The Ocean Reference Station at 20°S, 85°W under the stratus clouds west of northern Chile is
being maintained to provide ongoing climate-quality records of surface meteorology, air-sea
fluxes of heat, freshwater, and momentum, and of upper ocean temperature, salinity, and velocity
variability. The Stratus Ocean Reference Station (ORS Stratus) is supported by the National
Oceanic and Atmospheric Administration’s (NOAA) Climate Observation Program. It is
recovered and redeployed annually, with past cruises that have come between October and
December. Due to necessary repairs on the electric motors of the ship’s propulsion system, this
year the cruise was delayed until January.
During the 2009/2010 cruise on the NOAA ship Ronald H. Brown to the ORS Stratus site, the
primary activities were the recovery of the Stratus 9 WHOI surface mooring that had been
deployed in October 2008, deployment of a new (Stratus 10) WHOI surface mooring at that site,
in-situ calibration of the buoy meteorological sensors by comparison with instrumentation
installed on the ship by staff of the NOAA Earth System Research Laboratory (ESRL), and
collection of underway and on station oceanographic data to continue to characterize the upper
ocean in the stratus region. Both underway CTD (UCTD) profiles and Vertical Microstructure
Profiles (VMP) were collected along the track and during surveys dedicated to investigating
eddy variability in the region. Surface drifters were also launched along the track.
The intent was also to visit a buoy for the Pacific tsunami warning system maintained by the
Hydrographic and Oceanographic Service of the Chilean Navy (SHOA). This DART (Deep-
Ocean Assessment and Reporting of Tsunami) buoy had been equipped with IMET sensors and
subsurface oceanographic instruments, and a recovery and replacement of the IMET sensors was
planned. However, the DART buoy broke free from its mooring on January 3rd and was
recovered by the Chilean navy; the work done at that site during this cruise was the recovery of
the bottom pressure unit.