Hydrate-encrusted bubbles

Methane bubbles emerge from the seafloor and form translucent icy hydrate shells on the floor of the Gulf of America in 2014. The white surfaces are bacterial mats, which are common in areas of methane and sulfide emission. Bubbles are estimated to be a few centimeters in diameter. Methane emitted into the ocean is often oxidized to carbon dioxide in the water column, increasing the acidity and decreasing the oxygen content of ocean waters. Methane that reaches the atmosphere can contribute to global warming. Image courtesy of National Oceanic and Atmospheric Administration (NOAA) Ocean Exploration program.