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 Fossil coral reefs show sea level rose in bursts during last warming
19.10.2017 | Rice University

nachricht NASA finds newly formed tropical storm lan over open waters
17.10.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>