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NASA Distributed Active Archive Center (DAAC) at NSIDC

Supporting scientific study of the cryosphere

See Also

NOAA/NASA Polar Pathfinder Data at NSIDC

This product page contains links to NSIDC TOVS data sets.

NOAA/NASA Polar Pathfinder Program Description

This web page gives details about the NOAA/NASA Polar Pathfinder program.

Related Resources

NOAA TOVS Web site

This NOAA Web site provides information about the TOVS instrument along with science applications.

DAAC Data Projects: Visible/Infrared


The TIROS Operational Vertical Sounder (TOVS) is a collection of three instruments on board the NOAA Polar Pathfinder satellite series. The three instruments are the High resolution Infrared Radiation Sounder (HIRS), the Microwave Sounding Unit (MSU), and the Stratospheric Sounding Unit (SSU). The TOVS suite of instruments was first launched on board TIROS-N on 13 October 1978. It has since been launched on NOAA satellites 6 through 14. On the newer satellites, the MSU and SSU instruments have been replaced with improved instruments: the AMSU-A and AMSU-B, respectively. The HIRS instrument is a 20 channel scanning radiometer with channels ranging from the visible to thermal infrared. The MSU instrument is a scanning microwave radiometer with four channels in the 50 to 60 GHz microwave region, and the SSU instrument was not used in the data archived at NSIDC.

The TOVS suite of instruments provides vital measurements for weather forecasting, supplying users with information on the vertical distribution of temperature and moisture in the global atmosphere. TOVS has been particularly useful in providing atmospheric soundings over regions where in situ measurements are sparse.

NSIDC archives and distributes daily and monthly, 100 km resolution data files in HDF format from the TOVS experiments. Please see the NOAA/NASA Polar Pathfinder Data Web site to order data and to obtain guide documentation.

Sample Image

TOVS Sample Image

Atmospheric Temperature (K) at the 850 mb pressure level for the Arctic on 10 April 1996 from TOVS thermal infrared imagery.