Validation of HF Radar Measurements

reasonably ask how accurate can such remote measurements be made?HF RADARS ARE A UNIQUE and powerful tool for measuring surface currents.They provide an unparalleled window into the spatial variations of near-surface currents.But oceanographers who are more accustomed to measuring currents with instruments that actually get wet may reasonably ask how accurate can such remote measurements be made?And while this is an easy and obvious question to ask, it is an interestingly difficult question to answer.We have been studying the accuracy of the OSCR HF radar system through analysis of data from the Office of Naval Research (ONR)-sponsored High-Resolution Remote-Sensing Experiment that was conducted off Cape Hatteras, North Carolina during the summer of 1993.This experiment provided a unique opportunity to examine the complex questions of HF radar accuracy.Along with several weeks of HF radar data, we had access to multiple in situ measurements of current from both moored and ship-based devices.In a series of analyses, we have attempted to validate the HF current measurements through comparison with the in situ data, The key has been to examine the temporal and spatial variations within these data in order to distinguish the sources of the underlying differences between the systems we compare.