USING LAKE SURFACE TEMPERATURE AND SYNTHETIC APERTURE RADAR (SAR) SATELLITE IMAGES OF LAKES SUPERIOR AND MICHIGAN ALONG WITH A3-DIMENSIONAL NUMERICAL MODEL OF LAKE SUPERIOR WE PROPOSE TO CHARACTERIZE AND UNDERSTAND THE SEASONAL EVOLUTION OF THE LATERALTHERMAL GRADIENT THAT DEVELOPS AROUND THE COAST OF THE LAKES AS THEY WARM DURING THE SPRING AND SUMMER SEASONS. THE THERMALGRADIENT COINCIDES WITH A STRONG DENSITY GRADIENT AND MARKS THE REGION OF STRONG SHEAR. IN OUR RECENT STUDY [MCKINNEY HOLT MATSUMOTO 2012] WHICH SERVES AS MOTIVATION FOR THIS PROPOSAL WE USED BOTH SAR AND SURFACE TEMPERATURE DATA OF LAKE SUPERIOR ANDDOCUMENT THE PRESENCE OF SMALL EDDIES AT SEVERAL LOCATIONS WITHIN THE LAKE IN ASSOCIATION WITH THE THERMAL GRADIENT. IN THIS PROPOSAL WESEEK AN IMPROVED UNDERSTANDING OF THE ROLES BOTH THE THERMAL GRADIENT AND EDDIES PLAY IN THE COASTAL CIRCULATION OF THE GREAT LAKESAND THE FORCING MECHANISMS THAT PRODUCE THESE FEATURES. THERE IS CONSIDERABLE SIGNIFICANCE OF THIS WORK WITH REGARD TO WATER QUALITYOF THE COASTAL REGIONS BECAUSE THE STRENGTH OF THE THERMAL GRADIENT IS BELIEVED TO CONTROL THE DEGREE TO WHICH WARM AND SOMETIMESPOLLUTED NEARSHORE WATERS MIX WITH COLD CLEAN OPEN LAKE WATERS. IT ALSO IMPACTS THE HEALTH OF COASTAL ECOSYSTEMS BECAUSE THE NEARSHOREWATERS SERVE AS NURSERY GROUNDS FOR JUVENILE FISH AND EARLY PLANKTONIC FORMS OF INVERTEBRATES. LAKES SUPERIOR AND MICHIGAN ARE TWOOF THE LARGEST GREAT LAKES IN THE WORLD. SITUATED IN THE MID-LATITUDES BOTH LAKES EXPERIENCE COMPLETE OVERTURNING IN THE FALL AND SPRING.THIS OCCURS AS LAKE TEMPERATURE MOVES PAST 4 C THE TEMPERATURE OF MAXIMUM DENSITY FOR FRESHWATER. OVERTURNING HOWEVER DOES NOTHAPPEN EVERYWHERE ALL AT ONCE. IN THE SPRING WARMING STARTS IN THE SHALLOW COASTAL REGIONS. WHILE THE OPEN LAKE IS STILL WINTER-LIKE ANDSURFACE TEMPERATURES ARE BELOW 4 C THE COASTAL MARGINS WARM TO ABOVE 4 C. WHERE THESE TWO WATERS MEET A THERMAL FRONT AND ZONEOF DOWNWELLING BECOME ESTABLISHED. THE BOUNDARY BETWEEN THESE TWO WATERS IS ALSO MARKED BY SHEAR AS THE DENSITY CONTRAST ACROSSTHE FRONTAL ZONE DRIVES COUNTERCLOCKWISE COASTAL CURRENTS. AS WARMING CONTINUES INTO THE SUMMER THE 4 C THERMAL FRONT MIGRATESOFFSHORE AND EVENTUALLY DISAPPEARS. WITH ADDITIONAL SURFACE HEAT FLUX VERTICAL STRATIFICATION BECOMES ESTABLISHED IN THE SUMMER.THERE IS SIGNIFICANT SPATIAL AND TEMPORAL VARIABILITY TO THESE PROCESSES EVEN WITHIN THE SAME LAKE. IN LAKE SUPERIOR THE NEARSHORETEMPERATURE GRADIENT PERSISTS THROUGHOUT THE SUMMER AND CONTINUES TO AFFECT THE COASTAL CURRENT. IN THIS PROPOSED WORK MULTIPLESATELLITE PRODUCTS WILL BE USED TO CHARACTERIZE HOW THE NEARSHORE THERMAL GRADIENT FORMS IN SPRING IN LAKES SUPERIOR AND MICHIGANAND FOLLOW ITS EVOLUTION THROUGH THE SUMMER SEASON. THE GRADIENT IS EXPECTED TO FORM IN VARIOUS LOCATIONS AT DIFFERENT TIMES OF THE YEARAND EVOLVE AT DISSIMILAR RATES. THESE OBSERVATIONS WILL BE INTERPRETED IN LIGHT OF PREVAILING CLIMATIC CONDITIONS AND GEOGRAPHIC FEATURES.A SIMILAR APPROACH WILL BE TAKEN WITH RESPECT TO EDDIES UNDER WHAT CONDITIONS ARE THEY FORMED INCLUDING WITH THEIR ASSOCIATIONWITH THE THERMAL GRADIENT HOW DO THEY EVOLVE AND WHAT IS THEIR RATE OF DISSIPATION. WE WILL ALSO USE OUR NEWLY DEVELOPED NUMERICALMODEL OF LAKE SUPERIOR TO SIMULATE THE SAME PHENOMENA. THROUGH A SERIES OF CONTROLLED NUMERICAL EXPERIMENTS THIS STUDY IS EXPECTEDTO IMPROVE OUR UNDERSTANDING OF CONDITIONS THAT FACILITATE AND DRIVE THE SEASONAL FORMATION AND EVOLUTION OF THE NEARSHORE THERMALGRADIENT AND EDDIES AND THE IMPACT ON COASTAL CIRCULATION AND TO ANTICIPATE POSSIBLE FUTURE CHANGES AND IMPACTS ON ECOSYSTEMS RELATEDTO CLIMATE CHANGE. WE CONSIDER THIS STUDY TO BE A PRECURSOR INVESTIGATION RELATED TO NASA'S FUTURE SURFACE WATER AND TOPOGRAPHY(SWOT) MISSION TO DETERMINE IF COASTAL CIRCULATION CAN BE MEASURED WITH THE SEA SURFACE TOPOGRAPHY CONCEPT OF SWOT AND THUS LEADTO A NEW SCIENCE INVESTIGA