Monitoring dispersal patterns sea foam injected by offshore platforms using satellite optical multispectral imagery

Liquefied natural gas regasification plants can use seawater as a fluid in the process of converting gas from liquid to gas. In some cases, in correspondence with the discharge into the sea of the water used in the regasification process, "foams" may develop. In order to assist the overall evaluation of the phenomenon, an initiative was launched aimed at identifying foams with the use of satellite Earth observation data. Satellite optical multispectral imagery acquired by MSI sensor aboard Copernicus Sentinel-2 satellite constellation have been used to map areal distribution of sea foam generated from offshore platform and dispersed over sea. A sea foam detection procedure has been developed, including the following processing steps: i) cloud masking; ii) cloud mask refinement; iii) sea foam detection; iv) spatial filtering. Sea foam spatial patterns, identified from Sentinel-2 MSI satellite acquisitions in the period 2015-2022, have been complemented with information related to dispersal direction and maximum distance from platform discharge point, and related to sea state and weather conditions, specifically, wind, waves, currents, and rainfall data. Results showed that the proposed procedure is effective in sea foam dispersal patterns identification and can be extended to other high-resolution remote sensing imagery.