Changes in the Relationship between Particulate Matter and Surface Temperature in Seoul from 2002–2017

Minjoong J Kim

doi:10.3390/atmos10050238

Abstract

This study focuses on the changes over time in the relationship between surface temperature and particulate matter (PM) concentration over Seoul using long-term observational data. Correlation coefficients between the daily mean PM10 concentration and surface temperature were calculated to investigate the relationship between the two. The PM10 and temperature displayed a strong positive correlation, suggesting the increase in PM was driven by large-scale synoptic patterns accompanying such high temperatures. It was found that the correlation coefficient in 2002–2009 was significantly higher than that of 2010–2017, indicating that the relationship between PM10 concentration and temperature has weakened over time in recent decades. Correlation coefficients between daily averaged temperature and the PM10 of each year were calculated to account for the decreased correlation in the most recent decade. We found that the correlation coefficients between surface temperature and PM of each year exhibited a clear negative correlation with the longitudinal position of the Siberian High, suggesting that the position of the Siberian High might affect the strength of the relationship between PM concentration and temperature over Seoul. We also found that the eastward shift of the Siberian High reduces the standard deviation of pressure over Seoul, indicating reduction of synoptic perturbation. These results imply that the eastward shift of the Siberian High in recent decades might weaken the relationship between the PM and surface temperature over Seoul. This study suggests that the relationship between PM and meteorological variables is changing over time through changes in large climate variability.

Highlights

Poor air quality as a result of particulate matter (PM) in Seoul, the largest city in South Korea, is a serious issue
Previous studies have suggested that emission changes are the primary factor in determining the PM level over East Asia and Seoul [1,11,12], PM concentration is significantly affected by meteorological conditions, since changes in emissions tend to occur slowly [13]
To prevent the current index being affected by high-pressure areas in the polar or other Asian regions, the spatial domain in which the 1026 hPa isobar was considered for the longitude center of Siberian High calculation was limited

Summary

Introduction

Poor air quality as a result of particulate matter (PM) in Seoul, the largest city in South Korea, is a serious issue. This is exemplified by frequent haze events, which are common in winter [1,2,3]. Previous studies have suggested that emission changes are the primary factor in determining the PM level over East Asia and Seoul [1,11,12], PM concentration is significantly affected by meteorological conditions, since changes in emissions tend to occur slowly [13]. Factors that potentially affect the relationship between PM and temperature are explored by using long-term observational data and a re-analysis dataset

Domain and Data

Multi-year

3.3.Results

Scatterplot of the daily averaged surfacethe

Conclusion