A local Alabama science teacher recently had the opportunity to visit and take part in the DC3 field project with the ground-based facilites at the University of Alabama – Huntsville (UAH). Enjoy her first-hand account of learning about the DC3 project and participating in research operations.
By Kelly Ford
East Limestone High School, Athens, Alabama
Science Teacher and UCAR/RETI participant
A science team from the University of Alabama in Huntsville has been given the opportunity to participate in a field project with NCAR along with science groups from Colorado and Oklahoma/Texas. The project is called DC3 (Deep Convective Clouds and Chemistry) studies how the atmospheric composition changes as a result of a thunderstorms. Some ground-based research operations consist of launching weather balloons near a position that will possibly contain a thunderstorm in a few hours, and then more are launched after the thunderstorm passes.
These weather balloons carry radiosondes that measure temperature, barometric pressure, dew point, wind speed and direction. They are also able to measures the lower free convection (LFC) level. When a radiosonde is released, the weather balloon carries it upwards at about 385 meters/minute and the balloon bursts at an altitude of around 40,000-70,000 feet.
A Day in the Field :: Tuesday, May 29 2012
8:30AM – Conference room meeting at UAH
Every operation morning, the groups from Alabama, Oklahoma/Texas, Colorado, and the flight team from Salina, Kansas, hold a joint teleconference to discuss weather conditions, equipment status, and the plan for the day. At this Tuesday meeting, the decision was made to fly the planes from Salina to Alabama because of the probability of storms in the North Alabama area.
10:00AM – Head to Ardmore rest area to prepare for 12:00 launch
Since storms were anticipated in to begin in the early afternoon, the decision was made to launch a radiosonde near the Alabama/Tennessee state line. The rest area exit on I-65 had been used by this group and it was decided to use this location again. The radiosonde van and a chase car were loaded and I rode along with the team.
11:00AM – Take stock in van
As time came closer for launch, the van was opened and an inventory made of materials needed for possible launches from this rest area. Preparations were made with the balloon, radiosonde, parachute, and fuel tank for the helium. It was very hot and humid. There was some convection beginning just south of the launch position but nothing very promising. The balloon was inflated, equipment attached, and the team was very generous in letting me release the first balloon of the day.
11:56AM – I got to launch a weather balloon!!
I was very surprised at how quickly the balloon gained altitude. We were only able to follow it visually for a couple of minutes. After a launch, the team follows the trajectory and monitors the data being sent from the radiosonde with a laptop mounted in the front of the van. Danielle is monitoring the data in the following picture while Mario and Curtis try and stay out of the heat. Data is loaded very quickly from the radiosonde to the DC3 project catalog for access by teams working on this and affiliated projects.
After a launch and when the team is satisfied that the data is loading properly from the radiosonde, the team waits for instructions from the planning group at UAH. When we left the morning meeting, the plan had been to have the planes in the North Alabama area by around 3:30. Word was later sent that the planes had been prepared to come but were told by air traffic control in Atlanta that they would not be allowed in the Memphis or Atlanta air space due to heavy re-routing traffic throughout the Southeast US caused by strong storms associated with Beryl. I could tell that the team was disappointed. It was going to be a good day for data but due to circumstances outside of their control, the afternoon activities fell through. (The planes used for this field research need to stair step, fly spirals, and fly irregular patterns so are not able to file an exact flight plan.) As the planes are flying these irregular patterns, they are finding the top and bottom of the storm while measuring the atmosphere’s composition of NOx, CO, CO2, CH4, and O3 as these go into and out of convective storms.
4:15PM – Head back to UAH for a second radiosonde launch
The team was told to head back to UAH for an afternoon plan revision. It was decided to launch a second radiosonde from the UAH site as a second pre-storm evaluation. This data was also needed by the Atmospheric Boundary Identification and Delineation Experiment (ABIDE), another group working with DC3. ABIDE looks for the transition boundary in storms and studies why and how thunderstorms initiate.
As an aside, I have really enjoyed observing (and helping out where I could) with the radiosonde team. This group of young meteorology students has a passion for research work, is dedicated to doing things well, work well as a team, and is very knowledgeable about this field of study. I joined them again on Thursday for a launch from Moulton, Alabama, and had hoped to join them again, but good convection never developed. This has been a great experience for me and I hope to join them again before heading to Colorado for the NCAR Research Experience Teacher’s Institute (RETI) in July.