THE SOUTHEASTERN US IS CHARACTERIZED BY GENERALLY ABUNDANT IN PRECIPITATION AND HIGH RADIATION INPUTS THEREFORE THE GROSS AND NET PRIMARY PRODUCTIVITY GPP AND NPP RESPECTIVELY OF THE REGION ARE HIGH MAKING IT A MAJOR CARBON SINK IN THE CONTERMINOUS US. NPP IS ALSO THE BASIS FOR FOOD AND FIBER PROVISION AND SUSTAINING VITAL ECOSYSTEM SERVICES. OVER THE LAST TWO CENTURIES THIS REGION HASEXPERIENCED A REMARKABLE DISTURBANCE HISTORY CHARACTERIZED BY WIDESPREAD CLEARCUTTING AND THEN REFORESTATION UNDER ACTIVE LAND MANAGEMENT THAT INCLUDES A FOCUS ON INTENSIVE FOREST MANAGEMENT. MORE RECENTLY THE COMBINATION OF HUMAN POPULATION GROWTH RAPID EXPANSION OF URBAN AREAS AND FOREST MANAGEMENT PRACTICE HAS RESULTED SIGNIFICANT LULC CHANGES IN MANY AREAS OF THE SOUTHEAST BUT ESPECIALLY IN THE PIEDMONT REGIONS AND ALONG SOME COASTAL AREAS. REGIONAL CARBON CYCLING IS UNDOUBTEDLY LINKED TO THIS MANAGEMENTHISTORY YET THE MECHANISMS BY WHICH HISTORICAL AND FUTURE LAND MANAGEMENT DECISIONS DETERMINE THE MAGNITUDE AND VARIABILITY OF THE REGIONAL CARBON SINK HAVE NOT BEEN ELUCIDATED. MOVING FORWARD THE ABILITY OF THE SOUTHEASTERN LANDSCAPE TO REQUESTER CARBON COULD BE SUBSTANTIALLY ALTERED BY CLIMATE CHANGES. FOR EXAMPLE THE REGION RECENTLY EXPERIENCED UNPRECEDENTED DROUGHTS IN 2001AND 2007 AND A SEVERE ICE STORM IN 2002 ALL OF WHICH SUBSTANTIALLY REDUCED THE PRIMARY PRODUCTIVITY IN THE REGION. ACCORDING TO THE MOST RECENT IPCC REPORT WE CAN EXPECT MORE FREQUENT AND SEVERE EXTREME WEATHER IN THE FUTURE WHICH COULD PROMOTE LARGE INTER ANNUAL VARIATION IN ECOSYSTEM PRODUCTIVITY AND ALTER DISTURBANCE REGIMES THAT COULD HAVE LONG LASTING IMPACTS ON THE PRIMARYPRODUCTIVITY AND CARBON SEQUESTRATION HOWEVER OUR CURRENT UNDERSTANDING OF SUCH IMPACTS ON GPP AND NPP ARE POORLY. TO BETTER QUANTIFY AND UNDERSTAND THESE IMPACTS WE WILL USE THE RICH REMOTE SENSING DATA AVAILABLE FOR THIS REGION THAT INCLUDE HISTORICAL AIR PHOTOS LONG TIME SERIES OF LANDSAT IMAGERY RECENTLY COLLECTED LIDAR MODIS AS WELL AS SENTINEL 2 FROM ESA. THE REMOTELY SENSED DATA WILL BE USED SYNERGISTICALLY TO RECONSTRUCT THE LULC CHANGE THROUGH TIME INCLUDING CHANGES IN LULC CATEGORIES AS WELL ASSPECIES COMPOSITION AS A RESULT OF FOREST SUCCESSION. THE LULC HISTORY RECONSTRUCTED FROM REMOTE SENSING WILL BE USED AS INPUT TO AN ECOSYSTEM PRODUCTIVITY MODEL TO DISAGGREGATE THE IMPACTS OF CLIMATE AND LULC CHANGES ON PRIMARY PRODUCTIVITY RESPECTIVELY. WE WILL USE US FOREST SERVICES FOREST INVENTORY ANALYSIS AMERIFLUX DATA AS WELL AS THE HIGH QUALITY STREAM FLOW DATA FROM USGS FOR MODEL CALIBRATION AND EVALUATION. WE INTEND TO ADDRESS THE FOLLOWING QUESTIONS 1 WHAT ARE THE HISTORICAL TRENDS IN THE PATTERNS OF LULC AND SPECIES COMPOSITION IN US SOUTHEAST SINCE THE 1950S? 2 HOW HAVE THE CHANGES IN FOREST EXTENT AND COMPOSITION ALTERED GROSS AND NET PRIMARY PRODUCTIVITY? 3 HOW AND TO WHAT EXTENT DOES THE COMBINATION OF THE HISTORICAL TRENDS IN CLIMATE AND LCLU IMPACT THE VULNERABILITY OF CARBON STORAGE IN THE SOUTHEAST IN THE PAST AND IN THE FUTURE? ANSWERS TO THESE QUESTIONS ARE CRITICAL FOR SUSTAINABLE DEVELOPMENT PLANNING IN THIS REGION GIVEN THE HIGH ECOLOGICAL AND ECONOMIC IMPORTANCE OF SOUTHEASTERN U.S. FOREST ECOSYSTEMS.