Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New method strikes an improvement in lightning predictions

07.11.2002


A new lightning index that uses measurements of water vapor in the atmosphere from Global Positioning Systems has improved lead-time for predicting the first lightning strikes from thunderstorms. The index will help greatly aid NASA Space Shuttle launches at Kennedy Space Center, Fla, and other commercial and U.S. Department of Defense launches from Cape Canaveral Air Force Station, Fla.



"Better forecasting and more advance warning of lightning strikes will help reduce the delays or cancellations of shuttle launches from Kennedy Space Center (KSC)," Steven Businger of the University of Hawaii, Honolulu, said. Nearly 75% of all space shuttle countdowns between 1981 and 1994 were delayed or scrubbed, with about one-half of these due to weather.

The new Global Positioning System (GPS) Lightning Index combines data on the changing amount of water vapor in the atmosphere from a GPS receiver site with other meteorological data. One GPS receiver is located at the KSC on Florida’s east coast.


"According to the National Lightning Detection Network, the region where KSC is located has one of the highest lightning flash densities in the country, which makes this new Index extremely valuable," said Robert A. Mazany, also of the University of Hawaii.

Mazany and Businger worked with Seth Gutman at NOAA’s Forecast Systems Laboratory in Boulder, Colo., and William Roeder at the 45th Weather Squadron, Patrick Air Force Base, Fla., on the new GPS Lightning Index.

Warm moist air from the Atlantic Ocean and Gulf of Mexico provides the needed fuel for summer thunderstorms occurring almost daily over Florida. Southwest airflow accounts for two-thirds of the lightning strikes during the summer at KSC. Southwest flow collides with the east coast sea breeze and forces the warm moist air to suddenly rise and form thunderstorms over east central Florida. Then those same southwest winds push the thunderstorms eastward over KSC.

It’s important to look at water vapor in thunderclouds because water and ice molecules help to create the positive and negative charges in a thundercloud that generate lightning. Warmer air tends to hold more water droplets. When there is enough of a difference in the positive and negative charges in a cloud, lightning results.

An important weather challenge is to forecast lightning within a 20 mile radius of the launch complexes, 1-8 hours before a first strike, depending on the operation being supported. For instance a Shuttle landing requires a 90 minute lightning forecast, whereas the movement of solid rocket boosters requires a four hour forecast, and the movement of the Shuttle to the launch pad requires an 8 hour forecast. Benefits of better forecasts include the safety of personnel and protection of multi-billion dollar rocket launching systems, payloads, and supporting infrastructure. Accurate lightning forecasts can save $1M by avoiding either a 24 hour launch delay or the need to land the Space Shuttle at another facility and transport it back to KSC.

Businger said that data from the 1999 summer thunderstorm season was used to test the Index. The Index combines four predictors, including a prediction tool of atmospheric electric charge, the amount of water vapor detected in a cloud or air mass, the change in the amount of that water vapor over 9 hours, and a scale called the "K Index" that predicts how unstable the air will become.

During initial testing, the new index improved the lead-time for lightning strikes by nearly 10% at the Kennedy Space Center. When Businger matched the index with meteorological conditions from the summer of 1999, results revealed a 26% decrease from the KSC’s previous season’s false alarm rates.

The GPS Lightning Index provides useful guidance to forecasters for preparing lightning forecasts, when combined with other resources such as radar and satellite data. Further testing will continue to consider using the index to also forecast related weather hazards such as heavy rain and flash flood events.

The article, "A New Lightning Prediction Index That Utilizes GPS Integrated Precipitable Water Vapor," appears in the October 2002 issue of the American Meteorological Society’s Weather and Forecasting.

This research was supported by the U.S. Air Force and NOAA. Additional funding was provided by NASA and the Department of the Navy, Office of Naval Research under the Pacific STARNET program.

Rob Gutro | EurekAlert!
Further information:
http://www.gsfc.nasa.gov/topstory/20021031lightning.html

More articles from Earth Sciences:

nachricht New plate adds plot twist to ancient tectonic tale
15.08.2017 | Rice University

nachricht Global warming will leave different fingerprints on global subtropical anticyclones
14.08.2017 | Institute of Atmospheric Physics, Chinese Academy of Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>