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GEOPHYSICAL TURBULENCE

GEOPHYSICAL TURBULENCE . Geophysics − The physics of the earth and its environment, that is, earth, air, and (by extension) space. Scientific and observational needs. PHILOSOPHICAL CONSIDERATIONS.

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GEOPHYSICAL TURBULENCE

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  1. GEOPHYSICAL TURBULENCE Geophysics − The physics of the earth and its environment, that is, earth, air, and (by extension) space. Scientific and observational needs Lenschow - ATD retreat - 23 Jan 04

  2. PHILOSOPHICAL CONSIDERATIONS • Close collaboration is essential between numerical modelers, laboratory simulators and observers. • Progress in one area depends on progress in the others. Lenschow - ATD retreat - 23 Jan 04

  3. SCIENTIFIC PROBLEMS • Improve sub-filter scale parameterizations in large-eddy simulation models • Investigate complex flow regimes • heterogeneous terrain • stable planetary boundary layer • turbulent layers in stably-stratified regions from the PBL to the stratosphere • “wall” flow regimes • Study structures in turbulent flow • vortices • microfronts • rolls and cells Lenschow - ATD retreat - 23 Jan 04

  4. Shallow Drainage Flows – Mahrt, Vickers, Nakamura, Soler, Sun, Burns, & Lenschow – BLM, 101, 2001. Schematic cross-section of prevailing southerly synoptic flow, northerly surface flow down The gully, and easterly flow likely drainage flow from Flint Hills. Numbers identify the Sonic anemometers on the E-W transect. E is to the right and N into the paper. Lenschow - ATD retreat - 23 Jan 04

  5. Two RHI lidar scans from HRDL in CASES-99 illustrating the time de- pendence of waves. (a) at 05:30:49 UTC; (b) at 05:34:24 UTC. Note that the vertical scale is 7.5 times the hori- Zontal scale. Lidar Resolution 30 m. (From Blumen et al., Dynamics of Atmospheres and Oceans, 2001, Fig. 4, p. 197). Lenschow - ATD retreat - 23 Jan 04

  6. Lenschow - ATD retreat - 23 Jan 04

  7. NEW TECHNOLOGY REQUIREMENTS • Better spatial and temporal resolution for both in situ and remote (e.g. lidar and radar) measurements, including both scalars and velocity components • Greater coverage of observational domain (i.e. larger ratio of largest resolved scale to smallest resolved scale) and better integration of measurements from instrument arrays (e.g. Intelligent Sensor Array) • More accurate measurements of flow structures - from smallest scales (e.g. surface-layer eddies of 10’s of cms) to largest scales (e.g. pockets of cells, or lines of rolls of 10’s of kms) Lenschow - ATD retreat - 23 Jan 04

  8. POSSIBLE SENSOR DEVELOPMENTS • Ground-based in situ sensors • IR humidity • Tsinober turbulence probe • Larger instrument arrays for • hetereogeneous terrain studies • subfilter-scale parameterization studies • Faster, smaller, cheaper (and more robust) sensors • Laser Doppler anemometer (smaller scale & higher resolution?) • …………. Lenschow - ATD retreat - 23 Jan 04

  9. Tsinober Probe Measures , 3 components of , 9 components of and , and , 3 components of Lenschow - ATD retreat - 23 Jan 04

  10. zs = 6.90m, dys = 6.70m zd = 3.45m, dyd = 3.35m ARRAY-1 Lenschow - ATD retreat - 23 Jan 04

  11. ARRAY-4 zs = 5.15m dys = 0.63m zd = 4.15m dyd = 0.50m Lenschow - ATD retreat - 23 Jan 04

  12. IMPORTANT SCIENCE ISSUES • Reconstructing atmospheric data from laboratory templates • Comparing remote (e.g. lidar or radar) measurements with in situ measurements (e.g. velocity or trace constituents) • …... • …... Lenschow - ATD retreat - 23 Jan 04

  13. Lenschow - ATD retreat - 23 Jan 04

  14. POSSIBLE SENSOR DEVELOPMENTS • Remote • trace constituent and air velocity lidars with fine-scale resolution for ground and mobile platforms • millimeter Doppler radar • portable VHF wind profiler • ….. • ….. Lenschow - ATD retreat - 23 Jan 04

  15. POSSIBLE SENSOR DEVELOPMENTS • Aircraft • fine-scale temperature in cloud • fine-scale humidity measurement • fine-scale trace constituent measurement • laser velocity measurement (3-D) • velocity difference measurements (via pressure differences) • fine-scale ocean waves via lidar or radar • ….. • ….. Lenschow - ATD retreat - 23 Jan 04

  16. NEW PLATFORMS • Unmanned Aerial Vehicles (UAV) • TRAnsect Measurement (TRAM) • Balloon- and kite-borne sensor packages • ….. • ….. Lenschow - ATD retreat - 23 Jan 04

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