Abstract: The intent of the MOPITT ATBD is to describe the algorithm involved in
converting the Level 1 MOPITT radiances into the Level 2 products of retrieved
CO profiles and column amounts of CO and CH 4.

MOPITT CO measurements primary objective is to obtain profiles with a
resolution of 22 km horizontally, 3 km vertically and with an accuracy of 10%
throughout the troposphere. A CO total column amount ... measurement will also be
made with a 10% accuracy. For CH 4 , the objective is to measure the column in
the troposphere to a precision of better than 1%, with a spatial resolution
similar to that of the CO measurement. The column amounts of CO and CH 4 will
only be available on the sunlit side of the orbit as standard level 2 MOPITT
products.

The concentration of CO in the earth's atmosphere had been increasing mainly
because of increased human activities (Khalil and Rasmussen, 1984). However
recent surface mesurments by Novelli et al.(1994), show a leveling off of the
CO concentration. The full range of the effects of the increased concentration
of CO is not fully understood at the present time, but it is believed that CO
is photochemically active and plays a major part in the concentration of OH
radicals in the troposphere. Increased CO may deplete tropospheric OH radicals,
thereby reducing the yearly removal of many natural and anthropogenic trace
species. In particular, this effect may add to the increase of CH 4, which in
turn could further reduce OH concentration. Increased CO may also indirectly
intensify global warming and perturb the stratospheric ozone layer by
increasing the lifetime of trace gases such as CH 4 , CH3 Cl, CH3 CCl3 , and
CFCs.

[Summary adapted from the MOPITT ATBD pdf file.]