The ocean sustains life on this planet. It impacts all humankind in our increasingly global society. It dramatically affects climate systems and makes Earth a hospitable place to live. Coupled to the atmosphere, the ocean continually recycles air and water, purifying them in the process. It removes carbon dioxide from the atmosphere, buffering global change caused by human activities and an enhanced greenhouse effect. The ocean is a source of energy and resources, both living and non-living. It is a major repository of the world's biological diversity, and the potential source of a cure for diseases such as cancer and AIDS. It has been a source of wonder and inspiration throughout human history, inspiring art, music and some of the world’s great literature.

Earth’s human population began an exponential growth in the latter half of the 20th century.  Prior to this growth phase, the world’s oceans were thought to be a limitless source of seafood, and an infinite site for waste disposal. Today we are witnessing the limits of many of our ocean resources, but are still struggling with the illogic of poisoning such an important natural system. Thus, what initially began as natural use of the oceans, turned into overuse due to uncontrolled population growth, and then into misuse because of our ignorance of environmental impacts of our actions. Hampering our ability to take actions to reverse harmful environmental impacts are the priorities established by human use, which are economic and political. Optimistically, we are entering an age where we have the ability to representatively measure and model the ocean and terrestrial ecosystems, which is a prerequisite to developing a true understanding of changes occurring in the ocean ecosystem. At this time, we may not be able to put a value on what these truths hold, but with so many large-scale changes taking place, such information will be important for establishing the new human priorities, which are needed to protect the natural processes that sustain life on this Earth, our home.   

This is where Marine Science comes in. Marine Science (or Oceanography) is the scientific study of all aspects of the ocean environment. Marine scientists work to understand the ocean, its various environments and how they function. Using ships, submersibles, autonomous vehicles and satellites, marine scientists collect the information that is required to understand fundamental ocean processes. They study physical processes such as the motions of currents and waves, chemical processes such as the exchange of gases with the atmosphere and the cycling of nutrients, geological processes such as the formation of beaches and the origins of earthquakes and seafloor volcanism, and biological processes such as ocean productivity, larval recruitment and the role of microbes. Marine scientists have made tremendous progress in understanding how the ocean works as a coupled system. Still, many of the ocean's secrets remain hidden and the more we learn, the more we realize how much we still don’t know.

This text is not intended to be a comprehensive survey of the vast field of Marine Science. Rather it is hoped it will provide basic background and an introduction to key concepts that will be further developed in the classroom. One advantage of this digital format is that it allows you to follow links and view videos that will supplement and reinforce what you learn by reading. I encourage you to do so – there is an amazing world of online resources available that can make the oceans come alive for you. Welcome to Marine Science!