An overview of J-31 aircraft measurements in the Megacity Initiative Local and Global Research Observations (MILAGRO) experiment

In March 2006 the J-31 flew a suite of instruments to measure solar energy in the atmosphere and how it is affected by aerosols, water vapor, clouds, and Earth surfaces. The goal was to better understand the impacts of these constituents and surfaces on climate and to advance spaceborne and airborne measurement science. The J-31 carried meteorological and navigational instruments, plus four core science instruments: Ames Airborne Tracking Sunphotometer (AATS-14), Solar Spectral Flux Radiometer (SSFR), Research Scanning Polarimeter (RSP), and Cloud Absorption Radiometer (CAR). Specific objectives were to: (1) Characterize aerosols and water vapor flowing from Mexico City and biomass fires toward and over the Gulf of Mexico, (2) Quantify the ability of satellites and airborne lidar to retrieve aerosol, cloud, and water vapor properties, (3) Characterize surface spectral albedo and bidirectional reflectance to help constrain satellite retrievals, (4) Quantify relationships between the above and aerosol amount and type. The J-31 made 13 flights (4 over Mexico City, 9 over the Gulf of Mexico) coordinated with the satellites Aura, Aqua, Terra, and Parasol. Several flights coordinated with the NASA Langley King Air B-200, which carried a High Spectral Resolution Lidar (HSRL) and two passive remote sensors. One flight coordinated with the DC-8 over Mexico City and one with both the C-130 and the B-200 over the Gulf of Mexico. We summarize goals, methods and sample results to provide context for other J-31 presentations at this conference.