PROGRAM TITLE:	Total Ozone Mapping Spectrometer (TOMS)
ACTIVITY STREAM:	Data and Observations
SCIENCE ELEMENT:	Climate and Hydrologic Systems
				Global Observing Systems


SCIENTIFIC MERIT:  The TOMS Program goal is to monitor the 
seasonal and long term variations in the stratospheric ozone 
concentration of the Earth, and provide the basic input to 
atmospheric chemistry and dynamics models.  The Nimbus 7 
spacecraft monitored ozone continuously from it's launch in 1978 
until its failure in May, 1993.  A TOMS instrument is currently flying 
on a Russian Meteor 3 spacecraft, and has provided a nearly 
continuos set of measurements since August, 1991.  In May, 1994 an 
Earth Probes TOMS instrument will be launched to continue the 
critical ozone trend measurements from space.  Complementing data 
from the TOMS instruments are the SBUV-2 (Solar Backscatter 
Ultraviolet) measurements. These data provide less frequent maps of 
ozone concentration than TOMS, but can be used to more closely 
examine vertical distribution of ozone.  Operational SBUV-2 
instruments fly on the NOAA platforms.  NOAA 11 was launched in 
September, 1988.  NOAA 13 was launched in August, 1993 and the 
SBUV-2 instrument should become operational in September, 1993.  
The Shuttle Solar Backscattered Ultraviolet (SSBUV) instrument flies 
at regular intervals on the Space Shuttle.  It makes very precise 
measurements of the atmosphere and is used to calibrate the other 
UV instruments in orbit.  Rough ozone measurements from the TOMS 
instruments are reduced in near real time, and made available to the 
scientific community via electronic network.  Precision ozone trend 
data are produced some time later when calibration and ancillary 
data are validated.
STAKEHOLDERS:  The NASA ozone program is conducted in close 
association with researchers at NOAA and the USEPA.
POLICY RELEVANCE:	Stratospheric Ozone and UV-B Radiation
TOMS ozone measurements have played a key role in providing 
information to decision makers regarding the International Ozone 
Assessments and the Montreal Protocol as well as the later revisions.  
PROGRAM CONTACT:	Mr. Stanley Schneider
Chief, Mission Operations and Data Analysis Branch
NASA Headquarters, Code YD
Washington, DC  20546