NEARLY 50% OF CANADA AND 80% OF ALASKA ARE UNDERLAIN BY PERMAFROST (PERENNIALLY FROZEN GROUND) BUT ARE PRECLUDED FROM FIELD STUDY OWING TO LOGISTICAL DIFFICULTY SHORT FIELD SEASONS AND HIGH COST. THE PRESENCE OF THIS PERMAFROST EXERTS FEEDBACKS ON SURFACE WATER ECOSYSTEMS AND THE ARCTIC BOREAL LANDSCAPE MOST OBSERVABLY IN THE FORM OF MILLIONS OF LAKES PONDS WETLANDS AND SATURATED SOILS WITH ASSOCIATED IMPACTS ON VEGETATION COVER GREENHOUSE GAS EMISSIONS SOIL CARBON SEQUESTRATION LANDSCAPE DISTURBANCE WILDLIFE HABITAT AND TRADITIONAL SUBSISTENCE ECONOMIES. THE PROPOSED PROJECT WILL STUDY THE RESILIENCE OF THESE SURFACE WATER FEATURES IN RESPONSE TO THAWING PERMAFROST CAPITALIZING ON THE LONG FLIGHT LINES OF THE NASA ARCTIC BOREAL VULNERABILITY EXPERIMENT (ABOVE) WHICH WILL SPAN A FULL SPECTRUM OF PERMAFROST CONDITIONS (PERMAFROST FREE TO CONTINUOUS PERMAFROST LOW TO HIGH GROUND ICE CONTENT) ECOSYSTEMS CLIMATIC REGIONS TOPOGRAPHIC RELIEF AND GEOLOGICAL SUBSTRATES. AT THE HEART OF THE PROPOSAL IS ACQUISITION AND STUDY OF NEW AIRBORNE DATA FROM AIRSWOT AN EXPERIMENTAL RADAR INTERFEROMETER SPECIFICALLY DESIGNED FOR SURFACE WATER STUDIES INCLUDING PRECISE DETERMINATION OF WATER SURFACE ELEVATIONS (WSES) FOR THOUSANDS OF LAKES PONDS RIVERS AND WETLANDS OCCURRING ALONG PLANNED ABOVE FLIGHT LINES. THE OVERARCHING SCIENCE QUESTION TO BE ANSWERED IS CAN PERMAFROST PRESENCE AND OR DISTURBANCE BE IDENTIFIED FROM REMOTE SENSING OF SURFACE WATER LAKE AND WETLAND ECOSYSTEMS. TWO SCIENTIFIC HYPOTHESES RELATING WATER SURFACE ELEVATIONS AND EXTENTS TO PERMAFROST AND ASSOCIATED LANDSCAPE DISTURBANCE WILL BE TESTED. TO ISOLATE THE INFLUENCE OF PERMAFROST FROM REGIONAL WATER BALANCE VARIATIONS THE VARIABLE INFILTRATION CAPACITY (VIC) WATER BALANCE MODEL WILL BE CALIBRATED ALONG THE ABOVE FLIGHT PATHS FOR USE BY THIS AND OTHER ABOVE PROJECTS. REMOTELY SENSED SURFACE WATER ELEVATIONS AND AREAL EXTENTS AND MAPPING OF VISIBLE MANIFESTATIONS OF PERMAFROST (E.G. THERMOKARST) ARE KEY TARGETS OF STUDY AND WILL BE OBTAINED USING THE AIRSWOT KA BAND INTERFEROMETRIC RADAR AND DIGITAL CIRRUS CAMERA (DCC) OPTICAL CAMERA IMAGERY AS WELL AS PLANNED ABOVE UAVSAR AIRMOSS AND LVIS AIRBORNE ACQUISITIONS AND ANCILLARY DATA PRODUCTS (PERMAFROST MAPS ARCTICDEM HIGH RESOLUTION DIGITAL ELEVATION MODEL). ANTICIPATED OUTCOMES OF THE PROJECT INCLUDE 1) FUNDAMENTALLY NEW SCIENTIFIC UNDERSTANDING OF THE INTERACTION BETWEEN PERMAFROST AND LAKE WETLAND WATER SURFACE ELEVATIONS IN THE ARCTIC BOREAL ZONE (ABZ); 2) IDENTIFICATION OF FOREST ECOSYSTEM DISTURBANCE LOCATIONS ATTRIBUTED TO PERMAFROST THAW ALONG ABOVE FLIGHT LINES; 3) ASSESSMENT OF THE POTENTIAL FOR USING REMOTELY SENSED WSE AND OR WSE CHANGES TO INFER THE PRESENCE ABSENCE OF SUBSURFACE PERMAFROST AND OR ATTRIBUTING ECOSYSTEM DISTURBANCE TO PERMAFROST THAW 4) NEW SYNERGIES BETWEEN ABOVE AND AIRSWOT SWOT DATASETS; AND 5) NEW SCIENCE AND DATA-SHARING COLLABORATIONS AMONG THE ABOVE SCIENCE TEAM. PI XXX AND COI XXX HAVE CAREER LONG EXPERTISE IN REMOTE SENSING AND FIELD STUDIES OF ARCTIC BOREAL HYDROLOGY AND CARBON CYCLES AND IN PLANNING AIRBORNE CAMPAIGNS IN REMOTE NORTHERN ENVIRONMENTS INCLUDING EXTENSIVE FIELD EXPERIENCE INSIDE THE ABOVE STUDY DOMAIN. COINVESTIGATOR XXX DEVELOPED THE VIC WATER BALANCE MODEL AND BRINGS DECADES OF NASA SCIENCE TEAM EXPERIENCE TO ABOVE. THE PROPOSAL IS HIGHLY RESPONSIVE TO SPECIFIC PRIORITIES OF ABOVE NASA AND NUMEROUS FEDERAL ENTITIES AND OFFERS MENTORSHIP OF GRADUATE AND UNDERGRADUATE STUDENTS AND COMMUNITY OUTREACH THROUGH SCIENTIFIC ENGAGEMENT WITH ELEMENTARY AND SECONDARY SCHOOLS IN ALASKA AND NORTHERN CANADA.