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An inventory of volatile organic compound (VOC) and nitrogen oxides (NOx) emissions is an important tool for the management of ground-level ozone pollution. This paper has two broad aims: it illustrates the potential of a geographic information system (GIS) for enhancing an existing spatially-aggregated, anthropogenic emissions inventory (EI) for Tucson,(More)
A limited number of sample points greatly reduces the availability of appropriate spatial interpolation methods. This is a common problem when one attempts to accurately predict air pollution levels across a metropolitan area. Using ground-level ozone concentrations in the Tucson, Arizona, region as an example, this paper discusses the above problem and its(More)
This article addresses the need to better understand the complex interactions between climate, human activities, vegetation responses, and surface ozone so that more informed air-quality policy recommendations can be made. The impacts of intraseasonal climate variations on ozone levels in Tucson, Arizona from April through September of 1995 to 1998 are(More)
This paper examines di!erences between daily maximum weekday and weekend ambient ozone concentrations in the Tucson, AZ metropolitan area. Temporal variations in the Weekend E!ect (i.e. weekend ozone concentrations are larger than weekday concentrations) are not explained entirely by changes in anthropogenic emissions of ozone precursor chemicals (i.e.(More)
Past climatological research has not quantitatively defined the synoptic-scale circulation deviations responsible for anomalous summer-season precipitation totals in the southeastern United States. Therefore, the objectives of this research were to determine the synoptic-scale controls of wet and dry multiday periods during the summer within a portion of(More)
Following the establishment of point measurements of ground-level ozone concentrations have been attempts by many researchers to develop ozone surfaces. This paper offers a critique of ozone-mapping endeavors, while also empirically exploring the operational scale of ground-level ozone. The following issues are discussed: aspects of spatial scale; the(More)
This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values(More)
Central equatorial Africa is deficient in long-term, ground-based measurements of rainfall; therefore, the aim of this study is to assess the accuracy of three high-resolution, satellite-based rainfall products in western Uganda for the 2001–10 period. The three products are African Rainfall Climatology, version 2 (ARC2); African Rainfall Estimation(More)
Through modification of the planetary boundary layer, urbanization has the potential to have a significant impact on precipitation totals locally. Using daily summer-season precipitation data at 30 stations from 1953 to 2002, this study explores the possibility of urban effects as causes of spatial anomalies in precipitation in a zone within 180 km of(More)
This article explores the possibility of urbanization-and irrigation-induced increases in summer precipitation totals in central Arizona. Maximum precipitation impacts are hypothesized to occur downwind of the Phoenix area in the Lower Verde basin. Results from statistical tests indicate that summer precipitation totals in the Lower Verde basin are greater(More)