Recent strengthening of the stratospheric Arctic vortex response to warming in the central North Pacific.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29703910.
- Also identified by DOI 10.1038/s41467-018-04138-3 and PMC identifier 5923267.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The stratospheric Arctic vortex (SAV) plays a critical role in forecasting cold winters in northern mid-latitudes. Its influence on the tropospheric mid- and high-latitudes has attracted growing attention in recent years. However, the trend in the SAV during the recent two decades is still unknown. Here, using three reanalysis datasets, we found that the SAV intensity during 1998-2016 has a strengthening trend, in contrast to the weakening trend before that period. Approximately 25% of this strengthening is contributed by the warming of sea-surface temperature (SST) over the central North Pacific (CNP). Observational analysis and model experiments show that the warmed CNP SST tends to weaken the Aleutian low, subsequently weakening the upward propagation of wavenumber-1 planetary wave flux, further strengthening the SAV. This strengthened SAV suggests important implications in understanding the Arctic warming amplification and in predicting the surface temperature changes over the northern continents.