August 7, 2010 - Phytoplankton bloom off Newfoundland

Phytoplankton bloom off Newfoundland

A milky blue swirl of phytoplankton floats in the Atlantic Ocean southeast of Newfoundland, Canada, in this true-colored image captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite on July 24, 2010.

The edges of the bloom, particularly on the southeastern side, appear green while the center of the bloom appears aquamarine to milky turquoise. The milky color may indicate the presence of coccolithophores, a type of phytoplankton that contains external plates of calcium carbonate. The long-term flux of these plates onto the ocean floors is the main process in the formation of chalk and limestone deposits.

Phytoplankton are microscopic single celled bacteria and algae that carry on photosynthesis. They not only form the backbone of the marine food chain, but they also extract carbon dioxide from the atmosphere and play a very important role in the balance of greenhouse gases. Although each organism is incredibly small, due to their vast numbers they not only color the seas, but they influence both the productivity of the ocean and the climate of the world.

The land mass to the north of the image is the Avalon Peninsula, part of Newfoundland island, and contains the Avalon Wilderness Reserve. The land forms a rolling plateau, dotted by boulders deposited by receding glaciers more than 10,000 years ago. The Reserve was set aside as a protected area for Woodland Caribou, Rangifer tarandus caribou, in the 1960s when only a few dozen of the animals remained on the island. The population now numbers in the several thousands.

The waters surrounding Newfoundland are known as the Grand Banks and are comprised of hundreds of miles of underwater plateaus and shallow water. The Grand Banks are known as one of the richest fishing grounds in the world, and are an ideal site for phytoplankton blooms. The banks, as they rise from the ocean floor, disturb deep ocean currents and cause the upwelling of nutrient rich water, which then mixes with the shallower, oxygen-rich water that overlies the plateaus. The combination of oxygen and nutrients allows life to thrive.

Image Facts
Satellite: Terra
Date Acquired: 7/24/2010
Resolutions: 1km ( B), 500m ( B), 250m ( B)
Bands Used: 1,4,3
Image Credit: Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC