| Centers for Disease Control and Prevention, Climate Health Program
|
| Center for Heirs Property
|
| Center for Island Climate Adaptation and Policy
|
| Center for Limnology
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| Centers for Medicare & Medicaid Services
|
| Center for New York City Neighborhoods, Inc.
|
| Center for Planning Excellence
|
| Center for the Humid Tropics of Latin America and the Caribbean
|
| Central Council of Tlingit and Haida Indian Tribes
|
| Central Michigan University Institute for Great Lakes Research
|
| CERES (Clouds and Earth's Radiance Energy) Mission
|
| CH2M Hill (now Jacobs Engineering Group)
|
| Charles City County, VA
|
| Charleston Resilience Network
|
| Charlotte-Mecklenburg Storm Water Services
|
| Chemonics International Inc.
|
| Chesapeake Bay Foundation
|
| Chesapeake Bay Maryland Reserve
|
| Chesapeake Bay National Estuarine Research Reserve
|
| Chesapeake Bay Virginia Reserve
|
| Chevak Native Village Traditional Council
|
| Chicago Botanic Garden
|
| Chicago Metropolitan Agency for Planning
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| Chicago Region Trees Initiative
|
| Chicago Wilderness
|
