Ja. Harlan et al., COMPARISON OF OVER-THE-HORIZON RADAR SURFACE-CURRENT MEASUREMENTS IN THE GULF-OF-MEXICO WITH SIMULTANEOUS SEA TRUTH, Radio science, 33(4), 1998, pp. 1241-1247
On June 14, 1995, the U.S. Navy's Relocatable Over-the-Horizon Radar (
ROTHR) west of Corpus Christi, Texas, mapped the radial component of o
cean surface current with 15-km resolution over a 230,000-km(2) area i
n the Gulf of Mexico. Concurrently, an oceanographic research vessel m
easured near-surface currents within part of the area illuminated by t
he radar, providing an opportunity to compare radar-derived surface cu
rrents with in situ sea truth. The R/V Gyre, operated by Texas A&M Uni
versity, twice traversed the Gulf of Mexico Loop Current while measuri
ng current vectors with an acoustic Doppler current profiler (ADCP). W
e compared radar-derived currents with currents measured in the upperm
ost ADCP bin (centered at IO-m depth). Lf only radar data exceeding a
quality threshold are considered, the rms difference in the radial cur
rents measured by the two techniques is 27 cm s(-1). This difference m
ost likely reflects the different sampling employed by these instrumen
ts, as well as unremoved ionospheric biases in the radar measurements.