연구보고서
- 저자
- 김선태 박사
- 작성일
- 2019.06.12
- 조회
- 426
- 요약
- 목차
This study presents an analysis of the extreme temperature and precipitation events that occurred in 2018. The extreme hot days and wet days in 2018 increased significantly compared to those during the baseline period (1981–2010) whereas the number of the extreme cold days are within a statistical inter-quantile range over the same period. The regions in North America and east Asia suffered from a record high number of extreme hot days in summer 2018. To understand extreme climate events that are occurring currently, we first analyzed the features of the extreme climate events during the baseline period and found positive trends in the number of the extreme hot days and a negative trend in the number of the extreme cold days. The Northern hemisphere, in particular, had the larger positive trends in extreme hot days; furthermore, the negative trends were larger during the summer-to-fall season than during other seasons. Both of these indicate strong global warming during these seasons. In terms of extreme wet days, positive trends dominate in south and east Asia. We also computed the correlation coefficients between the extreme events and atmospheric and oceanic variables, including sea surface temperature, geopotential height at 500 hPa (Z500), and sea level pressure (SLP) to investigate atmospheric and oceanic circulations associated with extreme events during the baseline period. This information was utilized to reveal the possible dynamics behind the record high increase in extreme hot days in east Asia. It is concluded that this is attributable to positive Z500 anomalies that developed near east Asian region, as during the baseline period, and that the negative Z500 or SLP anomalies that developed in the tropical north Pacific contributed to the enhancement of the positive Z500 anomalies