Evaluation of new weathering algorithms for oil spill modeling

Abstract

Increasing production and transportation of oil has increased the risk of oil spills. The transport and fate of spilled oil are important factors to consider in oil spill response. However, challenges remain in the observation and analysis of these factors, especially during the short initial period that is critical for response. The challenges result from the complexity and uncertainty of oil properties and the environmental conditions, as well as their interactions. Oil spill models have become important tools in facilitating oil spill response. Over recent decades, more than 50 oil spill models have been developed, yet limitations still exist including: (1) natural dispersion algorithms are mainly based on empirical equations with insufficient theoretical support; and (2) oil biodegradation algorithms must represent the complexity of this process with limited knowledge and information. In order to help fill the existing gaps, this study develops (1) a dispersion model based on the modified Weber number scaling approach of Stiftelsen for industriell og teknisk forskning (SINTEF); and (2) a new biodegradation model based on the coupling of pseudo-component and exponential decay biodegradation algorithms. The newly developed models are incorporated into the Modelo Hidrodinâmico (MOHID) model. It is shown that the newly developed dispersion and biodegradation algorithms extend the capability of MOHID.