Every spring the waters of the Arabian Sea begin swarming with microscopic life. Tiny plants called phytoplankton, the base of the marine food chain, grow in the sunlight provided by the lengthening days. This image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows the amount of chlorophyll (proportional to the number of phytoplankton) on March 1, 2003. Ongoing dust storms in the area may be providing nutrients to spur the phytoplankton growth, but at some times of year dust and other aerosols prevent growth because they shade the ocean surface.

Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE