Impacts of Emissions Changes from the Transportation Sector on Future U.S. Air Quality

摘要

The implemented emissions growth factors project global transportation emissions to decrease by 2030, and then increase by 2050. The near-term decrease is due to the implementation of more stringent emissions standards in the near-term, particularly for on-road vehicles. The increase by 2050 coincides with large growth in on-road vehicle emissions in developing countries in Africa, increased non-road engine emissions, increased fuel consumption, and a larger contribution from shipping emissions by 2050. The best performing WRF model configuration is statistically determined through repeated sensitivity tests, and is then used for the baseline 2005 WRF_NCEP simulation. Meteorological evaluation of this simulation indicates statistics near or within acceptable criteria, thus establishing the 2005 baseline meteorology. Meteorological evaluation of a 2005 WRFCCSM simulation indicates statistics outside the acceptable limits, and thus further work is needed to correct the CCSM ICONs and BCONs prior to CMAQ simulations for the current and future years. A preliminary chemical evaluation of the 2005 CMAQ test simulation driven by.WRFNCEP indicates improved statistical performance compared to past coupled CMAQ simulations, and thus there is confidence to use such a configuration for the current and future-year CMAQ simulations, which are currently underway.