Summary Browse Data Disclaimer
Summary Browse Products are high-level pictorial representations of AIRS Instrument (AIRS Infrared, AMSU-A and HSB) data designed as an aid to ordering data from the GSFC DAAC or EDG. By viewing AIRS Browse images, users will find it easier to select science granules that correspond to features of interest. Some users may also find Summary Browse images to be useful tools in their own right. However, the following points should be considered.
Summary Browse Products represent a twice-daily global snapshot of AIRS Instruments observations for selected data channels,
one for ascending (daytime) nodes and one for descending (nighttime) nodes. The daily browse products will have gores between the satellite paths where there is no coverage for that day. Each summary browse product file consists of several unsigned 8-bit arrays. Each array is a 180 x 360 two-dimensional global map of the Earth's surface, at 1degree by 1 degree resolution, using a rectilinear projection where each grid cell is bounded by latitude and longitude lines. The longitudinal extent is from -180.0 degrees to +180.0 degrees, with the prime meridian in the center of the image. Each array element has a value between 0 and 255 and is a re-scaled representation of a floating-point number (visible images are integer).
The relationship between pixel value (pv) and input floating point data value (dv) is:
pv=(dv - minimum_dv)*(255/(maximum_dv - minimum_dv))+1 The files are in HDF RIS8 (8-bit raster) format and for each image within the file there is an associated color palette.
Additionally, for each image there are descriptive annotations in HDF DFAN format. The annotations consist of image title,
image description, and the minimum, mean, and maximum of the original data values and the corresponding pixel values.
The minimum and maximum of the original data values may be used to annotate a color bar.