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Colloquium - VanAndel

Linux at 20,000 Meters Above the Sea
National Center for Atmospheric Research

The eastern tropical Atlantic ocean is the breeding ground for the hurricanes that hit the U.S. Gulf coast and the eastern seaboard, and we don't know nearly enough about it. The area is out of range for our hurricane-monitoring aircraft, and forecasters don't have enough data to predict which disturbances will turn into hurricanes.

That's where the driftsonde project comes in. Joe VanAndel, long-time FRUUG Executive Committee member and programmer at the National Center for Atmospheric Research (NCAR) was involved in a collaboration between NCAR, the French Space Agency (CNES) and the French National Center for Scientific Research (CNRS) to develop and field driftsondes. This team of scientists and engineers launched weather balloons from Niger, Africa. The weather balloons drifted west towards the Caribbean and released dropsondes to measure atmospheric conditions.

Joe will give an overview of the driftsonde project, including how NCAR used a tiny Linux computer to control and monitor the driftsonde, consisting of a stratospheric balloon, a gondola, and an instrument package. He'll describe how NCAR monitored and controlled the gondola using an Iridium satellite link. In addition, he'll present a case study of how he used Python on the gondola computer to reprogram the equipment -- in the middle of a flight.

Some of the challenges: each sonde had to have its own heater, wrapped around its battery. The gondola supplied power to the sonde heater, until the sonde's battery was warm enough to produce enough voltage to power the sonde. It was almost like "jump starting" the sonde at 20,000 meters at temperatures of -70C. If this isn't interesting enough, Joe will be bringing a gondola, an Iridium modem, the electronics stack, and some sondes (including the much larger ones that are currently dropped from aircraft).

VanAndel is a programmer in the Earth Observing Laboratory of NCAR. He typically writes software to process and display data from weather radars, and he enjoys programming in Python. Joe is a member of the FRUUG Executive Committee. In his spare time, he enjoys bicycling, digital photography, and working with Flatirons Habitat for Humanity.

Co-sponsored by the Front Range UNIX Users Group (FRUUG).

Department of Computer Science
University of Colorado Boulder
Boulder, CO 80309-0430 USA
May 5, 2012 (14:13)