The Importance of Dynamical Downscaling for Explanations of High Temperature Rises in Winter

The surface temperature was projected to increase from 4 to 5 degrees C in most regions around Japan in winter at the end of the 21st century, according to the Non-Hydrostatic Regional Climate Model (NHRCM) under the Represen-tative Concentration Pathway 8.5 scenario. The melting of sea ice in the Sea of Okhotsk significantly affected the tem-perature around Hokkaido Prefecture, raising it by more than 8 degrees C in some places. The temperature also rose by more than 8 degrees C in some areas in Honshu where the atmosphere was not susceptible to sea ice. The reduction in snow-covered areas due to global warming raised the temperature further and induced changes in local wind, such as airflows over mountains and wind blowing from the sea. These changes raised the seasonal average temperature and caused the tem-perature to rise by over 8 degrees C. The dynamical downscaling method played a significant role in projecting such small-scale features in the future climate.

Automated summary

According to the Non-Hydrostatic Regional Climate Model (NHRCM), the surface temperature around Japan is projected to increase by 4 to 5 degrees C in winter by the end of the 21st century. The melting of sea ice in the Sea of Okhotsk has a significant impact on the temperature in Hokkaido Prefecture, raising it by more than 8 degrees C in some places. The reduction in snow-covered areas due to global warming further raises the temperature and induces local wind changes.