HF radar surface current measurements in the Mississippi Sound compared to in-situ measurements by ADCP and Lagrangian GPS surface drifters

High frequency radars are unique and powerful tools for measuring surface currents. Ocean Technologies, LLC operates and maintains two HF radar sites on the Mississippi Gulf Coast. Surface current vector data in the combined coverage area of the two sites are collected and disseminated to the Web in near real time by the Ocean Technologies (www.oceantech.net). These HF radar systems, installed along the coast of the Mississippi Sound, provide two-dimensional vector current estimates over an area of ∼520 km². Conventional and widely accepted methods to measure surface currents include acoustic Doppler current profilers (ADCPs) and Lagrangian GPS surface drifters (also called Davis drifters). This study evaluates the performance of the HF radar measurements in the Mississippi Sound against in situ measurements by ADCPs and results of Davis drifter deployments.