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1 Joe Werne Colorado Research Associates Division NorthWest Research Associates, Inc. 3380 Mitchell Lane Boulder, CO 80301 werne@cora.nwra.com 303-415-9701 x 207 26 September 2005 Validation Information for DNS Solutions
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= Experiment = Simulation Universal Symbols
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Wind shear: Balloon Comparison Chen, Kelley, Gibson-Wilde, Werne & Beland, Annales Geophysicae, 2001
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Coulman, Vernin, Fuchs Wind shear: Balloon Comparison CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995)
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Mixing Layers through the Troposphere and Stratosphere CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995)
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Ierkic, Woodman & Perillat, Radio Science 25, 941 (1990) Radar Backscatter Re ~ 10 6 -10 7 120 m
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U.S. Air Force anemometry data also, Michael Roggeman, private communication, 2001 Bruce Masson, 1996
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Fort Collins Photo Colorado Springs, Colorado, 2000 (photo by Tye Parzybok)
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Denver Photo Denver, Colorado, 1953 (photo by Paul E. Branstine)
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Estes Park, 1979 Estes Park, Colorado, 1979 (photo by Bob Perney)
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Joe’s Back Yard Lafayette, Colorado, 2002 (photo by Joe Werne)
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DNS computed solutions Kelvin-Helmholtz Viscous & Thermal Dissipation
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CT2 fits from DNS 2 nd -order structure-function fits Werne & Fritts, 2000 Exponent between 2/5 and 2/3 Systematic dependence in x. C T 2 = 3.3 ε -1/3 χ 0 = 7.4 K
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CU2 fits from DNS 2 nd -order structure-function fits Werne & Fritts, 2000 Exponent between 2/5 and 2/3 C U 2 = 2.1 ε 2/3 0 = 11.3 K 0 = 8.0 K We have also computed structure-function fits for V and W, but until recently data were not available. Wroblewski, Cote, Hacker, Crawford, 2002
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Comparison with Egrett 2 nd -order structure-function fits Werne & Fritts, 2000 Wroblewski, Cote, Hacker, Crawford, 2002 C V 2 /C U 2 C W 2 /C U 2 C U 2 /C T 2 C W 2 /C T 2 z, altitude (km) C U 2, C V 2, C W 2, C T 2, exponents, inner scale all consistent with measurements.
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Peak-to-midlayer ratios Kelvin-Helmholtz: Balloon Comparison Chen, Kelley, Gibson-Wilde, Werne & Beland, Annales Geophysicae, 2001
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CT2 fits, continuous in time CT2CT2 T Structure Function Fits Werne, Meyer, Bizon & Fritts, 2002 lolo time z xy
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CU2 fits, continuous in time U Structure Function Fits Werne, Meyer, Bizon & Fritts, 2002 CU2CU2 lolo time z xy
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Combine Simulation and Observation for an operational path
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CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995) Combine Simulation and Observation for an operational path
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CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995)
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CT2CT2 RiRi T Combine Simulation and Observation for an operational path
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CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995) Combine Simulation and Observation for an operational path
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CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995) Combine Simulation and Observation for an operational path
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CT2CT2 RiRi T Coulman, Vernin & Fuchs, Applied Optics 34 5461 (1995) Combine Simulation and Observation for an operational path
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Conclusions 1. Stratification restricts mixing dynamics to vertically confined regions. 2. Entrainment zones maintain sharp thermal gradients that dominate optical effects. 3. Mixing in the interior of turbulent layers reduces thermal gradients. 4. Mixing zones in wind-shear simulations duplicate morphology exhibited by cloud observations. 5. Potential-temperature profiles, duration, C T 2 profiles, and Ri profiles agree with balloon measurements. 6. Turbulence constants C θ and C (relating χ and Є to C T 2 and C U 2 ) and C V 2 /C U 2 and C W 2 /C U 2 obtained from comparison with the middle of a simulated shear layer agree with atmospheric measurements, as do the spectral slope and inner scale. 7. Entrainment zones are non-stationary, inhomogeneous, and anisotropic; unfortunately they also have the greatest impact on optical propagation. 8. Dynamic SGS is promising for stable stratification, but systematic dependence on filter width limits generality of method. 9. Improved modeling is required for further progress with LES. This is in progress.
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