[A-CG42] 北極域の科学

[ACG42-05] 様々な共通社会経済経路における北極の地表気温年々変動と北極航路利用可能性の将来変化

*相澤 拓郎^1,2、大島 長²、行本 誠史²、牛島 悠介² (1.国立極地研究所、2.気象庁気象研究所)

キーワード：北極、気候モデル、地表気温、年々変動、将来変化、北極海航路

Changes in the regions covered by sea ice have extensive impacts not only on the Arctic climate change or the Arctic marine ecosystem, but also on various aspects of human activities and socio-economic endeavors. However, climate model projections of future Arctic sea ice areas are still challenging. We conducted the single model analysis based on Meteorological Research Institute Earth System Model version 2.0 (MRI-ESM2.0) and found that, as global warming progresses in the future, it is expected that the year-to-year variability in surface air temperatures over the regions covered by sea ice in the present-day will exhibit a slight increase in the summer, but notably decrease during autumn to spring. Moreover, we found that, even when fully considering the year-to-year variability of sea ice concentrations, MRI-ESM2.0 forecasts that by the early 2030s, the vessels will be able to safely navigate along the northern coast of the Eurasian Continent in at least September. The accessibility of the northern sea route is projected to increase in the future in scenarios which economic development relies on fossil fuels or which regional fragmentation intensifies. We also found that the stabilization of the Arctic shipping route is important for a decrease in the year-to-year variability in surface air temperature.