전지구 기후모델을 이용한 동해의 열속 균형에 대한 지구 온난화 효과 연구

Abstract

Observations show the East/Japan Sea (EJS) has undergone drastic changes in a past few decades such as a warming of upper and deep waters, and a decrease in dissolved oxygen contents in deep waters. No postulation, however, has been attempted concerning the future oceanographic states of the EJS as the climate continues to change. Motivated by this gap, we analyzed results from a high-resolution global coupled climate model (MIROC-hi, T106L56AGCM + 0.28 0.16 L48 OGCM) to examine climate change projections over the EJS. In this study, three experiments using MIROC-hi (20C-run, A1B-run, and B1-run) with different external conditions (i.e. solar and volcanic forcing, GHG concentrations, aerosol emission, and land use) are compared to investigate the response of the EJS to global warming.Mean surface circulation and inflow volume transport from the 20C-run experiment are comparable to the observations, while the partitioning of outflows and a sharp increase in deep water temperature lack realism. The latter appears to happen because the deep water formation is not properly reproduced in the model. Long-term averaged heat budget estimated from model products is consistent with other estimations based on observational data. Both scenario runs indicate a warming of the basin-averaged sea surface temperature as compared to that from the 20C-run (A1B-run: +4℃, B1-run: +3℃). The warming signal is significant in the northern part of the EJS and near the subpolar front. Changes in other oceanographic fields and atmospheric conditions will be presented.