Aerosols are an important factor of the Earth climatic system and they play a key
role for air quality and public health. Observations of the Oxygen A-Band at 760
nm can provide information on the vertical distribution of aerosols from passive
sensors, that can be of great interest for operational monitoring applications with
high spatial coverage if the aerosol information is obtained with sufficient precision,
accuracy and vertical resolution. To address this issue, retrieval simulations of the
aerosol vertical profile retrieval from Oxygen A-Band observations by GOSAT and OCO-2, the upcoming Sentinel 5-P mission and the proposed (and unfortunately now dropped) CarbonSat mission have been carried out.

In this wide ranging talk I will discuss the role of aerosols in the atmosphere and the challenges faced when measuring them, before presenting several examples of the simulations to allow us to better understand the impact of instrument design on performance in the Oxygen A-Band.