MODELING OIL SPILL TRAJECTORY IN THE GULF OF PARIA, TRINIDAD, WEST INDIES

Abstract

ABSTRACT The Gulf of Paria (GOP) is a semi-enclosed basin that provides access for all sea-going traffic to the four major ports on the west coast of Trinidad. This traffic includes tourist cruise liners, powerboats and yachts for recreation; cargo ships for transporting methanol, ammonia, and urea; tankers carrying crude oil and refined products to and from the refinery; and large, liquefied natural gas tankers. The GOP is considered a high-risk area for marine accidents and related spills because of this voluminous oceanic traffic. It also supports a range of fragile ecosystems including several beaches and the Caroni swamp, all of which can be adversely affected by any kind of discharge into this area. Petroleum Company of Trinidad and Tobago Limited (PETROTRIN), in discharging its responsibility, has put in place many systems to mitigate the damage resulting from such a situation should it occur. The most recent has been the acquisition of a commercially available software package that can be used to predict the movement of oil spills during an actual incident. Wind speed and direction, and mean tidal and background currents for the GOP were used to customize the model for the marine area bounded by the points 10.0234°N 62.2059°W, 10.0234°N 61.4911°W, 10.06796°N 61.4911 °W, and 10.06796 °N 62.2059 °W. The movements of surface drifters launched from a boat were recorded with time using a handheld global positioning system (GPS). Model simulations were generated and compared with field data to determine the model's capabilities and limitations for predicting the spill movement in the GOP. The trajectories predicted by the model were consistent with the actual movement of the surface drifters. Continuous updates of the movement of an actual spill will allow improved predictions and thereby assist response teams in determining and prioritizing the next course of action.