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Henk Klein Baltink Atmospheric Research Section. BBC2 radar data 24-05-2003. Outline. intercomparison 3 radars on 2003-05-24, BBC2 intercomparison 3 radars on 2001-08-03, BBC1 some issues 35 GHz cloudradar: power loss operational modes cloud mask. 24th May 2003. 3 RADARS: MIRACLE
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Henk Klein Baltink Atmospheric Research Section BBC2 radar data 24-05-2003
Outline • intercomparison 3 radars on 2003-05-24, BBC2 • intercomparison 3 radars on 2001-08-03, BBC1 • some issues 35 GHz cloudradar: • power loss • operational modes • cloud mask CloudNET Workshop Toulouse
24th May 2003 3 RADARS: MIRACLE (30 m range gate, 5 sec. average profile, ~20 dB offset) TARA (30 m range gate, 5 sec average profile) KNMI RADAR (90 m range gate, 15 sec combined profile) period: 7:40 - 9:50 UTC CloudNET Workshop Toulouse
loss of signal due to raindrops on antenna(?) artefact of mode merging melting layer precip insects rain at surface ice clouds (mixed?) 35 GHz Cloudradar data water clouds CloudNET Workshop Toulouse
24th May 2003 7:40 – 9:50 UTC 35 GHz MIRACLE TARA CT75 CloudNET Workshop Toulouse
Profiles @ 7:50 and 8:15 • reflectivity • velocity • spectral width CloudNET Workshop Toulouse
Reflectivity VerticalVelocity Ice cloud2001-8-3 BBC1 CloudNET Workshop Toulouse
research issues: • calibration of radars (BBC2/COST720) • velocity offset 35 GHz? • differences in coded / uncoded mode (dBZ, width)? CloudNET Workshop Toulouse
35 GHz radar issues • power loss • operational modes • cloud mask CloudNET Workshop Toulouse
power loss CloudNET Workshop Toulouse
After BBC1 BBC1 10000 5000 0 20 s 16 s modes 35 GHz (acquisition cycle) acquisition processing Height uncoded coded coded X-pol CloudNET Workshop Toulouse
cloud mask • based on Clothiaux et al. 1995 (5x5 pixels) • too many small clouds are masked CloudNET Workshop Toulouse
to do next months: • analyse BBC1 and BBC2 data • (analysis other datasets with multiple radar?) • improve: • mode merging • cloud mask • insect removal CloudNET Workshop Toulouse