Joanna Uscka-Kowalkowska

DAILY MINIMUM AND MAXIMUM AIR TEMPERATURE IN POLAND IN THE YEARS 1951–2005

In this study grid data of daily maximum and minimum air temperatures taken from the NCEP/NCAR reanalysis for the territory of Poland for the years 1951–2005 have been used as a basis for an analysis of the spatial distribution of daily maximum and minimum air temperature, the frequency of characteristic days and the variability of these parameters in the period analysed. The results obtained were then compared to the variability in atmospheric circulation in Europe, described by the North Atlantic Oscillation (NAO) index.

Long‐term and seasonal variability of the aerosol optical depth at Mount Kasprowy Wierch (Poland)

This paper presents the results of long-term observations (1964–2003) of direct solar radiation, to determine aerosol optical depth (AOD), made with a Linke-Feussner actinometer at the Tatra Mountain Meteorological Observatory on Mount Kasprowy Wierch (1991 m above sea level, 49.233°N, 19.982°E). To this end, broadband direct solar flux (0.29–2.9 µm) and wideband solar radiation measured with OG530 and RG630 filters are used to estimate the broadband and wideband (0.53–0.63 µm) AOD. The inversion algorithm used is based on the MODTRAN (MODerate resolution atmospheric TRANsmission) radiative transfer model applied to estimate direct flux for aerosol-free atmosphere. Total water vapor content, which accounts for the largest extinction of clear-sky direct flux, was obtained by radio sounding from the Poprad-Ganovce station (33 km from Mount Kasprowy Wierch) and from water vapor pressure measurements at the Observatory. The almost 900 clear-sky observations, performed close to noon time, found a significant long-term reduction of AOD. AOD decadal trends were −0.006 (−8 ± 4% [2σ]) with a 95% confidence interval of ± 0.003 and −0.014 (−13 ± 4% [2σ]) with a 95% confidence interval of ± 0.004 for broadband and wideband, respectively. Similar trends, but for years with negligible contamination of volcanic aerosol, are −0.012 (−16 ± 6% [2σ]) and −0.018 (−17 ± 6% [2σ]) with a 95% confidence interval of ± 0.003 and ± 0.004. However, positive AOD trends (from 0 to 0.04 per decade) were found between 1964 and 1983 and negative AOD trends (from −0.016 to −0.035 per decade) were found between 1984 and 2003. Changes of the AOD trends between both periods are associated with global dimming and brightening phenomenon, which took place in the second half of the twentieth century and at the beginning of the 21st century. The long-term mean broadband and wideband AOD were 0.07 ± 0.01 and 0.11 ± 0.02, respectively. Both quantities show a significant annual cycle, with maximum AOD during spring and summer. Very low values during the autumn and winter (about 0.03 for broadband and 0.05–0.06 for wideband) are the result of planetary boundary layer height (defined for the lower elevations), which during this period lies below Mount Kasprowy Wierch itself. The other explanation of low AOD values can be the high frequency (more than 50%) of inversion occurrence below the top of the mountain.

Clear sky atmosphere at cm-wavelengths from climatology data

We utilise ground-based, balloon-borne and satellite climatology data to reconstruct site and season-dependent vertical profiles of precipitable water vapour (PWV). We use these profiles to solve radiative transfer through the atmosphere, and derive atmospheric brightness temperature (

Comparison of the predicted insulation of clothing in Toruń and Koniczynka in the years 1998–2012*

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DIRECT SOLAR RADIATION AND ATMOSPHERIC TURBIDITY IN MIKOŁAJKI IN THE YEARS 1971–1980 AND 1991–2000

) and optical depth (

Comparison of the Linke turbidity factor in Warsaw and in Belsk

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SPATIAL DIFFERENTIATION OF GLOBAL SOLAR RADIATION IN TORUŃ AND ITS SUBURBAN AREA (CENTRAL POLAND) IN 2012

) at centimetre wavelengths. We validate the reconstruction by comparing the model column PWV with photometric measurements of PWV, performed in clear sky conditions pointed towards the Sun. Based on the measurements, we devise a selection criteria to filter the climatology data to match the PWV levels to the expectations of the clear sky conditions. We apply the reconstruction to the location of a Polish 32-metre radio telescope, and characterise

An analysis of the extinction of direct solar radiation on Mt. Kasprowy Wierch, Poland

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Poland’s Climate Extremes Index, 1951–2005

and

Spatial distribution of air temperature in Toruń (Central Poland) and its causes

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