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Integrated precipitable water from GPS observations and CIMEL sunphotometer measurements at CGO Belsk

Kruczyk M., Liwosz T., Pietruczuk A.

Reports on Geodesy and Geoinformatics

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2017

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Vol. 103

46--65

EN

This paper describes results of integrated precipitable water co-located measurements from two techniques: GPS solution and CIMEL-318 sun-photometer. Integrated Precipitable Water (IPW) is an important meteorological parameter and is derived from GPS tropospheric solutions for GPS station at Central Geophysical Observatory (CGO), Polish Academy of Sciences (PAS), Belsk and compared with sunphotometer (CIMEL-318 device by Cimel Electronique) data provided by Aerosol Robotic Network (AERONET). Two dedicated and independent GPS solutions: network solution in the sub-network of European Permanent Network (EPN) and precise point positioning solution have been made to obtain tropospheric delays. The quality of dedicated tropospheric solutions has been verified by comparison with EPN tropospheric combined product. Several IPW comparisons and analyses revealed systematic difference between techniques (difference RMS is over 1 mm). IPW bias changes with season: annual close to 1 mm IPW (and semi-annual term also present). IPW bias is a function of atmospheric temperature. Probable cause of this systematic deficiency in solar photometry as IPW retrieval technique is a change of optical filter characteristics in CIMEL.

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The Long-Term (1964-2014) Variability of Aerosol Optical Thickness and its Impact on Solar Irradiance Based on the Data Taken at Belsk, Poland

Posyniak M., Szkop A., Pietruczuk A., Podgórski J., Krzyścin J.

Acta Geophysica

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2016

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Vol. 64, no. 5

1858--1874

EN

Measurements of the Linke turbidity factor (LTF) were performed at Belsk (20.78°E, 51.83°N), Poland, since 1964. This data is used to retrieve broadband aerosol optical thickness normalized to the air mass equal to 2 (BAOT2). A linear analysis of the BAOT2 changes reveals an upward trend of 0.023±0.017(2σ) in the 1964-1975 period, a downward trend of –0.051±0.017(2σ) in the 1976-1991 period, and afterwards a statistically insignificant trend of –0.009 ± 0.014(2σ). Such pattern may be related to the economic changes in Poland (changing emissions and environmental policies). The elevated BAOT2 values, excluded from the trend, are found in 1984 and 1992 due to the volcanic eruptions of El Chichon and Mt. Pinatubo, respectively. Past AOT values at 340 and 500 nm are reconstructed using a linear relationship found between AOT and BAOT2. The reconstructed data is used by the radiative transfer models to estimate a response of the total solar and erythemal radiation to the changes in the atmospheric aerosols at Belsk.

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Classification of Aerosol over Central Europe by Cluster Analysis of Aerosol Columnar Optical Properties and Backward Trajectory Statistics

Szkop A., Pietruczuk A., Posyniak M.

Acta Geophysica

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2016

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Vol. 64, no. 6

2650--2676

EN

A cluster analysis is applied to the Aerosol Robotic Network (AERONET) data obtained at Belsk, Poland, as well as three nearby Central European stations (Leipzig, Minsk and Moldova) for estimation of atmospheric aerosol types. Absorption Ångstrom exponent (AAE), aerosol optical thickness (AOT) and extinction Ångstrom exponent (EAE) parameters are used. Clustering in both 2D (AOT, EAE) and 3D (AOT, EAE, AAE) is investigated. A method of air mass backward trajectory analysis is then proposed, with the receptor site at Belsk, to determine possible source regions for each cluster. Four dominant aerosol source regions are identified. The biomass burning aerosol source is localized in the vicinity of Belarusian-Ukrainian border. Slovakia and northern Hungary are found to be the source of urban/industrial pollutants. Western Poland and eastern Germany are the main sources of polluted continental aerosols. The most differentiated source region of Scandinavia, Baltic Sea and Northern Atlantic, associated with lowest values of AOT, corresponds to clean continental and possibly maritime type aerosols.

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Analysis of particulate matter concentrations in Mazovia region, central Poland, based on 2007-2010 data

Pietruczuk A., Jarosławski J.

Acta Geophysica

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2013

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Vol. 61, no. 2

445--462

EN

Measurement results of PM10 (par ticulate matter with diameters below 10µm) concentrations performed at four stations in central Poland (2007-2010) were analyzed in terms of levels and distributions of concentrations, the number of exceedances of the limit values and the causes of these exceedances. PM10 levels were similar at suburban and rural stations, except of one station located in the vicinity of a busy street. The median of PM10 concentration ranged from 26µg/m³ at suburban station to 44µg/m³ at Warsaw Kerb station. Seasonal variability analysis of PM10 concentration revealed an additional maximum beyond the usual autumn-winter one. This maximum occurred in April at all stations, and corresponded to seasonal wildfires activity and dust activation in Eastern Europe. Cluster analysis of back-traj ectories revealed that PM10 concen- trations depend on the direction of advection of the incoming air; the highest values are registered for air of regional and southern origins, while the lowest are for the airma sses coming from the north and north-west direction.

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Variability of aerosol properties during the 2007–2010 spring seasons over central Europe

Pietruczuk A., Chaikovsky A.

Acta Geophysica

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2012

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Vol. 60, no. 5

1338-1358

EN

Aerosol optical properties have been studied for spring seasons when increased values of PM10 are registered. Measurements of aerosol optical properties were taken by collocated lidar and sun-photometers at Belsk, Poland, and Minsk, Belarus. A significant increase of registered aerosol optical thickness (AOT) was found during episodes with elevated PM10 concentrations. An increase of AOT at 1020 nm amounted to 50% in the case of Minsk and 18% in the case of Belsk, while an increase of AOT at 400 nm was 66% and 33%, respectively. We noted an increase of ?ngstrom exponent by 6% at both stations and no significant increase of single scattering albedo. The LIDAR measurements together with NAAPS model results and backtrajectory analysis suggest that both the biomass burning products and the Saharan dust are responsible for increased PM10 concentrations and large AOT values during spring time. The smoke aerosol is transported over Central Europe mainly in the boundary layer, increasing both PM10 concentration and AOT. The dust aerosol transported in the free troposphere slightly affects the AOT values only. Statistically significant correlation between PM10 concentration and AOT was found during reporting period.

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On the origin of seasonal variation of aerosol optical thickness in UV range over Belsk, Poland

Jarosławski J., Pietruczuk A.

Acta Geophysica

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2010

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Vol. 58, no. 6

1134-1146

EN

Aerosol optical thickness (AOT) and seasonal variation of AOT over Belsk, Poland, in the UV wavelength range (310-380 nm) have been analysed using results of measurements by Brewer spectrophotometer No. 064 and Cimel sunphotometer data for the 2002-2007 period. The comparison of AOT derived from direct Sun measurements by Brewer spectrophotometer in the 310-320 nm range and retrieved from Cimel measurements at longer wavelengths shows good correlation (R = 0.96), with overestimation of retrieved values compared to the measured ones by about 6%. Basing on aerosol microphysical properties taken from almucantar retrievals and Mie theory, optical properties of aerosol in the UV range has been calculated. Analysis of seasonal variation of AOT at Belsk reveals two maxima: in April and July-August. Analysis of backtrajectories in conjunction with analysis of fire maps from Fire Information For Resource Management System shows that these seasonal maxima are connected with seasonal biomass burning in Eastern and Southern Europe.

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The lidar ratio derived from sun-photometer measurements at Belsk Geophysical Observatory

Pietruczuk A., Podgórski J.

Acta Geophysica

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2009

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Vol. 57, no. 2

476-493

EN

The lidar ratios at 500 and 1020 nm were derived from POM 01L sun-sky scanning photometer measurements taken at Belsk Geophysical Observatory (long. 20°47', lat. 51°50') in the period from 2002 to 2006. The most frequently occurring lidar ratio values for the study period are 50 sr and 30 sr at 500 nm and 1020 nm, respectively. Calculations of lidar ratios for summer and winter seasons have been made as well. Back trajectory analysis was also performed to final aerosol source of origin.

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Investigation of collisions between electrons and excited atoms of potassium, rubidium and caesium

Pietruczuk A, Stacewicz T, Wilska M

Optica Applicata

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2006

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Vol. 36, nr 4

s. 489--497

EN

Results of measurements of the rate constants for electron impact induced transitions between selected levels of potassium (4P–6P), rubidium (5P–7P) and caesium (6P–8P and 6P–9P) are presented. The experiment was done in helium plasma produced by electric discharge. The plasma was doped with the atoms of interest at a concentration of about 1011 cm–3. The alkali atoms were excited to resonance level by a laser pulse. The rate constants for the investigated transitions were determined by the analysis of atomic fluorescence. The electron temperature was measured using a double probe method.