Andros Island Radiosonde (Rawinsondes)
Point of Contact:
- Francis J. Schmidlin
- Code 972
- NASA/GSFC/Wallops Flight Facility
- Wallops Island, Virginia 23337
- Office Telephone: (757) 824 1618
- FAX: (757) 824 1036
- E-mail: fjs@osb.wff.nasa.gov
Brief Instrument Description of the
Andros Island Rawinsonde and Radiosondes
INSTRUMENT DESCRIPTION
Two basic instrument types are flown
- Rawinsonde with GPS winds and Loran-C winds
- Radiosonde with chilled-mirror sensor
A radiosonde is an instrument carried into the upper atmosphere by a balloon that measures pressure, temperature, relative humidity vs. time. A rawinsonde is a radiosonde tracked by navigation aids from which winds can be calculated. The sensor measurements are transmitted to a ground receiver where they are processed to provide heights and other information, as desired. Winds are measured using a navigation aid technique such as Loran-C or GPS. The radiosondes used at Andros Island are mostly GPS type radiosondes using full code-correlated transmission from up to 10 GPS satellites. This provides accurate height and wind information allowing pressures to be calculated. A smaller number of radiosondes use Loran-C. Because of the location of Andros Island relative to the Loran-C transmitters little wind information is expected from this technique. The GPS and MK-2 radiosondes typically use a carbon resistive relative humidity sensor. A limited number of chilled mirror type radiosondes will be used to obtain more accurate relative humidity profiles. These chilled mirror instruments represent the mating of an old technolgy process with a new application - accurate chilled mirror measurements using an inexpensive radiosonde.