March 26, 2009 - Hydrogen Sulphide Eruptions Along the Coast of Namibia

Hydrogen ulphide Eruptions Along the Coast of Namibia

This image, acquired March 17, 2009 by the MODIS on the Aqua satellite, shows green swirls in the water, off the coast Namibia in Africa. The swirls look like a phytoplankton bloom but are actually hydrogen sulphide eruptions.

The conditions off the Namibian coast are the reason for this phenomena. Cold waters well up from deep in the ocean, replenishing nutrients at the ocean surface, often resulting in a rapid increase in marine plant life, like phytoplankton. The phytoplankton live just a few days, after which they sink and build up on the ocean floor, where they decompose with the help of bacteria.

One specific kind of bacteria gives off hydrogen sulfide gas which periodically bubbles up to the ocean surface; when it encounters more oxygen-rich water near the surface, a chemical reaction occurs that transforms the gas into pure sulfur. The mixture of the yellow sulfur and blue water make the water look green!

Image Facts
Satellite: Aqua
Date Acquired: 03/17/2009
Resolutions: 1km ( B), 500m ( B), 250m ( B)
Bands Used: 1,4,3
Image Credit: Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC