LASE measurements of water vapor, aerosol, and cloud distributions during GRIP

The Lidar Atmospheric Sensing Experiment (LASE) system was deployed on the NASA DC-8 aircraft during the NASA GRIP (Genesis and Rapid Intensification Processes) field experiment, which was conducted during August and September 2010 from operational bases in Fort Lauderdale, FL and St. Croix, VI. The LASE system uses the differential absorption lidar (DIAL) technique to measure water vapor distributions over the entire troposphere using an injection seeded Ti:sapphire laser operating on a strong absorption line in the 815-nm band of H2O. LASE system was extensively upgraded before deployment on the GRIP mission. LASE operated in the nadir and zenith modes simultaneously and obtained profiles of water vapor, aerosols, clouds during 20 flights. Measurements were made over several storms including Hurricanes Earl and Karl and tropical storm Gaston. The data obtained by LASE on the DC-8 were used along with observations from dropsondes/radiosondes, and other ancillary information to retrieve more advanced data products like relative humidity, aerosol extinction profiles, and aerosol optical depth to conduct basic research related to hurricane development. These data provide information to characterize the moisture (low-to-mid level and dry air), thermodynamic environment, the Saharan Air Layer (SAL), cloud development, and environmental stability conditions. Examples of these measurements will be presented in this paper. Observations of moisture, aerosols, and cloud distributions associated with Hurricane Earl from multiple flights during August 30 to September 2, 2010 will be presented that show gradients of moisture across the storm, aerosol distributions in the boundary layer, cloud structure of the eye, cirrus associated with the outflow regions, and dry air associated with regions of subsidence. In particular, observations that show the evolution of the hurricane eye are presented from 6 crossings over the eye of Hurricane Earl on August 30, 2010 as this storm intensified from a category 2 to a category 4.