Plume off the Coast of South Africa

Plume off the Coast of South Africa

On April 10, 2003, the waters off western South Africa were showing swirls of green, while on land, several fires (red dots) were detected. North of South Africa, it is common for yellowish-green plumes to indicate hydrogen sulfide gas bubbling up from sediments on the sea floor. (As gas wells up, it reacts with oxygen dissolved in the water, producing pure sulfur, which is yellow). Whether this plume is indeed sulfur or simply a normal bloom of marine plants called phytoplankton cannot be determined without more detailed analysis or on-the-ground observations.

Image courtesy Jesse Allen, based on data from the MODIS Rapid Response Team at NASA GSFC