The Equatorial Pacific Process Study (EQPAC) was conducted along 140 deg W
longitude during 1992.
Four cruises took place: February 3 - March 9, March 19 - April 15,
August 5 - September 18, and September 24 - October 21. A fifth benthic
cruise and sediment trap legs were added. During the first cruise
(TT007), 15 stations ... were occupied along 140 deg W longitude from
12 deg N latitude to 12 deg S latitude. During the second cruise
(TT008), data was collected at 8 stations along 140 deg W longitude
from 9 deg S latitude to 9 deg N latitude. During the third cruise
(TT011), data was collected at 15 stations along 140 deg W from 12 deg N
latitude to 12 deg S latitude. During the fourth cruise (TT012), data was
collected at 5 stations along 140 deg W longitude from 17 deg S
latitude to the equator.
Water bottles were mounted on a rosette CTD and cast at each
station to different depths. Total carbon dioxide was measured using
coulometric techniques. Partial pressure of carbon dioxide in sea
water was measured using two methods: 1) a gas-seawater equilibrator
combined with a gas chromatograph, and 2) an NDIR analyzer. Total
alkalinity was measured by titration. Partial pressure of carbon
dioxide in sea surface air was also measured. Sea surface temperature
and salinity were measured as well.
The data is public domain and can be retrieved on-line at