# Ship Route Oil Spill Modeling: A Case Study of the Northeast Brazil Event, 2019
## 5 Conclusions  
The objective of this study was to model the dispersion of oil hypothetically released into the sea by tanker ships along the east and northeast coasts of Brazil. These studies should contribute to our understanding of the processes involved in the arrival of oil on the country's coastline during the second half of 2019. Using AIS information, we identified a total of 31 vessels comprising four main categories of oil tankers (i.e., Aframax, Panamax, Suezmax, and VLCC) that were en route within the region of interest. These routes were selected to be simulated with the oil dispersion model.  
Our results suggest that the spillage likely originated from a mobile source crossing a surface current system capable of facilitating extensive oil spreading. Notably, the region near the northeastern coast of Brazil, between 10\({}^{\circ}\) S and 13\({}^{\circ}\) S and 30\({}^{\circ}\) W and 33\({}^{\circ}\) W, was highlighted as a region where surface currents bifurcate (particularly during the months of June to August), making this the most plausible region to be reached by long-distance oil spreading.  
Our study emphasizes that the northeast/southwest (approximately 220\({}^{\circ}\)) route of oil tankers deserves further investigation in future studies on oil spill modeling, orphan oil slick identification, and potential polluters. Our results demonstrate that the coastal region in this route, especially represented by experiment 22 (Suezmax-type ship), had the highest probability of being the origin of the spillage.  
While this information is potentially valuable, it is important to emphasize that oil spill modeling is only a tool that should be complemented with other information and evidence (e.g., data from satellite surveillance, drones, and autonomous investigation vehicles) for a more comprehensive and accurate analysis of scenarios. Furthermore, preventative actions, continuous monitoring, and international cooperation are essential for further reducing the risks of environmental accidents and to protect the environment and communities affected by maritime oil transportation.  
Conceptualization, A.L.; formal analysis, A.L., L.A., L.F. and D.B.; methodology, L.A., L.F. and P.N.; project administration, P.N.; supervision, A.L.; writing--original draft, A.L.; writing--review and editing, L.A., L.F., D.B., R.G., R.M. and P.N. All authors have read and agreed to the published version of the manuscript.  
This work was partially supported by Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq Grant No. 440857/2020-1, CNPq/MCTI 06/2020-Pesquisa e Desenvolvimento para Enfrentamento de Derramamento de Oleo na Costa Brasileira, Programa Ciencia no Mar, and Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior-CAPES finance code 001, the National Institute of Science and Technology for Climate Change Phase 2 under CNPq Grant 465501/2014-1, FAPESP Grant 2014/50848-9 and CAPES Grant 16/2014.  
Not applicable.  
The datasets presented in this article are not readily available because they were generate throughout an individual academic license of the model. Requests to access the datasets should be directed to the corresponding author/s.  
The authors acknowledge the support of the Brazilian Navy--MB in the completion of this study and the Instituto Nacional de Pesquisas Espaciais--INPE.  
The authors declare no conflicts of interest.