scholarly journals Sources of Airborne Ultrafine Particle Number and Mass Concentrations in California

2018 ◽  
Author(s):  
Xin Yu ◽  
Melissa Venecek ◽  
Jianlin Hu ◽  
Saffet Tanrikulu ◽  
Su-Tzai Soon ◽  
...  
Keyword(s):  
Los Angeles ◽  
San Francisco ◽  
Particle Number ◽  
San Francisco Bay Area ◽  
Ultrafine Particle ◽  
Bay Area ◽  
Source Contributions ◽  
Performance Statistics ◽  
South Coast Air Basin ◽  
Daily Time

Abstract. Regional concentrations and source contributions are calculated for airborne particle number concentration (PNC) and ultrafine particle mass concentration (PM0.1) in the San Francisco Bay Area (SFBA) and the South Coast Air Basin (SoCAB) surrounding Los Angeles with 4 km spatial resolution and daily time resolution for selected months in the years 2012, 2015, and 2016. Performance statistics for daily predictions of PNC concentrations meet the threshold normally required for regulatory modeling of PM2.5 (MFB 

scholarly journals Regional sources of airborne ultrafine particle number and mass concentrations in California

2019 ◽  
Vol 19 (23) ◽  
pp. 14677-14702 ◽  
Author(s):  
Xin Yu ◽  
Melissa Venecek ◽  
Anikender Kumar ◽  
Jianlin Hu ◽  
Saffet Tanrikulu ◽  
...  
Keyword(s):  
Los Angeles ◽  
Natural Gas ◽  
San Francisco ◽  
Particle Number ◽  
Ultrafine Particle ◽  
Gas Combustion ◽  
Study Region ◽  
Mobile Sources ◽  
Source Contributions ◽  
Natural Gas Combustion

Abstract. Regional concentrations and source contributions are calculated for airborne particle number concentration (Nx) and ultrafine particle mass concentration (PM0.1) in the San Francisco Bay Area (SFBA) and the South Coast Air Basin (SoCAB) surrounding Los Angeles with 4 km spatial resolution and daily time resolution for selected months in the years 2012, 2015, and 2016. Performance statistics for daily predictions of N10 concentrations meet the goals typically used for modeling of PM2.5 (mean fractional bias (MFB) < ±0.5 and mean fractional error (MFE) < 0.75). The relative ranking and concentration range of source contributions to PM0.1 predicted by regional calculations agree with results from receptor-based studies that use molecular markers for source apportionment at four locations in California. Different sources dominated regional concentrations of N10 and PM0.1 because of the different emitted particle size distributions and different choices for heating fuels. Nucleation (24 %–57 %) made the largest single contribution to N10 concentrations at the 10 regional monitoring locations, followed by natural gas combustion (28 %–45 %), aircraft (2 %–10 %), mobile sources (1 %–5 %), food cooking (1 %–2 %), and wood smoke (0 %–1 %). In contrast, natural gas combustion (22 %–52 %) was the largest source of PM0.1 followed by mobile sources (15 %–42 %), food cooking (4 %–14 %), wood combustion (1 %–12 %), and aircraft (2 %–6 %). The study region encompassed in this project is home to more than 25 million residents, which should provide sufficient power for future epidemiological studies on the health effects of airborne ultrafine particles. All of the PM0.1 and N10 outdoor exposure fields produced in the current study are available free of charge at http://webwolf.engr.ucdavis.edu/data/soa_v3/hourly_avg/ (last access: 20 November 2019).

The “Japanese Turn” in Fine Dining in the United States, 1980–2020

2020 ◽  
Vol 20 (2) ◽  
pp. 45-54
Author(s):  
Samuel H. Yamashita
Keyword(s):  
United States ◽  
New York ◽  
Los Angeles ◽  
San Francisco ◽  
San Francisco Bay Area ◽  
The United States ◽  
First Century ◽  
Further Training ◽  
Bay Area ◽  
Wide Acceptance

In the 1970s, Japanese cooks began to appear in the kitchens of nouvelle cuisine chefs in France for further training, with scores more arriving in the next decades. Paul Bocuse, Alain Chapel, Joël Robuchon, and other leading French chefs started visiting Japan to teach, cook, and sample Japanese cuisine, and ten of them eventually opened restaurants there. In the 1980s and 1990s, these chefs' frequent visits to Japan and the steady flow of Japanese stagiaires to French restaurants in Europe and the United States encouraged a series of changes that I am calling the “Japanese turn,” which found chefs at fine-dining establishments in Los Angeles, New York City, and later the San Francisco Bay Area using an ever-widening array of Japanese ingredients, employing Japanese culinary techniques, and adding Japanese dishes to their menus. By the second decade of the twenty-first century, the wide acceptance of not only Japanese ingredients and techniques but also concepts like umami (savory tastiness) and shun (seasonality) suggest that Japanese cuisine is now well known to many American chefs.

scholarly journals Climate impact on airborne particulate matter concentrations in California using seven year analysis periods

2010 ◽  
Vol 10 (22) ◽  
pp. 11097-11114 ◽  
Author(s):  
A. Mahmud ◽  
M. Hixson ◽  
J. Hu ◽  
Z. Zhao ◽  
S.-H. Chen ◽  
...  
Keyword(s):  
Climate Change ◽  
Air Quality ◽  
Los Angeles ◽  
San Francisco ◽  
San Francisco Bay Area ◽  
Quality Analysis ◽  
Present Climate ◽  
Annual Average ◽  
Bay Area ◽  
Starting Point

Abstract. The effect of global climate change on the annual average concentration of fine particulate matter (PM2.5) in California was studied using a climate-air quality modeling system composed of global through regional models. Output from the NCAR/DOE Parallel Climate Model (PCM) generated under the "business as usual" global emissions scenario was downscaled using the Weather Research and Forecasting (WRF) model followed by air quality simulations using the UCD/CIT airshed model. The system represents major atmospheric processes acting on gas and particle phase species including meteorological effects on emissions, advection, dispersion, chemical reaction rates, gas-particle conversion, and dry/wet deposition. The air quality simulations were carried out for the entire state of California with a resolution of 8-km for the years 2000–2006 (present climate with present emissions) and 2047–2053 (future climate with present emissions). Each of these 7-year analysis periods was analyzed using a total of 1008 simulated days to span a climatologically relevant time period with a practical computational burden. The 7-year windows were chosen to properly account for annual variability with the added benefit that the air quality predictions under the present climate could be compared to actual measurements. The climate-air quality modeling system successfully predicted the spatial pattern of present climate PM2.5 concentrations in California but the absolute magnitude of the annual average PM2.5 concentrations were under-predicted by ~4–39% in the major air basins. The majority of this under-prediction was caused by excess ventilation predicted by PCM-WRF that should be present to the same degree in the current and future time periods so that the net bias introduced into the comparison is minimized. Surface temperature, relative humidity (RH), rain rate, and wind speed were predicted to increase in the future climate while the ultra violet (UV) radiation was predicted to decrease in major urban areas in the San Joaquin Valley (SJV) and South Coast Air Basin (SoCAB). These changes lead to a predicted decrease in PM2.5 mass concentrations of ~0.3–0.7 μg m−3 in the southern portion of the SJV and ~0.3–1.1 μg m−3 along coastal regions of California including the heavily populated San Francisco Bay Area and the SoCAB surrounding Los Angeles. Annual average PM2.5 concentrations were predicted to increase at certain locations within the SJV and the Sacramento Valley (SV) due to the effects of climate change, but a corresponding analysis of the annual variability showed that these predictions are not statistically significant (i.e. the choice of a different 7-year period could produce a different outcome for these regions). Overall, virtually no region in California outside of coastal + central Los Angeles, and a small region around the port of Oakland in the San Francisco Bay Area experienced a statistically significant change in annual average PM2.5 concentrations due to the effects of climate change in the present~study. The present study employs the highest spatial resolution (8 km) and the longest analysis windows (7 years) of any climate-air quality analysis conducted for California to date, but the results still have some degree of uncertainty. Most significantly, GCM calculations have inherent uncertainty that is not fully represented in the current study since a single GCM was used as the starting point for all calculations. The PCM results used in the current study predicted greater wintertime increases in air temperature over the Pacific Ocean than over land, further motivating comparison to other GCM results. Ensembles of GCM results are usually employed to build confidence in climate calculations. The current results provide a first data-point for the climate-air quality analysis that simultaneously employ the fine spatial resolution and long time scales needed to capture the behavior of climate-PM2.5 interactions in California. Future downscaling studies should follow up with a full ensemble of GCMs as their starting point, and include aerosol feedback effects on local meteorology.

Environmental Inequality and the Urbanization of West Coast Watersheds

2006 ◽  
Vol 75 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Sarah S. Elkind
Keyword(s):  
Native Americans ◽  
Los Angeles ◽  
San Francisco ◽  
Industrial Development ◽  
Hispanic Americans ◽  
San Francisco Bay Area ◽  
The United States ◽  
Environmental Racism ◽  
Bay Area ◽  
Access To Water

In the San Francisco Bay Area, Seattle, and Los Angeles, urban development decreased the poor's access to water and marine resources. Modernization in these cities either reduced services to the poor and to ethnic minorities, be they Native Americans,Asian Americans, or Hispanic Americans, or diminished these groups' ability to supplement their incomes by fishing or foraging. Industrial development, shipping channels, and sewers all contributed to a larger pattern of environmental racism and environmental inequity in the United States. This forum contributes to the study of environmental justice by exploring how marginalized peoples adapted to urban growth and the reallocation of resources in the late nineteenth and early twentieth centuries.

Fine and ultrafine particle exposures on 73 trips by car to 65 non-smoking restaurants in the San Francisco Bay Area

Indoor Air ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 205-217 ◽  
Author(s):  
W. R. Ott ◽  
L. A. Wallace ◽  
J. M. McAteer ◽  
L. M. Hildemann
Keyword(s):  
San Francisco ◽  
San Francisco Bay ◽  
San Francisco Bay Area ◽  
Ultrafine Particle ◽  
Bay Area

PLANNING FOR MINIMUM OIL-SPILL RISK: ESTERO BAY DEEPWATER TERMINAL AND PIPELINE

1975 ◽  
Vol 1975 (1) ◽  
pp. 287-291
Author(s):  
Jules F. Mayer
Keyword(s):  
United States ◽  
Los Angeles ◽  
Crude Oil ◽  
San Francisco ◽  
Oil Spill ◽  
San Francisco Bay Area ◽  
Single Point ◽  
The United States ◽  
Bay Area ◽  
Equal Consideration

ABSTRACT Estero Bay, California, located midway between San Francisco and Los Angeles, may be the site of the first deepwater terminal in the United States capable of handling tankers larger than 200,000 deadweight tons. The ships would be moored 2.6 miles from shore at a single point mooring (SPM). Crude oil would be transferred to the San Francisco Bay area by a 280-mile pipeline. One of the first questions asked by most permitting organizations is, what is the chance of an oil spill and how would you clean it up. The environmental studies for the project have addressed this question with particular attention to the prevention of spillage and, secondarily, to the cleanup equipment and organization required in the event that spillage should occur. Equal consideration is being given to the operational procedures, including use of owner-trained mooring masters. A plan for manpower organization and the pooling of people during an emergency has been developed.

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