Townsend Cromwell
Student Connection
Just in from the Ship
May 07, 2000 The TOWNSEND CROMWELL is back in Honolulu having completed the third leg of TC-00-04. We spent two days
doing CTDs (left) around the clock in the same spot. We attached
an acoustic current profiler to
the CTD (right)frame to provide ground truth for a
computer model of currents and waves along the Hawaiian Island ridge. Ground truth is data
that comes from direct measurement in the field as compared to computer model data,
satellite data or other remote or indirect means. Ground truth is very valuable to
scientists who use these indirect methods for monitoring environmental systems because it
provides them with real measurements to compare with their calculations.
The acoustic profiler is used to measure currents by
sending sound waves out and then recording the waves that are reflected back off of
plankton, small fish and particles in the water. The profiler processes the reflected
sound and calculates the current speeds and directions that they are being carried in. The
scientists end up with a vertical profile of currents in the entire water column.
We are now loading
equipment and supplies for TC_00_05 which will be a Marine Mammal Research Program cruise
where we will transport people and supplies to small islands in the far reaches of the
Hawaiian Island chain. Field scientists live on these little islands for months at a time
studying and rehabilitating the fragile ecosystems that support several protected and
endangered species.
Other Reports from This Cruise:
Last modified May 08, 2000