Scientific Methodology

Atlantic release points

Oil spill hazard mapping from simulations builds the oil spill distribution along the coasts sampling the current fields every 5 days and using oil sources of pollution generated in a 25 km grid all along the coastlines.

The oil spill hazard mapping method applied in GLAMOR is based on the work developed by Sepp Neves et al., (2015) and later improved by Sepp Neves et al., 2016. The methodology is aligned with modern and standardized concepts of risk (ISO 31000 – Risk management principles) critically adapted to the oil spill case. The user can find the theoretical basis of our method in Sepp Neves et al., 2015.

The reasoning behind the ensemble members configuration is presented in Sepp Neves et al., 2016, where the user will also find the results obtained with a small scale case study carried out off the Portuguese coast. Missing points detected during the case study were solved and a robust oil spill hazard quantification method has been proposed employing an objective criteria to evaluate the suitability of the experiment setup.

First attempt to estimate the oIl spill hazard for the Algarve area, Southern Portugal, and its counties (assigned with their respective names).
Hazard values range from 0 (very low/absent hazard) to 1 (very high). Mapping relative to the year of 2013. Extracted from Sepp Neves et al., 2016
Histogram of oil concentrations found at the coasts generated by the Algarve ensemble experiment. The oil spill hazard and its uncertainties are estimated in GLAMOR based on the concentration distribution

The AtlantOS experiment setup

Here the details for the model setup for the oil spill hazard bulletin

  • —Release Point grid: 1/4deg
  • —Spatial coverage of RP grid: coastal band (30 – 130 km offshore) covering ice-free areas in the Atlantic
  • —Number of parcels for each oil spill simulation: 25,000 -representing 10,000 tonnes (accidental scenarios) and 1 tonne (operational scenarios)
  • —Oil API: 38
  • —Current fields: CMEMS Global ocean daily analyses (1/12deg)
  • —Wind fields: ECMWF ERA-Interim Reanalysis
  • —Wave fields: Stokes drift disregarded
  • —Temporal coverage: only 2013 for now
  • —Number of simulations to be performed: ~600,000 x 2