Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rapid-scanning doppler on wheels keeps pace with twisters

02.06.2005


A multibeam Doppler radar that can scan tornadic storms every 5 to 10 seconds is prowling the Great Plains through June 30 in search of its first close-up tornado. Engineers at the National Center for Atmospheric Research in Boulder helped build the Rapid-Scan Doppler on Wheels (DOW).



Together with a powerful analysis technique pioneered by NCAR scientist Wen-Chau Lee, the radar--newly enhanced for its first full spring of thunderstorm tracking--promises the most complete picture to date of tornado evolution.

The radar is being deployed this spring, along with another DOW unit, by NCAR scientific visitor Joshua Wurman (Center for Severe Weather Research, or CSWR) from a temporary base in Hays, Kansas.


Most Doppler radars transmit only a single beam, which takes about 5 minutes to make the vertical and horizontal scans needed for a three-dimensional storm portrait. But tornadoes can develop or dissipate in a minute or less. With its 5- to 10-second resolution and close range, the Rapid-Scan DOW can detail these critical steps in tornado behavior.

"The development of the Rapid-Scan DOW is an important advancement for meteorological research," said Steve Nelson, director of NSF’TMs physical and dynamic meteorology program, which funded the radar’TMs development. "The new radar will result in unique measurements of rapidly evolving meteorological phenomena such as tornadoes."

The first DOW was deployed in 1995. Since then, Wurman’TMs group has collected data on roughly 100 tornadoes, intercepted the eyes of eight hurricanes, and profiled forest fires. On May 3, 1999, DOW measured a world-record wind speed of 301 miles per hour just above ground level in an Oklahoma tornado.

As part of a $1.6 million NSF grant, Wurman and Curtis Alexander (University of Oklahoma) are analyzing the entire DOW data set on tornadoes to uncover new information, such as how closely tornado diameters are correlated with top wind speeds. Other scientists at OU and Pennsylvania State University will also carry out DOW analyses through the grant. "We can’TMt answer even the basic questions about typicalTM tornadoes right now, such as how strong their winds are," says Wurman. "By looking at these 100 cases, we hope to understand the distribution of features across many types of tornadoes." These findings could be compared to storm types to help produce better warnings, Wurman adds.

Wurman and Lee plan to select a few tornadoes for more in-depth study. They’TMll use a technique called velocity track display (VTD), originally developed by Lee for hurricane studies, that allows scientists to extract three-dimensional winds using data from a single Doppler radar. The two scientists have already used VTD with DOW data to analyze a large and intense tornado that struck Mulhall, Oklahoma, in 1999. They discovered a central downdraft, similar to the eye of a hurricane, surrounded by a ring of updrafts blowing at near-hurricane force, with multiple small vortices rotating around this ring.

The structure found in the Mulhall tornado had been observed for many years in lab experiments and computer models, but it had never been verified by radar data. Lee expects to find a simpler structure in weak tornadoes, without the central downdraft observed in Mulhall.

"We want to use DOW data to analyze more tornadoes of different sizes and intensities and see how they compare to our laboratory work and our model results," Lee says.

Dubbed ROTATE-05, the field work is supported by the National Geographic Society. Design and construction of the Rapid-Scan DOW is funded by the National Science Foundation, which is also NCAR’TMs primary sponsor.

Opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of the National Science Foundation.

Anatta | EurekAlert!
Further information:
http://www.cswr.org
http://www.ucar.edu

More articles from Ecology, The Environment and Conservation:

nachricht How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>