ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-9881-2012 Aircraft measurements of wave clouds Cui Z. 1 Blyth A. M. 1 2 Bower K. N. 3 Crosier J. 2 3 Choularton T. 3 Institute for Climate and Atmospheric Science, School of Earth and Environment, University of Leeds, UK National Centre for Atmospheric Science, UK Centre for Atmospheric Science, SEAES, University of Manchester, UK 29 10 2012 12 20 9881 9892 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.net/12/9881/2012/acp-12-9881-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/9881/2012/acp-12-9881-2012.pdf

In this paper, aircraft measurements are presented of liquid phase (ice-free) wave clouds made at temperatures greater than −5°C that formed over Scotland, UK. The horizontal variations of the vertical velocity across wave clouds display a distinct pattern. The maximum updraughts occur at the upshear flanks of the clouds and the strong downdraughts at the downshear flanks. The cloud droplet concentrations were a couple of hundreds per cubic centimetres, and the drops generally had a mean diameter between 15–45 μm. A small proportion of the drops were drizzle. The measurements presented here and in previous recent studies suggest a different interaction of dynamics and microphysics in wave clouds from the accepted model. The results in this paper provide a case for future numerical simulation of wave cloud and the interaction between wave and cloud.