A spatially and temporally resolved biogenic hydrocarbon emissions inventory for the California South Coast Air Basin

Natural emissions of non-methane volatile organic compounds, carbon monoxide, and oxides of nitrogen from North America

“…These errors probably have a small impact on seasonal and annual estimates but could be important for investigations of speci"c scenarios. Benjamin et al (1997) found that the elevation gradients in the California south coast basin result in ambient temperature di!erences of over 203C within this region. Solar radiation #uxes can also vary considerably on this spatial scale due to the presence of clouds.…”

“…Suitable landcover data are also lacking in most urban areas. Improved urban landcover characterization requires a signi"cant e!ort focusing on a speci"c location (e.g., Benjamin et al, 1997). The potential for high NMVOC from grasses, particularly mown lawns (De Gouw et al, 1999), indicates that urban vegetation surveys, which sometimes include only woody plants, should be expanded.…”

“…If growth environment and leaf age are nearly constant, then leaf-to-leaf variability is about 5% for a single tree , 10% for di!erent trees of the same clone (Isebrands et al, 1999), and about 25% for di!erent clones of the same genus (Isebrands et al, 1999). Benjamin et al (1996Benjamin et al ( ,1997 assigned di!erent isoprene emission capacities to a large number of plant species. Some oaks were assigned moderately high isoprene emission capacities, e.g., 59.2 g g\ h\ for Q. garryana and 76.6 g g\ h\ for Q. robur, while other oaks were assigned much lower rates, e.g., 3.4 g g\ h\ for Q. lobata and 8.7 g g\ h\ for Q. douglasii.…”

Weekday versus Weekend Activity Patterns for Ozone Precursor Emissions in California’s South Coast Air Basin

“…Total emissions by source category and pollutant are presented in Table 1. 22,23 Based on these values, on-road mobile sources constitute the single largest source category for O 3 precursor pollutants, accounting for 49, 62, and 80% of average daily reactive organic gases (ROGs), NO x , and CO, respectively, in the SoCAB. Most on-road emissions originate from gasoline vehicles; diesel vehicles contribute approximately 27% of total NO x emissions.…”

Effects of different doses of nitrogen treatments on isoprene emission from Ficus glomerata

“…In the atmosphere, isoprene rapidly reacts with nitrogen oxides (NOx), hydroxyl radicals, NO 3 , and ozone and produces a wide range of compounds including carbonyls, organic acids, ozone, CO and aerosols (Zimmerman et al, 1978;Jacob and Wofsy, 1988 and;Chameides et al, 1992). It has been reported that isoprene emission is species specific varying as much as four order of magnitude depending upon plant species (Benjamin et al, 1996). Various studies have shown that isoprene emission from vegetation is influenced by temperature (Tingey et al, 1979), solar radiation (Harley et al, 1996), season (Singh et al, 2008) and soil nitrogen level .…”