Coastal and Marine Ecological Classification Standard

The Coastal and Marine Ecological Classification Standard (CMECS) provides a comprehensive national framework for organizing information about coasts and oceans and their living systems. This information includes the physical, biological, and chemical data that are collectively used to define coastal and marine ecosystems.

CMECS is designed for use within all waters ranging from the head of tide to the limits of the exclusive economic zone, and from the spray zone to the deep ocean. It is compatible with existing upland and wetland classification standards and can be used with most if not all data collection technologies. Because of these characteristics, this standardization allows scientists to use and compare data from various sources and time frames.

CMECS Structure

CMECS classifies the environment into biogeographic and aquatic settings that are differentiated by features influencing the distribution of organisms, and by salinity, tidal zone, and proximity to the coast. Within these systems are four underlying components that describe different aspects of the seascape. These components provide a structured way to organize information and a standard terminology. The components can be mapped independently or combined as needed. 

The Sample Unit Gallery provides examples of various sites and how they would be classified using CMECS units. Each example shows a large-scale, ground view of the site with a location map and smaller-scale images to provide landscape context where appropriate. Additional samples will be added in the future. Users are encouraged to provide their examples to the CMECS Implementation Group.

In combination, the setting and component units can be used to identify biotopes, which are unique ecological units with biotic and abiotic elements.

The CMECS classification of settings and components that describe the seascape.

Examples of Components

CMECS Catalog of Units

The CMECS team has developed an on-line database of units, which users can search by keyword or browse to view each unit within a component. This database has been completed for the biogeographic and aquatic settings; the water column, geoform, substrate, and biotic components; and for all the modifiers. New units will be added to this database periodically as part of the normal CMECS update process.

The CMECS Partnership

CMECS is the result of an ongoing collaboration among several organizations. The principal developers of the standard are

  • NOAA’s National Ocean Service
  • NOAA’s National Marine Fisheries Service
  • NatureServe
  • U.S. Environmental Protection Agency
  • U.S. Geological Survey
  • University of Rhode Island

Representatives of these organizations collectively form the Implementation Group, which is the core of the current maintenance framework. A more formal maintenance body with broader representation will be established to advance CMECS’ use and manage updates to the standard. 

Additional Information

CMECS has been approved by the Federal Geographic Data Committee. The standard was developed, tested, and distributed for peer review over a period of several years by the NOAA Office for Coastal Management, NatureServe, and many other scientists and organizations, including the NOAA Office of Habitat Conservation, the U.S. Environmental Protection Agency, and the U.S. Geological Survey.

Federal Geographic Data Committee

Frequently Asked Questions

One-Page CMECS Description

Federal Geographic Data Committee Approval Process Presentation

Public Review Input to CMECS version 4

CMECS version 4 underwent an extensive public and peer review as part of the FGDC endorsement process. Check the link to examine the individual comments that helped shape the CMECS standard.

Contact Information

The CMECS Implementation Group is available for questions about the standard or to discuss opportunities to apply the standard to coastal management and research issues: