make it possible to predict the onset of an El Nino. Other 

 accomplishments include the development of new measurement 

 techniques, expansion of the existing data base, and the gathering 

 of considerable data on ocean fronts. 



Climate: Long-range Investigations, Mapping and Prediction 



CLIMAP, begun in 1971, is an investigation of oceanic conditions 

 during past ice ages. The primary data sources for the project are 

 the deep sea core libraries of our oceanographic institutions. Fossil 

 and geochemical evidence in these cores is used to infer past 

 oceanographic conditions. Since these libraries contain samples 

 from all areas of the world ocean, environmental charts for past 

 ages can be constructed. Hopefully these will lead to better under- 

 standing of the role of the oceans in past climates. 



Ocean surface conditions for the last ice age 18,000 years ago 

 have been reconstructed on a global basis, and used as input to 

 a numerical model to simulate the global climate at that time. 

 In addition, detailed climatic sequences for the past 250,000 years 

 have been reconstructed from a few cores representative of open 

 ocean conditions. 



International Southern Ocean Studies (ISOS) 



ISOS, initiated in 1974, is a new project aimed at understanding 

 the long-term, large-scale variability of dynamical processes in the 

 Southern Ocean, which is believed to play a significant role in 

 the ocean-atmosphere interactions that are so important to climate 

 and climatic change. A second goal of ISOS is to provide back- 

 ground information that will be useful in assessing the biological 

 productivity of the Southern Ocean, and its potential role in the 

 storage and distribution of ocean pollutants. 



The Seabed Assessment Program is directed toward better man- 

 agement of marine mineral exploration and exploitation. It consists of: 



South Atlantic Margins 



The continental margins are important economically. They con- 

 tain rich deposits of heavy minerals, sand and gravel in their 

 nearshore regions, and oil and gas further offshore. They also 



most productive in the world and is a major contributor to the world fishmeal 

 supply. El Nino is the occasional disruption of this system which occurs when warm, 

 nutrient-poor water spreads southward from the equator, displacing the cool, fertile 

 water of the Peru Current, severely impacting the bird and fish population (and the 

 anchovy harvest), and causing rain to fall on the parched Peruvian desert. Recently 

 it has been found that El Nino is only the coastal manifestation of a much larger- 

 scale process involving the entire system of equatorial currents in the Pacific. 



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