ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-10-3301-2010 A comparison of ship and satellite measurements of cloud properties in the southeast Pacific stratus deck Brunke M. A. 1 de Szoeke S. P. 2 Zuidema P. 3 Zeng X. 1 The University of Arizona, Department of Atmospheric Sciences, Tucson, Arizona, USA Oregon State University, College of Oceanic and Atmospheric Sciences, Corvallis, Oregon, USA University of Miami, Rosentiel School of Marine and Atmospheric Science, Miami, Florida, USA 08 02 2010 10 2 3301 3318 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/10/3301/2010/acpd-10-3301-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/10/3301/2010/acpd-10-3301-2010.pdf

Here, liquid water path (LWP), cloud fraction, cloud top height, and cloud base height are retrieved by a suite of satellite instruments (the CPR aboard CloudSat, CALIOP aboard CALIPSO, and MODIS aboard Aqua) and compared to ship observations from research cruises made in 2001 and 2003–2007 into the stratus/stratocumulus deck over the southeast Pacific Ocean. It is found that CloudSat LWP is generally too high over this region and the CloudSat/CALIPSO cloud bases are too low which is to be expected from the increased sensitivity to precipitation by both the radar and lidar. This results in a relationship (LWP~<i>h</i><sup>9</sup>) between CloudSat LWP and CALIPSO cloud thickness (<i>h</i>) that is very different from the adiabatic relationship (LWP~<i>h</i><sup>2</sup>) from in situ observations. Furthermore, comparing results from a global model (CAM3.1) to ship observations reveals that, while the simulated LWP is quite reasonable, the model cloud is too thick and too low, allowing the model to have LWPs that are almost independent of <i>h</i>. Such differences may be reduced in future versions of both the satellite data and the model.

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