RECENT STUDIES CLEARLY SHOW THAT INLAND WATERS NOT ONLY TRANSPORT C FROM LAND TO COAST BUT ALSO INTERNALLY PRODUCE NEW AND MODIFY C AND ACT AS SIGNIFICANT C SINKS AND SOURCES. HOWEVER OUR UNDERSTANDING AND QUANTIFICATION OF C STOCKS AND FLOWS OF AQUATIC ECOSYSTEMS IS SUBJECT TO LARGE UNCERTAINTIES. FOR EXAMPLE THE CURRENT ESTIMATES OF C FLUXES SOURCES AND SINKS (E.G. TERRESTRIALLY-DERIVED C BURIAL AND OUTGASSING) OF NORTH AMERICAN AQUATIC ECOSYSTEMS ARE SUBJECT TO AN UNCERTAINTY OF 100%. FURTHERMORE THE COMPONENTS OF THE TERRESTRIALLY-DERIVED C THAT ENTERS INLAND WATERS ARE VERY POORLY CONSTRAINED. THE LARGE UNCERTAINTIES OF AQUATIC C BUDGETS IMPEDE RELIABLE MONITORING AND EFFECTIVE MANAGEMENT OF C IMPORTANT TO HUMAN SUSTAINABILITY. THEREFORE OUR GOAL IS TO DEVELOP AND TEST AN AQUATIC ECOSYSTEM CARBON MONITORING SYSTEM (AECMS) THAT INTEGRATES NASA REMOTE SENSING DATA IN SITU MEASUREMENTS AND PROCESS-BASED MODELING TO MONITOR MAJOR ORGANIC C (OC) FLUXES AND STOCKS OF INLAND WATERS.