Functioning of Coastal-river Dominated Ecosystems and Implications for Oil Spill Response: from Observations to Mechanisms and Models

Greer, A. T., Shiller, A. M., Hofmann, E. E., Wiggert, J. D., Warner, S. J., Parra, S. M., Pan, C., Joung, D., Dykstra, S., Krause, J. W., Dzwonkowski, B., Soto, I. M., Cambazoglu, M. K., Deary, A. L., Briseño-Avena, C., Boyette, A. D., Kastler, J. A., Hode, L., Nwankwo, U., Chiaverano, L. M., O’Brien, S. J., Fitzpatrick, P. J., Lau, Y. H., Dinniman, M. S., Martin, K. M., Mojzis, A. K., Howden, S. D., Moum, J. N., Hernandez, F. J., Church, I., Miles, T. N., Sponaugle, S., Book, J. W., Arnone, R. A., Cowen, R. K., Jacobs, G. A., Schofield, O., & Graham, W. M. (2018). Functioning of Coastal-river Dominated Ecosystems and Implications for Oil Spill Response: from Observations to Mechanisms and Models. Oceanography. 31(3), 90-103. DOI:10.5670/oceanog.2018.302.

Coastal river-dominated oceans represent physically complex and biologically productive regions that are also intimately connected to human socioeconomic activity. The Deepwater Horizon blowout and subsequent advection of oil into coastal waters of the northern Gulf of Mexico (nGOM) highlighted the complex linkages and lack of understanding of this river-dominated system, which resulted in imprecise information on both the oil transport and consequences for the coastal ecosystem. An interdisciplinary research CONsortium for oil exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to address these knowledge gaps through a comprehensive interdisciplinary research program that allows key biological, physical, and geochemical processes to be identified, quantitatively assessed, and incorporated into a fully-coupled physical-biogeochemical model of the nGOM shelf system. With the seasonally variable input of freshwater, salinity-driven stratification was closely tied to the increased primary production and particle abundance (a proxy for secondary production) that tended to reside near the pycnocline. The development of the pycnocline could, therefore, play a key role in exposure via marine snow and food web processes. The complex three-dimensional physical, biological, and geochemical dynamics described by CONCORDE and synthesized through the modeling effort, support an emerging oil spill response paradigm that emphasizes high resolution physical oceanography and the coupling of different components of the coastal ecosystem. The process-oriented understanding provided by CONCORDE is needed to predict ecosystem level impacts of oil spills and is applicable to other river-dominated systems worldwide, which often support oil-extraction activities.