Distribution of oil concentration and oil mass in the Gulf of Mexico following the Deepwater Horizon oil spill simulated by the Connectivity Modeling System (CMS) using two-phase droplet and internal degassing parameterizations

The latest version of the oil application of the Connectivity Modeling System (CMS) or oil-CMS is used to run a series of far-field simulations of the Deepwater Horizon (DWH) blowout (2010-04-20) in the Gulf of Mexico. These simulations adopt a two-phase approach with methane gas and liquid oil in the same oil droplet, following the concept of “live oil” that features gas-saturated oil formed under deep-pressure low-temperature conditions, as during deep-sea blowouts. When the oil droplets rise in the water column, they experience an internal degassing process (Pesch et al., 2018), which affects their size, density, and surfacing speed. The model adopts a log-normal droplet size distribution at the initial release time (iDSD). The dataset contains the diagnostics and post-processing analysis from three experiments: 1) Two-phase experiment, no degassing parameterized; all gas formed in a rising oil droplet due to pressure-dependent solubility is released into ambient water. 2) Full degassing experiment, where all the gas formed due to solubility decrease remains inside the droplet; internal degassing takes place. 3) An experiment with size-dependent partial degassing, in which i) the droplets < 0.2mm lack an initial gas phase, ii) rising oil droplets from 0.2mm to 0.8mm experience a linear increase of internal degassing process and the corresponding linear decrease of the gas dissolution into the ambient water; iii) droplets > 0.8mm have predominantly internal degassing, so that /all gas remains inside the droplet and affects droplet density, size, and rising speed accordingly. The dataset includes daily averaged oil concentration in the top meter of the ocean, in the 800-1200 m layer just above the depth of the blowout, and the full 4-D domain; it also includes horizontally-cumulative oil concentration throughout the water column, the position and time information for oil which exited the system or landed, as well as trajectory information over a variety of time periods.