Tamer Al-Alami
996423
Mapping Lightning Strikes in
KSA
“Using numerical methods as a tool”
‫‪Verses from Quran‬‬
‫(صم بكم عمى فهم ال يرجعون ‪ .‬أو كصيب من السماء فيه ظلمات ورعب‬
‫وبرق يجعلون أصابعهم في ءاذانهم من الصواعق حذر الموت وهللا محيط‬
‫بالكافرين ‪ 0‬يكاد البرق يخطف أبصارهم كلما أضاء لهم مشوا فيه وإذا‬
‫عليهم قاموا ولو شاء هللا لذهب بسمعهم وأيصارهم إن هللا على كل أظلم‬
‫شيء‬
‫__________________________________________‬
‫(وإذ قلتم يا موسى لن نؤمن لك حتى نرى جهرة فأخذتكم الصاعقة وأنتم‬
‫تنظرون)‬
Lightning Definition
• Abrupt electric discharge from cloud to
cloud or from cloud to earth accompanied
by the emission of light
• Flash of light that accompanies an electric
discharge in the atmosphere which can
scintillate for a second or more
Facts
• A lightning bolt can carry 30,000 A at several
hundred million V.
• In the average year, lightning strikes the US about
20 million times. Florida is easily the national
lightning Mecca
• Even a modest storm cloud can generate the
energy of a small nuclear power plant (a few
hundred MW)
• Temperature of lightning's return stroke can reach
50,000 deg F , hotter than the surface of the sun is
~ 11,000 F)
Lightning Clip
Stroke mechanism
Advantages of Lightning
1. Research indicated that it may be a very
good indicator of the strength of
convective storm systems
2. Timely hazardous weather & tornado
warnings
3. Improved forest fire & wild-land fire
management
Disadvantages
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•
•
•
Fires (lighting bolt, heating effect)
Injury
Damage
Destruction
Examples of Disadvantages
• Telecommunications firm shut down
• Burn chemical plant
• Millions of dollars of petrochemical
products & facilities are destroyed each
year by lightning-related phenomena in
many parts of the world while lives are lost
when these facilities are ignited or explode
Mathematical equations
The Avg ground flash density may be estimated
using:
Td = # of thunderstorm days / yr or keraunic level
Mapping
• It is helpful to construct a visual
representation of lightning strike densities
in countries such as Saudi Arabia in order to
locate areas which are most likely to be
stroked & those which are not
Lightning map
Lighting map
Lightning map of Saudi Arabia
Importance of Map
Comparing the lightning map to locations of
Transmission lines illustrates importance
Animation for Lightning Map
Mapping example
Early Mapping Example
Lightning Detection Systems
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Lightning Imaging Sensor (LIS)
Optical Transient Detector (OTD)
Lightning Mapper Sensor (LMS)
Lightning Detection and Radar (LDAR)
Aviation detection
Lighting imaging sensor (LIS)
• The LIS is a science instrument aboard the
TRMM Observatory, which was launched
on 28 November 1997 from the
Tanegashima Space Center in Japan
Lighting imaging sensor (LIS)
• has a staring imager optimized to locate & detect
lightning with storm-scale resolution (4 to 7 km)
over a large region (600 x 600 km) of Earth's
surface.
• TRMM Satellite travels a distance of 7 km / sec as
it orbits Earth, allowing LIS to observe a point on
Earth or a cloud for ~ 90 sec as it passes overhead,
long enough to estimate flashing rate of most
storms
Lighting imaging sensor (LIS)
 Enables detection of distribution &
variability of total lightning:
• Cloud-to-cloud
• Intra-cloud
• Cloud-to-ground
Lighting imaging sensor (LIS)
•
1.
2.
3.
The instrument records:
Time of occurrence
Measures the radiant energy
Determines the location of lightning
events within its field-of-view
Lighting imaging sensor (LIS)
• Data from this sensor is used to study
mesoscale phenomena such as:
• Storm convection
• Dynamics
• Microphysics
Lighting imaging sensor (LIS)
• A Real Time Event Processor (RTEP),
inside the electronics unit, used to
determine when a lightning flash occurs,
even in presence of bright sunlit clouds
• 90% detection efficiency
LIS
• This is the latest
lightning map
obtained using OTD
Nov 31, 2003
• Based on: data sheets
Optical Transient Detector (OTD)
• Highly compact combination of optical &
electronic elements developed by NASA
capable of detecting the momentary changes
in an optical scene which indicate the
occurrence of lightning
OTD
• OTD was launched on April 3, 1995 aboard
the MicroLab-1 satellite into a near polar
orbit at an inclination of 70 deg with respect
to the equator
Optical Transient Detector (OTD)
• Advantages:
1. Gather lightning data under daytime
conditions as well as at night
2. Provides much higher detection efficiency
& spatial resolution than has been attained
by earlier lightning sensors
OTD
• The OTD detects lightning flashes during
both day & nighttime conditions with a
detection efficiency ranging 40% - 65%,
depending on external conditions such as
glint & radiation
• Unsuitable for studying localized weather
Optical Transient Detector (OTD)
• 100-deg field of view, it surveys virtually all
areas of the globe where lightning normally
occurs
OTD
• "Flashes" are determined by comparing the
luminance of adjoining frames of OTD
optical data.
OTD continue
• If the difference is more than a specified threshold
value, an "event" is recorded.
• One or more adjacent events in the same 2ms time
frame is recorded as a "group".
• One or more groups within a sufficiently small
time period are classified as a "flash".
• These are grouped into "areas" if there are one or
more sufficiently separated from existing areas
Contributions of OTD
• Discovery of potential lightning indicators for
application to more timely hazardous weather &
tornado warnings
• Use of lightning as a proxy for detecting intense
atmospheric convection
• Production of the most complete & detailed maps
of the global lightning distribution
• Discovery that the global flash rate is approx 40
flashes / sec < ½ of the widely accepted estimates
dating back to 1925
Lightning Mapper sensor (LMS)
• Sensor, capable of continuously mapping lightning
discharges during both day & night, with a spatial
resolution of 10 km, in geostationary orbit.
• It is capable of detecting & locating both cloud-toground & intra-cloud discharges with high spatial
resolution & detection efficiency, (storm-scale
resolution) over large areas of the Earth's surface
Lightning Mapper sensor (LMS)
• A Lightning Mapper Sensor would be
capable of detecting all types of lightning
phenomena, and will provide near uniform
spatial coverage
Lighting Detection & Ranging
(LDAR)
• Network of lightning-monitoring stations at
Kennedy Space Center used for measuring
& indicating 3D locations & times of
lightning flashes that have occurred within
distances up to 10s of km’s
Lighting Detection & Ranging
(LDAR)
• The position from which a signal originated
(presumed location of lightning flash) can
be computed from the speed of light, the
differences among the times of arrival of the
signals, and known positions of stations
Advantages of LDAR
 Sensitivity
it detects & locates essentially all lightning,
including inter- & intra-cloud strokes
Detects earlier than other systems
more comprehensive info on the evolving
3D distribution of lightning activity in the
vicinity
Continue Advantages
• A typical commercial system locates 1 pt / flash or
return stroke, whereas for one flash, the LDAR
system locates an avg = 200 pts, covering an
average ground A = 11.4 km2.
• Commercial lightning-monitoring systems
generally provide only 2D location data with
errors = 2 km, whereas the LDAR provides radarlike 3D location data with errors = 150 m.
LDAR system
Continue
• Trend toward micro-miniaturization in
electronic systems development brings an
increasing sensitivity to transient
phenomena. Transients of < 3 V peak or
energy levels as low as 10-7 J can damage
or “confuse” these systems & their
components.
Lightning Probability
• One of the main driver's of lightning activity is
temperature. The closer to the equator, the more
risk of experiencing lightning
• Proximity - the closer to the storm cell (cloud), the
greater the field intensity & risk
• Degree of exposure – the closer it sticks out with
little cover from surroundings, the greater the risk
for a strike
Aviation detection
• Rocket-triggered lightning
Aviation detection
• Provide detailed info of the discharge's
characteristics
• provide in-cloud measurements of
thunderstorms
• Replaces optical measurements of in-cloud
lightning which are severely affected by
light scattering from water droplets within
the cloud
Aviation detection
• U-2 & ER-2 high altitude airplanes have
been used to study the electrical & optical
characteristics of lightning activity in
thunderstorms.
• Flying at an altitude of 20 km at speeds of
200 m/s, are capable of flying over very
large thunderstorms
• ER2 is better
Aviation detection
Aviation detection
U2 high altitude research craft
Future of Lighting Detection
• The future looks very promising with new
detection methods to be developed.
• Research currently is done on ways to apply
Fourier for the purpose of detection
Thank you
Any questions are welcomed