Air quality is of large concern in the city of Krakow, southern Poland. A comprehensive study was launched by us in which two PM fractions (PM
and PM
) were sampled during 1-year campaign, lasting ...from April 21, 2018 to March 19, 2019. A suite of modern analytical methods was used to characterize the chemical composition of the collected samples. The contents of 14 sugars, sugar alcohols and anhydrosugars, 16 polycyclic aromatic hydrocarbons, selected metals and non-metals and ions were analyzed, in addition to organic and elemental carbon content. The carbon isotope composition in both analysed PM fractions, combined with an isotope-mass balance method, allowed to distinguish three main components of carbonaceous emissions in the city: (1) emissions related to combustion of hard coal, (2) emissions related to road transport, and (3) biogenic emissions. The heating season emissions from coal combustion had the biggest contribution to the reservoir of carbonaceous aerosols in the PM
fraction (44%) and, together with the biogenic emission, they were the biggest contributors to the PM
fraction (41% and 44%, respectively). In the non-heating season, the dominant source of carbon in PM
and PM
fraction were the biogenic emissions (48 and 54%, respectively).
Krakow, with an area of 327 km2 and over 750,000 inhabitants, is one of the largest cities in Poland. Within the administrative city borders several anthropogenic CO2 source types are located, ...including car traffic, household coal and natural gas burning, and industrial emissions. Additionally, the biosphere produces its own, seasonally variable, input to the local atmospheric carbon budget. In order to quantify each of CO2 budget contributions to the local atmosphere, a number of analytical and numerical techniques have been implemented. The seasonal variability of CO2 emission from soils around the city has been directly measured using the chamber method; CO2 net flux from an area containing several source types has been measured with a relaxed eddy accumulation—a variation of the eddy covariance method. Global emissions inventory, as well as local statistical data have been utilized to assess anthropogenic component of the budget. As other cities where CO2 budget was quantified, Krakow proved to be a net source of this greenhouse gas, and the calculated annual mean net flux of CO2 to the atmosphere equal 6.1 kg C m−2 is consistent with previous estimations.
Kraków, Poland, is a city with poor air quality, located in the large Wisła (Vistula) valley, and affected by a foehn wind from the Tatra Mountains. We analyzed 14 long episodes of the foehn from the ...periods Sep 2017 - Apr 2018 and Sep 2018 - Apr 2019. Data used included measurements of PM
10
(i.e. particulate matter with an aerodynamic diameter up to 10 µm) concentrations) concentrations, air temperature and relative humidity, wind speed and direction from ground stations and mast measurements up to 100 m a.g.l., along with model analysis results. A non-operational configuration of the AROME CMC (the Application of Research to Operations at Mesoscale canonical model configuration) 1 km x 1 km was applied. A conceptual model concerning the impact of a foehn on urban air pollution was developed. The occurrence of a particular effect of a foehn on the PM
10
spatial-temporal pattern depends on its mode of transfer through the city: a. a foehn flows above the valley where a strong cold air pool and a return flow can be found; b. a foehn enters the valley from the eastern, wider part or from the valley top and destroys the cold air pool; c. gravity waves generated by a foehn are strong enough to enter the western narrower part of the valley and cause large spatial differences in turbulence parameters within the city. The first transfer mode worsens air pollution dispersion conditions throughout the city and leads to large increases in PM
10
levels (from below 50 to 150-200 µg⋅m
−3
), the second mode improves dispersion and leads to large decreases in PM
10
levels (from 150-200 to below 50 µg⋅m
−3
) throughout the city, and the third generates large spatial differences in PM
10
levels (50-70 µg⋅m
−3
) within the city. There is no single effect of a foehn on air pollution dispersion conditions.
Unmanned aerial vehicle (UAV) photogrammetry allows the generation of orthophoto and digital surface model (DSM) rasters of terrain. However, DSMs of water bodies mapped using this technique often ...reveal distortions in the water surface, thereby impeding the accurate sampling of water surface elevation (WSE) from DSMs. This study investigates the capability of deep neural networks to accommodate the aforementioned perturbations and effectively estimate WSE from photogrammetric rasters. Convolutional neural networks (CNNs) were employed for this purpose. Two regression approaches utilizing CNNs were explored: direct regression employing an encoder and a solution based on prediction of the weight mask by an autoencoder architecture, subsequently used to sample values from the photogrammetric DSM. The dataset employed in this study comprises data collected from five case studies of small lowland streams in Poland and Denmark, consisting of 322 DSM and orthophoto raster samples. A grid search was employed to identify the optimal combination of encoder, mask generation architecture, and batch size among multiple candidates. Solutions were evaluated using two cross-validation methods: stratified k-fold cross-validation, where validation subsets maintained the same proportion of samples from all case studies, and leave-one-case-out cross-validation, where the validation dataset originates entirely from a single case study, and the training set consists of samples from other case studies. Depending on the case study and the level of validation strictness, the proposed solution achieved a root mean square error (RMSE) ranging between 2 cm and 16 cm. The proposed method outperforms methods based on the straightforward sampling of photogrammetric DSM, achieving, on average, an 84% lower RMSE for stratified cross-validation and a 62% lower RMSE for all-in-case-out cross-validation. By utilizing data from other research, the proposed solution was compared on the same case study with other UAV-based methods. For that benchmark case study, the proposed solution achieved an RMSE score of 5.9 cm for all-in-case-out cross-validation and 3.5 cm for stratified cross-validation, which is close to the result achieved by the radar-based method (RMSE of 3 cm), which is considered the most accurate method available. The proposed solution is characterized by a high degree of explainability and generalization.
The article presents the results of statistical analyzes of meteorological and atmospheric radon concentration measurements carried out in Krakow in the years 2004–2013. Based on the diurnal ...variability, an estimation of the height of the nocturnal boundary layer was performed and compared with the ERA5 data. The average concentration of radon in the air of that period in Kraków was equal to (5.262 ± 0.017) Bqm
−3
. The diurnal and seasonal variability of radon concentration was found. The correlation of meteorological parameters calculated based on hourly mean data was analyzed. The correlations obtained were statistically significant, for wind speed (r= -0.38,
p
<0.001), and air humidity (r=0.33,
p
<0.001). The possibility of determining of the nocturnal boundary layer height on the basis of radon measurements has been confirmed; however, the calculation model needs to be refined.
Unmanned aerial vehicle (UAV) thermal imagery offers several advantages for environmental monitoring, as it can provide a low-cost, high-resolution, and flexible solution to measure the temperature ...of the surface of the land. Limitations related to the maximum load of the drone lead to the use of lightweight uncooled thermal cameras whose internal components are not stabilized to a constant temperature. Such cameras suffer from several unwanted effects that contribute to the increase in temperature measurement error from ±0.5 °C in laboratory conditions to ±5 °C in unstable flight conditions. This article describes a post-processing procedure that reduces the above unwanted effects. It consists of the following steps: (i) devignetting using the single image vignette correction algorithm, (ii) georeferencing using image metadata, scale-invariant feature transform (SIFT) stitching, and gradient descent optimisation, and (iii) inter-image temperature consistency optimisation by minimisation of bias between overlapping thermal images using gradient descent optimisation. The solution was tested in several case studies of river areas, where natural water bodies were used as a reference temperature benchmark. In all tests, the precision of the measurements was increased. The root mean square error (RMSE) on average was reduced by 39.0% and mean of the absolute value of errors (MAE) by 40.5%. The proposed algorithm can be called self-calibrating, as in contrast to other known solutions, it is fully automatic, uses only field data, and does not require any calibration equipment or additional operator effort. A Python implementation of the solution is available on GitHub.
This article aims to compare the molar fraction of atmospheric CO
measured in southern Poland, specifically in Gliwice (an urban area), Kraków (an urban area), and Kasprowy Wierch (a mountain ...environment) from August 2022 to March 2023. The study examines diurnal, monthly and seasonal variations in the molar fraction of CO
. Monthly and diurnal average CO
air mole fraction data are reported for Gliwice, Kraków, and Kasprowy Wierch during the specified period. The results reveal greater fluctuations in CO
amplitude in urban areas compared to the mountain environment. Significant differences in diurnal, nocturnal, monthly and seasonal variabilities of atmospheric CO
are observed in the urban sites. The findings suggest that the biosphere may act as a dominant source of local CO
in summer and fall, while other local or regional anthropogenic sources could impact CO
levels during winter and early spring, prior to the vegetation period. Additionally, this paper discusses challenges encountered during the use of a low-cost system (CARBOCAP GMP-343) for measuring CO
levels in the urban area of Gliwice in 2022.
The concentration of indoor suspended particulate matter is considered to be one of the main factors that affect health and quality of life. In Poland, in response to the pressure of public opinion, ...a few thousand air purifiers have been installed in public buildings where children spend time. However, another factor that also impacts upon the quality of indoor air, namely increased CO2 mixing ratios, is frequently overlooked. The only way to remove CO2 excess from interiors is through intensive ventilation. This is often an action at odds with the need to maintain low concentrations of particulate matter in indoor air. Two methods are presented to assess the rate of air exchange using CO2 or particulate matter as a tracer. One of the methods using indoor/outdoor PM (particulate matter) concentrations is based on the use of box models for analysis. The second one uses indoor CO2 concentration change analysis. At the tested locations, they showed large deviations of the determined values of the air exchange coefficients from its limits. Both methods showed consistent ventilation parameters estimation.
Winter smog episodes are a severe problem in many cities around the world. The following two mechanisms are responsible for influencing the level of pollutant concentrations: emission of pollutants ...from different sources and associated processes leading to formation of secondary aerosols in the atmosphere and meteorology, including advection, which is stimulated by horizontal wind, and convection, which depends on vertical air mass movements associated with boundary layer stability that are determined by vertical temperature and humidity gradients. The aim of the present study was to evaluate the performance of an unmanned aerial vehicle (UAV)-based measurement system developed for investigation of urban boundary layer dynamics. The evaluation was done by comparing the results of temperature, relative humidity, wind speed and particulate matter fraction with aerodynamic diameter below 10 μm (PM
) concentration vertical profiles obtained using this system with two reference meteorological stations: Jagiellonian University Campus (JUC) and radio transmission tower (RTCN), located in the urban area of Krakow city, Southern Poland. The secondary aim of the study was to optimize data processing algorithms improving the response time of UAV sensor measurements during the ascent and descent parts of the flight mission.