CCMI 모형에서 성층권 오존의 변화가 남반구 순환 변화에 미치는 영향

학위논문 (석사) -- 서울대학교 대학원 : 자연과학대학 협동과정 계산과학전공, 2020. 8. 손석우.We examine the impacts of stratospheric ozone on Southern Hemisphere (SH) zonal mean circulation changes in state-of-the-art chemistry-climate models from Chemistry-Climate Model Initiative (CCMI) project. First, we evaluate total column ozone (TCO) and ozone depletion induced tropospheric circulation changes in the CCMI. Most models successfully reproduce observation and reanalysis data in the late 20th century. Ozone-hole-induced changes are also robust regardless of the specific chemical-atmosphere-ocean coupling. Since greenhouse gases (GHG) also affect SH circulation changes, the relative importance of ozone and GHG are investigated by examining the single forcing experiments from the CCMI. In particular, the fixed ozone-depleting substance (ODS) simulations, and the fixed GHG simulations are directly compared with the reference simulations for both the past and future. Consistent with previous studies, the SH-summer general circulation changes, such as changes in the jet location, Hadley cell edge, and Southern Annular Mode, show opposite trends from the past to the future in response to the Antarctic ozone depletion and recovery. The GHG-induced circulation changes enhance the ozone-induced circulation changes in the past, but partly cancel them in the future. These results suggest that stratospheric ozone is the primary driver of the SH circulation changes in the past. However, both stratospheric ozone and greenhouse gas are the major factors influencing the SH circulation in the future climate, confirming previous studies.최신 대기화학 모형인 CCMI 모형을 사용하여 오존과 온실기체가 남반구 대기 대순환에 미치는 영향을 분석하였다. 대부분의 CCMI 모형은 과거 오존 전량과 남반구 동서평균 순환을 관측과 유사하게 모의하였다. 과거 남반구 순환의 변화는 모형의 경계조건과 오존의 접합방법에 민감하지 않았다. 온실기체도 남반구 순환을 바꿀 수 있다고 알려져 있기 때문에 온실기체와 오존감소물질을 1960년대 수준으로 각각 고정한 실험을 통해서 두 인자간 상대적 중요성을 살펴보았다. 선행연구와 마찬가지로 과거에는 오존이 남반구 순환에 지배적인 영향을 미치고 온실가스의 영향은 모형마다 다르게 예측하여 모형별 불확실성이 컸다. 미래의 경우 오존이 회복하면서 과거와는 반대로 남반구 순환에 영향을 미치는 데 이때 온실가스의 영향과 상쇄되어 미래의 남반구 순환의 변화는 과거에 비해 그 강도가 약하게 변화하는 것을 확인 하였다. 또한 미래에는 오존과 온실가스가 비슷하게 남반구 대기 대순환에 중요한 영향을 미쳤다.1. Introduction 1 2. Data and Methodology 3 3. Results 7 3.1 Evaluation of total column ozone in CCMI models 7 3.2 Impacts of ozone depletion on Southern Hemisphere circulation changes and effects of interactive ocean 8 3.3 Comparison of the impact of stratospheric ozone and greenhouse gases on Southern hemisphere circulation changes 12 4. Summary and Conclusions 18 5. References 20 6. Tables 24 7. Figures 26 Abstract in Korean 38Maste

Evaluation of the Total Column Ozone in the Reanalysis Datasets over East Asia

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