrive at higher irradiances than other LL taxa, the results suggest LLI tolerate lower temperatures than previously reported. The phylogenetic precision of our 16S rRNA gene analytical approach and depth of bar-coded sequencing also facilitated detection of clades at low abundance in unexpected places. These include P rochlorococcus at the coast and C yanobium-related sequences offshore, although it remains unclear whether these came from resident or potentially advected cells. Our study enhances understanding of cyanobacterial distributions in an ecologically important eastern boundary system. [ABSTRACT FROM AUTHOR]

Published
2015
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250. Self-adjusting focus of attention in combination with a genetic fuzzy system for improving a laser environment control device system.

Author

Clemente, Eddie, Chavez, Francisco, Fernandez de Vega, Francisco, and Olague, Gustavo

Subjects
GENETIC algorithms, FUZZY systems, CONTROL theory (Engineering), IMAGE converters, COMPUTER vision
Abstract

This paper presents a new algorithm capable of improving the accuracy level of a laser pointer detector used within an interactive control device system. A genetic programming based approach has been employed to develop a focus of attention algorithm, which works cooperatively with a genetic fuzzy system. The idea is to improve the detection of laser-spots depicted on images captured by video cameras working on home environments. The new and more accurate detection system, in combination with an environment control system, allows to send correct orders to home devices. The algorithm is capable of eradicating false offs, thus preventing devices to autonomously activate/deactivate appliances when orders have not been really signalled by users. Moreover, by adding self-adjusting capabilities with a genetic fuzzy system the computer vision algorithm focuses its attention on a narrower area of the image. Extensive experimental results show that the combination of the focus of attention technique with dynamic thresholding and genetic fuzzy systems improves significantly the accuracy of the laser-spot detection system while maintaining extremely low false off rates in comparison with previous approaches. [ABSTRACT FROM AUTHOR]

Published
2015
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