WE WILL DEVELOP A TEN-YEAR ARCTIC (60-90 N) THREE-DIMENSIONAL AEROSOL EXTINCTION AND OPTICAL DEPTH REANALYSIS PRODUCT FOR SUMMER MONTHS BASED ON NUMERICAL MODELING SIMULATIONS. APPLYING THIS PRODUCT WE WILL STUDY REGIONAL TRENDS IN SUMMERTIME ABSORPTIVE AEROSOL TRANSPORT TO/WITHIN THE ARCTIC AND CORRESPONDING AEROSOL DIRECT SURFACE FORCING AND PARTICLE MASS DEPOSITION TO INVESTIGATE CORRELATIVE RELATIONSHIPS BETWEEN REGIONAL AEROSOL PRESENCE AND SEASONAL SEA ICE MELTING. THE NOVELTY IN THIS WORK COMES FROM DEVELOPING A NEW DATA ASSIMILATION (DA) CAPABILITY FOR THE NAVAL AEROSOL ANALYSIS AND PREDICTION SYSTEM (NAAPS) BASED ON ADAPTING THE UNDER-UTILIZED OMI AEROSOL INDEX (AI) PRODUCT TO TRACK ULTRAVIOLET ABSORBING AEROSOLS (DUST AND SMOKE) REGIONALLY OVER BRIGHT SURFACES (ICE SNOW AND CLOUD). THE USE OF OMI AI WILL COMPLEMENT TRADITIONAL AEROSOL DA CONDUCTED WITH MODIS MISR AND CALIOP AEROSOL DATASETS THAT HAVE PROVEN EXTREMELY LIMITED NEAR THE POLES. THE TEN-YEAR PRODUCT WILL COVER 2007-2016 TO MATCH THE CONCURRENT AVAILABILITY OF ALL FOUR SATELLITE AEROSOL DATASETS WITH REGIONAL SUMMERTIME MONTHS (DEFINED HERE SIMPLY AS APRIL-OCTOBER) CHOSEN TO COINCIDE WITH THE AVAILABILITY OF EACH OF THE PASSIVE AEROSOL DATASETS INTRODUCED. CURRENT MODIS MISR AND CALIOP LEVEL 2 DATASETS ARE EXTREMELY LIMITED IN THE ARCTIC MAKING TRADITIONAL AEROSOL MODEL DA CHALLENGING AND DEGRADING REGIONAL MODEL SKILL OVERALL. MODIS AND MISR AEROSOL OPTICAL DEPTH (AOD) RETRIEVALS OVER BRIGHT SURFACES LIKE ICE SNOW AND CLOUD ARE VERY DIFFICULT. CALIOP RETRIEVALS ARE LIMITED BY COMPLICATIONS IN ISOLATING AEROSOL SCATTERING SIGNAL RELATIVE TO HIGH LEVELS OF MOLECULAR BACKGROUND SCATTERING NEAR THE POLAR SURFACE. WHEREAS THE UNPRECEDENTED VALUE IN NEWLY-AVAILABLE GLOBAL AEROSOL REANALYSIS PRODUCTS TO THE COMMUNITY IS QUICKLY BECOMING OBVIOUS THERE EXISTS A SIGNIFICANT KNOWLEDGE GAP IN THE ARCTIC AEROSOL SYSTEM THAT LESSENS MODEL FIDELITY FOR LAND-ATMOSPHERIC PROCESS STUDY IN THIS CRITICALLY-SENSITIVE DOMAIN. THE OPPORTUNITY TO TEST OUR HYPOTHESIS THAT DIRECT AEROSOL SURFACE FORCING TRENDS AND PROPERTIES ARE SIGNIFICANTLY INFLUENCING SEASONAL SEA ICE MELT IN THE ARCTIC IS THUS A COMPELLING INITIAL APPLICATION OF AN OMI AI-CONSTRAINED SUMMER REANALYSIS PRODUCT. TO CONDUCT A TEN-YEAR NAAPS MODEL RUN AND THUS DEVELOP THE ARCTIC SUMMER REANALYSIS PRODUCT PREREQUISITE TASKS WILL BE PERFORMED.WE WILL DEVELOP AND VERIFY A LEVEL 3 OMI AI DA-FRIENDLY DATA PRODUCT ACCOUNTING FOR ANOMALIES INDUCED BY CLOUD FRACTION VERTICAL AEROSOL PROFILE AEROSOL TYPE AND VIEWING ANGLE. A LEVEL 3 CALIOP AEROSOL PRODUCT WILL BE DESIGNED BASED ON RESAMPLING THAT OPTIMIZES SIGNAL-TO-NOISE AND INCREASES AEROSOL RETRIEVAL SKILL IN THE ARCTIC. AN OMI AI SIMULATOR FOR NAAPS WILL BE BUILT BASED ON WORK CONDUCTED WITH THE NASA GEOS-5 AEROSOL MODELING SYSTEM. JACOBIANS FOR OMI AI RELATIVE TO NAAPS AEROSOL MASS CONCENTRATION FOR UV-ABSORBING SMOKE AND DUST WILL BE DERIVED USING THE VLIDORT RADIATIVE TRANSFER MODEL. THE CURRENT NAAPS ASSIMILATION SYSTEM WILL BE ADAPTED TO PROCESS OMI AI. MODIS MISR CALIOP AERONET AND MPLNET DATASETS WILL BE USED AS NECESSARY TO CONDUCT THESE TASKS AND PROVIDE VERIFICATION CONTEXT. FURTHER A POTENTIAL SYSTEM VERIFICATION EXERCISE USING NASA AIRCRAFT OBSERVATIONS TENTATIVELY SCHEDULED FOR COLLECTION DURING THE 2017 ARCTIC SUMMER IS DESCRIBED.