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responsible for the large-scale fluctuations in the ocean and atmosphere in the mid-latitudes of the Pacific. Once underway, the NORPAX oceanographic-meteorological observation program will rely on data obtained from oceanographic ships, ships of opportunity, synoptic observations, aircraft, moored and drifting buoys, island stations, and satellites.

Another IDOE project, Climate-Long-Range Investigation, Mapping, and Prediction (CLIMAP), seeks to increase accuracy in environmental prediction by improving our understanding of past climatic conditions. Defining global changes on a continuous time scale for hundreds of thousands of years is important for several reasons. First, it may reveal for the first time the actual series of events during the transition between what are currently considered the two stable states of global climate, the ice age and the temperate age. Second, knowledge of the nature of the transitions is critical for building models of global oceans and climate. Finally, if the mechanisms of natural climate changes are not understood, then it becomes virtually impossible to assess or anticipate the effect of man's activity on the global environment.

CLIMAP researchers, through the study of deep-sea sediments, will examine changes in circulation patterns and water mass. properties in the world oceans during the Quaternary, the current geological epoch. The goal of CLIMAP is to determine in detail the surface ocean climatic fluctuations associated with glacial and interglacial transitions. Plans are to make four oceanographic maps showing sea surface temperatures from: (1) 6000 years ago, the warmest post-glacial period; (2) 17,000 years ago, the last glacial stage; (3) 120,000 years ago, the last interglacial period; and (4) 700,000 years ago, the mid-Pleistocene base. Contemporary sea surface maps provide the basis for historical comparisons.

Researchers participating in the Geochemical Ocean Sections Study (GEOSECS) are gathering chemical data on a large number of substances in deep ocean water. These data are essential for determining the rates at which pollutants will mix and diffuse in the deep ocean. GEOSECS scientists are making detailed measurements of oceanic constituents at selected depths along Arctic to Antarctic sections to provide for the first time a set of physical and chemical data measured on the same water samples. In addition to establishing geochemical baselines, these data will provide a basis for quantitative studies of oceanic mixing and for descriptive models of ocean circulation. The Atlantic phase of GEOSECS was completed in March 1973, and the Pacific phase is scheduled to begin in June 1973.

The IDOE is also supporting studies of coastal upwelling. Upwelling occurs when the effects of favorable winds, coupled with those of the earth's rotation, produce an offshore drift of surface layers of the sea along the coast. This induces an upwelling of

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nutrient-rich deeper waters to the surface, which results in a rapid growth in the plankton population and subsequently a high level of fish feeding on that food source. An estimated 50 percent of the world's fish supply comes from major upwelling areas. The main objective of the Coastal Upwelling Ecosystems Analysis (CUEA) program is to understand the coastal upwelling ecosystems so that the response of the system to change may be predicted from monitoring a few key biological, oceanographic, or meteorological variables. Field experiments on the physical and biological aspects of upwelling were conducted at two sites off the west coast of North America during 1972. The results of these investigations and the scientific teams involved are providing the basis for a multidisciplinary investigation of upwelling to be conducted off the coasts of the United States, Africa, and South America during 1973 and 1974.

Under the IDOE Seabed Assessment program, the Atlantis II of the

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Schematic View of Coastal Upwelling. When favorable winds exist, blowing toward the equator, the earth's rotation produces an offshore Eckman drift of the upper ocean layers along the coast. This drift in turn produces an upwelling of colder, deeper waters near the coast, often a narrow band 10 to 15 km wide. The rich nutrients of the upwelled deeper water cause a rapid growth in the plankton population which results in a rich feeding ground for fish. This phenomenon is significant because an estimated 50 percent of the world's fish supply comes from major upwelling areas.

Woods Hole Oceanographic Institution completed the first half of its survey of the Southeast Atlantic Margin from South Africa to Zaire in 1972. In January 1973, the ship began the second half of this survey, which will be completed later in 1973 with some measurements as far north as Portugal and as far west as the Mid-Atlantic Ridge. These last sets of measurements will enable scientists to tie the results of this survey to those of a complementary survey of the continental margins of the southwest Atlantic off the east coast of South America, which was also initiated in 1972. Scientists from institutions in many European, African, and South American countries participated in both surveys.

Site surveys for the Mid-Atlantic Ridge Study were initiated in 1972, conducted in large part by United States and French institutions, with additional aid from institutions in Canada, the United Kingdom, Iceland, and Portugal. In the Pacific, a comprehensive Nazca Plate survey was launched off the northwest coast of South America. This survey is concentrating on the active margins of the

plate in order to achieve a better understanding of the processes by which ore deposits originate. An international workshop on ferromanganese nodules on the ocean floor was convened under IDOE in New York in January 1972 to assess the present state of our knowledge in this area. As a result of this meeting, substantial quantities of existing data are being compiled for comparison and publication prior to the initiation of new laboratory and field investigations.

In addition, the NSF's Office of Polar Programs supports the Arctic Ice Dynamics Joint Experiment (AIDJEX). Understanding arctic ice and weather conditions is critical for developing the predictive capability necessary for future marine transportation in arctic waters. AIDJEX is a meteorological and oceanographic study of the strength and dynamics of pack ice and the interaction of air and sea in the Arctic Basin. The main goal is to understand the driving effects of wind and ocean currents on the pack ice so that it will be possible to predict the motion and deformation of sea ice into pressure ridges, leads, and large open-water areas. During March and April 1972, the second AIDJEX pilot study was performed on sea ice 300 miles north of Point Barrow. Three manned and five unmammed stations gathered data and allowed evaluation of instruments and techniques that will be used in the main experiment in 1975.

The Deep Sea Drilling Project (DSDP), the major activity of NSF's Ocean Sediment Coring Program, continued last year. Since 1968 the drilling ship Glomar Challenger has conducted its history-making expeditions to explore the deep ocean's sediment floor. Leg 28 of the ' project, conducted over the past year, was the first drilling operation in high latitudes, progressing from Freemantle, Australia, to Christchurch, New Zealand. Analysis of the data indicates that Antarctic glaciation began some 20 million years ago instead of the six or seven million years ago formerly assumed. The ice appears to have reached its maximum extent five or six million years ago, then rapidly receded to its present limits. Other findings were that Australia had broken away from Antarctica some 50 to 55 million years ago. Plans for the coming year include drilling in the western Pacific, then returning to Valparaiso, Chile. The project leaders hope to achieve deeper penetrations of the oceanic crustal structure.

The International Field Year for the Great Lakes (IFYGL), a major cooperative research undertaking of the United States and Canada, completed its field work in and around Lake Ontario during the year and moved into its data-analysis phases. U.S. support for this program is provided by NOAA, EPA, and NSF. A comprehensive international system has been established to process, archive, and disseminate the IFYGL data using two IFYGL Data/Computer Centers, one at the Canadian Centre for Inland Waters in Burlington, Ontario, and other at NOAA's Center for Experiment Design and

Data Analysis in Washington, D.C. These facilities are working with individual investigators to ensure that all data are recorded and available in appropriate forms.

IFYGL data analysis began during the year in eight major areas of study-terrestrial water budget, lake heat balance, water movement, atmospheric water balance, atmospheric boundary layer, evaporation synthesis, lake chemistry and biology, and simulation. Altogether there are 75 American and 81 Canadian tasks. Several models to describe and predict processes occurring in Lake Ontario are under development or test and evaluation. The ultimate aim of IFYGL is to develop an information base and models that will be useful in assessing the environmental impact of various alternatives for developing the resources and controlling pollution of the Great Lakes.

The Marine Resources Monitoring, Assessment, and Prediction program (MARMAP) is a nationally coordinated program of NOAA's National Marine Fisheries Service to monitor, assess, and predict the kinds and quantities of living marine resources available to the people of the United States, and to provide a comprehensive data base for domestic and international management of these re

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The 1972 MARMAP cruises to assess the distribution of fish eggs and larvae found widespread contamination of surface waters by oil residues. Over half of the plankton samples collected in surface layers contained clumps of tar.

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