A modelling study of assessment of the effectiveness of combining foreign and local emission control strategies

摘要

In order to improve the atmospheric PM2.5 levels of Taiwan, the Taiwanese government has developed a number of detailed emission reduction measures based on a highly detailed emission database, hoping to meet stringent air quality standards (15 mu g/m(3)) by 2020. Past studies have shown that Chinese pollutants have a significant impact on Taiwanese air quality; fortunately, China has also been actively promoting various emission control. This study used an air quality model to simulate and evaluate improvements under three emission control scenarios, and assessed the possibility of achieving governmental air quality standards across the various regions of Taiwan under these scenarios. The simulation results show that under the implementation of the expected Taiwan and China emission control strategies (Scenario 3), all regions in Taiwan can reach the 1-Hour O-3 standard (120 ppb) by 2020, but since the 8-Hour O-3 standard (60 ppb) is considerably stricter, with strategies biased toward PM2.5 improvement, most areas, particularly western Taiwan, will still be unable to meet the standards by 2020. For PM2.5, regulatory responses have significantly improved Annual PM(2.5 )and 24-Hour PM(2.5 )in each region, especially in southern Taiwan, however in most regions such as western Taiwan there are still pockets of pollutants where Annual PM2.5 (15 mu g/m(3)) and 24 Hour PM2.5 (35 mu g/m(3)) rise well above the desired threshold to 2-14 mu g/m(3) and 3-30 mu g/m(3) respectively. It is suggested that Taiwan should propose more intensive emission control measures and strengthen the implementation of such measures. This will be required in addition to the continued emission reductions policy currently in place in domestic China.