Can Ship Design Stop Methane Emissions In Shallow Waters? - CleanTechnica

The article discusses a recent study from Communications Earth & Environment that highlights how ship traffic, particularly vessels traveling faster than 12 knots with hull drafts deeper than nine meters, can trigger significant methane emissions from organic-rich seabed sediments in shallow waters like Russia’s Neva Bay. This occurs due to the "squat effect," where the ship’s hull displaces water and creates a pressure drop beneath the vessel, causing methane bubbles trapped in sediments to be released into the atmosphere. The phenomenon is especially pronounced during warmer summer months when microbial activity increases methane production in sediments, and physical disturbances from ship movement prevent methane-consuming bacteria from oxidizing the gas effectively. While reducing ship speeds is a straightforward way to mitigate these emissions, the article explores alternative solutions involving ship design and propulsion technologies. Traditional large ferries with deep hull drafts and diesel engines connected to large propellers exacerbate the problem by generating significant pressure changes in shallow waters. Potential design improvements could focus on hull shapes and propulsion methods that minimize pressure fluctuations and sediment