Atmospheric Measurement Techniques Discussions www.atmos-meas-tech-discuss.net 1867-8610 2 3 2009 10.5194/amtd-2-1487-2009 http://www.atmos-meas-tech-discuss.net/2/1487/2009/ http://www.atmos-meas-tech-discuss.net/2/1487/2009/amtd-2-1487-2009.html http://www.atmos-meas-tech-discuss.net/2/1487/2009/amtd-2-1487-2009.pdf 1487 1536 2009-06-24 Airborne lidar reflectance measurements at 1.57 μm in support of the A-SCOPE mission for atmospheric CO₂ A. Amediek axel.amediek@dlr.de A. Fix G. Ehret J. Caron Y. Durand Deutsches Zentrum für Luft- und Raumfahrt (DLR) Oberpfaffenhofen, Institut für Physik der Atmosphäre, 82234 Wessling, Germany ESA/ESTEC, Earth Observation Project Department, 2201 AZ Noordwijk, The Netherlands working as a contractor from RHEA System SA The characteristics of the lidar reflectance of the Earth's surface is an important issue for the IPDA lidar technique (integrated path differential absorption lidar) which is the proposed method for the spaceborne measurement of atmospheric carbon dioxide within the framework of ESA's A-SCOPE project. Both, the absolute reflectance of the ground and its variations have an impact on the measurement sensitivity. The first aspect influences the instrument's signal to noise ratio, the second one can lead to retrieval errors, if the ground reflectance changes are strong on small scales. The investigation of the latter is the main purpose of this study. 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