A Local Ensemble Transform Kalman Filter (LETKF) assimilation system has been implemented to a new type of ultra-high resolution aerosol-coupled global cloud resolving model called the Nonhydrostatic Icosahedral Atmospheric Model or NICAM to perform an experimental aerosol reanalysis. The Level 3 filtered, corrected, and aggregated MODIS AOD based on MODIS Level 2 aerosol product using the standard Collection 5 MODIS AOD algorithm are used to test the assimilation system. A posteriori AOT reduced the RMSD between MODIS AOT by 29.7% compared to a priori AOT. © 2013 AIP Publishing LLC.