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Example results of ozone simulations based on CMAQ model driven by urbanized (UCP) versus standard version (no UCP) of MM5 at 1-km grid size for Houston, TX, at 2100 UTC 30 Aug 2000.

Example results of ozone simulations based on CMAQ model driven by urbanized (UCP) versus standard version (no UCP) of MM5 at 1-km grid size for Houston, TX, at 2100 UTC 30 Aug 2000.

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Based on the need for advanced treatments of high-resolution urban morphological features (e. g., buildings and trees) in meteorological, dispersion, air quality, and human-exposure modeling systems for future urban applications, a new project was launched called the National Urban Database and Access Portal Tool (NUDAPT). NUDAPT is sponsored by th...

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... in the metropolitan area of Houston are negligible in the standard implementation in contrast to results from the urbanized version. Both sets of meteorology were used to simulate air quality using the U.S.EPA's CMAQ modeling system (By un and Schere 2006); the results exhibited significant differences in magnitude and spatial patterns for ozone (Fig. 7). These simulations show the effect of ozone titration by elevated levels of nitrogen oxide (NO x ), primarily from mobile source contributions. (Simulations performed at 4-km grid size exhibited considerably reduced levels of NO x and a concomitant reduction in titration effects on ozone.) Sensitivity studies using urbanized WRF. The ...

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