우리나라 지역별 초미세먼지(PM_2.5) 농도 추이와 고농도 발생 현황

Trends of the PM_2.5 concentrations and high PM_2.5 concentration cases by region in Korea

Abstract

The public's concern on ambient $PM_{2.5}$ has been increasing in Korea. We have estimated (1) the annual and monthly mean $PM_{2.5}$ concentrations, (2) the frequency by the $PM_{2.5}$ concentration interval, and (3) the high concentration occurrence duration time between 2015 and 2018 at 16 administration regions. We found that there have been differences in all three above parameters' trends among the studied 16 regions in Korea. Still, Jeonbuk showed the highest rank in all three parameters' trends. In Jeonbuk, the average $PM_{2.5}$ concentration and the sum of the frequency fraction when the $PM_{2.5}$ concentration being over $75{\mu}g/m^3$ between 2016 and 2018 was $28.4{\mu}g/m^3$ and 9.0%, respectively. And the days when the $PM_{2.5}$ concentration is over $50{\mu}g/m^3$ between 2015 and 2018 were 149. Chungbuk was the only region with the increasing trend of $PM_{2.5}$ concentration between 2016 and 2018. And in Seoul and Gyeonggi, the average $PM_{2.5}$ concentrations decreased whereas the high concentration frequency fraction increased between 2016 and 2018. Also, it is found that there have been differences in the trends of the frequency by the $PM_{2.5}$ concentration interval and the high concentration occurrence duration time between $PM_{10}$ and $PM_{2.5}$.

Fig. 1. Annual mean PM_2.5 concentration (first bold line with circle markers) and annual PM_2.5 frequency fraction by the concentration level in each region, respectively (second and third bold lines (dark), and fourth line (light) for PM_2.5: > 35, > 50, and > 75 ㎍/㎥) (raw data: KECO, 2019)

Fig. 2. Quartile and average trends of PM_2.5 concentration by region between 2015 and 2018 (raw data: KECO, 2019).

Fig. 3. Monthly mean PM_2.5 concentration (first bold line with circle markers) and PM_2.5 frequency fraction by the concentration level in each region, respectively (second and third bold lines (dark), and fourth line (light) for PM_2.5: > 35, > 50, and > 75㎍ /㎥) (raw data: KECO, 2019).

Fig. 4. Annual frequency over 50 ㎍ /㎥ for duration for PM_2.5 (durations: between over 2 and 10 days, respectively) between 2015 and 2018 (raw data: KECO, 2019).

Table 1. Criteria for PM_2.5 levels (re-citation Yeo and Kim, 2019).

Table 2. Annual frequency of the number of days with the PM_2.5 level over 50 ㎍/㎥ by region. Values more than 30 are shaded darker and less than 10 are shaded. Maximum values between 2015 and 2018 by region are in red, respectively. (raw data: KECO, 2019).