As concern grows after the explosion of the Deepwater Horizon drilling rig in the Gulf of Mexico two weeks ago, scientists are monitoring the situation closely with ESA's Envisat radar data.
The spill still appears relatively confined around its point of origin and is still north of the Loop Current, a powerful conveyor belt that circulates clockwise around the Gulf toward Florida before being joining the powerful Gulf Stream.
Some researchers have expressed concerned that the Loop Current could soon catch the oil slick and drag it south towards coral reefs in the Florida Keys.
By combining surface roughness and current flow information with Envisat Advanced Synthetic Aperture Radar (ASAR) data of the spill, SAR image analysts are able to detect the direction in which the spill boundaries can drift.
(Photo Credit: CLS)
In these two ASAR images for April 29 and May 2, advanced processing methods have been performed to display ocean surface roughness variations and Doppler-derived ocean surface radial velocities. Merging this information provides insight into the spatial structure of the spill and its dispersion by the upper ocean turbulent flow.
In the 29 April image, smooth surfaces appear as black patches inside the oil spill and in the very low wind region east of the spill, where the flow analysis is not possible.
An intriguing shape is detected in the 2 May image that seems to follow passively the flow derived from the Doppler measurements.
(Photo Credit: CLS)
The fear is that winds could push the oil slick south until it joins the Loop Current, which would carry the oil towards Florida. If that were to happen, the oil could flow into the Gulf Stream and be carried up to the US East Coast.
"As observed, this does not seem to be the case at the moment as no connection between the spill and the intense current presently occurs," said Dr Bertrand Chapron of IFREMER, the French Research Institute for Exploitation of the Sea.
