TBS

The tethered balloon system (TBS) is composed of a variety of winches, balloons, and instrumentation. The TBS normally operates up to approximately 1,500 meters above ground level (AGL). The typical balloons used are Skydoc Model #28 aerostats. The TBS is operated intermittently during missions that are typically two weeks in duration, and the instrumentation deployed varies with mission science goals and conditions.

The TBS normally operates below the lowest cloud base, where it collects in situ measurements of temperature, humidity, wind speed, wind direction, turbulence, and aerosol properties. In addition to discrete measurements of temperature and humidity, the TBS measurement suite also includes a fiber-optic-based, distributed temperature-sensing system that provides continuous profiles of thermodynamic properties.

When operating at the ARM site at Oliktok Point, Alaska, the TBS flew in clouds and also provided measurements of supercooled liquid water content and ice microphysics. In-cloud operation at Oliktok was possible because the Federal Aviation Administration (FAA) had designated a special restricted air space over Oliktok that permitted those operations. No current ARM locations have a similar feature at this time.

View the suite of baseline instruments that are typically flown on ARM’s TBS missions.

The TBS also includes a continuously operated ground station that measures surface pressure, temperature, relative humidity, and 1-minute average and gust wind speeds.