Aircraft Profiles over Sun Photometers

Detailed vertical profiles were made above ground-based NASA sunphotometers for the purpose of obtaining the data required to carryout both internal and external direct aerosol radiative "closure" calculations.

Date (1995) Photometer site (lat / long) UW flight no. Time period of profile (hhmm UTC) Number of horizontal passes Ground instrumentation and measurements Comments on profiles Comments on ground measurements
27 Aug Cuiaba, over INPE building (15.6°S, 56.1°W) 1694 1929-2010 6 4 sunphotometers, 2 shadowbands, 2 pyranometer (optical depth, particle size distributions and phase function, spectral irradiance, sky radiance and sky polarization) Some thin cirrus. Possibly some capping Cu, but areal coverage minimal. Very uniform, thick smoke layer. (See Hobbs' Roll 4 photo #2 taken at 1926 UTC.) Few local sources; probably older smoke advected from north. Best coincident ground and aircraft data sets. ER-2 overpass at 1818 UTC. Aerosol size distributions and CCN spectra (U. Alaska) and aerosol size distributions, composition, and mass (U. São Paulo) at INPE.
30 Aug Pantanal (16.4°S, 56.6°W) 1696 1420-1543 13 3 sunphotometers, 1 pyranometer (optical depth, particle size distribution at 1730 UTC, sky polarization and spectral irradiance) Thin, broken altocumulus at ~12,000 ft; 30-50% areal coverage, and decreasing with time. (See Hobbs' Roll 4 photos #7 and 8.) Thick, uniform smoke layer. Possibly very thin haze layer aloft that aircraft did not reach. Clearing immediately after vertical profile. ER-2 overpasses at 1501 and 1524 UTC. Possible particle size distributions from inversions at 1600 UTC.
5 Sep Jamari, (9.2°S, 63.2°W) 1700 1931-2022 8 1 sunphotometer, 1 pyranometer (optical depth, sky radiance and solar irradiance) <25% Cu areal coverage. Dense, irregular smoke. No particle size distribution from inversions. Optical depth stable.
7 Sep Jamari (9.2°S, 63.2°W)
Repressa Samuel (8.8°S, 63.5°W)
1703 1605-1800 8 1 sunphotometer, sky radiance (optical depth, particle size distributions and phase function at 1514 UTC) ~30% altocumulus areal coverage, some (10%) cirrus at 40,000 ft. Cu popping up as time went on. More cloudy over Jamari site, less over Repressa Samuel. Numerous local fires mixing with regional haze. Numerous (deliberate) cloud penetrations during profile. ER-2 overpasses at 1657 and 1707 UTC. (See Hobbs' Roll 4 photos #20-23.) Ground data not coincident with aircraft profile. Optical depth not stable.
24 Aug Cuiaba, over INPE building (15.6°S, 56.1°W) 1692 1620-1638 Single spiral 2 sunphotometers, 1 shadowband (optical depth, particle size distribution, sky radiance, sky polarization and spectral irradiance) Cloud free. Patchy local smoke in relatively clean background air. (See Hobbs' Roll #1 photo #18.) Good optical depth. Aerosol size distributions and CCN spectra (measured by U. Alaska) and aerosol size distributions, composition and mass (measured by U. São Paulo at INPE).
1 Sep Pantanal (16.4°S, 56.6°W) 1697 1251-1419 12 3 sunphotometers (optical depth) Altocumulus coverage 70-100%. (See Hobbs' Roll 4 photo #11.) Thick, fairly uniform smoke layer. Overcast during aircraft profile, but clear between1420-1450 UTC. ER-2 1420 UTC) and LANDSAT 1300 UTC) overpasses. High resolution optical depth.
6 Sep Repressa Samuel (8.8°S, 63.5°W) 1701 1240-1308 1 1 sunphotometer (optical depth, particle size distribution, sky radiance and sky polarization) Altocumulus areal coverage 40-70%. Smoke in several distinct layers. Detailed profile over photometer site canceled. However, C-131 made gradual climb out from Porto Velho passing over site. Few observations from ground due to clouds.

Notes


Doug Burks
Last changed: 15 Apr 1996