Organizing the Ocean

coastal scene

The Coastal and Marine Ecological Classification Standard is the first such system for marine ecosystems.

By Marguerite Huber

Do you like things alphabetized? In chronological order? Color coded? If so, you probably love organization. You probably have a place and category for every aspect of your life.

Well researchers from the National Oceanic and Atmospheric Administration, NatureServe, the U.S. Geological Survey, and EPA have taken organization to the next level. For more than a decade they have been working to organize the first classification standard for describing coastal and marine ecosystems.

This classification standard, called the Coastal and Marine Ecological Classification Standard (CMECS), offers a simple framework and common terminology for describing ecosystems—from coastal estuaries all the way down to the depths of the ocean. It provides a consistent way to collect, organize, analyze, report, and share coastal marine ecological data, which is especially useful for coastal resource managers and planners, engineers, and researchers from government, academia, and industry. The Federal Geographic Data Committee has already adopted CMECS as the national standard.

Organization at its finest, CMECS is basically a structure of classification, with the helpful addition of an extensive dictionary of terms and definitions that describe ecological features for the geological, physical, biological, and chemical components of the environment.

Using CMECS, you first classify the ecosystem into two settings, which can be used together or separately. The Biogeographic Setting covers ecoregions defined by climate, geology, and evolutionary history. The second, Aquatic Setting, divides the watery territory into oceans, estuaries and lakes, deep and shallow waters, and submerged and intertidal environments.

For both of these settings, there are four components that describe different aspects of the ecosystem, which are outlined in CMECS’s Catalog of Units. The water column component describes characteristics of, you guessed it, the water column, including water temperature, salinity, and more. The geoform component includes characteristics of the coast or seafloor’s landscape. The substrate component characterizes the non-living materials that form the seafloor (like sand) or that provide a surface for biota (like a buoy that has mussels growing on it). And finally, the biotic component classifies the living organisms in the ecosystem.

A benefit of CMECS’s structure of settings and components is that users can apply CMECS to best suit their needs.  It can be used for detailed descriptions of small areas for experimental work, for mapping the characteristics of an entire regional ecosystem, and for everything in between.  People reading scientific papers, interpreting maps, or analyzing large data sets can have clear and easily available definitions to understand the work and to compare results.

Additionally, it will be much easier to share data because CMECS allows everyone to use the same units and the same terminology. It is much easier to share and compare data when you’re using the same definitions and the same units!

Overall, with the use and application of CMECS, we will be able to improve our knowledge of marine ecosystems, while satisfying organizers everywhere.

About the authorMarguerite Huber is a Student Contractor with EPA’s Science Communications Team.

Editor's Note: The views expressed here are intended to explain EPA policy. They do not change anyone's rights or obligations. You may share this post. However, please do not change the title or the content, or remove EPA’s identity as the author. If you do make substantive changes, please do not attribute the edited title or content to EPA or the author.

EPA's official web site is Some links on this page may redirect users from the EPA website to specific content on a non-EPA, third-party site. In doing so, EPA is directing you only to the specific content referenced at the time of publication, not to any other content that may appear on the same webpage or elsewhere on the third-party site, or be added at a later date.

EPA is providing this link for informational purposes only. EPA cannot attest to the accuracy of non-EPA information provided by any third-party sites or any other linked site. EPA does not endorse any non-government websites, companies, internet applications or any policies or information expressed therein.