1 / 33

Lightning Climatology Oklahoma Lightning Mapping Array May - September, 2004 - 2005

Lightning Climatology Oklahoma Lightning Mapping Array May - September, 2004 - 2005. Paul Krehbiel New Mexico Tech September 28, 2005. Lightning Mapping Arrays (LMAs). Utilize time-of-arrival technique Consist of 10-12 stations over 50-70 km diameter area

gauri
Download Presentation

Lightning Climatology Oklahoma Lightning Mapping Array May - September, 2004 - 2005

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lightning Climatology Oklahoma Lightning Mapping Array May - September, 2004 - 2005 Paul Krehbiel New Mexico Tech September 28, 2005

  2. Lightning Mapping Arrays (LMAs) • Utilize time-of-arrival technique • Consist of 10-12 stations over 50-70 km diameter area • Passive system: locates impulsive radio frequency signals produced by lightning (radio 'static') • Listens in a locally unused VHF TV channel (e.g., Ch 3, 5, 8) • Produce observations in near real-time (1-2 minute delay) • Provide good spatial accuracy and temporal resolution Existing systems: • New Mexico Tech LMAs: Northern Alabama (NASA/Huntsville), Oklahoma (OU/NSSL), Langmuir Laboratory (NMT), WSMR, ... • Vaisala (formerly GAI) LDAR II: Dallas/Ft. Worth, Houston (TAMU), Kennedy Space Center.

  3. Oklahoma LMA data: • Real time observations: • Cover a large area (400-500 km diameter) • 3D over 200-300 km diameter area • Data are simultaneous; short update times (2 min) Useful information: • Plan source densities (vertically integrated) • Altitude vs. time source density plots Lightning activity shows where strong convection is occurring, and if intensifying or weakening (See lightning.nmt.edu)

  4. Zoomed-in example: Density of Points Display Moore, OK tornadic storm May 10, 2003 10 min of observations (NLDN events in green) -> xlma analysis software Texas

  5. Climatology Data from Oklahoma LMA The following slides show on a month-by-month basis the number of located LMA sources as a function of the day of the month and the hour of each day, in the form of a 3-dimensional bar graph (generated using the ‘bar3’ plotting tool of Matlab). The vertical bars indicate the number of sources per hour on a logarithmic scale to prevent large mesoscale systems from dominating the plots. The units are kilosources/hour, with a threshold value of 1000 sources/hour being applied to discriminate against weakly-detected, distant storms from cluttering up the presentation (any storm of reasonable size and within range of the LMA will produce several thousand sources/hour). To determine what the storms look like during an active period, see http://lightning.nmt.edu/oklma. (Bar graphs are shown only for April through September but are available for the entire year.)

  6. Number of located LMA sources, April 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  7. Number of located LMA sources, April 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  8. Number of located LMA sources, May 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  9. Number of located LMA sources, May 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  10. Number of located LMA sources, June 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  11. Number of located LMA sources, June 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  12. Number of located LMA sources, July 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  13. Number of located LMA sources, July 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  14. Number of located LMA sources, Aug. 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  15. Number of located LMA sources, Aug. 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  16. Number of located LMA sources, Sept. 2004, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  17. Number of located LMA sources, Sept. 2005, Oklahoma (Daylight ~12-24 UTC; 7 am – 7 pm CDT)

  18. For real-time data plots, archived daily and hourly, see http://lightning.nmt.edu/oklma

  19. Lightning Climatology STEPS 2000 Lightning Mapping Array (NW Kansas, E Colorado, SW Nebraska) May 24 – August 10, 2000

  20. Two supercell storms in NW Kansas–SW Nebraska - June 7, STEPS 2000 -13 station LMA network - Close storm: Low Precip - Far storm: High Precip - 10 min time interval - ~Continuous IC lightning - Inverted polarity storms (deep mid-level + charge) - Only one NLDN event - negative CG (real?) - Major advantage of total lightning vs. CG only Note: Major Ch 3 TV interference, data processed with auto- thresholding.

  21. Aircraft track and storms, May 25, STEPS 2000 (Aircraft being charged while flying through down- wind cirrus/anvil cloud)

  22. Example of Highly Dendritic Negative CG flash Height vs Time Height vs E-W Plan View Height vs N-S

  23. Number of located LMA sources, May 2000, STEPS (Daylight ~12-02 UTC; 6 am – 8 pm MDT)

  24. Number of located LMA sources, June 2000, STEPS (Daylight ~12-02 UTC; 6 am – 8 pm MDT)

  25. Number of located LMA sources, July 2000, STEPS (Daylight ~12-02 UTC; 6 am – 8 pm MDT)

  26. Number of located LMA sources, August 2000, STEPS (Daylight ~12-02 UTC; 6 am – 8 pm MDT)

  27. (The End)

  28. Time-of-Arrival Concept: impulsive lightning event at (x, y, z; t) z y x

  29. Oklahoma Lightning Mapping Array 11 station network, 50 km diameter Real-time processing & display University of Oklahoma/National Severe Storms Laboratory

  30. Oklahoma LMA Station

  31. North Alabama Lightning Mapping Array (NASA) Map (10 stations) http://branch.nsstc.nasa.gov/ One hour of real-time data

  32. New Mexico LMA Networks

  33. Portable LMA System (Vortex II, DC Network, DC3?) • Electronics housed in shielded thermoelectric cooler enclosure • Operate from external 12 VDC battery and/or power supply. ~12 (+48) watts power • Battery operation: 48+ hours (w/out cooling) 20+ hours (with cooling) • Lightweight (10 lbs) • ¼ wave ground plane antenna (Ch. 8 shown; 180-186 MHz) • Connected to receiver in box by coaxial cable • Other external connectors: GPS antenna, ethernet, 12 VDC

More Related