Ice nucleating particles over the Eastern Mediterranean measured by unmanned aircraft systems
Jann Schrod1, Daniel Weber1, Jaqueline Drücke1, Christos Keleshis2, Micheal Pikridas2, Martin Ebert3, Bojan Cvetkovic4, Slobodan Nickovic4, Eleni Marinou5,6, Holger Baars7, Mihalis Vrekoussis2,8,9, Nikos Mihalopulos2,10, Jean Sciare2, Joachim Curtius1, and Heinz G. Bingemer11Institute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany 2Energy, Environment and Water Research Center, The Cyprus Institute, Nicosia, 2121 Aglantzia, Cyprus 3Institute for Applied Geosciences, Technical University of Darmstadt, 64287 Darmstadt, Germany 4Republic Hydrometeorological Service of Serbia, 11000 Belgrade, Serbia 5Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens, 15236 Athens, Greece 6Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece 7Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany 8Institute of Environmental Physics and Remote Sensing - IUP, University of Bremen, 28359 Bremen, Germany 9Center of Marine Environmental Sciences - MARUM, University of Bremen, 28359 Bremen, Germany 10Institute for Environmental Research and Sustainable Development, National Observatory of Athens, 15236 Athens, Greece
Received: 05 Dec 2016 – Accepted for review: 06 Dec 2016 – Discussion started: 07 Dec 2016
Abstract. During an intensive field campaign on aerosol, clouds and ice nucleation in the Eastern Mediterranean in April 2016, we have measured the abundance of ice nucleating particles (INP) in the lower troposphere from unmanned aircraft systems (UAS). Aerosol samples were collected by miniaturized electrostatic precipitators onboard the UAS at altitudes up to 2.5 km. The number of INP in these samples, which are active in the deposition and condensation modes at temperatures from −20 to −30 °C, were analyzed immediately after collection on site using the ice nucleus counter FRIDGE. During the one month campaign we encountered a series of Saharan dust plumes that traveled at several kilometers altitude. Here we present INP data from 42 individual flights, together with aerosol number concentrations, observations of lidar backscattering, dust concentrations derived by the dust transport model DREAM (Dust Regional Atmospheric Model), and results from scanning electron microscopy. The effect of the dust plumes is reflected by the coincidence of INP with the particulate mass (PM), the lidar signal and with the predicted dust mass of the model. This suggests that mineral dust or a constituent related to dust was a major contributor to the ice nucleating properties of the aerosol. Peak concentrations of above 100 INP std. l−1 were measured at −30 °C. The INP concentration in elevated plumes was on average a factor of 10 higher than at ground level. Since desert dust is transported for long distances over wide areas of the globe predominantly at several km altitude we conclude that INP measurements at ground level may be of limited significance for the situation at the level of cloud formation.
Schrod, J., Weber, D., Drücke, J., Keleshis, C., Pikridas, M., Ebert, M., Cvetkovic, B., Nickovic, S., Marinou, E., Baars, H., Vrekoussis, M., Mihalopulos, N., Sciare, J., Curtius, J., and Bingemer, H. G.: Ice nucleating particles over the Eastern Mediterranean measured by unmanned aircraft systems, Atmos. Chem. Phys. Discuss., doi:10.5194/acp-2016-1098, in review, 2016.