Monitoring of Changing Arctic Cryosphere and Circumpolar Vortex for Better Mid-latitude Climate Prediction

Potential relationships between changing Northern Hemisphere cryospheric components and hemispheric circulation patterns are examined to understand how on-going changes in the Arctic climate system may be affecting mid-latitude climate. Since the late 1980s, the vernal circumpolar vortex (CV) has retreated pole-ward in the Rockies, western Europe, and eastern Asia. An earlier snow melt is detected in all regions according to NOAA IMS snow maps. Early summer sea ice-free patterns are frequently observed in the Arctic seas since the mid 2000s, including the Barents, Kara, Laptev and Chukchi. Advection of cool air masses toward mid-latitude regions, perhaps due to the earlier melt of summertime Arctic sea ice are indicated through meandering CV patterns. This may be associated with less summertime rainfall in the monsoonal East Asian continent and with more intense rainfall events along the marginal regions of subtropical high pressure systems in the northwestern Pacific Ocean. Study results demonstrate the importance of monitoring circumpolar cyospheric components in order to provide more reliable predictions of mid-latitude seasonal conditions in a changing climate.

Key words: Arctic climate change, seasonal climate prediction, snow cover, Arctic sea ice