Agriculture and Fisheries

The country's burden is also its lifeblood. Bangladeshis rely on the flooding to renew fish stocks, groundwater, and soil. Carrying two billion tons of fertile silt a year, the rivers help balance erosion, by forming new land through silt accretion.

"Sailors have known for centuries that the surface of the western Indian Ocean reverses its direction along with the winds of the seasonal monsoon. Oceanographers now have discovered that the reversal goes all the way to the sea floor, a phenomenon not known to occur anywhere else in the world.

Analysis of data collected on two scientific cruises of RRS Charles Darwin in the Indian Ocean is leading to a new understanding of the role of the monsoon in ocean productivity and global climate and of the evolution of ancient oceans. Using a combination of satellites and acoustic tracked floats and acoustic Doppler profiling from the ship. Their measurements of temperature, salinity and oxygen provided information about the mixing of deep and surface waters and the rates of circulation.

In addition to their discovery of the depth of the current reversal, they found that changes in circulation brought about by the monsoon were responsible for a surprising amount of productivity (blossoming phytoplankton).

This is one of the most productive open oceans anywhere. The winds of the summer monsoon produce up upwelling along the Somali coast and in the central Arabian Sea Deep water containing nutrients is brought to the surface. Without the monsoon, phytoplankton would have nothing to eat."

Phytoplankton- microscopic, single-celled ocean plants provide the ultimate source of food for marine life. If the upwellings cease the blooms of brown and green phytoplankton diminish and so do the fish, and with them the sea birds. This has a severe impact on the fishing industry.

(Monsoons Spur Sea's Productivity. USA Today, Vol:118, Iss: 241, June 1990, Page 2)