Magazine article Oceanus

New Findings on the Western Equatorial Pacific's Warm Pool

Magazine article Oceanus

New Findings on the Western Equatorial Pacific's Warm Pool

Article excerpt

The warmest open ocean waters in the world are found in the western equatorial Pacific. In an area the size of Australia, annual average upper ocean temperatures exceed 29 [degrees] C. This warm pool is closely associated with a combination of intense upward transport in the atmosphere, cloud cover, and rainfall that constitutes a major driving force for global atmospheric circulation. Eastward displacement of this warm pool system during El Nino/Southern Oscillation (ENSO) events every 3 to 5 years results in pronounced midlatitude weather pattern changes. Understanding the processes that couple the ocean and atmosphere in the warm pool is a crucial step toward improving predictions of seasonal-to-interannual global climate variability. Pursuit of this understanding is the primary objective of the Tropical Oceans/Global Atmosphere (TOGA) Coupled Ocean-Atmosphere Response Experiment (COARE).

What maintains the high ocean temperatures found in the warm pool? After all, other regions of the ocean have less cloud cover, and thus more solar heating, yet do not get as warm as the western equatorial Pacific. One hypothesis ascribes an important role to the large amount of precipitation - greater than 4 meters per year - that falls in the warm pool region. This rain forms a shallow, fresh - and thus buoyant - layer on the ocean surface that supports the accumulation of heat. A salt-stratified or "barrier" layer beneath it effectively insulates surface waters from cooler waters found at depth. The barrier layer is maintained over the long term through freshening of the near-surface, warm pool by rainfall that is balanced by sporadic mixing with saltier waters transported by the South Equatorial Current from the central tropical and subtropical Pacific. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.