| 摘要: | 本研究旨在探討背景大氣中氟氯碳化物(chlorofluorocarbons, CFCs)和氟氯氫碳化物(hydrochlorofluorocarbons, HCFCs)的變化與成長趨勢，與評估東亞各地區之排放特徵，並發展相關觀測分析技術，目標物質包含CFC-12、CFC-11、HCFC-22等鹵碳化合物(halocarbons)氣體。蒙特婁協議與其增訂案所規範之物種包括CFCs和HCFCs等物質，具有破壞臭氧層的能力，並為具潛勢之溫室氣體，其濃度的增加將可能對於全球暖化和區域性氣候變遷造成影響。雖已協定不再生產或使用CFCs而使其大氣含量逐年降低，但近年研究指出CFC-11濃度下降速度趨緩，且在某些特定亞洲污染外流事件中和HCFC-22存在高度相關性，推論在東亞地區疑有顯著排放，另因HCFCs廢除期程尚未截滿，導致HCFCs濃度仍持續增加。東亞地區多為開發中國家，仍可能存在不少未查之CFCs和HCFCs排放，台灣位於西太平洋的邊陲極，適合於監測該地區halocarbons的變化特徵。同時，蒙特婁議定書的減量成效須藉由精準的分析技術來評估，是故，有鑒於我國相關監測技術的發展不足 ;This study aims at investigating the characteristics and trends of atmospheric chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) in the East Asia. In order to do so, an integrated monitoring method by gas chromatography will be established and used to measure the background air. The target halocarbons include CFC-12, CFC-11 and HCFC-22, which are restricted by the Montreal Protocol. These compounds can not only harm the ozone layer, but also exhibit with significant radiative forcing resulting in global warming and climate change. Besides their atmospheric variations, the emissions and budget will also be carefully studied based on intensive measurements by using the aforementioned methods to provide the regional view of these species.A recent scientific finding by Dr. Montzka at NOAA/GMD suggested that the decreasing rate of CFC-11 was slowing down after 2012, which could be possibly due to the unreported emissions from the East Asia. To further identify the possible sources of these compounds in the East Asia, measurements can be made to evaluate the emission inventories. Present characteristics and future projections of these compounds can also be performed. To strengthen our understanding of this relatively pristine region receives air masses via long-range transport pathways, multiple sampling locations, e.g. Lulin Atmospheric Background Station (23.47°N, 120.87°E; 2862 m a.s.l.), Kenting (20.05°N, 120.70°E; 8 m a.s.l.), and oversea remote sites such as Mt. Fuji, Yonagunijima, northern Tailand and Vietnam, will be served to investigate the changes and events of atmospheric halocarbons from the perspectives of concentration variations and correlations representative in different countries in the East Asia. |
