Influence of projected climatic conditions and varying lateral points of release on oil slick transport in a tide-dominated estuary

Oil spills in estuarine systems can strongly endanger habitats and water quality. However, the impacts of projected climatic conditions on oil spill transport in estuarine environments have received little attention. To address these key gaps, we analyse here a range of simulations for the Humber Estuary, UK, using coupled hydrodynamic and oil spill model. These simulations indicate that, for this well-mixed macro-tidal estuary: (a) the influence of projected sea level rise and river discharge on oil slick impacted area, slick length and overall distance travelled is relatively minor (<10%); (b) magnitude of currents determines differences in dynamics between oil slicks released along the estuary length; and (c) differences in lateral current speed and direction are key determinants of the differences in the dynamics of oil slicks released along the estuary width. The implications of these findings for operational oil spill response in estuaries similar to the Humber Estuary are: (i) the need to be aware of dominant current direction in different segments of the estuary; and (ii) the need to take cognisance of the interactions between oil slicks and estuary bank and how it influences overall distance travelled by oil slicks.