MOULINS ARE VERTICALLY ORIENTED SHAFTS THAT THAT CARRY SURFACE MELTWATER TO THE BASE OF AN ICE SHEET WHERE IT JOINS THE SUBGLACIAL HYDROLOGIC SYSTEM AND MODIFIES ICE FLOW. THUS CONSTRAINING THE MECHANISMS CONTROLLING MOULIN FORMATION AND LONGEVITY ARE CRUCIAL TO UNDERSTANDING THE FUTURE EVOLUTION OF THE GREENLAND ICE SHEET WHERE SURFACE MELT EXTENT AND INTENSITY ARE PROJECTED TO INCREASE. HOWEVER PREVIOUS WORK HAS FOCUSED ON IDENTIFYING MOULINS IN SPECIFIC REGIONS TRACTABLE TO MANUAL OR SEMI-AUTOMATED REMOTE SENSING ANALYSES WITHOUT EXPLORING THE UNDERLYING FORMATION MECHANISMS LIMITING THE ABILITY TO CHARACTERIZE SPATIOTEMPORAL MOULIN DISTRIBUTION WITHOUT THE AVAILABILITY OF HIGH RESOLUTION IMAGERY.TO DATE GLOBAL CLIMATE MODELS (GCMS) GENERALLY PORT SURFACE MELT DIRECTLY TO THE OCEAN BYPASSING ITS TRANSPORT THROUGH MOULINS TO THE ICE-SHEET BED. BECAUSE MOULINS SWITCH WATER FROM FLOWING ACROSS THE ICE-SHEET SURFACE TO FLOWING ALONG THE ICE-SHEET BED THEIR INCLUSION IN THE NEXT GENERATION OF GCMS IS AN IMPORTANT RESEARCH FRONTIER. WITHIN ICE-SHEETS MOULINS MODULATE THE LOCATION TIMING AND VOLUME OF SURFACE MELT AT THE BED; THESE ARE PRIMARY CONTROLS ON THE SEASONAL EVOLUTION OF THE SUBGLACIAL HYDROLOGIC SYSTEM. THUS ACCURATE INCORPORATION OF MOULINS INTO ICE SHEET MODELS (ISMS) WITH SUBGLACIAL HYDROLOGY ROUTINES IS CRUCIAL TO CAPTURING OBSERVED SEASONAL VARIATIONS IN THE DYNAMIC COMPONENT OF ICE-SHEET MASS BALANCE. MOULINS ACT AS FILTERS BETWEEN THE SURFACE MELTWATER SUPPLY AND THE BASAL HYDROLOGIC SYSTEM AND AS SUCH MUST BE INCLUDED IN MODELS WITH THESE COMPONENTS. THIS PROJECT WILL COMBINE PROCESS-SCALE MODELING AND REMOTE-SENSING TECHNIQUES TO DEVELOP A STOCHASTIC MODEL FOR THE SPATIAL DISTRIBUTION AND TEMPORAL EVOLUTION OF MOULINS IN WESTERN GREENLAND. THE PROPOSED WORK WILL FIRST EXPAND AN EXISTING PHYSICAL MODEL FOR A WATER-FILLED CREVASSE INTO A MORE COMPLETE PHYSICAL MODEL FOR MOULIN INITIATION AND EVOLUTION ACROSS MULTIPLE TIMESCALES (MINUTES TO DECADES) INCLUDING REACTIVATION IN SUBSEQUENT YEARS. NEXT AN ANALYTIC MODEL FOR THE TRANSMITTANCE OF BASAL PERTURBATIONS TO THE ICE-SHEET SURFACE WILL BE COUPLED TO THE PHYSICAL MOULIN MODEL IN AN EFFORT TO CAPTURE THE OBSERVED CASCADING NATURE OF MANY MOULIN ACTIVATION EVENTS. THESE MODELS WILL BE INFORMED BY AND VALIDATED WITH REMOTE-SENSING DATA PRODUCTS INCLUDING GIMP ARCTICDEM LANDSAT MODIS MEASURES AND GOLIVE. FINALLY THE RESULTS WILL BE SYNTHESIZED INTO A STOCHASTIC MODEL THAT WILL CONSTRAIN THE SPATIAL DENSITY AND ACTIVATION DATES OF MOULINS IN CURRENT AND FUTURE CLIMATES. THE STOCHASTIC MODEL WILL BE DEVELOPED FOR USE IN ISMS AND IN GCMS TO IMPROVE THEIR SURFACE MELT RUNOFF SCHEMES. THE PROPOSED WORK WILL CONTRIBUTE (1) A MOULIN PARAMETERIZATION FOR ISMS AND GCMS FOR THE DELIVERY OF SURFACE MELT TO THE BED AND (2) AN ENHANCED UNDERSTANDING OF HOW WHERE AND WHEN MOULINS MAY DELIVER SURFACE MELT TO THE BED OF THE GREENLAND ICE SHEET IN FUTURE WARM CLIMATES. THE INVESTIGATION ADDRESSES GOALS OF THE ARCTIC STUDIES COMPONENT OF THE SOLICITATION INCLUDING DETERMINING THE CONNECTIONS BETWEEN GLACIAL DYNAMICS BED CHARACTERISTICS AND MELT WATER. THE PROJECT ALSO DIRECTLY ADDRESSES SPECIFIC LONGERTERM GOALS OF THE NASA CRYOSPHERE PROGRAM BY CHARACTERIZ[ING] LAND ICE PROPERTIES SUCH AS ENGLACIAL AND SURFACE WATER AND PHYSICAL PROCESSES SUCH AS MELT WATER FATE SUCH THAT THEY CAN BE INCORPORATED INTO MODELS. THE PRODUCT WILL BE DEVELOPED AS A FIRST STEP TOWARD USE IN GCMS AND ISMS IN COLLABORATION WITH RESPECTIVE EXPERTS FROM THE GLOBAL MODELING AND ASSIMILATION OFFICE AND THE CRYOSPHERIC SCIENCES LABORATORY AT NASA GSFC.