東南亞地區春季前推軌跡群集分析及氣候影響

A Cluster Analysis of the Springtime Forward Trajectories Arising from Southeast Asia and the Climate Influence

余嘉裕(Jia-Yuh Yu) ； 林能暉(Neng-Huei Lin) ； 謝和修(Ho-Hsiu Hsieh) ； 林宗嵩(Tsung-Sung Lin)

《大氣科學》 36卷4期 (2008/12) Pp. 287-301

摘要

東南亞長久以來就是亞洲最主要的生質燃燒氣膠源區，每年春季在該區所產生的大量煤灰氣膠，不僅對區域空氣品質有顯著衝擊，透過改變大氣輻射平衡，也會影響區域氣候型態。本文利用群集分析法，探討NOAAHYSPLIT模式所計算之長期前推軌跡資料，以瞭解春季期間起源自中南半島生質燃燒氣膠之可能傳輸路徑。本文也採用NCEP/NCAR大氣資料，分析氣候條件如何影響軌跡傳輸路徑。
研究結果發現，起源自中南半島北部地區的軌跡傳輸範圍相當廣泛，除了高緯度地區外，整個東亞幾乎都在其影響範圍內。另一方面，起源自中南半島南部的軌跡傳輸範圍大多侷限在中南半島附近，對中緯度地區影響較小。進一步分析軌跡傳輸路徑和氣候關係也發現，起源自中南半島北部之軌跡傳輸路徑在強聖嬰年時有明顯偏北趨勢，其中菲律賓東方海面出現反氣旋式距平環流是導致聖嬰年春季軌跡傳輸路徑偏北的主因。

關鍵字

生質氣膠 ； 群集分析 ； 前推軌跡線

並列摘要

Southeast Asia has long been recognized as the most important source area of biomass burning aerosols. Each spring, a large amount of soot aerosols are released to the atmosphere that might impact the regional air quality and is capable of altering the climate pattern through changing the atmospheric radiation balance. In this study, the forward trajectories derived from the NOAA HYSPLIT model are used to analyze the probable transport paths of biomass aerosols arising from the Indo-China Peninsula. The NCEP/NCAR atmospheric data is also employed to examine the possible climate influence on the transport paths.
Our results show that trajectories released from the northern part of Indo-China Peninsula are capable of affecting almost the entire East Asia. On the other hand, trajectories released from the southern part of Indo-China Peninsula are likely to impose influence at a regional scale. We also found that paths of trajectories which are released from the northern Indo-China Peninsula tend to shift northward during strong El Nino years. The existence of an anomalous anti-cyclonic circulation to the east of Philippine is shown to be responsible for such change.

並列關鍵字

Biomass aerosol ； Cluster analysis ； Forward trajectory