Craig Donlon and Ian Robinson, ESA AO9081

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• Craig Donlon and Ian Robinson, ESA AO9081
• First presented at the ENVISAT validation
  Workshop, ESA/ESRIN, Italy, December, 2002.

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Outline

• Review of validation activities
• Presentation of results
• Particular concerns
• Future validation work into 2003 and beyond
• Summary

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Validation Activities

• Based on UoL project RP16 060 AATSR Validation
  Program Work package VAL600 (Issue 4,
  14/9/01)Key activities are
• Negotiate the deployment of in situ instruments
  with shipping companies.
• Prepare and deploy ISAR radiometers during the
  post-AATSR SODAP commissioning phase of Envisat.
• Collect, process and archive in situ measurements
  measurements.
• Order and analyse AATSR data.
• Analyse in situ/satellite SSST co-locations.
• Submit processed data to the NILU database.
• Provide validation reports to the VS.

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Project Structure
PIs C. Donlon (9081) I. Robinson (9082)
CoPIs M. Reynolds (BNL) T Nightingale (RAL)
Project Manager G. Fisher
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In situ data collection

• Data/instrumentation
• ISAR radiometer SSTskin
• SSTdepth sensors SSTdepth
• UK Met Office Ship reports for each ship
• 2 operational activities in the Bay of
  Biscay/E. Channel area
• M/V Val de Loire
• May 15th - June 26th 2002
• M/V Pride of Bilbao and EU FerryBox project
• August 16th 2002 - Present

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ISAR radiometer

• An autonomous in situ IR radiometer
• Accuracy Specification /-0.1K rms
• Longevity 3 months at sea unattended
• Uses a sensitive rain gauge
• Triggers a shutter that seals the system
• Dedicated real time data log system

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ISAR Installation Val de Loire
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Other Instruments and Data

• ISAR-5C also provides
• Position
• cmg smg
• Roll/pitch/heave
• Precipitation (research)
• Master (gps) date/time

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ISAR installation Pride of Bilbao
New ISAR mount bracket New Cable run (50m !!) New
Rain Gauge mount bracket
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SOC FerryBox Experiment

• Real-time underway data via Satellite link from
• Thermosalinograph and Flourimeter
• ISAR will be interfaced to the system in January
  2003

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AATSR/ATSR-2 Validation indicator

• Derived using ISAR sky Brightness Temperatures
  (BTsky)
• Good clear sky (BTsky lt200 K)
• Fair broken cloud (200 K lt BTsky lt 260 K)
• No chance Cloudy sky (BTsky gt 260 K)
• local overpass time periods of 09301130 and
  2130-2330.
• To assess the effort/success
• EffortIndexN.Val.chances/N.days.Obs

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Val de Loire Operations
Summary of Potential validation data points
Good 37 (Effort index1.028) Fair 42
(Effort Index1.16) None 29 (Effort
Index0.806)
May 15th - June 26th 2002
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Pride of Bilbao Operations
22-26 October 2002

• No chance Cloudy sky (BTsky gt 260 K)
• Effort IndexNaN

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AATSR/ATSR-2 RA-2 data

• Started to receive data 4 weeks ago
• No time to process the data yet
• No data prior to September 2002
• Work in progress

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Particular concerns

• Piloting a new system that will mature as we
  continue through 2003
• Validation is not a 6 month only experiment
• test instrument performance
• atmospheric correction strategies
• geophysical data accuracy
• It is an important (but often overlooked)
  satellite mission component an incomplete
  validation program
• it becomes impossible to demonstrate any
  independent confidence limits for the geophysical
  satellite data products.
• In the case of satellite SST data sets having
  accuracies better than 0.3 K the quality of the
  in situ measurement becomes a critical factor
• NILU...
• Need an on-going funded validation program for
  AATSR
• Staff shortage
• Operations and equipment calibration/maintenance
  funding

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The Future

• Will continue operations on the M/V Pride of
  Bilbao until funding runs out (mid 2003).
• Collaboration with University of Miami under the
  NOPP
• ISAR aboard the Falstaff
• Inter-comparisons with other radiometers
• More ISAR radiometers are being solicited (UK,
  India, Japan, USA)
• Commercialization in July 2003
• Planned Experiment in June 2003 Aqua-Alta Tower
  N. Adriatic.
• Scatterometers
• Visible radiometers
• IR radiometers
• Effect of sea state on sky corrections