Browsing by Subject "SOLAR-RADIATION"

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  • Hartikainen, Saara M.; Jach, Agnieszka; Grane, Aurea; Robson, Thomas Matthew (2018)
  • Väärikkälä, Sofia Susanna; Hänninen, Laura Talvikki; Nevas, Mari Anne (2019)
    Simple Summary Official on-farm inspections are carried out throughout the European Union every year to ensure farm compliance with animal welfare standards. The aim of this study was to analyze Finnish inspection data in order to find out how well cattle and pig farms comply with animal welfare standards, to reveal the most common non-compliances and to identify possible farm risk factors. About every fourth inspected Finnish cattle and pig farm did not comply with the animal welfare standards. Examples of factors that increased the risk of non-compliance were small herd size, tie-stall housing and outdoor rearing. Inadequate lying area in cattle farms and a lack of enrichment material in pig farms were the most common non-compliances. The regional differences found may indicate differences in inspectors' interpretations or ways in conducting inspections. As the official inspection reports contain valuable information about the welfare problems on farms, the reports should be better utilized in risk analysis, in targeting farmer education, and in making the inspections more uniform. Abstract The competent authorities of the Member States of the European Union are required to perform animal welfare inspections on livestock farms. The data obtained from these official inspections performed in Finnish cattle and pig farms in 2010-2015 were used with the aim of estimating the prevalence of the most common non-compliances and identifying underlying risk factors. The prevalence of non-compliant cattle and pig farms was 24.2% and 27.9%, respectively. In cattle, the most common problem was an inadequate lying area followed by deficient housing conditions for calves; in pigs, it was a lack of enrichment material. The non-compliances concerning cattle were most frequently detected in autumn and in farms with small herd size, with tie-stall housing and outdoor rearing year-round. The pig farms with a farrow-to-finish unit had a higher prevalence of non-compliances than other production types. The prevalence of the non-compliant farms differed notably between the regions. It can be concluded that the cattle welfare inspections should be performed with a focus on the cold and rainy seasons and at small farms, whereas the pig welfare inspections should mainly focus on farrow-to-finish units. The data received from official inspections should be efficiently utilized in the development of animal welfare inspection system, with the aim of risk-based, consistent and uniform inspections. In addition, the data should be utilized in targeting information for farmers.
  • Barnes, Paul W.; Williamson, Craig E.; Lucas, Robyn M.; Robinson, Sharon A.; Madronich, Sasha; Paul, Nigel D.; Bornman, Janet F.; Bais, Alkiviadis F.; Sulzberger, Barbara; Wilson, Stephen R.; Andrady, Anthony L.; McKenzie, Richard L.; Neale, Patrick J.; Austin, Amy T.; Bernhard, Germar H.; Solomon, Keith R.; Neale, Rachel E.; Young, Paul J.; Norval, Mary; Rhodes, Lesley E.; Hylander, Samuel; Rose, Kevin C.; Longstreth, Janice; Aucamp, Pieter J.; Ballare, Carlos L.; Cory, Rose M.; Flint, Stephan D.; de Gruijl, Frank R.; Haeder, Donat-P; Heikkila, Anu M.; Jansen, Marcel A. K.; Pandey, Krishna K.; Robson, T. Matthew; Sinclair, Craig A.; Wangberg, Sten-Ake; Worrest, Robert C.; Yazar, Seyhan; Young, Antony R.; Zepp, Richard G. (2019)
    Changes in stratospheric ozone and climate over the past 40-plus years have altered the solar ultraviolet (UV) radiation conditions at the Earth's surface. Ozone depletion has also contributed to climate change across the Southern Hemisphere. These changes are interacting in complex ways to affect human health, food and water security, and ecosystem services. Many adverse effects of high UV exposure have been avoided thanks to the Montreal Protocol with its Amendments and Adjustments, which have effectively controlled the production and use of ozone-depleting substances. This international treaty has also played an important role in mitigating climate change. Climate change is modifying UV exposure and affecting how people and ecosystems respond to UV; these effects will become more pronounced in the future. The interactions between stratospheric ozone, climate and UV radiation will therefore shift over time; however, the Montreal Protocol will continue to have far-reaching benefits for human well-being and environmental sustainability.
  • Mõttus, Matti; Stenberg, Pauline; Rautiainen, Miina (AMERICAN GEOPHYSICAL UNION, 2007)
  • Mõttus, Matti; Stenberg, Pauline; Rautiainen, Miina (AMERICAN GEOPHYSICAL UNION, 2007)
  • Lindqvist, Hannakaisa; Martikainen, Julia; Räbinä, Jukka; Penttilä, Antti; Muinonen, Karri (2018)
    Light scattering by particles large compared to the wavelength of incident light is traditionally solved using ray optics which considers absorption inside the particle approximately, along the ray paths. To study the effects rising from this simplification, we have updated the ray-optics code SIRIS to take into account the propagation of light as inhomogeneous plane waves inside an absorbing particle. We investigate the impact of this correction on traditional ray-optics computations in the example case of light scattering by ice crystals through the extended near-infrared (NIR) wavelength regime. In this spectral range, ice changes from nearly transparent to opaque, and therefore provides an interesting test case with direct connection and applicability to atmospheric remote-sensing measurements at NIR wavelengths. We find that the correction for inhomogeneous waves systematically increases the single-scattering albedo throughout the NIR spectrum for both randomly-oriented, column-like hexagonal crystals and ice crystals shaped like Gaussian random spheres. The largest increase in the single-scattering albedo is 0.042 for hexagonal crystals and 0.044 for Gaussian random spheres, both at λ=2.725 µm. Although the effects on the 4  ×  4 scattering-matrix elements are generally small, the largest differences are seen at 2.0 µm and 3.969 µm wavelengths where the correction for inhomogeneous waves affects mostly the backscattering hemisphere of the depolarization-connected P22/P11, P33/P11, and P44/P11. We evaluated the correction for inhomogeneous waves through comparisons against the discrete exterior calculus (DEC) method. We computed scattering by hexagonal ice crystals using the DEC, a traditional ray-optics code (SIRIS3), and a ray-optics code with inhomogeneous waves (SIRIS4). Comparisons of the scattering-matrix elements from SIRIS3 and SIRIS4 against those from the DEC suggest that consideration of the inhomogeneous waves brings the ray-optics solution generally closer to the exact result and, therefore, should be taken into account in scattering by absorbing particles large compared to the wavelength of incident light.
  • Lalonde, K.; Vahatalo, A. V.; Gelinas, Y. (2014)
    Organic carbon (OC) depleted in C-13 is a widely used tracer for terrestrial organic matter (OM) in aquatic systems. Photochemical reactions can, however, change delta C-13 of dissolved organic carbon (DOC) when chromophoric, aromatic-rich terrestrial OC is selectively mineralized. We assessed the robustness of the delta C-13 signature of DOC (delta C-13(DOC)) as a tracer for terrestrial OM by estimating its change during the photobleaching of chromophoric DOM (CDOM) from 10 large rivers. These rivers cumulatively account for approximately one-third of the world's freshwater discharge to the global ocean. Photobleaching of CDOM by simulated solar radiation was associated with the photochemical mineralization of 16 to 43% of the DOC and, by preferentially removing compounds depleted in C-13, caused a 1 to 2.9 parts per thousand enrichment in delta C-13 in the residual DOC. Such solar-radiation-induced photochemical isotopic shift could bias the calculations of terrestrial OM discharge in coastal oceans towards the marine end-member. Shifts in terrestrial delta C-13(DOC) should be taken into account when constraining the terrestrial end-member in global calculation of terrestrially derived DOM in the world ocean.
  • Rodil, Ivan F.; Lastra, Mariano; López, Jesús; Mucha, Ana P.; Fernandes, Joana P.; Fernandes, Sara V.; Olabarria, Celia (2019)
    Sandy beaches, which represent the most common type of land-sea interface, harbor distinctive biotic communities and regulate the flow of energy between marine and terrestrial ecosystems. Accumulations of sea wrack on sandy beaches are of crucial importance for recycling beach nutrients and for regulating trophic connectivity and coastal functioning. We investigated the role of beaches as biogeochemical hotspots by examining the metabolic activity in accumulations of different species of wrack on two exposed beaches affected by different levels of human pressure. Experimental wrack patches provided large amounts of different sedimentary nutrients over time due to remineralization of the algae. Unsurprisingly, the variation in the nutrients present in the beach sediments was related to the species of wrack considered. Macroalgal wrack was metabolically very active and supported high respiration rates represented by intense CO2 fluxes. Importantly, we demonstrated that the wrack metabolic rate differed significantly depending on the algal species considered. Different macrofauna and bacterial assemblages were identified in the different wrack patches and on the different beaches. We suggest that human activities such as beach grooming can modify the wrack-associated communities, thus contributing to the variability in the biogeochemical processes and metabolic rates. Significant changes in the type and amount of wrack deposited on beaches can change fundamental processes related to the marine-terrestrial transfer of nutrients and energy and to the marine-atmospheric transfer of CO2 emissions, with ecological consequences for nearshore environments.
  • Simanjuntak, Christian; Gaiser, Thomas; Ahrends, Hella Ellen; Srivastava, Amit Kumar (2022)
    Climate change impacts on maize production in South Africa, i.e., interannual yield variabilities, are still not well understood. This study is based on a recently released reanalysis of climate observations (AgERA5), i.e., temperature, precipitation, solar radiation, and wind speed data. The study assesses climate change effects by quantifying the trend of agrometeorological indicators, their correlation with maize yield, and analyzing their spatiotemporal patterns using Empirical Orthogonal Function. Thereby, the main agrometeorological factors that affected yield variability for the last 31 years (1990/91-2020/21 growing season) in major maize production provinces, namely Free State, KwaZulu-Natal, Mpumalanga, and North West are identified. Results show that there was a significant positive trend in temperature that averages 0.03-0.04 degrees C per year and 0.02-0.04 degrees C per growing season. There was a decreasing trend in precipitation in Free State with 0.01 mm per year. Solar radiation did not show a significant trend. Wind speed in Free State increased at a rate of 0.01 ms(-1) per growing season. Yield variabilities in Free State, Mpumalanga, and North West show a significant positive correlation (r > 0.43) with agrometeorological variables. Yield in KwaZulu-Natal is not influenced by climate factors. The leading mode (50-80% of total variance) of each agrometeorological variable indicates spatially homogenous pattern across the regions. The dipole patterns of the second and the third mode suggest the variabilities of agrometeorological indicators are linked to South Indian high pressure and the warm Agulhas current. The corresponding principal components were mainly associated with strong climate anomalies which are identified as El Nino and La Nina events.
  • Norros, Veera Maria; Karhu, Elina; Nordén, Jenni; Vähätalo, Anssi Vesa; Ovaskainen, Otso Tapio (2015)
    Assessment of the costs and benefits of dispersal is central to understanding species' life-history strategies as well as explaining and predicting spatial population dynamics in the changing world. While mortality during active movement has received much attention, few have studied the costs of passive movement such as the airborne transport of fungal spores. Here, we examine the potential of extreme environmental conditions to cause dispersal mortality in wood-decay fungi. These fungi play a key role as decomposers and habitat creators in forest ecosystems and the populations of many species have declined due to habitat loss and fragmentation. We measured the effect of simulated solar radiation (including ultraviolet A and B) and freezing at -25 degrees C on the spore germinability of 17 species. Both treatments but especially sunlight markedly reduced spore germinability in most species, and species with thin-walled spores were particularly light sensitive. Extrapolating the species' laboratory responses to natural irradiance conditions, we predict that sunlight is a relevant source of dispersal mortality at least at larger spatial scales. In addition, we found a positive effect of spore size on spore germinability, suggesting a trade-off between dispersal distance and establishment. We conclude that freezing and particularly sunlight can be important sources of dispersal mortality in wood-decay fungi which can make it difficult for some species to colonize isolated habitat patches and habitat edges.
  • Park, Sung-Bin; Knohl, Alexander; Lucas-Moffat, Antje M.; Migliavacca, Mirco; Gerbig, Christoph; Vesala, Timo; Peltola, Oli; Mammarella, Ivan; Kolle, Olaf; Lavric, Jost Valentin; Prokushkin, Anatoly; Heimann, Martin (2018)
    Aerosols produced by wildfires are a common phenomenon in boreal regions. For the Siberian taiga, it is still an open question if the effects of aerosols on atmospheric conditions increase net CO2 uptake or photosynthesis. We investigated the factors controlling forest net ecosystem productivity (NEP) and explored how clouds and smoke modulate radiation as a major factor controlling NEP during fire events in the years 2012 and 2013. To characterize the underlying mechanisms of the NEP response to environmental drivers, Artificial Neural Networks (ANNs) were trained by eddy covariance flux measurements nearby the Zotino Tall Tower Observatory (ZOTTO). Total photosynthetically active radiation, vapour pressure deficit, and diffuse fraction explain at about 54-58% of NEP variability. NEP shows a strong negative sensitivity to VPD, and a small positive to f(dlf). A strong diffuse radiation fertilization effect does not exist at ZOTTO forest due to the combined effects of low light intensity, sparse canopy and low leaf area index. Results suggests that light intensity and canopy structure are important factors of the overall diffuse radiation fertilization effect.
  • Rontu, Laura; Gleeson, Emily; Räisänen, Petri; Nielsen, Kristian Pagh; Savijärvi, Hannu; Sass, Bent Hansen (2017)
    This paper provides an overview of the HLRADIA shortwave (SW) and longwave (LW) broadband radiation schemes used in the HIRLAM numerical weather prediction (NWP) model and available in the HARMONIE-AROME mesoscale NWP model. The advantage of broadband, over spectral, schemes is that they can be called more frequently within the model, without compromising on computational efficiency. In mesoscale models fast interactions between clouds and radiation and the surface and radiation can be of greater importance than accounting for the spectral details of clear-sky radiation; thus calling the routines more frequently can be of greater benefit than the deterioration due to loss of spectral details. Fast but physically based radiation parametrizations are expected to be valuable for high-resolution ensemble forecasting, because as well as the speed of their execution, they may provide realistic physical perturbations. Results from single-column diagnostic experiments based on CIRC benchmark cases and an evaluation of 10 years of radiation output from the FMI operational archive of HIRLAM forecasts indicate that HLRADIA performs sufficiently well with respect to the clear-sky downwelling SW and longwave LWfluxes at the surface. In general, HLRADIA tends to overestimate surface fluxes, with the exception of LW fluxes under cold and dry conditions. The most obvious overestimation of the surface SW flux was seen in the cloudy cases in the 10-year comparison; this bias may be related to using a cloud inhomogeneity correction, which was too large. According to the CIRC comparisons, the outgoing LW and SW fluxes at the top of atmosphere are mostly overestimated by HLRADIA and the net LW flux is underestimated above clouds. The absorption of SW radiation by the atmosphere seems to be underestimated and LW absorption seems to be overestimated. Despite these issues, the overall results are satisfying and work on the improvement of HLRADIA for the use in HARMONIE-AROME NWP system is ongoing. In a HARMONIE-AROME 3-D forecast experiment we have shown that the frequency of the call for the radiation parametrization and choice of the parametrization scheme makes a difference to the surface radiation fluxes and changes the spatial distribution of the vertically integrated cloud cover and precipitation.
  • Helama, Samuli; Arppe, Laura; Uusitalo, Joonas; Holopainen, Jari; Mäkelä, Hanna; Mäkinen, Harri; Mielikäinen, Kari; Nöjd, Pekka; Sutinen, Raimo; Taavitsainen, Jussi-Pekka; Timonen, Mauri; Oinonen, Markku (2018)