NASA GIFTS Measurement Concept Overview 4th Workshop on Hyperspectral Science (MURI, GIFTS, GOES-R) University of Wisconsin

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NASA GIFTS Measurement Concept Overview4th
Workshop on Hyperspectral Science (MURI, GIFTS,
GOES-R)University of Wisconsin Madison (April
27-28, 2004)
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20/20 Vision (Weather in Our Palm)
By the year 2020, mankind will have the
technology (observations and models) to digitize
the earths surface and its atmosphere with a
resolution of 1 km and 1 minute And Every
individual on earth will have personal and
timely access to weather observations and
accurate weather forecasts through a palm
computer/display unit.
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2020 Vision Strategy
Surface-based Remotely Sensed
Integrated Data Products
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Environmental Satellites
FY POLAR (China)
FY GEO (China)
ENVISAT (Europe)
EOS (USA)
ADEOS (Japan)
NPOESS (USA)
METOP (Europe)
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Hyperspectral Atmospheric Sounder Evolution
Aircraft NAST-I / SHIS (1995 - )
Nimbus 3 4 IRIS/SIRS (1969-1972)
Nimbus 5/ITPR ITOS/VTPR Nimbus 6/NOAA
HIRS GOES/VAS HIRS (1972-2009)
High Resolution Interferometer Sounder
(HIS) (1985- )
Hyperspectral Resolution
Hyperspectral Resolution Imagery
First Satellite Sounders
High Horizontal Resolution
NMP GIFTS GOES-HES (20??- )
NPP/NPOESS/CrIS (2006- )
METOP-IASI (2005- )
ADEOS IMG (1996-1997)
Aqua AIRS (2002- )
FTS
Grating
Geostationary Imaging 4-d T,q,V Sounder
European Hyperspectral Resolution Sounder
US Hyperspectral Resolution Sounder
First Satellite Hyperspectral Resolution
Sounding Spectrometers
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Hyperspectral Atmospheric Sounding
The Infrared Radiance Spectrum
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AIRS Hyperspectral Atmospheric Slicing
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Hyperspectral Imaging
4.3 µm (2314 cm-1) CO2 Absorption Band
(3.0 µm)
(5.0 µm)
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Objective of the Geo-Sounder - Water Vapor
Motion
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Geostationary Imaging Fourier Transform
Spectrometer
New Technology for Atmospheric Temperature,
Moisture, Chemistry, Winds
EO-3 GIFTS
4-d Digital Camera
Horizontal Large area format Focal Plane
detector Arrays
Vertical Fourier Transform
Spectrometer

Time Geostationary Satellite
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GIFTS Sampling Characteristics

• Two 128x 128 Infrared focal plane detector
  arrays with 4 km footprint size
• Two 512 x 512 Visible focal plane detector
  arrays with 1 km footprint size
• Field of Regard 512 km x 512 km at satellite
  sub-point
• Ten second full spectral resolution integration
  time per Field of Regard
• 80,000 Atmospheric Soundings every minute

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GIFTS IR Measurements and Products
(8.8 to 14.6 microns)
(4.4 to 6.1 microns)
Products Water vapor (soundings, fluxes,
winds) Temperature (sounding, stability) Carbon
monoxide concentration (2 Layers) Ozone
concentration (4 Layers) Surface Temperature and
emissivity Clouds (altitude, optical depth,
microphysical properties, winds) Aerosol
Concentration and Depth
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NAST-I Validates GIFTS Concept

• Instrument Characteristics
• infrared Michelson interferometer
• (9000 spectral channels)
• 3.5 16 microns _at_ 0.25 cm-1
• Aircraft Accommodation
• ER-2 Super pod Proteus Underbelly pod
• Radiative Measurement Capability
• calibrated radiances with
• 0.5 K absolute accuracy, 0.1 K precision

Spatial Resolution 130m/km flight alt. (2.6 km
from 20km) Swath Width 2 km /km flight alt. (40
km from 20 km)
Temperature (K)
Water Vapor Mixing Ratio( Uncorrected)
Relative humidity ()
Tracks over ARM-site
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Wind Measurement
dt35 min
NAST-I Water Vapor Tracking Demonstrates GIFTS
Wind Profiling Technique
60 km x 40 km
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ER-2 NAST H2O Vs Twin Otter Doppler LIDAR Winds
Direction (Degrees)
270
360
0
90
180
700
February 11, 2003
36N, 121.6W
Off California Coast
800
GOES - IR
Pressure (mb)
900
X
1000
0
4
8
12
16
20
Speed (mps)
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Geostationary Hyperspectral Measurements

• Observation Capability Will Revolutionize
• Weather Forecasting
• Hurricane landfall (steering wind profiles)
• Tornadic storms (stability change monitoring)
• Nowcasting (rapid measurement update)
• Numerical prediction (initial p,T,q,V data)
• Air quality forecasts (O3 and CO transport)

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What About Clouds ????
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Cloud Effects on Retrieval
Non-opaque Clouds
Non-opaque Clouds
Opaque Clouds
NAST I-HOP June 12, 2002 Over Oklahoma
Cloud Tops
Moist Layers
Cloud Tops
PBL Ht
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Cirrus Cloud Venetian Blind Effect
Depressions due to Cloud Attenuation
16.0 UTC
13.8
Temperature (K)

14.9
Log10VMR (g/Kg)
These retrievals, uncorrected for cloud
attenuation, demonstrate the ability of a high
spatial resolution sounder to sense the spatial
structure of moisture below a scattered and
semi-transparent cirrus cloud cover
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Basis for Cloud Training Algorithm!
Radiance Spectra Carry Information on Cloud
Phase and Microphysical Properties
Wavenumber (cm-1)
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Cloud Retrieval Training !

• Perform a realistic simulation of clouds for
  synthetic EOF radiance training
• Diagnose cloud layer from radiosonde relative
  humidity profile
• A single cloud layer (either ice or liquid) is
  inserted for the highest level of cloud diagnosed
  from the input radiosonde profile. If a second
  cloud layer exists it is represented as an opaque
  cloud.
• Use parameterization of Heymsfelds balloon
  and aircraft cloud microphysical data base
  (2003) to specify cloud effective particle
  radius, re, and cloud optical depth, ?, (i.e.,
  re a ?? / ? - b??) .
• Different habitats can be specified (Hexagonal
  columns assumed here)
• Different clouds microphysical properties
  simulated for same radiosonde using random number
  generator to specify visible cloud optical depth
  within a pre-specified range. 10 random error
  added to parameterized effective radius to
  account for real data scatter.
• Use UW/Texas AM lookup table for cloud
  radiative properties
• Spectral transmittance and reflectance for ice
  and liquid clouds interpolated from
  multi- dimensional look-up table based on DISORT
  multiple scattering calculations for the
  (wavenumber range 500 2500 cm-1, zenith angle
  0 80 deg., Deff (Ice 10 157 um, Liquid 2
  100 um), OD(vis) (Ice 0.04 - 100, Liquid 0.06
  150)
• Compute EOFs and Regressions from cloudy
  radiance data base
• Regress cloud properties (i.e., p, ?, re) and
  profile against Radiance EOFs
• For small optical depth, output entire profile
• For large optical depth, output profile above
  the cloud level
• Heymsfield, A. J., S. Matrosov, and B. A. Baum
  Ice water path-optical depth relationships for
  cirrus and precipitating cloud layers. J. Appl.
  Meteor. October 2003

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MHX
MHX
December 5, 2003
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Conclusions

• The GIFTS hyperspectral measurement concept for
  observing temperature, water vapor flux, and wind
  profiles has a solid theoretical and airborne
  validated foundation.
• Clouds should not severely limit the utility of
  the GIFTS measurement concept
• The next generation operational GOES-R sounding
  system is benefiting from the scientific research
  and technology development conducted under the
  GIFTS program
• Although the completion of a space qualified
  GIFTS instrument for space validation of the
  GIFTS measurement concept awaits funding from a
  space flight geostationary satellite mission
  opportunity, the research and development will
  continue in support of the worlds next
  generation global observing system.