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ACTRIS IMP – ÚČAST ČESKÉ REPUBLIKY V NÁRODNÍCH VÝZKUMNÝCH INFRASTRUKTURÁCH A TÉMATICKÝCH CENTRECH ACTRIS
Ondráček, Jakub ; Váňa, M. ; Klánová, J. ; Holoubek, Ivan ; Ždímal, V.
ACTRIS (The Aerosol, Clouds and Trace Gases Research Infrastructure) je panevropskou výzkumnou infrastrukturou, jejímž hlavním cílem je tvorba vysoce kvalitních dat a podávání informací o krátkodobých složkách atmosféry a o procesech vedoucích ke změnám těchto složek v přírodním a kontrolovaném laboratorním prostředí. ACTRIS je dlouhodobou aktivitou (již od roku 2012, viz. Obr. 1) více než 100 partnerských organizací po celé Evropě, jejichž cílem je integrace, harmonizace a distribuce vysoce kvalitních vědeckých výstupů poskytovaných nejlepšími pracovišti atmosférického výzkumu v (prozatím) 22 evropských zemích. ACTRIS je logickým pokračováním 15-tiletého rozvoje velkých výzkumných infrastruktur financovaného členskými státy a evropskou komisí (EC) prostřednictvím programu výzkumných infrastruktur (Research Infrastructure programme) zahrnujících např. Projekty EARLINET, EUSAAR, CREATE a CLOUDNET.
ACTRIS - Contribution of the Czech Republic: National and Central Facilities.
Ondráček, Jakub ; Holubová, Adéla ; Komínková, Kateřina ; Vítková, Gabriela ; Schwarz, Jaroslav ; Klánová, J. ; Holoubek, Ivan ; Váňa, M. ; Ždímal, Vladimír
ACTRIS (Aerosols, Clouds and Trace gases Research Infrastructure) is an initiative gathering partners all over Europe concentrating on high-quality observations of different atmospheric processes. ACTRIS aims to provide high quality open access data of aerosols, clouds and trace gases and to create a platform for researchers to combine their efforts in resolving the most important environmental challenges (such as air quality, health, climate change, etc.). It is a logical continuation of 15 years of development funded by both Member States and the European Commission through the Research Infrastructure programme (including EARLINET, EUSAAR, CREATE and Cloudnet). ACTRIS has become an important pan-European research infrastructure in 2016 by being accepted into ESFRI (The European Strategy Forum on Research Infrastructure) Roadmap. Currently the ACTRIS is in the phase of becoming pan-European research infrastructure with its own legal entity and operational structure, being supported by two EU projects (ACTRIS-2 and ACTRIS PPP – Preparatory Phase Project).
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Response of aerosol concentrations to the daily atmospheric boundary layer variability at the national atmospheric observatory Košetice
Holubová Šmejkalová, Adéla ; Zíková, Naděžda ; Ždímal, Vladimír ; Komínková, Kateřina ; Holoubek, Ivan
The atmospheric boundary layer (ABL) is the part of the troposphere directly influenced by the properties of the Earth’s surface. The ABL thickness reaches from hundreds of meters to a few kilometres. The daily cycle of the ABL height is primarily result of interaction between incoming solar radiation and Earth’s surface heat fluxes because a turbulent motion is dominant in this layer. Air pollutants are generally emitted from surface and their measured concentrations are also influenced by dilution of the atmosphere, or ABL thickness. This study is focused on the linkage between the diurnal ABL height evolution and aerosol particle number concentrations.
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Characterization of equivalent black carbon (ebc) at a regional backgound site in Central Europe: Variability and source identification
Mbengue, Saliou ; Šerfözö, Norbert ; Holubová Šmejkalová, Adéla ; Holoubek, Ivan
Black carbon (BC) is recognized to play an important role on adverse public health and in the Earth’s climate system (Bond et al., 2013). It is the most efficient light-absorbing aerosol species in the visible spectrum emitted as primary pollutant from a variety of combustion related sources. Although measurements of Equivalent Black Carbon (EBC) with multiple wavelength aethalometer have been used to provide insights regarding the influence of fossil fuel (traffic emissions) and wood smoke in ambient air (Sandradewi et al., 2008, Vaishya et al 2017), scarce studies have been reported in Eastern Central Europe using real-time EBC measurements.\nThis study focuses on the seasonal, diurnal and weekly trends of EBC at a regional background site in Central Europe during a 5-year measurement. Our aim is to identify the potential sources of EBC, especially the influence from fossil fuel and biomass burning.
Utilization of sampling filters from the Kresin atmospheric station for further analysis
Vítková, Gabriela ; Kahoun, D. ; Strnadová, G. ; Hanuš, Vlastimil ; Petrov, M. ; Tříska, Jan ; Holoubek, Ivan
The Kresin At Pacov Atmospheric Station serves as a monitoring point for the occurrence and remote transmission of greenhouse gases, selected atmospheric pollutants and basic meteorological characteristics. The determination of the GHG concentration (CO2, CH4, N2O, CO) is carried out in air continuously sampled at 10, 50, 125 and 250 m heights. The analysis itself takes place at the foot of a high mast where the air is drawn through the tubes of Synflex 1300. lines and individual analyzers are protected from mechanical pollution by input filters that are changed at regular intervals as part of the routine maintenance of the device or earlier when unexpected clogging occurs. Analyzing these filters can provide additional information about the surrounding area. These are stainless filters (Swagelog „T“ filter) with a porosity of 40 μm. A sampling head is provided in front of them to protect them from rough dirt and water drops. The volume flow of the scrubbed air is about 15 l / min, the exchange interval is usually 3 months. The need to replace these filters has increased in recent months as the flow rate on the sampling lines has fallen. The question arises as to how long the filters remain fully passable and how well they serve their purpose without burdening the sampling system and lowering the measurement quality. The results of analyzes of polycyclic aromatic hydrocarbons (PAHs) carried out on filters at the Institute of Chemistry and Biochemistry of the Faculty of Science of South Bohemian University as well as images from the Scanning Electron Microscope (SEM) could be helpful in answering this question. On the basis of the preliminary results, we propose a more extensive study for the use of this waste material for the analysis of solid particles from the atmosphere in the surroundings of AS Křešín near Pacov and the optimization of the QA / QC sampling systems of greenhouse gas analyzers.
Use of the ceilometer data to explainig changes in pollutants concetration gradient in the air during the day
Komínková, Kateřina ; Holoubek, Ivan
For the interpretation of air pollutants concentrations, the one of the key parameter is the atmospheric boundary layer (ABL) evolution during a day and night. The ABL is a broad concept that includes different states of airflow dynamics in the part of troposphere closest to the Earth's surface (0-2 km above the surface), which has an effect in this area. A lot of air flow changes occur in the ABL during the day. For the measurement of substances concentrations in the air the development of mixing layer (ML) in the light part of the day is very important. A lot of ground remote sensing methods was developed for determination of ABL height during the day, one of them which can be very simply operated is to use data from ceilometer. However, the obtained outputs cannot be directly interpreted. In addition, in the case of the terrain measurements a lot of cases when ABL height values cannot be determined because the ceilometer measurement is disturbed can occur.\n\n
Seasonal, weekly and diurnal variability of elemental and organic carbon at a rural background site in Central Europe, a four years of measurement
Mbengue, Saliou ; Fusek, M. ; Schwarz, Jaroslav ; Vodička, Petr ; Holubová, Adéla ; Holoubek, Ivan
Atmospheric organic (OC) and elemental (EC) carbon play an important role in\natmospheric chemistry, climate change and public health. There have been relatively\nfew studies dealing with EC and OC in rural background sites which are less influenced\nby urban and industrial emissions. Nevertheless, measurements at background areas are\nimportant for understanding the transport and transformation characteristics of\nanthropogenic air pollutants, and their effects on various aspects of regional and global\nenvironment changes. This work is one of the rare studies using a semi-continuous\nmeasurement technique to focus on long-term (4 years) measurements of EC and OC at\nregional background site in Europe. It focuses on the factors or phenomena influencing\nboth diurnal and weekly variability of EC and OC concentrations during various seasons\nat rural background area.
Geochemical, mineralogical and stable isotopes aspects of natural attenuation processes of petroleum hydrocarbons
Topinková, Barbora ; Hrkal, Zbyněk (advisor) ; Holoubek, Ivan (referee) ; Černík, Miroslav (referee)
1 Ústav hydrogeologie, inženýrské geologie a užité geofyziky Přírodovědecké fakulty Univerzity Karlovy Geochemické, mineralogické a izotopické aspekty procesů přirozené atenuace ropných uhlovodíků autoreferát disertační práce Mgr. Barbora Topinková Praha, 2010 2 Lokalita Hněvice leží cca 50 km SZ od Prahy, v blízkosti Roudnice nad Labem. Od r. 1943 se tu nachází velkosklad pohonných hmot, který díky havarijním únikům skladovaných motorových olejů, leteckého benzínu a nafty způsobil ve studovaném území rozsáhlou ekologickou zátěž. Kontaminace lokality má směsný charakter a kromě BTEX je tvořena směsí dalších aromatických uhlovodíků, především trimethylbenzenem a ethyltoluenem. Kontaminační mrak o rozloze cca 0,7 km2 je vázán na kvartérní štěrkopískový kolektor a koncentrace ropných uhlovodíků zde dosahuje až 9 mg/l a 8 800mg/kg. Vzhledem k povaze kontaminantu (LNAPL's) se nejvýznamnější podíl znečištění nachází ve svrchní části kolektoru při hladině podzemní vody a cca 2 m pod ní a směrem k bázi kolektoru klesá koncentrace ropných uhlovodíků až k pozaďovým hodnotám. Zájmová část lokality Hněvice studovaná v rámci této disertační práce a mezinárodního projektu CORONA byla vzhledem k ostatním podobným studiím provedeným na jiných lokalitách ve světě (např. Beminji, Vejen, Banisveld) netypicky umístěna na...
Monitoring the coefficient of light scattering on aerosol particles at the Kosetice background station
Holubová Šmejkalová, Adéla ; Zíková, Naděžda ; Ždímal, Vladimír ; Holoubek, Ivan
The direct effect of the atmospheric aerosols to radiation balance is the scattering or absorption of light on these particles. While solar radiation on aerosol particles or clouds negatively affects the radiation (resulting in cooling), absorbtion causes increasing of the ambient air temperature. Contribution to the study of the effect of aerosol particles on the climate, a measurement of the coefficient of light scattering is carry out at the Kosetice background station. The Integrating Nefelometer measures at 3-wavelength (RGB) forward and back light scattering. The values of the scattering coefficient at 550 nm (green) are typically high in the cold part of the year, reflecting both increased concentrations of pollutants and stable atmospheric conditions. Daily variability is the smallest in summer (varies between 25 and 18 Mm-1), the most noticeable daily variation is observed in the spring, when stable values 44 Mm-1 drop after noon to 26 Mm-1. The calculation of Ångström's exponent showed that in the summer, the fine fraction dominates in the sampled air.
Highly time resolved measurement of atmospheric elemental and organic carbon at a typical background site in Central Europe.
Mbengue, Saliou ; Fusek, M. ; Schwarz, Jaroslav ; Holoubek, Ivan
Atmospheric organic (OC) and elemental (EC) carbon play an important role in atmospheric chemistry, climate change and public health. There have been relatively few studies dealing with EC and OC in rural background sites which are less influenced by urban and industrial emissions. Nevertheless, measurements at background areas are important for understanding the transport and transformation characteristics of anthropogenic air pollutants, and their effects on various aspects of regional and global environment changes. In this study, we focus on variability of EC and OC concentrations (considering various day categories and seasons) from a rural background site which is representative for Central European rural areas.\n

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