USDA Forest Service

Pacific Southwest Research Station


Pacific Southwest Research Station
800 Buchanan Street
Albany, CA 94710-0011

(510) 559-6300

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Ozone modeling system and emission control strategies for the Lake Tahoe Basin

Proposal [pdf]

Lead Researchers:

Darko Koracin, Julide Kahyaoglu-Koracin, and Alan Gertler, Desert Research Institute


In the past years there have been an increasing number of exceedances of the California 8-hour ozone standard in the Lake Tahoe Air Basin, and the area is currently designated as a nonattainment-transitional zone for ozone (O3) by the California Air Resources Board. A robust emission control strategy is needed and can only be achieved if we have a detailed understanding of the processes affecting the local and regional O3 formation, transport and dispersion patterns by using measurements and modeling. In response to Subtheme 3b: Managing air pollutants, we propose to: 1) develop, validate, and apply an advanced state-of-the-art emission, atmospheric, and photochemical modeling system (SMOKE/WRF/CMAQ) to simulate ozone in the Lake Tahoe Basin using local emission inventory and CARB and EPA emission inventories, 2) validate the ozone modeling system using exceedance episodes in the period 2006-2009 as well as against recent measurements in summer 2010, 3) integrate the ozone modeling system as a component of the Lake Tahoe Air Quality Modeling System (LTAQMS), and 4) perform simulations for various emission scenarios and determine the most cost effective control strategies for the basin emission sources to control ozone levels. The study will also provide quantification of the impact of local vs. regional sources of ozone and its precursors.

Relation to Other Research Including SNPLMA Science Projects

The proposed study builds upon a number of previous programs conducted in the basin (Gertler et al., 2006; Kahyaoglu-Koracin et al., 2004, 2005, 2008; Bytnerowicz et al., 2004, Dolislager et al., 2009). These studies concluded that most of the pollutants in the basin are locally emitted and O3 transport into the Lake Tahoe Basin is limited. However, the study by Dolislager et al. (2009) also indicated that under certain circumstances transported O3 may occur and lead to elevated O3 levels. For the highest-resolution grid centered at Lake Tahoe, we will use the emission inventory developed by Gertler, Weinroth, Luria, and Kahyaoglu-Koracin (2008). This will provide the most up-to-date emissions inventory for the basin, including biogenic organic species, which is critical in terms of ozone prediction in a photochemical modeling study. In addition, chemical and meteorological data collected under previous and current studies will provide much of the information required to run the modeling system. This project also builds upon research efforts funded in SNPLMA Round 10, "Distribution of ozone, ozone precursors and gaseous components of atmospheric deposition in the Lake Tahoe Basin," and Round 11, "Secondary pollutant formation in the Lake Tahoe Basin."

Expected date of final products:

October 2013

Last Modified: Mar 28, 2013 02:52:08 PM