Daniel Swain: New insights into the Ridiculously Resilient Ridge & North American Winter Dipole
Ultimately, we confirm that unusual ocean temperatures are linked to seasonally-persistent West Coast winter ridging similar to the Triple R. Tropical warmth (in the West Pacific) and coolness (in the East Pacific) are both linked to different patterns of North Pacific winter ridging, and may offer an early warning of seasons with an elevated risk of dry conditions in California. Interestingly, tropical Pacific Ocean temperatures during autumn 2017 were warm in the west and cool in the east amidst a modest (and ongoing) La Niña event—a combination that suggests a substantially elevated likelihood of West Coast ridging this winter. To date, Southern California has experienced one of its driest starts to the Water Year on record, and strikingly persistent West Coast ridging is now expected to last at least two weeks. It will certainly be interesting to see how this winter plays out in the context of these new research findings.
The Full Article HERE.