The December–February surface air temperature (SAT) trend is examined for all consecutive 20-year time periods between 1979 and 2017, from which a transition from a cold-Arctic-warm-continent toward a warm-Arctic-cold-continent trend pattern is evident. This transition is accompanied by a consistent transition in the sea level pressure trend pattern that supports warm air advection over the Arctic and cold air advection over the continents. The regression of the detrended December–February-average SAT onto a detrended index defined to quantify the east-west gradient of tropical Pacific sea surface temperature is characterized by a warm-Arctic-cold-continent pattern much like the SAT trend pattern observed in recent decades. A decadal timescale warming of the western tropical Pacific water has increased the east-west gradient of tropical Pacific sea surface temperature, thus contributing to the observed extratropical SAT trend transition.
All Science Journal Classification (ASJC) codes
- Earth and Planetary Sciences(all)