History, Detection Methods, and Purpose Matt Mahler – METR 2413

Getting Started Informing those who want to know about the primary source of lightning detection, but don’t have a lot of time. Coverage: –A brief history –Why NLDN exists –How NLDN works Cool lightning pictures! © Michael Fewings

Where It All Began Originated in the mid-1970s at the University of Arizona Founded by Dr. E. Philip Krider, Dr. Burt Pifer, and Dr. Martin Uman – who all researched lightning behavior and properties. After over a decade of hard work, they formed the United States’ only national lightning detection system. Since 1989, it has monitored the million cloud-to ground lightning strikes (per year!) in the contiguous 48 states (a.k.a. “A Wide-area Lightning Information System”) Operational 24 hours a day, 7 days a week, 365 days a year.

So…What is it? & What does it do? “The most sophisticated lightning detection and location system in the world.” Instantaneously detects electromagnetic signals given off when lightning strikes the ground. Closely examines lightning activity as a storm intensifies and moves, which in turn… Informs weather forecasters and weather-sensitive businesses when a storm begins to generate lightning so other dangerous elements can be monitored.

How Does It All Work? “Lazy Lightning” © Michael Fewings Return Lightning Stroke from 2 LPATS sensors & 3 IMPACT sensors

3 Different Components The Sensor Component The Central Processor Component The Display Software Component (IMPACT ESP™) (LP Series) (LTraX®) Photos © NLDN, Global Atmospherics, Inc.

Sensor #1 – IMPACT ESP Specifications –ESP (Enhanced Sensitivity & Performance) –Locates and detects cloud & cloud-to-ground lightning –Currently 47 sensors in the U.S. –Uses Magnetic Direction Finding (MDF) and Time-of- Arrival (TOA) technology Photo © NLDN, Global Atmospherics, Inc.

Impact ESP – Why It’s Good Combined proven accuracy of Magnetic Detection Finding (MDF) technology with Time-of-Arrival (TOA) technology Greater location accuracy & detection efficiency Most accurate location discharge estimates Pinpoint accuracy within less than 500 meters (1,640 feet) Works with only 2 sensors Locates and detects more cloud-to-ground events than any other available product!

Sensor #2 – LPATS IV Specifications –LPATS (Lightning Positioning and Tracking Sensor) –Detects electric field signature of lightning discharges –Currently 59 upgraded LPATS IV sensors in the U.S. –Measures absolute arrival time of the lightning discharges Photo © NLDN, Global Atmospherics, Inc.

LPATS IV – Why It’s Also Good Unprecedented locational accuracy of less than 500 meters (1,640 feet) Detects 95% or more of all cloud-to-ground lightning flashes Easier remote sitting and installation than any other sensor Sensor self-testing System’s reliability among the best Confidence in overall data quality

Location of NLDN Lightning Sensors Δ – IMPACT sensors Ο – LPATS sensors Image © NLDN, Global Atmospherics, Inc.

Central Processor & Display Software Component Images © NLDN, Global Atmospherics, Inc. LTraX ® - real-time lightning tracking software for Windows ® StormTraX ™ - Unix ®-based lightning tracking display software VIS ™ - Video Information System – DOS based lightning display software LP Series - Computes lightning location from raw sensor data & monitors sensor status DA 2000 ™ (Distribution and Archive) - Receives real-time lightning data from LP Series NM 2000 ™ (Network Management Module) – Verifies network performance

Putting It All Together… Step 1: Sensors transmit lightning data to satellite Step 2: Satellite relays information to earth station Step 3: Data is transmitted via land-lines Step 4: NCC processes data Step 5: Processed data is relayed back to satellite Step 6: Lightning data is played within seconds of occurrence Image © NLDN, Global Atmospherics, Inc.

…For Storms Like This “Big Strike” © Michael Fewings

Who Uses NLDN Data? National Weather Service (NWS) Federal Aviation Administration (FAA) The Weather Channel ® PGA Tour ® Major Power Companies International and regional airports Thousands of businesses nationwide Lightning over OKC © Gene Moore

Safety First There is no reason to be caught off guard by a thunderstorm Outdoor sports + Thunderstorms = Deadly Combination Get: out of the water, out of open spaces, away from trees Unplug expensive electronics Avoid corded telephones Wait to use plumbing Stay away from windows Don’t let being uninformed jeopardize being safe.

“Anvil Crawlers” silhouette the skyline of downtown Dallas. © Samuel D. Barricklow

Image © The Weather Prediction

Resources (Information & Photo) Ahrens, C. Donald. “Meteorology Today.” Brooks/Cole Publishing, 2000 Ed. Page 401. May 4, Barricklow, Samuel D. Storm Chase Homepage. May 3, Cummins K.L., Krider, E. Philip, Malone, Mark D., "The U.S. National Lightning Detection Network® and Applications of Cloud-to-Ground Lightning Data by Electric Power Utilities", IEEE Transactions on Electromagnetic Compatibility, Vol. 40, No. 4, November Cummins K.L., Murphy, M.J., Bardo, E.A., Hiscox W.L., Pyle R.B., and Pifer A.E., "A combined TOA/MDF technology upgrade of the U.S. National Lightning Detection Network", J. Geophys. Res., Vol. 103, No. D8, Pages , April 27, Fewings, Michael. Strike One. October 13, Global Atmospherics, Inc. Lightning Storm.com. May 4,

Resources (Continued) Kiesling, Douglas. Lightning Boy. April 24, _IMG0004g.htm (opening background) Krythan, Tim. Tim’s Page of Weather Stuff. June 15, (slide background) Moore, Gene. Chase Day. May 4, Murphy, M.J., Cummins, K.L., "Early Detection and Warning of Cloud-to- ground Lightning at a Point of Intererst", 80th American Meteorological Society Meeting, Long Beach, CA, January 8-14, The Weather Prediction. Weather Prediction Education. May 4,