Meeting Abstracts
Forecasting sudden changes of the oil slick shape during the Deepwater Horizon oil spill
Maria Olascoaga, George Haller
RSMAS
(Abstract received 05/12/2012 for session C)
ABSTRACT
We present a methodology to predict major short-term changes in environmental contamination patterns. Our approach is based on the objective (frame-independent) identification of key material curves, widely known as Lagrangian Coherent Structures (LCSs), that drive tracer mixing in unsteady two-dimensional flows defined over a ?finite-time interval. More specifically, some of these LCSs admit highly attracting cores that lead to inevitable material instabilities even under future uncertainties or unexpected perturbations to the observed flow. As such, these LCS cores have the potential to forecast imminent shape changes in the contamination pattern, even before the instability builds up and brings large masses of water into motion. Exploiting this potential, our methodology, which we refer to as LCS-core analysis, provides a model-independent forecasting scheme that relies only on already observed or validated flow velocities at the time the prediction is made. This is illustrated by making forecasts of two major instabilities that occurred in the shape of the oil slick during the Deepwater Horizon oil spill in the Gulf of Mexico.