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Trước khi bắt đầu một cuộc thảo luận về nguồn gốc và cấu trúc của các đại dương của thế giới, một trong những đầu tiên phải suy nghĩ về những lý do cho sự quan tâm của chúng tôi trong các cơ quan của nước, bao gồm khoảng bảy mươi phần trăm diện tích bề mặt của trái đất. Có lẽ một trong những lý do rõ ràng hơn là sự giàu có to lớn của nguồn tài nguyên thiên nhiên ẩn trong sâu thẳm của đại dương, bao gồm cả dự trữ lớn các nguồn thực phẩm và. | O OCEANOGRAPHY INTRODUCTION Before beginning a discussion of the origin and structure of the world s oceans one should first reflect on the reasons for our interest in these bodies of water which together comprise approximately seventy percent of the earth s surface area. Perhaps one of the more obvious reasons is the enormous wealth of natural resources hidden in the oceans depths including vast reserves of food and energy sources. This abundance has of course led to an increased human presence in and along much of the world s oceans prompting considerable concern for the short and long term consequences of man s activities in this fragile environment. An additional focus of recent oceanographic research has been the role of the sea in global climate variations spurred by the recognition that these variations are driven largely by fluctuations in the air-sea momentum and heat exchange. This role was dramatically illustrated in the 1982-1983 El Nino event which sparked such wide-ranging weather aberrations as flooding in southern California and droughts in Australia and is widely believed to have had an oceanic origin Rienecker and Mooers 1986 . In addition to these varied and multi-disciplinary research activities the increasing strategic importance of the world s oceans has been one of the prime motivations behind recent advances in underwater communication depth measurement and perhaps most significantly the remote sensing of ocean physical processes. In the political forum this strategic importance along with the economic benefits of the natural resources mentioned earlier continues to provoke international debate over such issues as fisheries management ocean dumping and the demarcation of territorial exclusive zone boundaries. Clearly therefore the oceans mean many different things to many different people. The common thread is the need and desire to learn more about these fascinating and fundamentally important bodies of water. In the following we shall .
