Airborne Ocean Surveys of the Loop Current Complex From NOAA WP-3D in Support of the Deepwater Horizon Oil Spill.

摘要

At the time of the Deepwater Horizon oil rig explosion, the Loop Current (LC), a warm ocean current in the Gulf of Mexico (GoM), extended to 27.5 N just south of the rig. To measure the regional scale variability of the LC, oceanographic missions were flown on a NOAA WP-3D research aircraft to obtain ocean structural data during the spill and provide thermal structure profiles to ocean forecasters aiding in the oil spill disaster at 7 to 10 day intervals. The aircraft flew nine grid patterns over the eastern GoM between May and July 2010 deploying profilers to measure atmospheric and oceanic properties such as wind, humidity, temperature, salinity, and current. Ocean current profilers sampled as deep as 1500 m, conductivity, temperature, and depth profilers sampled to 1000 m, and bathythermographs sampled to either 350 or 800 m providing deep structural measurements. Profiler data were provided to modeling centers to predict possible trajectories of the oil and vector ships to regions of anomalous signals. In hindcast mode, assimilation of temperature profiles into the Hybrid Coordinate Ocean Model improved the fidelity of the simulations by reducing RMS errors by as much as 30% and decreasing model biases by half relative to the simulated thermal structure from models that assimilated only satellite data. The synoptic snapshots also provided insight into the evolving LC variability, captured the shedding of the warm core eddy Franklin, and measured the small-scale cyclones along the LC periphery.