Colocated Validation Data

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Co-located Validation Data

• TES/HIRDLS Comparison for Reduced Resolution Mode

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The Satellites
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• High Resolution Dynamics Limb Sounder (HIRDLS)
• 21-channel limb-scanning infrared radiometer,
  which includes window channels for aerosol/cloud
  detection
• Cloud Top Height is an operational product
  (pointing error, operational HIRDLS altitudes are
  accepted to be higher by 1.7 km than intended)
• Soon extinction information to be retrieved
• Tropospheric Emission Sounder (TES)
• Infrared-imaging, limb and nadir sounding
  Fourier Transform Spectrometer which measures
  spectra between 650 - 3050 cm-1 at a resolution
  of
• 0.02 cm-1 for altitudes between 0 33 km.
• Operationally reports Cloud Top Height,
  frequency-dependent Cloud Optical Depth and
  Average Effective Cloud Optical Thickness (nadir
  measurements)
• Ozone Monitoring Instrument (OMI)
• UV and visible hyperspectral imager
• Cloud Scattering Layer Pressure
• Microwave Limb Sounder (MLS)
• Microwave emission limb-radiometer/spectrometer
• Cirrus Ice content

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Statistical comparisons ONLY
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Cloud Frequency 2 May 2006
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Cloud Top Height 2 May 2006
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Cloud Top Height 2 May 2006
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Cloud Extinction Coefficient 2 May 2006
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Conclusions

• Qualitatively
• MIPAS retrieved cloud products of cloud top
  height and cloud extinction coefficient compare
  well with HIRDLS cloud top height and TES cloud
  top height and cloud optical depth.
• HIRDLS shows the highest cloud tops and TES the
  lowest, but taking into account the known 1.7 km
  pointing error associated with HIRDLS and the
  fact that TES cloud products are from it's
  nadir-viewing measurements, the cloud top heights
  reported by all three instruments agree quite
  well.
• MIPAS and TES report a near-global coverage of
  extinction coefficient of 10-2 km-1 but TES
  exhibits more structure globally than does MIPAS.
• All instruments show the same global
  distribution, with increased
• probability of finding cloud in the tropics and
  less at the poles. However, MIPAS notes far less
  cloud detected than do the other two instruments.