From Miami University by Diana Udel
Study provides new details on the fate of spilled oil in the marine environment, effectiveness of chemical dispersants
A new study lead by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science demonstrates that under realistic environmental conditions oil drifting in the ocean after the DWH oil spill photooxidized into persistent compounds within hours to days, instead over long periods of time as was thought during the 2010 Deepwater Horizon oil spill.
After an oil spill, oil droplets on the ocean surface can be transformed by a weathering process known as photooxidation, which results in the degradation of crude oil from exposure to light and oxygen into new by-products over time.
The UM Rosenstiel School research team developed the first oil-spill model algorithm that tracks the dose of solar radiation oil droplets receive as they rise from the deep sea and are transported at the ocean surface.
“Understanding the timing and location of this weathering process is highly consequential. said Claire Paris, a UM Rosenstiel School faculty and senior author of the study.
“Photooxidized compounds like tar persist longer in the environment, so modeling the likelihood of photooxidation is critically important not only for guiding first response decisions during an oil spill and restoration efforts afterwards, but it also needs to be taken into account on risk assessments before exploration activities” added Ana Carolina Vaz, assistant scientist at UM’s Cooperative Institute for Marine and Atmospheric Studies and lead author of the study.
The study, titled “A Coupled Lagrangian-Earth System Model for Predicting Oil Photooxidation,” was published online on Feb 19, 2021 in the journal Frontiers in Marine Science.
The study was supported by the Gulf of Mexico Research Initiative (GoMRI): C-IMAGE III (Center for the Integrated Modeling and Analysis of the Gulf Ecosystem) and RECOVER 2 (Relationship of Effects of Cardiac Outcomes in ﬁsh for Validation of Ecological Risk).