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Ions and Highly Charged Particles in the Atmosphere

Ions and Highly Charged Particles in the Atmosphere. Thomas Leisner, Technische Universiät Ilmenau, Germany. - The global electrical circuit. - The Role of Charges in the Climate System. - Laboratory Experiments on Charged Levitated Droplets. - The Stability of Highly Charged Droplets.

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Ions and Highly Charged Particles in the Atmosphere

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  1. Ions and Highly Charged Particles in the Atmosphere Thomas Leisner, Technische Universiät Ilmenau, Germany - The global electrical circuit - The Role of Charges in the Climate System - Laboratory Experiments on Charged Levitated Droplets - The Stability of Highly Charged Droplets www.physik.tu-ilmenau.de/exp2/home.htm

  2. Anthropogenic climate change ? www.physik.tu-ilmenau.de/exp2/home.htm

  3. The 11 year sunspot cycle www.physik.tu-ilmenau.de/exp2/home.htm

  4. Correlation between cosmic rays and cloud coverage symbols : cloud coverage solid line: cosmic rays adapted from H. Svensmark, Phys. Rev. Lett. 81, 5027, (1998) www.physik.tu-ilmenau.de/exp2/home.htm

  5. Simplified global electrical circuit E~100V/m www.physik.tu-ilmenau.de/exp2/home.htm

  6. A connection between solar wind activity and climate? solar wind activity magnetosph. particles cosmic rays space weather and atmospheric electricity atmospheric current density cloud space charge observed correlations cloud microphysics highly charged evaporation residues (good ice nulei) electroscavenging enhances ice formation radiation transport and cloud albedo precipitation and latent heat release atmosphericphysics atmospheric temperature and dynamics www.physik.tu-ilmenau.de/exp2/home.htm

  7. Cloud microphysics in the laboratory feedback control W CCDarray www.physik.tu-ilmenau.de/exp2/home.htm

  8. Experimental www.physik.tu-ilmenau.de/exp2/home.htm

  9. Climate chamber and levitator periphery www.physik.tu-ilmenau.de/exp2/home.htm

  10. Connection to the Raman microscope (Yobin Yvon) www.physik.tu-ilmenau.de/exp2/home.htm

  11. Connection to the Bruker IFS 66 FTIR with IRscope II www.physik.tu-ilmenau.de/exp2/home.htm

  12. Determination of size and index of refraction r= 19.973 µm, n=1.4087 www.physik.tu-ilmenau.de/exp2/home.htm

  13. Freezing phase transitions in droplets www.physik.tu-ilmenau.de/exp2/home.htm

  14. Determination of the nucleation rate www.physik.tu-ilmenau.de/exp2/home.htm

  15. Homogeneous nucleation rates of water Journal of Chemical Physics, 111, 6521, (1999) Journal of Molecular Liquids 96-97, 153(2002) www.physik.tu-ilmenau.de/exp2/home.htm

  16. Dynamics of highly charged droplets + + + + + + 100 kV/m - ~100 V/m 10 kV/m - - - thunderstorms are the generators of free charges in the atmosphere most of the mechanisms for charge separation include collisionsbetween droplets or ice crystals www.physik.tu-ilmenau.de/exp2/home.htm

  17. A mechanism of charge separation in thunderstorm clouds Supercooled cloud droplet nucleation starts on surface Theromodiffusion leads to charge separation Outer shell splinters carry postitive charge upward www.physik.tu-ilmenau.de/exp2/home.htm

  18. Is homogeneous freezing of water a surface or bulk process? www.physik.tu-ilmenau.de/exp2/home.htm

  19. Stability of highly charged droplets The quadrupole oscillation (l=2) is unstable if the fissillity: stability is determined by interplaybetween surface energy and coulombenergy. Lord Rayleigh 1882: the frequency of mode l is given by: Though a quadrupole deformation would ultimately lead to symmetric fission, LordRayleigh did predict an asymmetric disintegration of the droplet: If ... (X>>1)... the liquid is thrown out in fine jets, whose fineness however has a limit" Philosophical Magazine, XIV, 184, (1882) (Rayleigh did not mention the X=1 case) www.physik.tu-ilmenau.de/exp2/home.htm

  20. Coulomb- instability of an evaporating droplet www.physik.tu-ilmenau.de/exp2/home.htm

  21. Fast microscopy of the disintegration process Photo-multiplier cw laser beam Trigger and delay unit Long working distance microscope CCDcamera Fast flashlamp injector phase function measurement Image processor www.physik.tu-ilmenau.de/exp2/home.htm

  22. Rayleigh jets www.physik.tu-ilmenau.de/exp2/home.htm Nature, Jan. 9, 2003

  23. 100µm Fast microscopy of the disintegration process t=0 t=130µs t=135µs t=140µs t=145µs t=150µs t=152µs t=153µs t=154 µs t=155 µs t=158 µs t=160µs t=165µs t=170µs t=180µs t=200µs

  24. Droplet geometry during instability 4.0 180 3.5 160 3.0 140 / degree 120 2.5 100 aspect ratio 2.0 80 tip angle 1.5 60 1.0 40 jet visible 0.5 20 0.0 0 140 160 180 200 220 time (µs) www.physik.tu-ilmenau.de/exp2/home.htm

  25. Summary of Observations • initially the droplets deform ellipsoidally (X=1, l=2 is unstable) • when an aspect ratio of 3.5 is reached, two sharp tips are formed at the poles • when the tip angle drops below 60° a fine jet is emitted from each tip • the jet is emitted within 5µs, with speed up to 50m/s • each jet disintegrates into roughly 50 small daughter droplets, 1.5 µm in diameter • in one event the total charge loss is 30%, mass loss about 0.3% • the dynamics is remarkably independent of size and surface tension www.physik.tu-ilmenau.de/exp2/home.htm

  26. Acknowledgement TU Ilmenau Klaus Hemmelmann Andreas Richter Denis Duft Rene Müller Tobias Achtzehn Collaboration: Claude Guet, CEA Paris Bernd Huber,CEA Caen Ilmenau www.physik.tu-ilmenau.de/exp2/home.htm

  27. Simulation of the jet breakup v0= 5m/s v0= 50m/s www.physik.tu-ilmenau.de/exp2/home.htm

  28. Light scattering from an oscillating droplet: Laser www.physik.tu-ilmenau.de/exp2/home.htm Phys. Rev. Lett., (accepted)

  29. www.physik.tu-ilmenau.de/exp2/home.htm

  30. Correlation between solar wind activity and cosmic rays adapted from H. Svensmark, Phys. Rev. Lett. 81, 5027, (1998) www.physik.tu-ilmenau.de/exp2/home.htm

  31. www.physik.tu-ilmenau.de/exp2/home.htm

  32. Terrestrial Effects of Space Weather Aurorae Geomagnetical storms effect communication and navigation Satellite damage Radiation hazards to flight personnel Climate effects? www.physik.tu-ilmenau.de/exp2/home.htm

  33. A connection between solar wind activity and climate? solar wind activity magnetosph. particles cosmic rays atmospheric current density cloud space charge observed correlations highly charged evaporation residues are good ice nulei electroscavenging enhances ice formation radiation transport and cloud albedo precipitation and latent heat release atmospheric temperature and dynamics adapted from B.A. Tinsley, Space Science Review 94 , 215, (2000) www.physik.tu-ilmenau.de/exp2/home.htm

  34. Light scattering from an oscillating droplet Laser www.physik.tu-ilmenau.de/exp2/home.htm Phys. Rev. Lett., (accepted)

  35. The instability occurs at X=1 ! experiment theory PRL 89, 084503, 2002 www.physik.tu-ilmenau.de/exp2/home.htm

  36. Light scattering during Coulomb instability www.physik.tu-ilmenau.de/exp2/home.htm

  37. An anayltical shape class for spindle like objects V: spindle volume: aspect ratio: relative displacement of the generating ellipse (tippedness of the shape) with: www.physik.tu-ilmenau.de/exp2/home.htm

  38. Droplet geometry during instability 4.0 180 3.5 160 3.0 140 / degree 120 2.5 100 aspect ratio 2.0 80 tip angle 1.5 60 1.0 40 jet visible 0.5 20 0.0 0 140 160 180 200 220 time (µs) www.physik.tu-ilmenau.de/exp2/home.htm

  39. Open questions • How universal is the phenomenon (temperature, size, surface tension, viscosity) ? • Is this process a relevant source of atmospheric nuclei ? • Is the ejected material from the droplet surface ? • Is it possible to induce the instability below X=1 ? www.physik.tu-ilmenau.de/exp2/home.htm

  40. Forced oscillations of incompressible viscous droplets Vibration of mode l is governded by: With the effective dynamic parameters: nach R. W. Hasse, Annals of Physics, 1975, 93, 68 www.physik.tu-ilmenau.de/exp2/home.htm

  41. Does the solar activity cycle influence the earth climate? www.physik.tu-ilmenau.de/exp2/home.htm

  42. Types of solar activity Solar Wind: Quiet particle stream Flare: Explosion on Sun surface Protuberance: Ejection of particles from the sun surface CME: Coronal mass ejection: Ejection of plasma from the corona www.physik.tu-ilmenau.de/exp2/home.htm

  43. Ions and Highly Charged Particles in the Atmosphere Thomas Leisner, Technische Universiät Ilmenau, Germany - The Electrical State of the Atmosphere - The Role of Charges in the Climate System - Experiments on Single Levitated Droplets - The Stability of Highly Charged Droplets www.physik.tu-ilmenau.de/exp2/home.htm

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