Przezroczystość trzcinowiska w różnych warunkach rozproszenia promieniowania słonecznego

Diffused solar radiation increases ecosystem productivity. One of the explanations for this phenomenon is the fact that this type of radiation penetrates the vegetation layer more efficiently, thus changing radiation conditions under the plant canopy. The study of reed transparency under different radiation diffusion conditions makes it possible to estimate the amount of radiation energy that reaches plants living under the reed canopy. The presented radiation parameters were obtained using the SS1 probe (Delta-T Devices Ltd. UK.). The measurements were carried out in September 2014 in a reed canopy in the Rzecin peatland (52°45′N, 16°18′E, 54 m a.s.l.). Analyses showed that the transparency of the reed canopy (Tr) is directly proportional to the degree of diffusion (D*) of the radiation which reaches the plant surface and the reed Tr value is always greater at cloudy conditions than during periods of low radiation diffusion. At the same time, Tr is inversely proportional to the leaf area index (LAI). Under high diffusion of radiation the plants growing under the reed canopy gain approximately 38% radiation energy in comparison with periods characterised by low values of D*.Rozproszone promieniowanie słoneczne powoduje wzrost produktywności ekosystemów. Jest to spowodowane między innymi tym, że ten rodzaj promieniowania lepiej penetruje roślinność, zmieniając tym samym warunki radiacyjne pod okapem roślin. Badanie przezroczystości trzcinowiska w różnych warunkach rozpraszania promieniowania pozwala na określenie warunków (ilości docierającej energii promienistej) bytowania roślin żyjących pod okapem trzcin. Prezentowane dane są wynikiem pomiarów wykonanych za pomocą sondy SS1 firmy Detla-T służącej do oceny warunków oraz parametrów radiacyjnych roślin. Badania przeprowadzono we wrześniu 2014 r. w łanie trzcin na torfowisku w Rzecinie (52°45′N, 16°18′E, 54 m n.p.m.). W wyniku przeprowadzonych analiz stwierdzono, iż przezroczystość trzcinowiska (Tr) jest wprost proporcjonalna do stopnia rozproszenia promieniowania docierającego do powierzchni roślin (D*), a jej wartość jest zawsze większa w warunkach D* = 1.0 od wartości Tr w okresach o małym rozpraszaniu promieniowania. Jednocześnie Tr jest odwrotnie proporcjonalne do wartości współczynnika ulistnienia (LAI). W warunkach pełnego rozproszenia ilość energii promienistej docierającej do roślin znajdujących się pod okapem trzcin wzrasta średnio o ok. 38% w porównaniu do okresów o niskich wartościach D*

Modification of local urban aerosol properties by long-range transport of biomass burning aerosol

During August 2016, a quasi-stationary high-pressure system spreading over Central and North-Eastern Europe, caused weather conditions that allowed for 24/7 observations of aerosol optical properties by using a complex multi-wavelength PollyXT lidar system with Raman, polarization and water vapour capabilities, based at the European Aerosol Research Lidar Network (EARLINET network) urban site in Warsaw, Poland. During 24-30 August 2016, the lidar-derived products (boundary layer height, aerosol optical depth, Ångström exponent, lidar ratio, depolarization ratio) were analysed in terms of air mass transport (HYSPLIT model), aerosol load (CAMS data) and type (NAAPS model) and confronted with active and passive remote sensing at the ground level (PolandAOD, AERONET, WIOS-AQ networks) and aboard satellites (SEVIRI, MODIS, CATS sensors). Optical properties for less than a day-old fresh biomass burning aerosol, advected into Warsaw's boundary layer from over Ukraine, were compared with the properties of long-range transported 3-5 day-old aged biomass burning aerosol detected in the free troposphere over Warsaw. Analyses of temporal changes of aerosol properties within the boundary layer, revealed an increase of aerosol optical depth and Ångström exponent accompanied by an increase of surface PM10 and PM2.5. Intrusions of advected biomass burning particles into the urban boundary layer seem to affect not only the optical properties observed but also the top height of the boundary layer, by moderating its increase. © 2018 by the authors

A Decade of Poland-AOD Aerosol Research Network Observations

The Poland-AOD aerosol research network was established in 2011 to improve aerosol–climate interaction knowledge and provide a real-time and historical, comprehensive, and quantitative database for the aerosol optical properties distribution over Poland. The network consists of research institutions and private owners operating 10 measurement stations and an organization responsible for aerosol model transport simulations. Poland-AOD collaboration provides observations of spectral aerosol optical depth (AOD), Ångstrom Exponent (AE), incoming shortwave (SW) and longwave (LW) radiation fluxes, vertical profiles of aerosol optical properties and surface aerosol scattering and absorption coefficient, as well as microphysical particle properties. Based on the radiative transfer model (RTM), the aerosol radiative forcing (ARF) and the heating rate are simulated. In addition, results from GEM-AQ and WRF-Chem models (e.g., aerosol mass mixing ratio and optical properties for several particle chemical components), and HYSPLIT back-trajectories are used to interpret the results of observation and to describe the 3D aerosol optical properties distribution. Results of Poland-AOD research indicate progressive improvement of air quality and at mospheric turbidity during the last decade. The AOD was reduced by about 0.02/10 yr (at 550 nm), which corresponds to positive trends in ARF. The estimated clear-sky ARF trend is 0.34 W/m2/10 yr and 0.68 W/m2/10 yr, respectively, at TOA and at Earth’s surface. Therefore, reduction in aerosol load observed in Poland can significantly contribute to climate warming

A Decade of Poland-AOD Aerosol Research Network Observations

The Poland-AOD aerosol research network was established in 2011 to improve aerosol–climate interaction knowledge and provide a real-time and historical, comprehensive, and quantitative database for the aerosol optical properties distribution over Poland. The network consists of research institutions and private owners operating 10 measurement stations and an organization responsible for aerosol model transport simulations. Poland-AOD collaboration provides observations of spectral aerosol optical depth (AOD), Ångstrom Exponent (AE), incoming shortwave (SW) and longwave (LW) radiation fluxes, vertical profiles of aerosol optical properties and surface aerosol scattering and absorption coefficient, as well as microphysical particle properties. Based on the radiative transfer model (RTM), the aerosol radiative forcing (ARF) and the heating rate are simulated. In addition, results from GEM-AQ and WRF-Chem models (e.g., aerosol mass mixing ratio and optical properties for several particle chemical components), and HYSPLIT back-trajectories are used to interpret the results of observation and to describe the 3D aerosol optical properties distribution. Results of Poland-AOD research indicate progressive improvement of air quality and at mospheric turbidity during the last decade. The AOD was reduced by about 0.02/10 yr (at 550 nm), which corresponds to positive trends in ARF. The estimated clear-sky ARF trend is 0.34 W/m2/10 yr and 0.68 W/m2/10 yr, respectively, at TOA and at Earth’s surface. Therefore, reduction in aerosol load observed in Poland can significantly contribute to climate warming