National/regional plots/animations of GASP (GOES Aerosol/Smoke Product) aerosol optical depth (AOD),
ta and channel 1 (visible channel) reflectance
Sample GASP ta plot
The Regional plots are defined by US EPA (Environmental Protection Agency) Regions,
with Regions 1-3 combined into one view. Regions 4-10 are separate plots.
The Regional plots show half-hourly GASP aerosol optical depth (in color contours) and half-hourly GOES channel 1 reflectance for cloud (in gray contours) during the sun-lit time.
GASP aerosol optical depth, ta
The GASP ta used for these plots is based on the GOES Aerosol/Smoke Product
(Knapp et al., 2002; Prados et al.,2007), which is derived from the visible channel of GOES
(Geostationary Operational Environmental Satellites)
imager. The retrieval algorithm runs near-real time with 30-minute interval during
sun-lit time and 4x4 km^2 spatial resolution at NOAA (National Oceanic and Atmospheric Administration) /NESDIS
(National Environmental Satellite, Data, and Information Service). The retrieved AOD is plotted on a scale of 0.0 to 1.0 with ta > 1.0 shown as dark red.
GOES channel 1 reflectance
The GASP cloud mask is derived from infrared channels 2 and 4 radiances. A ta is not derived for cloud filled pixels, therefore the clouds fields are represented by the channel 1 reflectance to help define synoptic weather features important to the movement of aerosols.
GASP data is being obtained from NOAA/NESDIS/Office of Research and Applications.
ReferencesPrint this page Close window
Knapp, K.R., T.H. Vonder Haar, and Y.J.Kaufman (2002), Aerosol optical depth retrieval from GOES-8: Uncertainty study and retrieval validation over South America, J.Geophys. Res., 107(D7), 4055, doi:10.1029/2001JD00505.
Prados, A.I., S. Kondragunta, P. Ciren, and K.R.Knapp (2007), GOES Aerosol/Smoke Product (GASP) over North America: Comparisons to AERONET and MODIS observations, J. Geophys. Res., 112, D15201, doi:10.1029/2006JD007968.