Pan American Climate Study (PACS) mooring deployment cruise report : R/V Roger Revelle cruise number Genesis 4, 9 April-5 May 1997

Abstract

Three surface moorings were deployed in the eastern equatorial Pacifc from the R/V Roger Revelle as part of the Pan American Climate Study (PACS). PACS is a NOAA-funded study with the goal of investigating links between sea surface temperature varabilty in the tropical oceans near the Americas and climate over the American continents. The three moorings were deployed near 125°W, spanning the strong meridional sea surface temperature gradient associated with the cold tongue south of the equator and the warmer ocean north of the equator, near the northernmost, summer location of the Intertropical Convergence Zone. The mooring deployment was done to improve understading of the air-sea fluxes and of the processes that control the evolution of the sea surface temperature field in the region. Two surface moorings of the Upper Ocean Processes Group at the Woods Hole Oceanographic Institution (WHOI) were deployed-one at 3°S, 125°W and the other at lO°N, 125°W. One mooring from the Ocean Circulation Group (R. Weisberg) at the University of South Florida (USP) was deployed on the equator at 128°W. The buoys of the two WHOI moorings were each equipped with meteorological instrmentation, including a Vector Averaging Wind Recorder, and an Improved Meteorological (IMET) system. The WHOI moorings also carried Vector Measurng Current Meters, single-point temperature recorders, and conductivity and temperature recorders located in the upper 200 meters of the mooring line. In addition to the instrumentation noted above, a variety of other instruments, including an acoustic current meter, acoustic doppler current meters, bio-optical instrument packages and an acoustic rain gauge, were deployed during the PACS field program. The USF mooring had an IMET system on the surface buoy and for oceanographic instrumentation, two RD Instruments acoustic doppler current profilers, single-point temperature recorders, and conductivity and temperature recorders. Conductivity-temperature-depth (CTD) profiles were made at each mooring site and during the transit between mooring locations. This report describes, in a general manner, the work that took place durig the Genesis 4 cruise aboard the R/V Roger Revelle. The three surface moorings deployed during this cruise will be recovered and re-deployed after approximately nine months, with a final recovery planned for 17 months after the first setting. Details of the mooring designs and preliminary data from the CT profies are included.