The second Polar Ozone and Aerosol Measurement instrument (FOAM II) is
a spaceborne experiment designed to measure the vertical profiles of
ozone, water vapor, nitrogen dioxide, aerosol extinction, and temperat
ure in the polar stratosphere and upper troposphere with a vertical re
solution of about 1 km. Measurements are made by the solar occultation
technique. The instrument package, which has a mass of less than 25 k
g, is carried on the Satellite Pour l'Observation de la Terre (SPOT) 3
spacecraft and has a design lifetime of 3-5 years. FOAM II has provid
ed data on the south polar ozone hole, north and south polar ozone phe
nomena, the spatial and temporal variability of stratospheric aerosols
and polar stratospheric clouds, and has detected polar mesospheric cl
ouds.