Long-wave radiation balances of grassy surface and bare soil in Wrocław

Abstract

The paper goal is to show diurnal, seasonal and year to year variability of long-wave radiation balances of two contrasting types of active surfaces – grassy and bare soil in the context of bioclimatic and ecological role of plant areas in a big city. The analyses was conducted on example of Wrocław (SW Poland) and the experimental results were obtained from about twelve-year period of measurements. The average annual values of fluxes of the main components of these long-wave balances reached: 368.6 W/m2 for the long-wave radiation of bare soil, 363.6 W/m2 for the long-wave radiation of grassy surface and 322.9 W/m2 for the downward atmospheric radiation. These differences between values of bare soil and grassy surfaces varied during the year from negative values in winter to positive values in spring and the summer. The final conclusion of the study is an important empirical argument for urban planning to extend share of plant areas in cities and urban agglomerations.

Estimating Daily Global Solar Radiation with No Meteorological Data in Poland

“…3, and the maximal difference between MABE for the analyzed models does not exceed 0.13 MJ•m −2 . Except for Wieluń and Włodawa stations, similar values of MABE were obtained for Equations (1) and (3). Figure 2 shows the compatibility of the measured and calculated values of long-term monthly average daily solar radiation.…”

“…MAPE ranges from 4.16% to 8.71% (Model (1)), from 5.68% to 14.20% (Model (2)), and from 4.02% to 9.15% (Model (3)). The highest values of MAPE were obtained for Equation (2), whereas they were similar for Equations (1) and (3).…”

“…However, in Poland, possibly mainly due to the limited data accessibility, solar radiation studies are rare and based on individual data series [1][2][3][4][5]. The exception is a paper concerning changes in solar radiation in the years 1961-1995 at six stations [6].…”

Atmospheric water infiltration intensity in non-rainfall periods under conditionsof varied soil moisture

“…This is a measure of water vapour availability that depends on such factors as e.g. wind direction and velocity (Beysens et al, 2005;Bryś, 2013;Malek, 2003;Muselli et al, 2009;Zhang et al, 2015). The intensity of water condensation on soil surface is described by Stephan's theory of diffusion, the formal notation of which is expressed by the relation (Brouwers, 1992;Frank-Kamenetskii, 1955):…”

Monthly average daily diffuse solar radiation in Poland within the period 2005–2015

“…The published results of research in Poland into diffuse solar radiation are limited. Bryś stated that in Wroclaw in the middle of 70s diffuse solar radiation trends changed from raise to fall phase [10]. In total solar radiation analysis in Poland, depending on station and the length of the time series, different trends were detected.…”