The Pacific decadal oscillation, air-sea interaction and central north Pacific winter atmospheric regimes
Article first published online: 7 DEC 2012
Copyright 2000 by the American Geophysical Union.
Geophysical Research Letters
Volume 27, Issue 5, pages 731–734, 1 March 2000
How to Cite
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Accepted: 10 DEC 1999
- Manuscript Received: 3 JUN 1999
Prominent and persistent anomalies in the atmospheric flow (troughs and ridges) occur sporadically over the central North Pacific, and can have profound consequences for the weather of North America. We have examined how these events are associated with large scale central North Pacific sea surface temperature (SST) anomalies, using an index for the Pacific Decadal Oscillation (PDO). The anomalies in turbulent air-sea heat fluxes and low-level baroclinity associated with the PDO are manifested differently during troughs than during ridges in their effects on the transient eddies (storms). These effects may help explain why prominent troughs (ridges) occur about 3 (2.5) times more frequently during periods when the PDO is significantly positive (negative) than of opposite sign. Our results suggest that the state of the mid-latitude Pacific Ocean more fundamentally affects the atmosphere than has been thought.