Abstract Number: 98 Working Group: Aerosols, Clouds, and Climate
Abstract The aerosol indirect effects on clouds are a major source of uncertainty in climate models and predictions. Among the reasons for the large uncertainty are the complexity of understanding cloud microphysics and the controls on precipitation. Further, cloud measurements are typically difficult and costly, and, as a consequence, uncommon.
Environment Canada has conducted over 30 years of in-cloud aircraft measurements using a National Research Council of Canada Convair 580 and DHC-6 Twin Otter. Measurements of aerosol size distributions, cloud droplets and precipitation-sized particles were made along with measurement of the meteorological data along the flight path. We are using this dataset to investigate the links between aerosol, clouds and precipitation. With this purpose in mind, we are building a database of all the clouds measured during these 30 years. We compare the clouds based on their liquid water content, depth, droplet number concentration, aerosol size distribution at the base, precipitation size distribution, etc.
We start by studying one of the campaigns that took place in the Canadian Atlantic area, measured with the Convair 580: Canadian-SOLAS 2003. All the clouds during this campaign were stratiform warm clouds, most of which were measured over water. Clouds from other campaigns will gradually be added to the database, including over-land clouds and ice clouds. At this conference, we will present our latest results from the analysis of this database.