Delft University of Technology 1 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar? A.C.P. Oude Nijhuis, C.M.H. Unal, O.A. Krasnov, H.W.J. Russchenberg and A. Yarovoy

Delft University of Technology 2 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Introduction & Motivation

Delft University of Technology 3 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 We all want a safe flight... EXCLUSIVE: 'WAKE TURBULENCE' & PILOT ERROR COULD HAVE CAUSED SFO ASIANA CRASH (7 Jul 2013)

Delft University of Technology 4 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 We all want a safe flight...

Delft University of Technology 5 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Air planes can crash because of a WV when: * They hit a wake vortex * They experience a roll moment * They are close to the ground * They have little time to correct

Delft University of Technology 6 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Solution to increase capacity??? * Montoring WVs

Delft University of Technology 7 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Solution - New radars and lidars have higher sensitivities. - They can scan the glide slope and detect the WVs and weather hazards.

Delft University of Technology 8 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Solution WVs and weather hazards can be monitored under all weather conditions by using scanning radars and lidars! ???????!!!!??????? Solution to mitigate weather hazards and increase airport capacity:

Delft University of Technology 9 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 WV monitoring along the glide slope Mode-S Downlink Radar/Lidar Sensors

Delft University of Technology 10 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 We would like to improve turbulence retrievals and improve wake vortex monitoring. How to do this? WV and turbulence monitoring Imrpove turbulence retrievals Improve WV monitoring Improve wind retrievals Improve WV detection and retrievals Measurement analysis:  Use CESAR. Simulations

Delft University of Technology 11 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 We would like to improve turbulence retrievals and improve wake vortex monitoring. How to do this? Use the Cabauw research site and apply EDR retrievals to the available radars. Try to answer the question how radars and lidars can be used to retrieve turbulence. Make a validation with other instruments to conclude whether the results are reliable. WV and turbulence monitoring

Delft University of Technology 12 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Do eddy dissipation rate retrievals work for preciptation profiling Doppler radar? methods

Delft University of Technology 13 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Cabauw research site TARA (S-band RADAR) measures the vertical Doppler verlocities at Cabauw. 330 m Tower with sonic anemometer at 180 m. (and other levels) Atmospheric Profiling between 180 m and ~ 15 km.

Delft University of Technology 14 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Methods The eddy dissipation rate (EDR) is based on the assumption of homogenous isotropic frozen turbulence. In the inertial sub-range the dissipation goes with a -5/3 power. Figure from O'Connor (2010).

Delft University of Technology 15 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Methods Several retrieval methods are possible: Use the Doppler spectral width. Use a sequence of Doppler velocities. Several methods exist for analysis: 1. variance, 2. power spectrum, 3. structure functions. The eddy dissipation rate (EDR) is based on the assumption of homogenous isotropic frozen turbulence. In the inertial sub-range the dissipation goes with a -5/3 power.

Delft University of Technology 16 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Do eddy dissipation rate retrievals work for preciptation profiling Doppler radar? Results

Delft University of Technology 17 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Application to sonic anemometers Measurements from the sonic anemometers on June 21st Hz vertical speeds are converted into EDR values with different methods. Time domain is used, and average horizontal wind speed is used. 10 minutes of data are used.

Delft University of Technology 18 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Application to TARA Measurements from the TARA on June 21st Vertical speeds (terminal fall speed subtracted) are converted into EDR values with different methods. Time domain is used, and average horizontal wind speed is used. 10 minutes of data are used.

Delft University of Technology 19 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Application to TARA Measurements from the TARA on June 21st Doppler spectral width are converted into EDR values. Eq. Refl. is used to estimate the drop size distribution.

Delft University of Technology 20 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Problem! One storm event is not giving any conclusive analysis… … solution: use one year of TARA and CESAR data for analysis.

Delft University of Technology 21 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Solution Apply edr retrievals to one year of TARA data and sonic anemometer data. Make scatter density plots of all variables against all variables to understand what is gonig on. Parameters BSRN site (radiation parameters) IDRA reflectivity Nubiscope cloud cover Sonic wind speed, wind direction, EDR TARA reflectivity, wind speed, wind direction, EDR Tower temperature, humidity, etc.

Delft University of Technology 22 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 First results Different EDR methods applied to the sonic anemometer look ok. Different EDR methods applied to TARA look ok. Comparison of wind direction between TARA and sonic goes well. Comparison of EDR form TARA against sonic anemometer does not go well. Variance in differential reflectivity can be an interesting parameter for the estimation of EDR.

Delft University of Technology 23 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Outlook Check for bugs and/or errors. Use angular statistics for comparison of direction. Use 10 min. average for comparison of wind speed and wind direction. Do the analysis for different rain intensities Simulations for better understanding Develope advanced algorithms

Delft University of Technology 24 Do eddy dissipation rate retrievals work for precipitation profiling Doppler radar?, CESAR Science Day, June 18th, 2014 Outlook fall speed Spectral fall speed width