| 摘要: | 東亞與東南亞是最主要的大氣汞排放源區，貢獻約40%的全球人為大氣汞排放量，而中國人為排放量約占全球排放量的30%，高居世界第一。此外，生質燃燒也是重要大氣汞排放源，而中南半島與印尼是生質燃燒活動旺盛區域，合計約貢獻37%的全球生質燃燒大氣汞排放量，我國鹿林山測站長期觀測資料即顯示，每年3-4月中南半島生質燃燒排放之污染物可隨高層西風傳送至我國高山地區，導致大氣污染物(如一氧化碳、臭氧、懸浮微粒、大氣汞)濃度升高。近年來中國大規模霧霾事件發生頻繁，跨境傳輸影響台灣，也可伴隨著大氣汞輸入，曾導致中央大學校園氣態元素汞濃度增加1-1.5倍，而顆粒汞濃度更是增加3.8-14.4倍。因此，區域大氣汞排放對東亞、東南亞、南海及西北太平洋空氣品質、環境生態以及人體健康的影響應詳細調查與評估。本研究將配合總計畫規劃期程與工作，進行區域國際合作，參與國際觀測實驗，於東南亞生質燃燒期間(如春季中南半島或是夏、秋季印尼)或是東北季風盛行與中國霧霾事件好發季節(秋、冬、春季)，在發生源區(如泰國、越南、印尼或菲律賓)或下風處受體區(如我國太平島、東沙島、富貴角、竹子山、中壢、鹿林山或恆春等)測站，進行大氣汞濃度與物種組成觀測，以及顆粒汞分徑觀測，並與氣象、大氣輻射、其他大氣污染物觀測資料及區域模式整合，特徵化不同型態區域大氣污染物傳輸事件所對應之大氣汞物種組成與分布，研究傳輸過程中之物理與化學行為，研析跨境大氣汞傳輸對於我國的影響，並探討區域大氣汞循環。 ;East and Southeast Asia is the major atmospheric mercury (Hg) emission source region, contributing about 40% of the global anthropogenic Hg emissions. China alone contributed about 30% of the global emission, making it the top emitter worldwide. Biomass burning also has been identified as an important emission source of atmospheric Hg. Indonesia and the Indochina Peninsula are major biomass burning regions that contributed about 37% of the global biomass burning Hg emissions. Long-term monitoring results of air pollutants at Lulin Atmospheric Background Station (LABS) have demonstrated the influences of springtime (March-April) biomass burning activities in the Indochina Peninsula on the air quality of high mountains in Taiwan, resulting in elevated concentrations of CO, O3, aerosols, and Hg. In recent years, the frequent occurrence of haze over east and north China has raised concerns over its impacts on visibility, air quality, and human health. Haze events are characterized by poor air circulation and high concentrations of fine particles, which can affect the concentration, speciation, and chemistry of atmospheric Hg. For example, concentrations of gaseous elemental Hg (GEM) and particle-bound Hg (PBM) showed enhancements of 100-147% and 378-1438%, respectively, during trans-boundary haze events. Therefore, influences of regional atmospheric Hg emissions on air quality, ecosystem, and human health in East and Southeast Asia, South China Sea, and Northwest Pacific Ocean should be investigated and assessed. This research project is hence proposed to characterize atmospheric Hg speciation and distribution with different regional pollutant transport types, to study the physical and chemical transformation of Hg speciation during transport, to study the influence of trans-boundary transported atmospheric Hg on Taiwan, and to discuss the regional atmospheric Hg cycle. Via regional international collaboration, measurements of atmospheric Hg and particle size-segregated PBM will be conducted at sites in the source region (Thailand, Vietnam, Indonesia or the Philippines) or the downwind receptor sites in Taiwan (such as Taiping Island, Dongsha Island, Cape Fuguei, Mt. Bamboo, Jhongli, Mt. Lulin, or Hengchun). Meteorological information and data of atmospheric radiation and other air pollutants will be integrated with the Hg data for detail analyses and discussion. |
