Projected changes of the warm Arctic-cold North American pattern

The Warm Arctic - Cold North American (WACNA) pattern features opposing surface temperature anomalies, with centers over the Chukchi - Bering Seas (CBS) and the North American Great Plains. This pattern is found to be driven and sustained by meridional heat transport along temperature gradients, primarily damped by the covariance between temperature and diabatic heating. The Canadian Earth System Model CanESM5, part of the Coupled Model Intercomparison Project Phase 6 (CMIP6), reasonably reproduces this pattern and its formation mechanisms. CanESM5 projections under the Shared Socioeconomic Pathway 8.5 (SSP5-8.5) suggest a significant weakening of the WACNA pattern with continued global warming. Notable changes in pattern intensity and spatial structure are anticipated, particularly a decrease in intensity over the CBS. These changes are attributed to Arctic amplification associated with global warming, which diminishes the equator-to-pole temperature gradient and consequently reduces meridional heat transport, particularly over the CBS region.