: For suitable graphical presentation of the climate, it is requisite that the mesoscale climate of a region, as small as 2 or 3 sq km or as large as 10,000 sq km, be described in sufficient detail to distinguish notable differences within the area. To this end, the construction of azimuthal equal-area maps is developed to achieve a high of degree of conformality, as well as accuracy in the relative sizes of terrestrial areas. Polar equal-area world-wide maps have been developed also with the north pole at the center of the maps. In one map the earth's surface is completely represented in a square. In another map the shape permits the optimum use of normal textbook or notebook pages. (Author)

Mapping the Climate.

A model of sulfate aerosol growth, containing homogeneous gas kinetics, particle growth by coagulationand heteromolecular diffusion, and solar radiation effects has been developed to examine the microphysicalmechanisms associated with clear-air transformation of sulfur dioxide to sulfates in the lower atmosphere.Results indicate that the maximum oxidation rate of sulfur dioxide is approximately 1% h and that thesulfate particles produced by clear-air oxidation processes evolve to give a spectrum with an active modeat 0.03 m radius. The oxidation of sulfur dioxide undergoes a diurnal variation in response to the diurnalsolar cycle. The transformation rate of sulfur dioxide increases as atmospheric opacity decreases and thenumber density of sulfate particles increases with increasing atmospheric humidity.

Formation of Sulfate in a Cloud-Free Environment

Built Environment Correlates of Asthma in the Region of Peel

Numerical Analysis of the Diffusion of Inert Air Pollutant in the Flow Field by Jet Engine Exhaust

Numerical studies have been carried out to examine the effects of chemically reactive trace gases emitted into the atmosphere on the evolution of chemical species concentrations, on the chemical composition and size distribution of airborne particles, and on optical properties of aerosols. Argonne`s chemistry module has been modified by refining the treatment of gas-to-particle conversion. The changes in size distribution and chemical composition of aerosols are calculated with consideration of heteramolecular diffusion and coagulation. Results of the 24 h real-time simulation indicate that the maximum oxidation rate of sulfur dioxide is about 0.4% h{sup {minus}1}; that the total aerosol volume increases with the increase in relative humidity by as much as 36% (due mainly to the collection of sulfuric acid embryos by preexisting particles); and that the surface area, a measure of optical depth, increases with the increase in relative humidity by as much as 27%.

The effects of emission of anthropogenic chemical species on chemical and physical properties of aerosols

Results are presented of numerical experiments modeling meteorology, multiple pollutant sources, and nonlinear photochemical reactions for the case of an airport in a large urban area with complex terrain. A planetary boundary-layer model which predicts the mixing depth and generates wind, moisture, and temperature fields was used; it utilizes only surface and synoptic boundary conditions as input data. A version of the Hecht-Seinfeld-Dodge chemical kinetics model is integrated with a new, rapid numerical technique; both the San Francisco Bay Area Air Quality Management District source inventory and the San Jose Airport aircraft inventory are utilized. The air quality model results are presented in contour plots; the combined results illustrate that the highly nonlinear interactions which are present require that the chemistry and meteorology be considered simultaneously to make a valid assessment of the effects of individual sources on regional air quality.

In Young Lee

Papers

Meteorological and Air Pollution Modeling for an Urban Airport.