摘要:We have conducted an ensemble of 20 simulations using a high resolution global ocean
model in which dye was continuously injected at the site of the Deepwater Horizon drilling
rig for two months. We then extended these simulations for another four months to track
the dispersal of the dye in the model. We have also performed five simulations in which dye
was continuously injected at the site of the spill for four months and then run them out to
one year from the initial spill date. The experiments can elucidate the approximate
timescales and space scales of dispersal of polluted waters and also give a quantitative
estimate of the dilution rate. Given the uncertainty in rates of chemical or biological
degradation for oil or an oil–dispersant mixture, we do not include a decay term
for the dye. Thus, these results should be considered an absolute upper bound
on the possible spatial extent of the dispersal of oil or oil–dispersant mixture. The model results indicate that it is likely that oil-polluted waters from the Deepwater
Horizon incident will, at some time over the six months following the initial spill date, be
transported at relatively low concentrations over a significant part of the North-West
Atlantic Ocean. However, this does not imply that oil will reach the eastern shores of North
America, or that it will even be detectable. We present probabilities for the transport
timescales and estimates of ensemble mean arrival times, and we briefly discuss the
likely dispersion timescales and pathways of dye released in the subsurface ocean.