OBSERVATION-BASED CHARACTERIZATION OF SURFACE RADIATION BUDGET INCLUDING THE SECULAR TREND AS WELL AS TEMPORAL AND SPATIAL VARIATIONS HAVE UNIQUE IMPORTANCE IN THE STUDIES OF PHYSICAL CLIMATE SCIENCE AND CLIMATE CHANGES. THE CERES-EBAF (ENERGY BALANCED AND FILLED) SURFACE RADIATION BUDGET PRODUCTS HAVE BEEN ONE OF THE MOST WIDELY USED SURFACE RADIATION BUDGET PRODUCTS. TO FIND RELIABLE AND MEANINGFUL WAYS TO IMPROVE AND VALIDATE THE ALGORITHMS USED IN THE PRODUCT IS ESSENTIAL TO THE CONTINUED EXCELLENCY OF THE DATA PRODUCTS. LEVERAGED ON THE PROGRESSES THAT WE HAVE MADE IN OUR PREVIOUS PROJECT FUNDED BY THE CERES TEAM WE PROPOSE TO UTILIZE LONGWAVE SPECTRAL RADIANCE OBSERVATIONS FROM AIRS (ATMOSPHERIC INFRARED SOUNDER) AND CRIS (CROSS-TRACK INFRARED SOUNDER) AS WELL AIRS RETRIEVAL PRODUCTS TO FURTHER STRENGTHEN THE TOP-DOWN CONSTRAINTS IN THE CERES EBAF-SURFACE ALGORITHM. SPECIFICALLY WE PROPOSE FOLLOWING SUB-TASKS FOR USING THE SPECTRAL RADIANCES OBSERVATIONS AND THEIR RETRIEVALS IN DIFFERENT WAYS TO SUPPORT THE CERES-EBAF SURFACE RADIATION PRODUCTS.