Rudlosky and team set to evaluate lightning data

COLLEGE PARK, Md. – Scott Rudlosky, NOAA physical scientist and ESSIC visiting assistant research scientist, recently returned from São Paulo, Brazil, where he worked with Research Scientist Rachel Albrecht, Associate Professor Carlos Morales, Doctoral Candidate Evandro Anselmo, and Technician João Neves as part of the CHUVA field campaign to evaluate methods for measuring and mapping lightning activity.

In the coming months, the scientists will reunite at ESSIC/CICS to evaluate lightning data obtained during their trip. Dr. Albrecht will visit ESSIC/CICS within the next month, while Gomez and Neves will visit during the summer months.

From early October through the first week of November 2011, the team visited various sites around São Paulo to install lightning sensors. The team installed physical sensors outdoors and computers inside.  Data was then gathered from November 1, 2011 through March 31, 2012.

The scientists are now working with an international team to co-locate and evaluate observations from several networks that map lightning using different technology.

Located in Brazil, the CHUVA field campaign has five different Intensive Operation Period (IOPs), designed to monitor different areas of the country. This large-scale study seeks to evaluate the various thunderstorms types that produce precipitation in Brazil.

“In São Paulo, they happen to have satellite coverage from an important European satellite, which is very similar to a satellite that we’re (NOAA) going to launch in late 2015,” Rudlosky said.

The NOAA satellite set to launch in 2015 will have a Geostationary Lightning Mapper (GLM), which maps lightning activity both in the clouds and when it strikes ground. This new satellite will be in geostationary orbit – rotating at the same speed as the earth – providing NOAA with continuous lightning observations throughout the Western Hemisphere.

Rudlosky also helps maintain a Lightning Mapping Array (LMA) network in Washington, D.C., which is very similar to the network recently deployed in São Paulo. These networks are used to create proxy datasets, and can also be overlaid with other networks in the United States, Europe, and across the globe.

During May and June 2012, Dr. Albrecht will spend several weeks in Alabama and Maryland helping to evaluate the lightning data. Albrecht is the project coordinator, and works for INPE, the Brazilian equivalent of NASA. Rudlosky and Dr. Albrecht will continue to evaluate these data, along with Neves, Gomez, and Morales of the Universidade de São Paulo, and a Huntsville, AL research team led by Senior Scientist Monte Bateman of the Universities Space Research Association.

“Now we need to evaluate the data. That’s where GOES-R comes in,” Rudlosky said. “GOES-R is the main scientific objective … we want to see if any of these networks will work for what we want to use them for, and that’s preparing users for the upcoming GLM data.”

Rudlosky said lightning can often help determine where the heaviest precipitation occurs, which is important when forecasting weather hazards or keeping records of precipitation.

Intra-cloud lightning – lightning occurring between clouds or within a single cloud without coming to the ground – is particularly tied to severe weather.

“And since the intra-cloud lightning is so closely tied to severe weather, they’re actually using it to forecast severe weather and predict severe weather in the short-term,” Rudlosky said.

Rudlosky said he also hopes the data is useful for studies outside the scope of the proposed study.

“There are so many different pieces and parts of a lightning flash that it’s hard to [agree on a definition for] a lightning flash,” Rudlosky said. “To get a really accurate flash count – how many flashes happen during that period of time – you have to make assumptions on what space and time criteria should be used to group the pieces together.”

Since there are ten networks in one place, this may help create a more uniform definition of what a lightning flash actually is, but Rudlosky said that is a tall task.

Rudlosky said he and Dr. Albrecht will both have presentations at the 2012 NOAA Satellite Science Week Conference during the first week of May.

“She doesn’t have the final results yet, but she’s going to present the basic framework so we can gather feedback,” Rudlosky said. “And so based off of what people suggest next week, we’ll set out a more clearly defined plan.”

Meanwhile, Rudlosky’s focus is on larger spatial scales and longer time scales.

“I’m evaluating how the ground-based networks perform relative to an existing lightning sensor on a low-earth orbiting satellite,” Rudlosky said.

Rudlosky, who received his Master’s (2007) and Ph.D. (2011) in Meteorology from Florida State University, said he initially went to school to study hurricanes. But he became interested in lightning from what he described as a random series of events.