Trend analysis of air quality variation in Hualien, Taiwan, during 2005 - 2017

• Main Authors: HOU,YOU-LIN, 侯宥琳
• Other Authors: HSU,WEN-CHANG
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/u34hp9

碩士 === 大漢技術學院 === 土木工程與環境資源管理研究所 === 106 === Abstract In this study, data collected from Dahan Institute of Technology’s (Dahan Station) manual method PM2.5 air quality monitoring station. According to Taiwan Environmental Protection Administration’s (TEPA) automatic method revise PM2.5 air quality monitoring in Hualien Station from 2005 to 2013. The objective of this study is trend analysis of air quality variation and Air Quality Index (AQI) indicators in Hualien area in the past 13 years. First, recalculate AQI data in Hualien Station from 2005 to 2017. Then, sources of air currents simulated with backward trajectory models. Finally, explore the changes of AQI values and indicators of pollutants in the Hualien area under the influence of different airflow sources. The results of this study manual measurement method of Dahan Station were used to correct the automatic measurement of PM2.5 in Hualien Station. The value from 2009 to 2013 was between 0.75 ~0.89 and the regression analysis of the TEPA from 2014 to 2018 slope value 0.77~ 0.81, compared without difference. The correction of PM2.5 automatic measurement should have certain credibility.However, the Hualien Area from 2005 to 2017 without affecting the influence of airflow the average annual AQI value is 53.The firstly, measured under the influence of the northeast monsoon the annual average AQI value is the highest 58, which is 1.9 times the annual average. Secondly, the measured under the influence of high pressure reflow the annual average AQI value is 57, which is 1.7 times the annual average. Thirdly, the measured under the influence of the southwesterly airflow the annual average AQI value is 50, which is 0.94 times the annual average. Fourthly, the measured under the influence of Pacific high pressure the annual average AQI value is the lowest 38, which is 0.72 times the annual average. Among them, the measured under the influence of China the annual average AQI value is as high as 68, which is 1.28 times of the annual average. It is show that the pollutants from the mainland of China are the main factors causing the deterioration of air quality in Hualien Area. The analysis results of the AQI sub-indicators from 2005 to 2017 show that influence the mainly pollutant is PM2.5 and O3 in Hualien area. The trend analysis of the AQI sub-indicators average value shows that the PM2.5 sub-indicator shows a significant downward trend, while the O3, 8hrs has an upward trend year by year. The results obtained measured under the influence of the each type of northeast monsoon the average AQI value is the highest 69±11 of A2 type.The measured under the influence of the each type of high pressure reflow the average AQI value is the highest 73±13 of the B2 type. This finding suggests that the each sub-category AQI shows a downward trend year by year.The AQI values measured by the airflow patterns (A0, A1, A2, and B2) originating in mainland China are higher than anothers,indicating that the pollutants transmitted from China will dominate the air quality in Hualien. Trend analysis of the past 13 years ,the AQI measured by various subdivision types in China showed a downward trend,and the decrease of PM2.5 sub-indicator was the most significant, so PM2.5 was the indicator pollutant.This indicates that the pollution of PM2.5 transmitted from outside the China has been significantly reduced in recent years. This is the mainly reason for the better air quality in Hualien. In summary, the control of PM2.5 pollution has achieved certain results, but the pollution of O3 has a trend of increasing severity. The trend analysis shows that the PM2.5 sub-indicator value and the O3 sub-indicator value cross in 2017. The air quality of Hualien area may be impacted significantly by O3 in the future will become increasingly important and worthy of attention.