AOD measurements from the MODIS (550 nm) instrument aboard the Terra spacecraft were compared with preliminary retrievals of AOD from the HSRL (532 nm) aboard the King Air B200. Initial comparisons were conducted on 12 and 13 March 2006, at which time the King Air B200 flight track intersected the ground track of the Terra spacecraft. AOD was derived from the HSRL measurements by integrating the aerosol extinction profiles between 0.1 and 7km. On 12 and 13 March, the correlation between HSRL and MODIS AOD values were 0.774 and 0.667 respectively. The two data sets were further analyzed using a neural network to provide a better comparison by adjusting the weights of data variation. After neural network analysis, the correlation increased to 0.796 (2.84%) and 0.858 (28.6%) respectively.
The HSRL and MODIS AOD measurements were also used to examine forecast simulations of AOD from the Sulfur Transport dEposition Model (STEM). Regression and correlation analyses were performed on AOD values for MODIS, HSRL and STEM. Visualizations were constructed to show trends among the three instruments over the time of flight. On 12 March, STEM correlated well with HSRL and MODIS (r = 0.979 and 0.744 respectively). On 13 March, the STEM forecasts correlated poorly with HSRL and MODIS (r = 0.013 and 0.059 respectively).
The potential use of measurements from future spaceborne sensors such as the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) onboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and the Aerosol Polarimetry Sensor (APS) instrument onboard Glory for similar studies will also be discussed.