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National Lightning Detection Network Platform Document
Summary:
The United States National Lightning Detection Network (NLDN) began at
the State University of New York at Albany as a research program using
commercially available direction finding sensors to create a 10 sensor
network. The network provided coverage for the eastern coast of the United
States from North Carolina to the Canadian border. The NLDN is
currently operated by Global Atmospherics, Inc., in Tucson, Arizona.
The NLDN has been measuring the time and location of lightning flashes
across the continental United States since 1989. The NLDN
uses more than 100 sensors to provide real time and historical data to
the electric utility industry, the National Weather Service, commercial
users, and researchers.
Table of Contents:
Source/Platform or Data Collection Environment
Overview
Source/Platform or Data Collection Environment
Long Name, Source/Platform Acronym: National Lightning Detection Network, NLDN
Source/Platform Introduction:
Collection Environment: Network of ground based antennae
Source/Platform Program Management: The NLDN began as a
research program at the State University of New York at Albany.
The importance of the network was
recognized by the electric utility industry which consequently funded
the expansion and operation of the "SUNY Network" through the Electric
Power Research Institute. The growth of commercial interest in
national-scale lightning information led to the establishment of a
commercial data service.
Source/Platform Mission Objectives: There are four principal objectives of the NLDN. The primary objective
is to locate cloud-to-ground lightning, in order to meet the growing demands
of emerging applications in the electric utilities. The second objective is
to provide the infrastructure to process and deliver both stroke
and flash information in real-time. The third objective is to improve detection
efficiency for low peak current events, down to 5 kA. The final objective is to
accomplish these first three objectives while improving long-term reliability.
Source/Platform Parameters: The NLDN is comprised of approximately 105 ground based
sensors that detect electro-magnetic signals produced by lightning discharges.
Coverage Information: The NLDN has approximately 105 sensors located throughout
the continental United States.
Attitude Characteristics: This information is not applicable to this platform.
Data Collection System: Ground based sensors detect the electro-magnetic signals
produced by lightning discharges and then transmit this information to
the Network Control Center (NCC) in Tucson, Arizona via a two-way
satellite system.
Communication Links: Very Small Aperture Satellite Terminals (VSATS)
provide the communications path between the remote sites and the NCC.
The VSAT network uses a methodology where a master hub communicates with
each of the remote VSATS. The master hub then transmits the information
to the NCC via a terrestrial link. The data arrives at the NCC via
multiple, digitally backed up, 56 kilobit/second digital lines from the
VSAT hubs.
List of Sensors/Instruments: Instruments for the NLDN are ground-based radio frequency
antennae.
Ground Segment Information
Tracking and Control: This information is not applicable to this platform.
Data Acquisition and Processing: The Network Control Center is the primary hub for all NLDN
communications, computation and archiving activity. The data to be
archived is sent to dual redundant magneto optical recording media.
Following archival, the raw data is sent to the lightning location
calculation processes. The data is sorted by sensor report times, then a
location is calculated for time coincident sensors. Quality checks are
performed for the location. The lightning solutions are then archived
and sent to the real time subscribers.
Latitude Crossing Times: This information is not applicable to this platform.
References
Cummins, K.L., et al., 1995:
NLDN'95: A Combined TOA/MDF Technology Upgrade of the U.S. National Lightning
Detection Network. Intl. Aerospace & Ground Conference
on Lightning and Static Electricity, Williamsburg, VA,
USA, Sept. 26-28, 1995.
Cummins, K.L., R.O. Burnett, W.L. Hiscox, and A.E. Pifer, 1993:
Line Reliability and Fault Analysis Using the National Lightning
Detection Network. Preprints, Precise Measurements in Power
Conference, Arlington, VA, Oct. 27-29, 1993.
Cummins, K.L., W.L. Hiscox, A.E. Pifer, and M.W. Maier, 1992: Performance
Analysis of the U.S. National Lightning Detection Network.
Proceedings, 9th International Conference on Atmospheric Electricity.
St. Petersburg, Russia. A.I. Voeilkov Main Geophysical Observatory,
Karbysheva 7, 194018, St. Petersburg, Russia.
Holle, R. H. and Lopez, R. E, 1993: Overview of Real-Time Lightning
Detection Systems and their Meteorological Uses. NOAA Technical
Memorandum ERL NSSL-102, National Severe Storm Laboratory,
Norman, Oklahoma, October 1993.
Maier, M. W., et al., 1983: Locating Cloud-To-Ground Lightning With
Wide band Magnetic Direction Finders. Presented at 5th Symposium on
Meteorological Observations and Instrumentation. Toronto, Ontario, Canada,
April 11-15, 1983.
Orville, R.E., 1994: Cloud-to-Ground Lightning Flash Characteristics in
the Contiguous United States: 1989-1991. Journal of Geophys. Res.,
Vol. 5., 10833-10841.
Reap, R.M., D.R. MacGorman, 1989: Cloud-to-Ground Lightning: Climatological
Characteristics and Relationships to Model Fields, Radar Observations,
and Severe Local Storms. Monthly Wea. Review, 117, 518-535.
Glossary of Terms
Please see the GHRC Glossary
for terms related to the GHRC and see EOSDIS
Acronyms for a general listing of terms related to the Earth Observing
System Project.
List of Acronyms
Please see the GHRC Glossary
for terms related to the GHRC and see EOSDIS
Acronyms for a general listing of terms related to the Earth Observing
System Project.
EPRI - Electric Power Research Institute
GAI - Global Atmospherics Inc.
kA - kiloAmperes
NCC - Network Control Center
NLDN - National Lightning Detection Network
SUNY - State University of New York
URL - Uniform Resource Locator
VSATS - Very Small Aperture Satellite Terminals
Document Information
Document Revision Date:
May 29, 1997
Document Review Date:
October 7, 199
Document Curator:
GHRC User Services
support-ghrc@earthdata.nasa.gov
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