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The U.S. Repeat Hydrography CO2/Tracer Program, having recently completed a decade of full-depth surveys of the world’s ocean basins, has compiled a report summarizing programmatic and scientific achievements. As a contributor to the international Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP), the U.S. program has advanced understanding of the role of the ocean in climate change, carbon cycling, and biogeochemical responses. The report highlights key scientific discoveries and presents future science and monitoring objectives.

The document is the test report of the Prague test campaign that were conducted in the Integrated Project EMMA, a project of the sixth framework programme of the European Commission. It contains all results and conclusion that were gained with real time simulations and technical and operational trials at Prague Airport.

Several 5 to 10 m s-1 westerly wind bursts of 10-15 days' duration occurred in the Western Equatorial Pacific during november 1989 to January 1990. The response to these wind bursts was characterized by a 400- to 600 km wide eastward jet in the upper 100-150 m along the equator between 135°E and the date line. Flow in this jet accelarated to speeds of over 100 cm s-1 within 1 week after the onset of westerly winds in november 1989 in association with super thyphoon Irma. In addition, a 20 to 40 cm s-1 westward counterflow developed between 2°N and 2°S below the surface jet separating it from the eastward flow of the Equatorial undercurrent in the thermocline. Changes in surface layer zonal volume transport in the Western Pacific due to westerly wind bursts were 25-56 Sv based on comparison of three shipboard velocity transects in november and december 1989. Although fluctuations in current speeds in the thermocline were generally smaller and less directly related to local wind forcing than those in the surface layer, the Equatorial undercurrent decelerated to less than 20 cm s-1 (i.e., less than half its speed before the onset of westerlies) by early december 1989. (D'après résumé d'auteur)

A series of 12 meridional transect along longitude 165°E in the Western Equatorial Pacific ocean were made between mid-1986 and mi-1988 : a time interval spanning an El Nino/Southern Oscillation (ENSO) event. Data collected on these cruises provide a detailed (albeit temporally sparse) view of the oceanic changes which occur in the Western Pacific during an ENSO event. The present work focuses on the evolution of the upper ocean thermohaline and zona velocity fields as revealed by high resolution hydrographic casts and direct near surface velocity measurements. (D'après résumé d'auteur)

As the ensemble of current profile sections in the western tropical Pacific increases, we begin to get a picture of the annual and interannual variability of circulation in the region. The data sets considered here - ADCP sections from two WEPOCS cruises and 4 US/PRC TOGA cruises - do not resolve the seasonal cycle, but they do span the 1986-87 El Nino event and show some of the current variability associated with it. The most striking result is the contrast between the ever-present New Guinea coastal undercurrent and equatorial undercurrent on 141°E, and the lack at 165°E of any persistent currents other than the Tsuchiya jets. The net transports across 165°E of water warmer than 26° were 77 x 10 (puissance 6) m3 s-1 to the east in december 1986, early in the El Nino event, and 50 x10 (puissance 6) m3 s-1 to the west in May 1988, following the event. There was little net transport in october 1987. (Résumé d'auteur)