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1.
Aerosol light extinction coefficient closure : comparison of airborne in-situ measurements with LIDAR measurements during JATAC/CAVA-AW 2021/2022 campaigns
Marija Bervida, Jesús Yus-Díez, Luka Drinovec, Uroš Jagodič, Blaž Žibert, Matevž Lenarčič, Griša Močnik, 2024, published scientific conference contribution abstract

Abstract: The JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands resulted in a large in-situ and remote measurement dataset. Its main objective was the calibration and validation of the ESA satellite Aeolus ALADIN Lidar. The campaign also featured secondary scientific objectives related to climate change. Constraining remote sensing measurements with those provided by in-situ instrumentation is crucial for proper characterization and accurate description of the 3-D structure of the atmosphere.We present the results performed with an instrumented light aircraft (Advantic WT-10) set-up for in-situ aerosol measurements. Twenty-seven flights were conducted over the Atlantic Ocean at altitudes around and above 3000 m above sea level during intense dust transport events. Simultaneous measurements with PollyXT, and eVe ground-based lidars took place, determining the vertical profiles of aerosol optical properties, which were also used to plan the flights.The aerosol light extinction coefficient was obtained at three different wavelengths as a combination of the absorption coefficients determined using Continuous Light Absorption Photometers (CLAP) and the scattering coefficients measured with an Ecotech Aurora 4000 nephelometer, which also measured the backscatter fraction. The particle size distributions above 0.3 µm diameter were measured with two Grimm 11-D Optical Particle Size Spectrometers (OPSS). Moreover, CO2 concentration, temperature, aircraft GPS position and altitude, air and ground speed were also measured.We compare the in-situ aircraft measurements of the aerosol extinction coefficients with the AEOLUS lidar derived extinction coefficients, as well as with the ground-based eVe and PollyXT lidar extinction coefficients when measurements overlapped in space and time. The comparison was performed at the closest available wavelengths, with in-situ measurements inter/extrapolated to those of the lidar systems.In general we find an underestimation of the extinction coefficient obtained by lidars compared to the in-situ extinction coefficient. The slopes of regression lines of ground-based lidars, PollyXT and eVe, against the in-situ measurements are characterised by values ranging from 0.61 to 0.7 and R2 between 0.71 and 0.89. Comparison further suggests better agreement between Aeolus ALADIN lidar and the in-situ measurements. Relationship described by fitting the Aeolus to in-situ data is characterised by the slope value 0.76 and R2 of 0.8.The causes of better agreement of the in-situ measurements with the ALADIN lidar than with the surface based ones are being studied, with several reasons being considered: a) lower spatial and temporal resolution which homogenize the area of study in comparison with the very fine vertical variations of the aerosols, which can be detected with the surface-based measurements, impairing the comparison with highly vertically resolved ground-lidar measurements while not affecting averaged space-borne lidar; b) the effect of lower clouds/ Saharan air layers on the attenuation of the lidar signal.The presented results show the importance of the comparison of the remote with in-situ measurements for the support of the research on evolution, dynamics, and predictability of tropical weather systems and provide input into and verification of the climate models.
Keywords: LIDAR, Aeolus, ALADIN, in-situ measurements, aerosol absorption, aerosol extinction, airborne measurements
Published in RUNG: 18.03.2024; Views: 168; Downloads: 5
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2.
Aerosol dust absorption : measurements with a reference instrument (PTAAM-2[lambda]) and impact on the climate as measured in airborne JATAC/CAVA-AW 2021/2022 campaigns
Jesús Yus-Díez, Luka Drinovec, Marija Bervida, Uroš Jagodič, Blaž Žibert, Griša Močnik, 2024, published scientific conference contribution abstract

Abstract: Aerosol absorption coefficient measurements classically feature a very large uncertainty, especially given the absence of a reference method. The most used approach using filter-photometers is by measuring the attenuation of light through a filter where aerosols are being deposited. This presents several artifacts, with cross-sensitivity to scattering being most important at high single scattering albedo with the error exceeding 100%. We present lab campaign results where we have resuspended dust samples from different mid-latitude desert regions and measured the dust absorption and scattering coefficients, their mass concentration and the particle size distribution. The absorption coefficients were measured with two types of filter photometers: a Continuous Light Absorption Photometers (CLAP) and a multi-wavelength Aethalometer (AE33). The  dual-wavelength photo-thermal interferometer (PTAAM-2λ) was employed as the reference. Scattering coefficients were measured with an Ecotech Aurora 4000 nephelometer. The mass concentration was obtained after the weighting of filters before and after the sampling, and the particle size distribution (PSD) was measured by means of optical particle counters (Grimm 11-D).Measurements of the scattering with the nephelometer and absorption with the PTAAM-2λ we obtained the filter photometer multiple scattering parameter and cross-sensitivity to scattering as a function of the different sample properties. Moreover, by determining the mass concentration and the absorption coefficients of the samples, we derived the mass absorption cross-sections of the different dust samples, which can be linked to their size distribution as well as to their mineralogical composition.The focus of the JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands was on the calibration/validation of the ESA Aeolus satellite ALADIN lidar, however, the campaign also featured secondary scientific climate-change objectives. As part of this campaign, a light aircraft was set-up for in-situ aerosol measurements. Several flights were conducted over the Atlantic Ocean up to and above 3000 m above sea level during intense dust transport events. The aircraft was instrumented to determine the absorption coefficients using a pair of Continuous Light Absorption Photometers (CLAPs) measuring in the fine and coarse fractions separately, with parallel measurements of size distributions in these size fractions using two Grimm 11-D Optical Particle Size Spectrometers (OPSS). In addition, we performed measurements of the total and diffuse solar irradiance with a DeltaT SPN1 pyranometer.The combination of the absorption and PSD with source identification techniques enabled the separation of the contributions to  absorption by dust and black carbon. The atmospheric heating rate of these two contributions was determined by adding the irradiance measurements. Therefore, the integration of the results from the Using laboratory resuspension experiments  to interpret the airborne measurements is of great relevance for the determination  of the radiative effect of the Saharan Aerosol Layer as measured over the tropical Atlantic ocean.
Keywords: black carbon, mineral dust, Saharan dust, atmospheric heating rate, climate change, airborne measurements
Published in RUNG: 18.03.2024; Views: 162; Downloads: 2
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3.
Motivacija zaposlenih in njena povezanost z organizacijsko klimo : diplomsko delo
Marija Kurdumanović, 2024, undergraduate thesis

Abstract: Motivacija zaposlenih ima ključno vlogo pri povečanju produktivnosti, zadovoljstva pri delu in splošnem uspehu organizacije. Tesno je povezana z organizacijsko klimo, ki se nanaša na delovno okolje, kulturo in prakse znotraj organizacije. Namen diplomskega dela je temeljito raziskati odnos med motivacijo zaposlenih in organizacijsko klimo ter izpostaviti ključne dejavnike in njihov vpliv na uspešnost organizacije. Za razumevanje odnosa med motivacijo zaposlenih in organizacijsko klimo je ključnega pomena vstop v ustrezne teoretične okvire. Eden od takih okvirjev je Maslowa hierarhija potreb, ki nakazuje, da posameznikovo motivacijo poganja izpolnjevanje različnih ravni potreb, vključno s fiziološkimi, varnostnimi, socialnimiter spoštovanje in samoaktualizacija. Z razumevanjem teh potreb lahko organizacije ustvarijo podporno klimo, ki spodbuja motivacijo zaposlenih. Organizacijska klima močno vpliva na motivacijo zaposlenih. Pozitivna klima, ki jo zaznamujejo zaupanje, odprti komunikacijski kanali in jasni cilji, povečuje motivacijo zaposlenih. Nasprotno pa lahko negativna klima, za katero so značilni pomanjkanje podpore, hierarhične strukture in omejene možnosti za rast, močno ovira motivacijo zaposlenih. Bistvenega pomena je, da organizacije prepoznajo te vplive in sprejmejo ukrepe za spodbujanje vzdušja, ki spodbuja motivacijo. V tem delu je bila izvedena raziskava o motivaciji zaposlenih in njeni povezanosti z organizacijsko klimo v podjetju, ki je želelo ostati anonimno. V raziskavi je sodelovalo 20 zaposlenih v raziskovalnem podjetju. Organizacijska kultura tega podjetja je dobra, motivacija pa močno vpliva na organizacijsko klimo.
Keywords: diplomske naloge, motivacija, organizacijska klima, zadovoljstvo zaposlenih, dimenzije organizacijske klime
Published in RUNG: 28.02.2024; Views: 225; Downloads: 25
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4.
Airborne in-situ measurements during JATAC/CAVA-AW 2021/2022 campaigns : first climate-relevant results
Jesús Yus-Díez, Marija Bervida, Luka Drinovec, Blaž Žibert, Matevž Lenarčič, Griša Močnik, 2023, published scientific conference contribution abstract

Abstract: The JATAC campaign in September 2021 and September 2022 on and above Cape Verde Islands have resulted in a large dataset of in-situ and remote measurements. In addition to the calibration/validation of the ESA’s Aeolus ALADIN during the campaign, the campaign also featured secondary scientific objectives related to climate change. The atmosphere above the Atlantic Ocean off the coast of West Africa is ideal for the study of the Saharan Aerosol layer (SAL), the long-range transport of dust, and the regional influence of SAL aerosols on the climate. We have instrumented a light aircraft (Advantic WT-10) with instrumentation for the in-situ aerosol characterization. Ten flights were conducted over the Atlantic Ocean up to over 3000 m above sea level during two intense dust transport events. PollyXT, and EvE lidars were deployed at the Ocean Science Center, measuring the vertical optical properties of aerosols and were also used to plan the flights. The particle light absorption coefficient was determined at three different wavelengths with Continuous Light Absorption Photometers (CLAP). They were calibrated with the dual wavelength photo-thermal interferometric measurement of the aerosol light-absorption coefficient in the laboratory. The particle size distributions above 0.3 µm diameter were measured with two Grimm 11-D Optical Particle Size Spectrometers (OPSS). These measurements were conducted separately for the fine aerosol fraction and the enriched coarse fraction using an isokinetic inlet and a pseudo-virtual impactor, respectively. The aerosol light scattering and backscattering coefficients were measured with an Ecotech Aurora 4000 nephelometer. The instrument used a separate isokinetic inlet and was calibrated prior to and its calibration validated after the campaign with CO2. We have measured the total and diffuse solar irradiance with a DeltaT SPN1 pyranometer. CO2 concentration, temperature, aircraft GPS position altitude, air and ground speed were also measured. The in-situ single-scattering albedo Angstrom exponent and the lidar depolarization ratio will be compared as two independent parameters indicating the presence of Saharan dust. We will show differences between homogeneous Saharan dust layer in space (horizontally and vertically) and time and events featuring strong horizontal gradients in aerosol composition and concentration, and layering in the vertical direction. These layers often less than 100 m thick, separated by layers of air with no dust. Complex mixtures of aerosols in the outflow of Saharan dust over the Atlantic Ocean in the tropics will be characterized. We will show the in-situ atmospheric heating/cooling rate and provide insight into the regional and local effects of this heating of the dust layers. These measurements will support of the research on evolution, dynamics, and predictability of tropical weather systems and provide input into and verification of the climate models.
Keywords: mineral dust, climate change, heating rate, black carbon, Aeolus satellite, airborne measurements
Published in RUNG: 21.12.2023; Views: 470; Downloads: 4
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5.
Contribution of APOBEC proteins 3A and 3B to the oncogenicity of HPV viruses
Nika Marija Lovšin, Fabio Lapenta, Urša Pečar Fonović, Katerina Jazbec, Elvira Maličev, Martina Bergant Marušič, 2023, published scientific conference contribution abstract

Keywords: APOBEC, HPV, oncogenicity, gene expression
Published in RUNG: 10.10.2023; Views: 620; Downloads: 9
.pdf Full text (7,73 MB)

6.
JATAC/CAVA-AW Aeolus Cal/Val airborne campaign dataset
Jesús Yus-Díez, Griša Močnik, Luka Drinovec, Marija Bervida, Blaž Žibert, Uroš Jagodič, Matevž Lenarčič, complete scientific database of research data

Abstract: Light aircraft (WT10 - experimental) with position and windspeed variables provided by onboard GPS, as well as additional meteorological sensors. The aircraft was mounted with a: a sunshine pyranometer type SPN1 (Delta-T Devices Ltd), a polar integrating nephelometer AURORA 4000 (Ecotech Pty Ltd), and had a dual sampling line aircraft for measurements at the fine and coarse fraction of the absorption by two Continuous Light Absorption Photometer (CLAPS, by Haze Instruments d.o.o.) and the particle size distribution by two optical particle counters (OPC, model 11D, GRIMM Technologies). The pyranometer provides measurements of the global, direct and diffuse irradiance for a radiation spectrum range between 400 and 2700nm with a 1s time resolution. The polar integrating nephelometer measures the scattering coefficients of particles at three wavelengths (450, 525 and 635 nm) and multiple angles (two selected for the campaign: 0, 90deg) with a 5s time resolution. The CLAP photometers measure the absorption coefficient by aerosol particles at three wavelengths (467, 529 and 653 nm) with a 1s time resolution. The OPC measurements provide the number and mass concentration of aerosol particles for 31 bins in the size range between 0.253 and 35.15 micrometers with a 6s time resolution. The 2021 and 2022 campaigns are found at: http://www.worldgreenflight.com/glwf.php#to-2021 http://www.worldgreenflight.com/glwf.php#to-2022-jatac
Keywords: Aeolus satellite, Saharan dust, aerosol, calibration, validation
Published in RUNG: 27.09.2023; Views: 722; Downloads: 6
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7.
IZDELAVA DINAMIČNE IN ODZIVNE SPLETNE STRANI Z UPORABO FRONT-END RAZVOJNEGA OKVIRA IN SISTEMA ZA UPRAVLJANJE VSEBIN
Marija Nešović, 2023, undergraduate thesis

Abstract: Cilj diplomske naloge je raziskati teoretične vidike in praktično uporabo tehnologije spletnega razvoja Bootstrap in sistema za upravljanje vsebin Umbraco pri izdelavi dinamične in odzivne spletne strani. V prvem delu naloge bomo podrobno raziskali značilnosti Bootstrap-a in Umbraco CMS ter preučili njihovo integracijo. Bootstrap je odprtokodni okvir, ki omogoča hitro in enostavno oblikovanje privlačnih in odzivnih spletnih vmesnikov. Umbraco CMS pa je orodje za upravljanje vsebin, ki olajša urejanje in objavljanje spletnih vsebin brez poseganja v programiranje. Poudarek bo na pridobivanju temeljnega razumevanja obeh tehnologij in njuni uporabi za izgradnjo sodobnih spletnih vmesnikov. V drugem delu naloge smo dejansko ustvarili dinamično in odzivno spletno stran z uporabo Bootstrap-a in Umbraco CMS. Spletna stran bo vsebovala uporabniški vmesnik, ki bo prilagodljiv različnim napravam, in bo omogočala enostavno posodabljanje vsebine preko Umbraco CMS. Z raziskovanjem in praktično izdelavo dinamične spletne strani bomo poglobili razumevanje uporabe Bootstrap-a in Umbraco CMS ter prepoznali prednosti in morebitne izzive pri njuni integraciji.
Keywords: Bootstrap, Umbraco CMS, dinamična spletna stran, odzivna spletna stran, uporabniška izkušnja, spletno oblikovanje, spletni razvoj, CSS, HTML, Java Script
Published in RUNG: 22.09.2023; Views: 506; Downloads: 10
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8.
APOBEC proteins play an important role in human papillomavirus infection and oncogenesis
Martina Bergant Marušič, Fabio Lapenta, Nika Lovšin, 2023, published scientific conference contribution abstract (invited lecture)

Keywords: HPV, APOBEC, oncogenesis, infection
Published in RUNG: 20.07.2023; Views: 779; Downloads: 7
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9.
Investigation of Aerosol Types and Vertical Distributions Using Polarization Raman Lidar over Vipava Valley
Longlong Wang, Marija Bervida, Samo Stanič, Klemen Bergant, Asta Gregorič, Luka Drinovec, Zhenping Yin, Yang Yi, Detlef Müller, Xuan Wang, 2022, original scientific article

Abstract: Aerosol direct radiative forcing is strongly dependent on aerosol distributions and aerosol types. A detailed understanding of such information is still missing at the Alpine region, which currently undergoes amplified climate warming. Our goal was to study the vertical variability of aerosol types within and above the Vipava valley (45.87◦ N, 13.90◦ E, 125 m a.s.l.) to reveal the vertical impact of each particular aerosol type on this region, a representative complex terrain in the Alpine region which often suffers from air pollution in the wintertime. This investigation was performed using the entire dataset of a dual-wavelength polarization Raman lidar system, which covers 33 nights from September to December 2017. The lidar provides measurements from midnight to early morning (typically from 00:00 to 06:00 CET) to provide aerosol-type dependent properties, which include particle linear depolarization ratio, lidar ratio at 355 nm and the aerosol backscatter Ångström exponent between 355 nm and 1064 nm. These aerosol properties were compared with similar studies, and the aerosol types were identified by the measured aerosol optical properties. Primary anthropogenic aerosols within the valley are mainly emitted from two sources: individual domestic heating systems, which mostly use biomass fuel, and traffic emissions. Natural aerosols, such as mineral dust and sea salt, are mostly transported over large distances. A mixture of two or more aerosol types was generally found. The aerosol characterization and statistical properties of vertical aerosol distributions were performed up to 3 km.
Keywords: valley air pollution, aerosol vertical distributions, lidar remote sensing, aerosol identification
Published in RUNG: 21.07.2022; Views: 1320; Downloads: 28
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10.
Bora flow characteristics in a complex valley environment
Marija Bervida, Samo Stanič, Griša Močnik, Longlong Wang, Klemen Bergant, Xiaoquan Song, 2021, original scientific article

Abstract: This paper complements the existing studies of Bora flow properties in the Vipava valley with the study of Bora turbulence in a lower region of the troposphere. The turbulence characteristics of Bora flow were derived from high resolution Doppler wind lidar measurements during eight Bora wind episodes that occurred in November and December 2019. Based on the vertical profiles of wind velocity, from 80 to 180 m above the valley floor, the turbulence intensity related to all three spatial directions and the along-wind integral length scales related to three velocity components were evaluated and compared to the approximations given in international standards. The resulting turbulence characteristics of Bora flow in a deep mountain valley exhibited interesting behaviour, differing from the one expected and suggested by standards. The intensity of turbulence during Bora episodes was found to be quite strong, especially regarding the expected values for that particular category of terrain. The specific relationship between along-wind, lateral and vertical intensity was evaluated as well. The scales of turbulence in the along-wind direction were found to vary widely between different Bora episodes and were rather different from the approximations given by standards, with the most significant deviations observed for the along-wind length scale of the vertical velocity component. Finally, the periodicity of flow structures above the valley was assessed, yielding a wide range of possible periods between 1 and 10 min, thus confirming some of the previous observations from the studies of Bora in the Vipava valley.
Keywords: doppler wind lidar, Bora wind, turbulence intensity, complex terrain, turbulence integral length scale
Published in RUNG: 05.11.2021; Views: 1936; Downloads: 42
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