2016, Engelmann, Ronny, Kanitz, Thomas, Baars, Holger, Heese, Birgit, Althausen, Dietrich, Skupin, Annett, Wandinger, Ulla, Komppula, Mika, Stachlewska, Iwona S., Amiridis, Vassilis, Marinou, Eleni, Mattis, Ina, Linné, Holger, Ansmann, Albert

The atmospheric science community demands autonomous and quality-assured vertically resolved measurements of aerosol and cloud properties. For this purpose, a portable lidar called Polly was developed at TROPOS in 2003. The lidar system was continuously improved with gained experience from the EARLINET community, involvement in worldwide field campaigns, and international institute collaborations within the last 10 years. Here we present recent changes of the setup of the portable multiwavelength Raman and polarization lidar PollyXT and discuss the improved capabilities of the system by means of a case study. The latest system developments include an additional near-range receiver unit for Raman measurements of the backscatter and extinction coefficient down to 120 m above ground, a water-vapor channel, and channels for simultaneous measurements of the particle linear depolarization ratio at 355 and 532 nm. Quality improvements were achieved by systematically following the EARLINET guidelines and the international PollyNET quality assurance developments. A modified ship radar ensures measurements in agreement with air-traffic safety regulations and allows for 24∕7 monitoring of the atmospheric state with PollyXT.

2016, Baars, Holger, Kanitz, Thomas, Engelmann, Ronny, Althausen, Dietrich, Heese, Birgit, Komppula, Mika, Preißler, Jana, Tesche, Matthias, Ansmann, Albert, Wandinger, Ulla, Lim, Jae-Hyun, Ahn, Joon Young, Stachlewska, Iwona S., Amiridis, Vassilis, Marinou, Eleni, Seifert, Patric, Hofer, Julian, Skupin, Annett, Schneider, Florian, Bohlmann, Stephanie, Foth, Andreas, Bley, Sebastian, Pfüller, Anne, Giannakaki, Eleni, Lihavainen, Heikki, Viisanen, Yrjö, Hooda, Rakesh Kumar, Pereira, Sérgio Nepomuceno, Bortol, Daniele, Wagner, Frank, Mattis, Ina, Janicka, Lucja, Markowicz, Krzysztof M., Achtert, Peggy, Artaxo, Paulo, Pauliquevis, Theotonio, Souza, Rodrigo A.F., Sharma, Ved Prakesh, van Zyl, Pieter Gideon, Beukes, Johan Paul, Sun, Junying, Rohwer, Erich G., Deng, Ruru, Mamouri, Rodanthi-Elisavet, Zamorano, Felix

A global vertically resolved aerosol data set covering more than 10 years of observations at more than 20 measurement sites distributed from 63° N to 52° S and 72° W to 124° E has been achieved within the Raman and polarization lidar network PollyNET. This network consists of portable, remote-controlled multiwavelength-polarization-Raman lidars (Polly) for automated and continuous 24/7 observations of clouds and aerosols. PollyNET is an independent, voluntary, and scientific network. All Polly lidars feature a standardized instrument design with different capabilities ranging from single wavelength to multiwavelength systems, and now apply unified calibration, quality control, and data analysis. The observations are processed in near-real time without manual intervention, and are presented online at http://polly.tropos.de/. The paper gives an overview of the observations on four continents and two research vessels obtained with eight Polly systems. The specific aerosol types at these locations (mineral dust, smoke, dust-smoke and other dusty mixtures, urban haze, and volcanic ash) are identified by their Ångström exponent, lidar ratio, and depolarization ratio. The vertical aerosol distribution at the PollyNET locations is discussed on the basis of more than 55 000 automatically retrieved 30 min particle backscatter coefficient profiles at 532 nm as this operating wavelength is available for all Polly lidar systems. A seasonal analysis of measurements at selected sites revealed typical and extraordinary aerosol conditions as well as seasonal differences. These studies show the potential of PollyNET to support the establishment of a global aerosol climatology that covers the entire troposphere.

2017, Engelmann, Ronny, Ansmann, Albert, Horn, Stefan, Seifert, Patric, Althausen, Dietrich, Tesche, Matthias, Esselborn, Michael, Fruntke, Julia, Lieke, Kirsten, Freudenthaler, Volker, Gross, Silke

A wind Doppler lidar was deployed next to three aerosol lidars during the SAMUM–2 campaign on the main island of Cape Verde. The effects of the differential heating of the island and the surrounding ocean and the orographic impact of the capital island Santiago and the small island on its luv side, Maio, are investigated. Horizontal and vertical winds were measured in the disturbed maritime boundary layer and compared to local radiosoundings. Lidar measurements from the research aircraft Falcon and a 3-D Large Eddy Simulation (LES) model were used in addition to study the heating effects on the scale of the islands. Indications are found that these effects can widely control the downward mixing from greater heights to the surface of African aerosols, mainly Saharan dust and biomass-burning smoke, which were detected in a complex layering over the Cape Verde region.