1. BALTEX BRIDGE Cloud Campaign part 2

2. Guide What is BBC2? Why BBC2? Instrumentation Organisation

3. What is BBC2? Large international measurement campaign 100 researchers, 20 institutes, 5 countries Additional instrumentation in Cabauw Tethered balloons Aircraft Lead by KNMI Natural follow-up of BBC (Augustus-September 2001) April - May 2003 Topics: Cloud, aerosols, radiation and there interactions

4. Why BBC2? Improve the estimates of change of climate based on climate model runs: 1.4 – 5.8K temperature

5. Why BBC2? uncertainties can largely be attributed to shortcomings in the representation of cloud related processes in GCMs International Panel on Climate Change: improve the representation of clouds in climate models increase knowledge of cloud related processes need for dedicated highly accurate measurements of cloud properties

7. Clouds and climate change Low level clouds cool the earth High level clouds warm the earth Future cloud climatology increase low level clouds = negative feedback increase high level clouds = positive feedback

8. Clouds and climate models Cloud cover fraction

9. Clouds and climate models Liquid water path Water path

10. BBC2 main topics Radiative transport in inhomogeneous cloud fields Improvement measurement techniques Synergy: Lidars, radars, microwave radiometers,.. Satellite retrievals (MSG, AVHRR, SCIAMACHY) Improvement of cloud representation in models Focus on boundary layer clouds Radiation and aerosols

11. Radiative transport in inhomogeneous cloud fields Inhomogenous clouds Model: plane parallel homogeneous clouds Different Photon Paths: Absorption, angular distribution

12. Radiative transport in inhomogeneous cloud fields Inhomogenous clouds Model: plane parallel homogeneous clouds Different Photon Paths: Absorption, angular distribution

13. GCM’s Transmissivity versus Cloud Cover, Cabauw Radiative transport in inhomogeneous cloud fields

14. Improvement of measurement techniques Ground based instruments - Oxygen A band spectrometer

15. Improvement of measurement techniques Ground based instruments - synergetic methods

16. MSG retrieval validation Framework CM SAF cloud top temperature, phase, liquid water, optical properties

17. Improvement of measurement techniques Satellite based instruments

18. adiabat Data provided by: S. Rodts, Delft University, thesis available from:http://www.phys.uu.nl/~www.imau/ShalCumDyn/Rodts.html Improving cloud representation in models Understanding entrainment in boundary layer clouds (SCMS Florida 1995)

19. Verification (with LES) Cloud cover

20. Verification (with Observations)

21. Aerosols and radiation Plaatje Wouter

22. BBC2 - Participants Royal Netherlands Meteorological Institute, KNMI Meteorological Institute University of Utrecht, IMAU CESAR partners: RIVM, TUD, ECN, TNO/FEL, WU, ESA, TUE 4D-wolken partners GKSS, Uni. Bonn, Berlin, Leipzig, Heidelberg, Kiel Aicraft consortium MeteoFrance, UK MetOffice, FU Berlin, Uni. Leipzig INTA (Spanish) Additional Centre d’électronique de l’armement LOA (Uni Lille), Uni Leeds,..

23. Cabauw - CESAR Cabauw Experimental Site for Atmospheric Research Radars 1.2 GHz radar (KNMI) 3 GHz radar (TUD) 35 GHz radar (KNMI) Lidars Lidar (RIVM) Lidar ceilometer (KNMI) CIMEL (TNO/FEL) Microwave 22 channel microwave radiometer (Uni. Bonn) 20,30,50 GHz microwave rad. (TUE) Sodar/RASS (KNMI) GPS receiver (TUD) Rain gauges (WU) Scintillometer (WU) Instrumentation for land/atmosphere interaction studies

24. BBC2-Cabauw-extra Radars 94 GHz cloud radar MIRACLE (GKSS) 24 GHz Micro rain radars (WU, 2x Uni. Bonn) Lidars Raman-lidar, ARAS (GKSS) Microwave MICCY (Uni. Bonn) 20, 30, 50GHZ radiometer (ESA/ESTEC) 13GHZ Radiometer (ESA/ESTEC) Commercial microwave radiometer (RPG) Sodar/RASS Ift Leipzig Camera Infra-red cameras (France) Tethered balloons: IMAU, Leipzig (microphysics) Radiosondes: 4 per day, Army (land forces)

25. BBC2-Cabauw-extra Radiation components: Fluxes (BSRN upgrade, KNMI) Oxygen-A band spectrometers (Uni. Heidelberg) Albedometer (IfT Leipzig) Sunphotometer (IfT Leipzig) SunPhotometer CIMEL (TNO/FEL) Narrow beam spectrometer (FUB) UV Spectrometer (RIVM)

26. MAPSY Balloon Uni. Leipzig Length: 21.2 m; Diameter: 6.54m; Volume: 450m 3 Max. Height: 1500m; Max. Payload: 150kg Instruments Meteorological parameters Wind vector at 300Hz PVM (LWC, Reff) Fast FSSP (n(r)) Condensation Particle Counter

27. BBC2-Aircraft Merlin (Meteo France) Partenavia (IfT Leipzig) CASA (INTA) Dornier (UK MetOffice)

28. BBC2-Aircraft: Merlin IV (Meteo France) Cloud  -physics (GKSS) Fast FSSP FSSP 100, extended range 2D-C 2D-P Nevzorow probe PVM King probe CCN counter (optional) Fast w,q,T DIRAM (IMAU) Various other radiation

29. BBC2-Aircraft: Partenavia (IfT Leipzig) Meteorological parameters Microphysics Optical particle counter (Aerosol size) PVM (LWC and Reff) Nevzorov (LWP, TWC) Radiation components Spectral resolved fluxs up-down (0.3 – 1 micron) Spectral resolved actinic fluxes

30. BBC2-Aircraft: CASA (INTA) Radiation (FUB) - FUBISS (spectrograph) - MIDAC (FTIR) - Casi (imaging spectrograph) IR imagers (INTA) Airborn version of POLDER MiniMIR (polarization at 0.6 and 1.6micron)

31. BBC2 - Flight tracks Type 1: Water clouds over land Cabauw - parallel to the wind Aircraft under, in and on top of cloud layer No-precipitation, no cirrus, satellite overpass. Type 2: Cloud free conditions Surface characteristics (thermal and optical) Aerosol

32. BBC2 - Flight tracks 

33. BBC2 – Flight plan 3 aircraft flying in concert

35. BBC2 – Organisation In the early morning cloud forecast When, where, why? Wind direction and speed, cloud altitude Precipitation? cirrus? Cloud top below freezing level? Flight Planning Meteorologist Internet + MWS Consultation of aviation meteorologist Rotterdam Update (model runs, observations (Cabauw)) Decision Air Trafic Control (Amsterdam) / KLU (Nieuw Millingen) In flight changes

36. BBC2 – Organisation Local Organising Committee Arnout Feijt Irene Das Pier Siebesma Wim Hovius Henk Klein Baltink Wouter Knap Contributors FPMs, WA, WM, Uni. Bonn,..

37. BBC2 summary Large international campaign clouds, radiation, aerosols April - May 2003 Fits IPCC recommendations Well embedded in aims Atmos. Res. Dept. CESAR www.knmi.nl/samenw/bbc2/ Open to suggestions for extention

38. BBC2 additional topics Rain Micro and macrostructure Cirrus clouds SCIAMACHY validation Orientation Turbulent structure of the convective boundary layer

39. BBC2 SCIAMACHY validation

41. BBC2 GOME validation

42. BBC2 Turbulent structure of the convective boundary layer Goals - Understand the atmospheric budgets of wind, temperature, humidity and carbon dioxide. Assess the added value of turbulence characteristics derived from ground based remote sensing sensors, i.e. windprofiler for clear sky part and cloud radar for boundary layer clouds. How - Observe the profiles of fluxes in the convective boundary layer with a suite of ground based en tower based in-situ observations, remote sensing observation, ballon observations and airplane observations. - Use detailed boundary layer models for interpretation of the observations.