지구온난화의 지역적 특성: 전례 없는 기후 시기의 선형 전망

Abstract

Given an external forcing globally uniform, the corresponding climate change and impacts differ by region. Thus the detection of global warming signal against internal variability has been made on a regional scale as well as on a global average. The purpose of this study is to estimate a timing of unprecedented climate due to global warming and to analyze the regional differences therein. Unlike previous studies that used model output, we used an observational dataset to estimate a magnitude of internal variability and a future temperature change. We calculated a linear trend in surface temperature using a historical record since 1880 and a magnitude of internal variability as the largest displacement from thetrend. A timing of unprecedented climate was defined as the first year when a predicted minimum temperature exceeds the recorded maximum and remains as such since then. Presumed that the linear trend and the maximum displacement will be maintained in the future, an unprecedented climate would come within 200 years over the Indian Ocean, parts of the Atlantic and high-latitude regions but after thousands of years over the eastern tropical Pacific and the middle-latitude NorthPacific where an internal variability is large. As such, a timing of an unprecedented climate over the ocean is highly affected by large internal variability except for the high-latitude regions with a significant warming trend.rage. The purpose of this study is to estimate a timing of unprecedented climate due to global warming and to analyze the regional differences therein. Unlike previous studies that used model output, we used an observational dataset to estimate a magnitude of internal variability and a future temperature change. We calculated a linear trend in surface temperature using a historical record since 1880 and a magnitude of internal variability as the largest displacement from thetrend. A timing of unprecedented climate was defined as the first year when a predicted minimum temperature exceeds the recorded maximum and remains as such since then. Presumed that the linear trend and the maximum displacement will be maintained in the future, an unprecedented climate would come within 200 years over the Indian Ocean, parts of the Atlantic and high-latitude regions but after thousands of years over the eastern tropical Pacific and the middle-latitude NorthPacific where an internal variability is large. As such, a timing of an unprecedented climate over the ocean is highly affected by large internal variability except for the high-latitude regions with a significant warming trend.