Helicopter-borne observations of atmospheric clouds, aerosol, and dynamics over the Azores - the ACORES campaign.

Description of ACTOS data ACORES campaign 2017 Introduction In July 2027, the helicopter-borne measurement platform ACTOS (Airborne Cloud Turbulence Observation System, Siebert et al., 2006) was deployed over the island of Graciosa (Azores) to investigate the interaction of clouds, aerosol particles and atmospheric dynamics under the influence of different air masses. This document describes selected parameters of the data set that enable each user to gain an initial impression of the measurement situation and perform basic data analyses. The data is stored here with the native temporal resolution of 100 Hz. With a typical flight speed of 20 m/s, this means that the spatial resolution is typically 20 cm. Turbulence data with even higher resolution is available for individual flights, but this requires individual post-processing and is available on request and within the framework of cooperation agreements. The same applies in part to cloud droplet, aerosol particle, and other data as mentioned in Siebert et al., (2021) Contact All data and more detailed information are available from the author: [e-mail] Location All flights have been operated around the airport of Graciosa with the coordinates 39° 5’ 32” N and 028° 1’ 47” W about 26 m above mean sea level; the maximum distance to the airport was about 20 nautical miles and the maximum height was 10.000 feet (about 3000 m). Parameter Paramter name Description Unit Measurement Device Date/Time Date and Time UTC GPS zb Barometric height m Pressure device pp Static pressure hPa Pressure device TT Static temperature °C PT-100 PT Potential temperature K PT-100 / Pressure device T_UFT (Fast) temperature °C Ultrafast thermometer PVM_LWC Liquid water content g / m3 PVM-100A PVM_PSA Particle surface area cm2 / m3 “” PVM_Reff Effective radius micron “” CDP_Reff Effective radius micron CDP-2 CDP_LWC Liquid water content g / m3 “” CDP_N Droplet number concentration # / cm3 “” DP_a absolute humidity g / m3 Dewpoint mirror DP_TD Dewpoint temperature °C “” DP_TT Static temperature °C “” UU Horizontal wind speed m / s Ultrasonic anemometer & inertial navigation unit DD Wind direction ° “” wHP Fluctuations of vertical wind m / s “” a_LI absolute humidity g / m3 Open Path infrared hygrometer N_F1 fast aerosol particle concentration # / cm3 MCPC N_TSI slow aerosol particle concentration # / cm3 TSI CPC Lat Latitude rad GPS Lon Longitude rad “ All devices are explained in the given references Literature H. Siebert, H. Franke, K. Lehmann, R. Maser, E. W. Saw, D. Schell, R. A. Shaw, and M. Wendisch: Probing fine-scale dynamics and microphysics of clouds with helicopter-borne measurements. Bull. Am.Meteor. Soc., 87:1727 – 1738, 2006. H. Siebert, K. E. Szodry, U. Egerer, B. Wehner, K. C. S. Henning, J. Lückerath, O. Welz, K. Weinhold, F. Lauermann, M. Gottschalk, A. Ehrlich, M. Wendisch, P. Fialho, S. Viviani, G. Roberts, S. Schum, R. A. Shaw, C. Mazzoleni, J. Nowak, S. Malinowski, K. Karpinska, W. Kumala, and D. Czyzewska: Observations of aerosol, cloud, turbulence, and radiation properties at the top of the marine boundary layer over the Eastern North Atlantic Ocean: The ACORES campaign. Bull. Amer. Meteor. Soc., pages E123 – E147, 2021.