Journal article
GOES 8 retrieval of dust aerosol optical thickness over the Atlantic Ocean during PRIDE
Journal of Geophysical Research: Atmospheres, Vol.108(D19), pp.8595-n/a
10/16/2003
DOI: 10.1029/2002JD002494
Abstract
Using 30 days of half‐hourly, high temporal resolution GOES 8 imager data and radiative transfer calculations, dust aerosol optical thickness (AOT) was retrieved over the Atlantic Ocean (14°N ∼ 26°N, 73°W–63°W) during the Puerto Rico Dust Experiment (PRIDE). Dust aerosol size distributions and complex index of refraction inferred from ground‐based measurements (1.53–0.0015i at 0.55 μm), which were used in Mie calculations and a plane‐parallel discrete ordinate radiative transfer model (DISORT) to compute look up tables for AOT retrievals. Using a combination of spectral, spatial, and temporal tests, a dust detection algorithm was developed from the GOES 8 imager data. The degradation of the signal response relative to the prelaunched calibration of the GOES 8 visible channel was 39% in July 2000 and the GOES 8 AOT detection limit was estimated to be 0.04 in AOT (0.67 μm). The satellite‐retrieved AOT were then compared with AOT values derived from ground‐based Sun photometer (SP) sites. The comparison showed that GOES 8 retrieved AOT are in good agreement with the SP derived values, with linear correlation coefficient of 0.91 and 0.80 for the two sites. The GOES 8 monthly mean 0.67 μm AOT (0.19 ± 0.13, 0.22 ± 0.12) over the two SP sites matched the monthly mean SP AOT values (0.23 ± 0.13, 0.22 ± 0.10). The linear correlation between the GOES 8 retrieved AOT and the aircraft derived values from particle probe data and airborne Sun photometer AATS‐6 measurements were 0.88 and 0.83, respectively. Besides the uncertainties from the nonspherical effect of dust aerosols, sensitivity studies showed that the uncertainties (Δτ) of the GOES 8 retrieved AOT values were mainly from the uncertainties due to the imaginary part of refractive index (Δτ = ±0.05) and surface reflectance [Δτ = ±(0.02 ∼ 0.04)]. This paper demonstrates the application of geostationary satellites to detect and retrieve dust AOT even at low to moderate AOTs. The GOES 8 imager with high temporal resolutions also captures aerosol diurnal variation in this study that can further reduce the uncertainties in the current aerosol forcing estimations caused by the high temporal variations of AOT, thereby playing a complementary role with global AOT retrievals from polar orbiting satellites.
Details
- Title: Subtitle
- GOES 8 retrieval of dust aerosol optical thickness over the Atlantic Ocean during PRIDE
- Creators
- Jun Wang - University of Alabama in HuntsvilleSundar A Christopher - University of Alabama in HuntsvilleJeffrey S Reid - SPAWAR System CenterHal Maring - University of MiamiDennis Savoie - University of MiamiBrent N Holben - NASA Goddard Space Flight CenterJohn M Livingston - SRI InternationalPhilip B Russell - NASA Ames Research CenterShi‐Keng Yang - National Centers for Environmental Prediction
- Resource Type
- Journal article
- Publication Details
- Journal of Geophysical Research: Atmospheres, Vol.108(D19), pp.8595-n/a
- DOI
- 10.1029/2002JD002494
- ISSN
- 0148-0227
- eISSN
- 2156-2202
- Number of pages
- 15
- Language
- English
- Date published
- 10/16/2003
- Academic Unit
- Civil and Environmental Engineering; Physics and Astronomy; Chemical and Biochemical Engineering; Electrical and Computer Engineering
- Record Identifier
- 9984104907602771
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