The Pacific Decadal Oscillation (PDO) is a low-frequency seesaw (ENSO-like) pattern of sea surface temperature in the Pacific Ocean, but varies on decadal (20 to 30 year) time scales. On decadal time-scales the PDO has been identified as a source of ocean-atmosphere climate variability that has impacts over the U.S. Recent studies have shown that ENSO and PDO can reinforce or weaken each other's effects.
A long-lived El Niño-like pattern of Pacific climate variability. The Pacific Decadal Oscillation operates at something on the order of a 20- to 30-year time scale, while El Niño/La Niña events are typically on the order of 6 to 18 months in length. Both phenomena correlate with relatively wetter or drier periods in the western portion of North America.
cyclic variations in sea-surface temperature in the Northern Pacific—an example of natural climate variability. These occur on decadal timescales and affect the weather in places like the U.S. Pacific Northwest region.
A long-term El Niño-like pattern of North Pacific climate variability, with phases that persist from 20-30 years. The positive (warm) phase of the PDO is characterized by cooler than average SSTs and air pressure near the Aleutian Islands and warmer than average SSTs near the California coast; these conditions tend to enhance El Niño teleconnections. The negative (cool) phase tends to enhance La Niña teleconnections (i.e., winter wetness in the Pacific Northwest and winter dryness in the Southwest United States).
A pattern of climate and ocean condition regimes occurring in the north Pacific Ocean (associated with the Aleutian low pressure system) that results in shifts in sea surface temperatures and plankton abundance on a decades long time scale.
A long-lived El Niño-like pattern of Pacific climate variability. While the two climate oscillations have similar spatial climate fingerprints, they have very different behavior in time. Two main characteristics distinguish Pacific Decadal Oscillation (PDO) from El Niño / Southern Oscillation (ENSO): first, in the 20th century, PDO "events" persisted for 20 to 30 years, while typical ENSO events persisted for 6 to 18 months; second, the climatic fingerprints of the PDO are most visible in the North Pacific / North American sector, while secondary signatures exist in the tropics; the opposite is true for ENSO.
Sometimes defined as the first empirical orthogonal function (EOF) of North Pacific SST anomalies. Postulated to have inherent decadal variations.
A large pool of warm water that moves north and south in the Pacific Ocean every 30 years or so and has large effects on North America's climate.
The Pacific Decadal Oscillation (PDO) is a pattern of Pacific climate variability that shifts phases on a multi-decadal time scale, usually about 20 to 30 years. The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N. During a "warm", or "positive", phase, the west Pacific becomes cool and part of the eastern ocean warms; during a "cool" or "negative" phase, the opposite pattern occurs.
