多元空氣品質指標 (RAQI) 應用之探討

A Revised Air Quality Index Based on a Multi-Pollutant with an Entropy Function

林佐美(Tso-Mei Lin) ； 陳育松(Yu-Song Chen) ； 郭育誌(Yu-Chih Kuo) ； 程萬里(Wan-Li Cheng)

《東海科學》 5期 (2003/07) Pp. 1-20

摘要

本研究以熵函數（entropy function）概念研發出修正現行空氣品質指標之RAQI（Revised Air Quality Index, RAQI），以結合函數（aggregating function）計算選取指標值及增訂指標等級分級，改善現行污染物標準指標（Pollutant Standards Index, PSI）之選取副指標值最大值作為當日之PSI指標，以及PSI值大於100定義為空氣品質不良，但其污染物濃度之換算值卻與空氣品質標準與發布各級空氣品質惡化警告之污染物濃度條件有所差異，容易造成認知上誤解之情形。
研究結果顯示，以1999年至2000年之中部空品區及高屏空品區為例，RAQI與現行PSI差異性顯著，並於高污染之情況下產生空氣品質指標值差異分歧；另一方面運用RAQI於中部空品區及高屏空品區都會區測站上，比較結果發現RAQI與PSI之指標值各區段日數分布情況有所差異，RAQI指標值較為擴散並且涵蓋範圍加大，有助於反應高污染事件日之空氣品質。由於RAQI結合五種副指標污染物(PM10、SO2、CO、NO2及O3)之資訊及完善空氣品質等級分級，較具客觀及充分的代表性，供未來空氣品質指標的評估及修訂參考。

關鍵字

污染物標準指標 ； 熵函數' ； 修正現行之空氣品質指標

並列摘要

This study is based on the entropy function amending the current air quality index in order to create a Revised Air Quality Index (RAQI). By combining the RAQI and aggregation function, the current Pollutant Standards Index (PSI) is calculated by amending the index value and adding the index level. The greatest value of the sub index is the PSI value on the day. When the PSI value reaches 100, the region may be regarded as polluted. Therefore, this transformation could be misleading, and the confusion is further increased as the standard pollution concentration level varies among different countries.
As a result, it shows that the distribution of index value of RAQI and current PSI are diverse, especially in the high pollution episode of the Kaoping Air Quality Region and Taichung Air Quality Region in the years 1999 and 2000. Also, the daily distribution of index value of RAQI and PSI are different. The RAQI value is more diffused and contains a larger area which conduces to show the air quality in a high pollution episode. From our research, air quality in the Kaoping Air Quality Region and the Taichung Air Quality Region are mainly affected by PM10 and O3, and air quality in the former region is more serious than in the latter. Information from five sub index pollutants (PM10, O3, SO2, CO, NO2) and RAQI can present a local scale environment and offer the effective assessment.

並列關鍵字

Pollutants Standard Index ； entropy function ； Revised Air Quality Index