Warm Arctic-Cold Continents Phenomenon: From Peak to Plummet in the 2030s
Yungi Hong, Gwangju Institute of Science and Technology
Simon Wang, Utah State University
Using large ensemble simulations, this study projects a rapid decline in Warm Arctic-Cold Continent (WACC) events in East Asia and North America starting in the 2030s, reversing the increasing trend observed until 2020.
The anticipated shift in WACC patterns has major implications for communities impacted by extreme winter weather, prompting them to prepare for changes. It also encourages the climate forecasting community to update conceptual models for improved adaptation and mitigation approaches.
This study employs CESM large ensemble simulations to assess the projected trajectory of Warm Arctic-Cold Continent (WACC) events in East Asia and North America through 2100. While validating the intensification of WACC until the 2020s, the findings indicate a marked decrease beginning in the 2030s. Analysis reveals a northward shift of cold temperature thresholds, suggesting global warming's impact on constraining the southward expansion of Arctic cold air. The different timing of decline onset between the two regions implies a weakening teleconnection with continued warming. These results underscore the need for impacted communities to anticipate changes in extreme winter weather and for the climate forecasting community to update models accordingly. Further research using multiple climate models and WACC definitions is recommended to comprehensively evaluate the dynamics of this impending shift.