In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East
Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key region where the June sea-ice
variability exerts the most significant impacts on the East Asian August tripole rainfall pattern, and explores the teleconnection
mechanisms involved. The results reveal that a reduction in June sea ice excites anomalous upward air motion due to strong
near-surface thermal forcing, which further triggers a meridional overturning wave-like pattern extending to midlatitudes.
Anomalous downward motion therefore forms over the Caspian Sea, which in turn induces zonally oriented overturning
circulation along the subtropical jet stream, exhibiting the east–west Rossby wave train known as the Silk Road pattern. It is
suggested that the Bonin high, a subtropical anticyclone predominant near South Korea, shows a significant anomaly due to
the eastward extension of the Silk Road pattern to East Asia. As a possible descending branch of the Hadley cell, the Bonin
high anomaly ultimately triggers a meridional overturning, establishing the Pacific–Japan pattern. This in turn induces an
anomalous anticyclone and cyclone pair over East Asia, and a tripole vertical convection anomaly meridionally oriented over
East Asia. Consequently, a tripole rainfall anomaly pattern is observed over East Asia. Results from numerical experiments
using version 5 of the Community Atmosphere Model support the interpretation of this chain of events.

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• Teleconnection between Sea Ice in the Barents Sea in June and the Silk Road, Pacific–Japan and East Asian Rainfall Patterns in August