Dias nummer 1

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Operational use of ENVISAT at the Danish
Meteorological Institute Preliminary Results and
Experience from the first two months Keld Q.
Hansen DMI

International Ice Charting Working Group V
Hamburg 19-23 April 2004
2
Why use ENVISAT?
International Ice Charting Working Group V
Hamburg 19-23 April 2004
3
HISTORY Main Operation area Cape Farewell (all
offshore inshore routes)

• February 1999
• Aircraft and helicopter as primary data source
• satellite data used complementary
• Test of operational use of SAR data

International Ice Charting Working Group V
Hamburg 19-23 April 2004
4

• March 1999 ?
• Radarsat primary data source for ice mapping
  (offshore)
• Helicopter used inshore
• June-July (surface melt water) ice recco
  aircraft in service in combination with Radarsat

International Ice Charting Working Group V
Hamburg 19-23 April 2004
5

• The launch of ENVISAT (March 2002) was expected
  to realize this future opportunity.. but time
  went by .
• Summer 2003 first ice season without ice recco
  aircraft BUT only ONE satellite luckily the ice
  season was the lightest in 50 years

• Winter 2003/04 contract with Kongsberg Satellite
  Station on delivery of 250 Envisat scenes/year (
  data from Tromsø and Gatineau).
• The operational setup is complicated by the fact
  that we need direct broadcast and taped data to
  cover all areas of interest.
• Only limited evidence of ENVISATs operational
  capability.
• We decided to only use ENVISAT outside DMI
  primary mapping area

International Ice Charting Working Group V
Hamburg 19-23 April 2004
6

• Planning of SAR scenes
• ENVISAT DESCW (developed by ESA)
• designed for multi purposes
• inflexible (shifting scenes is difficult)
• not user friendly (100s of mouse clicks)
• time consuming
• RADARSAT SPA (Swath Planning Application)
• single purpose
• simple
• flexible
• saves swathplans in various formats at the same
  time

International Ice Charting Working Group V
Hamburg 19-23 April 2004
7
Statistics for SAR data received at
DMI RADARSAT Feb04 Mar04 Apr04 Planned 45
34 18 Received NRT 44 34 15 ENVISAT Feb04
Mar04 Apr04 Planned 5 14 14 Received NRT 4
6 8 Status April 16
International Ice Charting Working Group V
Hamburg 19-23 April 2004
8

• Experienced ENVISAT NRT Problems
• Scene is cancelled
• example 15th April 2004
• Order cancelled by ESA due to conflict.
• (message received 2 hours after satellite
  pass)
• Scene is delayed
• Scene does not cover 500 km
• Scene is shifted north-south

International Ice Charting Working Group V
Hamburg 19-23 April 2004
9
ENVISAT Processing at DMI Image contrast /
brightness have to be improved, 16 bits ? 8 bits
ENVISAT ASAR 12 April 2004 0028 UTC
RADARSAT SCANSAR Wide 11 April 2004 2038 UTC
International Ice Charting Working Group V
Hamburg 19-23 April 2004
10

• Status Mid-April 2004
• Radarsat is still the primary data source in the
  Cape Farewell area.
• Envisat complementary.
• May 2004 Test of Envisat operational capability
  outside Cape Farewell area ? No Radarsat data
  ordered !!!!

International Ice Charting Working Group V
Hamburg 19-23 April 2004
11

• Future
• We expect stable delivery of data to be
  accomplished we need more than 95 success
  rate.
• We would like to reduce time from order to
  actual satellite pass, do anybody have experience
  with emergency planning ?
• We need to improve image contrast / brightness
  (DMI, ESA ?)
• Continuous dialogue on faster and stable NRT
  delivery with the purpose of improving the
  service (KSAT, ESA)
• We look forward to user friendly swath planning
  software (ESA)
• Aircraft backup back up in 2004
• RADARSAT is an excellent backup for ENVISAT
• ENVISAT has until now NOT proved backup potential

International Ice Charting Working Group V
Hamburg 19-23 April 2004
12
ESA.?
International Ice Charting Working Group V
Hamburg 19-23 April 2004