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- ItemAerosol properties over Southeastern China from multi-wavelength Raman and depolarization lidar measurements(Les Ulis : EDP Sciences, 2016) Heese, Birgit; Althausen, Dietrich; Baars, Holger; Bohlmann, Stephanie; Deng, RuruA dataset of particle optical properties of highly polluted urban aerosol over the Pearl River Delta, Guangzhou, China is presented. The data were derived from multi-wavelengths Raman and depolarization lidar PollyXT and AERONET sun photometer measurements. The measurement campaign was conducted from Nov 2011 to June 2012. High aerosol optical depth was observed in the polluted atmosphere over this megacity, with a mean value of 0.54 ± 0.33 and a peak value of even 1.9. For the particle characterization the lidar ratio and the linear particle depolarization ratio, both at 532 nm, were used. The mean values of these properties are 48.0 sr ± 10.7 sr for the lidar ratio and 4%+-4% for the particle depolarization ratio, which means most depolarization measurements stayed below 10%. So far, most of these results indicate urban pollution particles mixed with particles arisen from biomass and industrial burning.
- Item3D Structure of Saharan Dust Transport Towards Europe as Seen by CALIPSO(Les Ulis : EDP Sciences, 2016) Marinou, Eleni; Amiridis, Vassilis; Tsekeri, Alexandra; Solomos, Stavros; Kokkalis, Panos; Proestakis, Emmanouil; Kottas, Michael; Binietoglou, Ioannis; Zanis, Prodromos; Kazadzis, Stelios; Wandinger, Ulla; Ansmann, AlbertWe present a 3D multi-year monthly mean climatology of Saharan dust advection over Europe using an area-optimized pure dust CALIPSO product. The product has been developed by applying EARLINET-measured dust lidar ratios and depolarization-based dust discrimination methods and it is shown to have a very good agreement in terms of AOD when compared to AERONET over Europe/North Africa and MODIS over Mediterranean. The processing of such purely observational data reveals the certain seasonal patterns of dust transportation towards Europe and the Atlantic Ocean. The physical and optical properties of the dust layer are identified for several areas near the Saharan sources, over the Mediterranean and over continental Europe.
- ItemData Science: History repeated? – The heritage of the Free and Open Source GIS community(München : European Geosciences Union, 2014) Löwe, Peter; Neteler, Markus[no abstract available]
- ItemFree tropospheric aerosols over South Africa(Les Ulis : EDP Sciences, 2016) Elina, Giannakaki; Pfüller, Anne; Korhonen, Kimmo; Mielonen, Tero; Laakso, Lauri; Vakkari, Ville; Baars, Holger; Engelmann, Ronny; Beukes, Johan P.; Van Zyl, Pieter G.; Josipovic, Miroslav; Tiitta, Petri; Chiloane, Kgaugelo; Piketh, Stuart; Lihavainen, Heikki; Lehtinen, KariRaman lidar data of one year was been analyzed to obtain information relating aerosol layers in the free troposphere over South Africa, Elandsfontein. In total, 375 layers were observed above the boundary layer during the period 30th January 2010 – 31st January 2011. The seasonal behavior of aerosol layer geometrical characteristics as well as intensive and extensive optical properties were studied. In general, layers were observed at higher altitudes during spring (2520 ± 970 m) while the geometrical layer depth did not show any significant seasonal dependence. The variations of most of the intensive and extensive optical properties analyzed were high during all seasons. Layers were observed at mean altitude of 2100 m ± 1000 m with lidar ratio at 355 nm of 67 ± 25 and extinction-related Ångström exponent between 355 and 532 nm of 1.9 ± 0.8.
- ItemGlobal-scale atmosphere monitoring by in-service aircraft – current achievements and future prospects of the European Research Infrastructure IAGOS(Milton Park : Taylor & Francis, 2015) Petzold, Andreas; Thouret, Valerie; Gerbig, Christoph; Zahn, Andreas; Brenninkmeijer, Carl A.M.; Gallagher, Martin; Hermann, Markus; Pontaud, Marc; Ziereis, Helmut; Boulanger, Damien; Marshall, Julia; Nédélec, Philippe; Smit, Herman G.J.; Friess, Udo; Flaud, Jean-Marie; Wahner, Andreas; Cammas, Jean-Pierre; Volz-Thomas, AndreasThe European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System) operates a global-scale monitoring system for atmospheric trace gases, aerosols and clouds utilising the existing global civil aircraft. This new monitoring infrastructure builds on the heritage of the former research projects MOZAIC (Measurement of Ozone and Water Vapour on Airbus In-service Aircraft) and CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container). CARIBIC continues within IAGOS and acts as an important airborne measurement reference standard within the wider IAGOS fleet. IAGOS is a major contributor to the in-situ component of the Copernicus Atmosphere Monitoring Service (CAMS), the successor to the Global Monitoring for the Environment and Security – Atmospheric Service, and is providing data for users in science, weather services and atmospherically relevant policy. IAGOS is unique in collecting regular in-situ observations of reactive gases, greenhouse gases and aerosol concentrations in the upper troposphere and lowermost stratosphere (UTLS) at high spatial resolution. It also provides routine vertical profiles of these species in the troposphere over continental sites or regions, many of which are undersampled by other networks or sampling studies, particularly in Africa, Southeast Asia and South America. In combination with MOZAIC and CARIBIC, IAGOS has provided long-term observations of atmospheric chemical composition in the UTLS since 1994. The longest time series are 20 yr of temperature, H2O and O3, and 9–15 yr of aerosols, CO, NO y , CO2, CH4, N2O, SF6, Hg, acetone, ~30 HFCs and ~20 non-methane hydrocarbons. Among the scientific highlights which have emerged from these data sets are observations of extreme concentrations of O3 and CO over the Pacific basin that have never or rarely been recorded over the Atlantic region for the past 12 yr; detailed information on the temporal and regional distributions of O3, CO, H2O, NO y and aerosol particles in the UTLS, including the impacts of cross-tropopause transport, deep convection and lightning on the distribution of these species; characterisation of ice-supersaturated regions in the UTLS; and finally, improved understanding of the spatial distribution of upper tropospheric humidity including the finding that the UTLS is much more humid than previously assumed.
- ItemNear-range receiver unit of next generation PollyXT used with Koldeway aerosol Raman lidar in Arctic(Les Ulis : EDP Sciences, 2016) Stachlewska, Iwona S.; Markowicz, Krzysztof M.; Ritter, Christoph; Roland Neuber, Roland; Heese, Birgit; Engelmann, Ronny; Linne, HolgerThe Near-range Aerosol Raman lidar (NARLa) receiver unit, that was designed to enhance the detection range of the NeXT generation PollyXT Aerosol-Depolarization-Raman (ADR) lidar of the University of Warsaw, was employed next the Koldeway Aerosol Raman Lidar (KARL) at the AWI-IPEV German-French station in Arctic during Spring 2015. Here we introduce shortly design of both lidars, the scheme of their installation next to each other, and preliminary results of observations aiming at arctic haze investigation by the lidars and the iCAP a set of particle counter and aethalometer installed under a tethered balloon.
- ItemTowards OSGeo best practices for scientific software citation: Integration options for persistent identifiers in OSGeo project repositories(Genf : Zenodo, 2017) Löwe, Peter Heinz; Neteler, Markus; Goebel, Jan; Tullney, MarcoAs a contribution to the currently ongoing larger effort to establish Open Science as best practices in academia, this article focuses on the Open Source and Open Access tiers of the Open Science triad and community software projects. The current situation of research software development and the need to recognize it as a significant contribution to science is introduced in relation to Open Science. The adoption of the Open Science paradigms occurs at different speeds and on different levels within the various fields of science and crosscutting software communities. This is paralleled by the emerging of an underlying futuresafe technical infrastructure based on open standards to enable proper recognition for published articles, data, and software. Currently the number of journal publications about research software remains low in comparison to the amount of research code published on various software repositories in the WWW. Because common standards for the citation of software projects (containers) and versions of software are lacking, the FORCE11 group and the CodeMeta project recommending to establish Persistent Identifiers (PIDs), together with suitable metadata setss to reliably cite research software. This approach is compared to the best practices implemented by the OSGeo Foundation for geospatial community software projects. For GRASS GIS, a OSGeo project and one of the oldest geospatial open source community projects, the external requirements for DOI-based software citation are compared with the projects software documentation standards. Based on this status assessment, application scenarios are derived, how OSGeo projects can approach DOI-based software citation, both as a standalone option and also as a means to foster open access journal publications as part of reproducible Open Science.
- ItemOverview of the Earthcare L2 lidar retrieval chain(Les Ulis : EDP Sciences, 2016) van Zadelhoff, Gerd-Jan; Donovan, D.; Wandinger, U.; Daou, D.; Horn, S.; Hunerbein, A.; Fischer, J.; von Bismarck, J.; Filipitsch, F.; Docter, N.; Eisinger, M.; Lajas, D.; Wehr, T.In this paper an introduction to the planned L2 retrieval algorithms for the Earth Clouds and Radiation Explorer (EarthCARE) lidar ATLID is given. The ATLID instrument is a high spectral resolution lidar which will provide independent retrievals of extinction and backscatter profiles and will be launched in 2018. A short description of the intended operational ESA products is given together with the logic behind the choices made.
- ItemMeasuring soot particles from automotive exhaust emissions(Les Ulis : EDP Sciences, 2014) Andres, Hanspeter; Lüönd, Felix; Schlatter, Jürg; Auderset, Kevin; Jordan-Gerkens, Anke; Nowak, Andreas; Ebert, Volker; Buhr, Egbert; Klein, Tobias; Tuch, Thomas; Wiedensohler, Alfred; Mamakos, Athanasios; Riccobono, Francesco; Discher, Kai; Högström, Richard; Yli-Ojanperä, Jaakko; Quincey, PaulThe European Metrology Research Programme participating countries and the European Union jointly fund a three year project to address the need of the automotive industry for a metrological sound base for exhaust measurements. The collaborative work on particle emissions involves five European National Metrology Institutes, the Tampere University of Technology, the Joint Research Centre for Energy and Transport and the Leibniz Institute for Tropospheric Research. On one hand, a particle number and size standard for soot particles is aimed for. Eventually this will allow the partners to provide accurate and comparable calibrations of measurement instruments for the type approval of Euro 5b and Euro 6 vehicles. Calibration aerosols of combustion particles, silver and graphite proof partially suitable. Yet, a consensus choice together with instrument manufactures is pending as the aerosol choice considerably affects the number concentration measurement. Furthermore, the consortium issued consistent requirements for novel measuring instruments foreseen to replace today’s opacimeters in regulatory periodic emission controls of soot and compared them with European legislative requirements. Four partners are conducting a metrological validation of prototype measurement instruments. The novel instruments base on light scattering, electrical, ionisation chamber and diffusion charging sensors and will be tested at low and high particle concentrations. Results shall allow manufacturers to further improve their instruments to comply with legal requirements.
- ItemHETEAC: The Aerosol Classification model for EarthCARE(Les Ulis : EDP Sciences, 2016) Wandinger, Ulla; Baars, Holger; Engelmann, Ronny; Hünerbein, Anja; Horn, Stefan; Kanitz, Thomas; Donovan, David; van Zadelhoff, Gerd-Jan; Daou, David; Fischer, Jürgen; von Bismarck, Jonas; Filipitsch, Florian; Docter, Nicole; Eisinger, Michael; Lajas, Dulce; Wehr, TobiasWe introduce the Hybrid End-To-End Aerosol Classification (HETEAC) model for the upcoming EarthCARE mission. The model serves as the common baseline for development, evaluation, and implementation of EarthCARE algorithms. It shall ensure the consistency of different aerosol products from the multi-instrument platform as well as facilitate the conform specification of broad-band optical properties necessary for the EarthCARE radiative closure efforts. The hybrid approach ensures the theoretical description of aerosol microphysics consistent with the optical properties of various aerosol types known from observations. The end-to-end model permits the uniform representation of aerosol types in terms of microphysical, optical and radiative properties.