1 / 50

Mapping Lightning Strikes in KSA

Mapping Lightning Strikes in KSA . Tamer Al-Alami. 996423. “Using numerical methods as a tool”. Verses from Quran .

lelia
Download Presentation

Mapping Lightning Strikes in KSA

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. Mapping Lightning Strikes in KSA Tamer Al-Alami 996423 “Using numerical methods as a tool”

  2. Verses from Quran (صم بكم عمى فهم لا يرجعون . أو كصيب من السماء فيه ظلمات ورعب وبرق يجعلون أصابعهم في ءاذانهم من الصواعق حذر الموت والله محيط بالكافرين 0 يكاد البرق يخطف أبصارهم كلما أضاء لهم مشوا فيه وإذا أظلم عليهم قاموا ولو شاء الله لذهب بسمعهم وأيصارهم إن الله على كل شيء __________________________________________ (وإذ قلتم يا موسى لن نؤمن لك حتى نرى جهرة فأخذتكم الصاعقة وأنتم تنظرون)

  3. 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

  4. 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)

  5. Lightning Clip

  6. Stroke mechanism

  7. Advantages of Lightning • Research indicated that it may be a very good indicator of the strength of convective storm systems • Timely hazardous weather & tornado warnings • Improved forest fire & wild-land fire management

  8. Disadvantages • Fires (lighting bolt, heating effect) • Injury • Damage • Destruction

  9. 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

  10. Mathematical equations The Avg ground flash density may be estimated using: Td = # of thunderstorm days / yr or keraunic level

  11. 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

  12. Lightning map

  13. Lighting map

  14. Lightning map of Saudi Arabia

  15. Importance of Map Comparing the lightning map to locations of Transmission lines illustrates importance

  16. Animation for Lightning Map

  17. Mapping example

  18. Early Mapping Example

  19. Lightning Detection Systems • Lightning Imaging Sensor (LIS) • Optical Transient Detector (OTD) • Lightning Mapper Sensor (LMS) • Lightning Detection and Radar (LDAR) • Aviation detection

  20. 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

  21. 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

  22. Lighting imaging sensor (LIS)  Enables detection of distribution & variability of total lightning: • Cloud-to-cloud • Intra-cloud • Cloud-to-ground

  23. Lighting imaging sensor (LIS) • The instrument records: • Time of occurrence • Measures the radiant energy • Determines the location of lightning events within its field-of-view

  24. Lighting imaging sensor (LIS) • Data from this sensor is used to study mesoscale phenomena such as: • Storm convection • Dynamics • Microphysics

  25. 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

  26. LIS • This is the latest lightning map obtained using OTD Nov 31, 2003 • Based on: data sheets

  27. 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

  28. 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

  29. Optical Transient Detector (OTD) • Advantages: • Gather lightning data under daytime conditions as well as at night • Provides much higher detection efficiency & spatial resolution than has been attained by earlier lightning sensors

  30. 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

  31. Optical Transient Detector (OTD) • 100-deg field of view, it surveys virtually all areas of the globe where lightning normally occurs

  32. OTD • "Flashes" are determined by comparing the luminance of adjoining frames of OTD optical data.

  33. 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

  34. 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

  35. 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-to-ground & intra-cloud discharges with high spatial resolution & detection efficiency, (storm-scale resolution) over large areas of the Earth's surface

  36. 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

  37. 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

  38. 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

  39. 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

  40. 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 radar-like 3D location data with errors = 150 m.

  41. LDAR system

  42. 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.

  43. 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

  44. Aviation detection • Rocket-triggered lightning

  45. 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

  46. 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

  47. Aviation detection

  48. Aviation detection U2 high altitude research craft

  49. 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

  50. Thank you Any questions are welcomed

More Related