2.1: What is Oceanography

Until recent decades, oceanography was primarily an observational discipline with greater similarity to geography than to other sciences. For many thousands of years, study of the oceans was limited almost entirely to exploring and mapping the oceans, especially shallow underwater obstructions such as reefs. These studies were important to facilitate trade and travel between known landmasses and islands, but were very limited. Considerable information was also gathered about the best places to find fish and shellfish, especially in the coastal oceans. However, for many centuries this biological information was documented only in the oral histories of local fishers.

Aside from limited studies by scholars of a few ancient civilizations, almost all systematic studies of the oceans have been carried out within the past 250 years. During these two centuries, mapping of the oceans has continued with ever-increasing sophistication (Appendix 4). Geological oceanographers have mapped seafloor topography and sediments. Physical oceanographers have mapped distributions of salt content, temperature, and currents. Chemical oceanographers have mapped distributions of chemicals in seawater and in seafloor sediments. Biological oceanographers have mapped distributions of algae, bacteria, and animal species. Mapping the oceans has been an enormous task that is far from complete, for reasons we examine later.

During the past several decades, oceanographers have moved beyond simply mapping the ocean to studying ocean processes. As revealed in this text, the geological, physical, chemical, and biological processes in the oceans and overlying atmosphere are interdependent and complex. Consequently, oceanography must be interdisciplinary. Oceanography is now often called “ocean sciences” to acknowledge the discipline’s transition from primarily mapping oceans to interdisciplinary studies of ocean processes.

To perform their work properly, oceanographers must understand all basic ocean processes, although they often specialize in one aspect. In oceanography, much information must be integrated to describe complicated processes. Therefore, the scientist must take a step beyond many of the traditional sciences that rely on reductive methodology, in which investigators reduce the complexity of a problem by studying only part of it (e.g., studying the effect of varying temperature on a single species rather than the combined effects of all environmental variables and competition from other species). Oceanographers do perform reductive methodology experiments in controlled laboratory or field conditions but they must always integrate and compare them with detailed observations of the ever-changing marine environment. This integration and comparison often requires the use of computer models (CC10).