AMSU-A Level 1B data sample product
The AMSU-A level 1B data set contains AMSU-A calibrated and geolocated
brightness temperatures in degrees Kelvin. This data set is generated
from AMSU-A Level 1A digital numbers (DN), including 15 microwave channels
in the 50 - 90 GHz and 23 - 32 GHz regions of the spectrum. A day's worth
of data is divided into 240 scenes each of 6 minute duration. An AMSU-A
scene contains 30 cross-track footprints in each of 45 along-track
scanlines, for a total of 45 x 30 = 1350 footprints per scene. The AMSU-A
is co-aligned with the AIRS
instrument onboard the Aqua platform so that
successive blocks of 3 x 3 AIRS footprints are contained within the AMSU-A
footprint.
AMSU-A is primarily a temperature sounder that provides atmospheric
information in the presence of clouds, which can be used to correct the
AIRS infrared measurements for the effects of clouds. This is possible
because non-precipitating clouds are for the most part transparent to
microwave radiation, in contrast to visible and infrared radiation which
are strongly scattered and absorbed by clouds. Combined with simultaneous
measurements from the AIRS and HSB
instruments, the calibrated AMSU-A
brightness temperatures will also be used to initialize the surface
temperature and atmospheric temperature profile required for the retrieval
of the final AIRS geophysical products. AMSU level 1B daily summary browse
product is also available to provide users with a global quick look
capability when searching for data of interest.
GES DISC Data Access
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ESDT Shortname:
AIRABRAD
Coverage:
Global, Twice Daily
(Daytime and Nighttime)
Resolution:
40.5 km FOV at nadir
Spectral Range:
AMSU-A1: 13 channels from 50 - 90 GHz
AMSU-A2: 2 channels from 23 - 32 GHz
Volume:
0.6 MB/file, 240 files/day
Product Guide:
AIRS User Guide
Instrument Guide:
AMSU-A Instrument Guide
To plot AMSU brightness temperatures
on satellite projection:
(can save the image as well)
idl -novm -rt=airs1b_look.sav –args
filename channel_number(option)
AIRS.2003.07.13.060.L1B.AMSU_Rad.v5.
0.0.0.G07090194232.hdf 1
default channel=3 (50300.0 MHz)
amsuFrequency = [23800.0, 31400.0,
50300.0, 52800.0, 53596.0, 54400.0,
54940.0, 55500.0, 57290.0, 57290.0,
57290.0, 57290.0, 57290.0,
57290.0, 89000.0] MHz
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Atmos Composition
