Millimetre-wave limb-sounder on Geophysica

The MARSCHALS instrument in the belly pod of the high-altitude aircraft Geophysica. The instrument sounds the mid and upper troposphere and lower stratosphere in limb geometry to acquire high-resolution vertical profiles of atmospheric gases. During the campaign in northern Australia, it took measurements of water vapour and ozone, and demonstrated full performance in the presence of cirrus cloud. It is currently being upgraded to also observe carbon monoxide and other trace gases relevant for understanding of the chemistry and dynamics of this important atmospheric region. The instrument development was led by Rutherford-Appleton Laboratories in UK. It is a demonstrator for the STEAM-R millimetre-wave limb-sounder, which would be provided by the Swedish National Space Board for flight on the PREMIER satellite.