| College of New Jersey Sustainability Institute
|
| Colorado Basin River Forecast Center
|
| Colorado Department of Natural Resources Water Conservation Board
|
| Colorado Department of Transportation
|
| Colorado Energy Office
|
| Colorado Parks and Wildlife
|
| Colorado Springs Utilities
|
| Colorado State University
|
| Colorado State University Natural Resources Ecology Laboratory
|
| Columbia County Soil and Water Conservation District
|
| Columbia River Inter-Tribal Fish Commission
|
| Columbia University Center for Climate Systems Research
|
| Columbia University Earth Institute—Center for International Earth Science Information Network (CIESIN)
|
| COMET MetEd
|
| Commission for Environmental Cooperation
|
| Community Resilience Building
|
| Community Viz
|
| Computational Hydraulics International
|
| Confederated Salish and Kootenai Tribes
|
| Connect4Climate
|
| Connecticut Department of Energy and Environmental Protection
|
| Connecticut Sea Grant
|
| Consensus Building Institute
|
| Conservation Biology Institute
|
| Conservation International
|
