Dropsondes carry instruments that measure temperature, humidity, air pressure, and wind speed. They are dropped on small parachutes from aircraft.
Image courtesy of UCAR.

Instruments in the VOCALS Field Campaign

Scientists use a broad array of instruments during the VOCALS field campaign to measure various aspects of the atmosphere and the oceans. These sensors are carried on aircraft and ships, orbit overhead aboard satellites, and are stationed on buoys in the ocean.

Radar is used to determine wind speed, to detect rainfall, and to determine the sizes of water droplets in clouds and drizzle. LIDAR, which is similar to radar but uses laser light instead of radio waves, detects and measures aerosol particles and the boundaries of clouds.

Radiosondes and dropsondes are instrument packages carried aloft on balloons or dropped on parachutes from aircraft. They include instruments for measuring pressure, altitude, temperature, humidity, and wind speed and direction.

Various cameras and imaging systems on aircraft and satellites take "pictures" in visible and infrared wavelengths, of clouds and the sea surface. Radiometers measure the amount of sunlight reflected from cloud tops, infrared radiation emitted at various levels in clouds and the atmosphere, and the degree to which clouds are transparent or opaque. Spectrometers detect various chemicals in the atmosphere and in aerosols, including particles that serve as cloud condensation nuclei.

A ship-towed sensor platform carries various instruments that measure temperature, salinity, pressure, dissolved oxygen, and chlorophyll content in the ocean. A special kind of sonar collects data on the velocity and direction of ocean currents.

Last modified June 17, 2010 by Becca Hatheway.

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