PICCOLO Campaign takes OU Atmospheric Scientists to the Atlantic

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NORMAN, OKLA. – As part of a National Science Foundation-funded effort to better understand storms in the tropics, James Ruppert recently sailed across the Atlantic Ocean for a month-long science cruise. Ruppert, a professor at the University of Oklahoma School of Meteorology, is a lead researcher on the PICCOLO project (Process Investigation of Clouds and Convective Organization of the atLantic Ocean), one of eight sub-campaigns that make up the ORCESTRA campaign, an international cross-institution and multi-funding-sourced effort to better understand what atmospheric mechanisms influence tropical convection.

Ruppert says the overarching goal of ORCESTRA is to improve the understanding of what controls the organization of clouds and convective storms in the tropics and what the implications of this organization are for weather and climate.

ORCESTRA, an acronym for Organized Convection and EarthCare Studies over the Tropical Atlantic, included sea-borne and air-borne teams utilizing various observation instrumentation to achieve its goals. The sea-borne crew, of which Ruppert was a part, traveled on the RV Meteor, Germany’s third-largest research vessel. Three aircraft, a satellite and the Barbados Cloud Observatory were also part of the mission. The campaign serves to assess the performance of the newly launched EarthCARE satellite, which will collect important new global cloud observations.

Science at Sea and on Land

While at sea, the team experienced a wide range of weather to collect observations, from many days of clear skies to less-than-clear skies. “We sampled deep thunderstorms, many shallower precipitating clouds and a wide range of different modes of cloud organization,” said Ruppert. “Being able to literally experience the weather we’re studying from the observation deck of the ship was extremely rewarding.”

The PICCOLO team added SEA-POL, Colorado State University’s Sea-Going Polarimetric Radar, to the observation instrumentation list. SEA-POL is designed specifically for sea-going field campaigns and has dynamic platform stabilization that responds to a ship's motion while it collects data.

Radiosondes—small instruments sent into the atmosphere by weather balloons—helped provide a baseline for land observations and were coordinated with the dropsondes dropped from the HALO research aircraft. 

Using SEA-POL, the PICCOLO team collected detailed information about precipitation, the dynamics within convective storms and cloud microphysics. The PICCOLO team also assisted with balloon launches.

Several student interns from the Caribbean Institute for Meteorology and Hydrology joined the daily ORCESTRA weather briefings both to provide local expertise and learn about the science objectives of the field campaign. Led by Chelsea Nam (Florida State University) and Bjorn Stevens (Max Planck Institute for Meteorology), members of the PICCOLO team also visited CIMH and the University of West Indies to discuss ORCESTRA and PICCOLO science goals.

Students in the Field

Emily Luschen, Mac Syrett, and Colin Welty, students from the School of Meteorology, joined Ruppert partway through the project. On Sept. 21, they met with the team in Barbados to provide support for weather balloon launches.

“We specialized in launching radiosondes at the Barbados Cloud Observatory,” said Colin Welty, a graduate research assistant in the School of Meteorology. “Mac, Emily and I had the opportunity to collectively launch 15 radiosondes as part of the process. Additionally, we were able to assist with forecasting for the flights for the HALO aircraft and gave weather briefings to several scientists.”

“It’s been extremely rewarding to be part of such an energized and enthusiastic community that’s rallying around the scientific opportunities provided by this large campaign,” said Ruppert.

Learn more about PICCOLO, ORCESTRA and Ruppert’s Convective Storm Dynamics Group.