James W. Murray Current Projects-EqPac, A US JGOFS Process Study in the Central Equatorial Pacific

Chemical Oceanography, UW School of Oceanography

EqPac was a US JGOFS Process Study in the central equatorial Pacific. The project was essentially a top to bottom study of the carbon cycle in a region that plays a major role in the global carbon cycle. The nuts and bolts of the project are described in the following publications.

• The overview of the project, problems to be solved, participants and cruise plan was described in Murray et al (Oceanography, 5, 134-142, 1992)
• Summaries of the initial results were published by Murray et al (Science, 266, 58-65, 1994), Barber et al (Ambio, 23, 62-66, 1994), Yoder et al (Nature, 371, 689-692) and Feely et al (Geophysical Research Letters, 21, 277-280, 1994).
• The individual science results are being published primarily in special issues of Deep-Sea Research II. Volume I of the special issue was published as J.W. Murray, ed (Deep-Sea Research II, 42, 1995). This volume contains 28 papers and the table of contents is given here.
• Volume II of the DSR II special issue was published as J.W. Murray, ed (Deep- Sea Research II, 43, 1996). This volume contains 28 papers. The table of contents is available here. This volume includes a paper by our group: Murray J.W., J. Young, J. Newton, J. Dunne, T. Chapin, B. Paul and J.J. McCarthy "Export flux of particulate organic carbon from the central equatorial Pacific determined using a combined drifting trap-234Th approach".
• Volume III of the DSR special issue was published in 1997 (Deep-Sea Research II, 44, 1997). It contains 25 synthesis papers from the US JGOFS project and papers by participants in International JGOFS Studies. Many of these papers were presented at the NATO Advanced Study Workshop held in Noumea, New Caledonia in June 1995. You can view the table of contents.

The extensive data from this project, resides in the US JGOFS data system on the US JGOFS Home Page . Much of the EqPac synthesis is now being conducted as part of the International JGOFS Equatorial Pacific Synthesis Group (EPSG) chaired by Robert LeBorgne (ORSTOM/Marseille).

Go to the Home Pages of Archer , Feely, or Flament for other nifty figures from EqPac. Some meridional sections of the hydrographic and nutrient data from the EqPac Survey I Cruise (12° N to 12° S along 140° W) are given below.

Zonal current and hydrographic data from EqPac Survey I (Feb-March, 1992). The high surface temperature and low velocity of the equatorial undercurrent reflect the El Nino conditions that existed at the time of this cruise.

Here are nitrate, nitrite and ammonia for Survey I. The analyses were done by Chris and Jean Garside (Bigelow Labs). There is elevated surface nitrate (2-3 µM) but it is much lower that normal. There are subsurface maxima for nitrite and ammonia asymmetrically distributed toward the south.

e-mail: jmurray@u.washington.edu

updated 30 October 2001