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- ItemA phenomenology of new particle formation (NPF) at 13 European sites(Katlenburg-Lindau : European Geosciences Union, 2021) Bousiotis, Dimitrios; Pope, Francis D.; Beddows, David C. S.; Dall'Osto, Manuel; Massling, Andreas; Nøjgaard, Jakob Klenø; Nordstrøm, Claus; Niemi, Jarkko V.; Portin, Harri; Petäjä, Tuukka; Perez, Noemi; Alastuey, Andrés; Querol, Xavier; Kouvarakis, Giorgos; Mihalopoulos, Nikos; Vratolis, Stergios; Eleftheriadis, Konstantinos; Wiedensohler, Alfred; Weinhold, Kay; Merkel, Maik; Tuch, Thomas; Harrison, Roy M.New particle formation (NPF) events occur almost everywhere in the world and can play an important role as a particle source. The frequency and characteristics of NPF events vary spatially, and this variability is yet to be fully understood. In the present study, long-term particle size distribution datasets (minimum of 3 years) from 13 sites of various land uses and climates from across Europe were studied, and NPF events, deriving from secondary formation and not traffic-related nucleation, were extracted and analysed. The frequency of NPF events was consistently found to be higher at rural background sites, while the growth and formation rates of newly formed particles were higher at roadsides (though in many cases differences between the sites were small), underlining the importance of the abundance of condensable compounds of anthropogenic origin found there. The growth rate was higher in summer at all rural background sites studied. The urban background sites presented the highest uncertainty due to greater variability compared to the other two types of site. The origin of incoming air masses and the specific conditions associated with them greatly affect the characteristics of NPF events. In general, cleaner air masses present higher probability for NPF events, while the more polluted ones show higher growth rates. However, different patterns of NPF events were found, even at sites in close proximity (<ĝ€¯200ĝ€¯km), due to the different local conditions at each site. Region-wide events were also studied and were found to be associated with the same conditions as local events, although some variability was found which was associated with the different seasonality of the events at two neighbouring sites. NPF events were responsible for an increase in the number concentration of ultrafine particles of more than 400ĝ€¯% at rural background sites on the day of their occurrence. The degree of enhancement was less at urban sites due to the increased contribution of other sources within the urban environment. It is evident that, while some variables (such as solar radiation intensity, relative humidity, or the concentrations of specific pollutants) appear to have a similar influence on NPF events across all sites, it is impossible to predict the characteristics of NPF events at a site using just these variables, due to the crucial role of local conditions. © Author(s) 2021.
- ItemTerrestrial or marine – indications towards the origin of ice-nucleating particles during melt season in the European Arctic up to 83.7° N(Katlenburg-Lindau : European Geosciences Union, 2021) Hartmann, Markus; Gong, Xianda; Kecorius, Simonas; van Pinxteren, Manuela; Vogl, Teresa; Welti, André; Wex, Heike; Zeppenfeld, Sebastian; Herrmann, Hartmut; Wiedensohler, Alfred; Stratmann, FrankIce-nucleating particles (INPs) initiate the primary ice formation in clouds at temperatures above ca. -38gC and have an impact on precipitation formation, cloud optical properties, and cloud persistence. Despite their roles in both weather and climate, INPs are not well characterized, especially in remote regions such as the Arctic. We present results from a ship-based campaign to the European Arctic during May to July 2017. We deployed a filter sampler and a continuous-flow diffusion chamber for offline and online INP analyses, respectively. We also investigated the ice nucleation properties of samples from different environmental compartments, i.e., the sea surface microlayer (SML), the bulk seawater (BSW), and fog water. Concentrations of INPs (NINP) in the air vary between 2 to 3 orders of magnitudes at any particular temperature and are, except for the temperatures above -10gC and below -32gC, lower than in midlatitudes. In these temperature ranges, INP concentrations are the same or even higher than in the midlatitudes. By heating of the filter samples to 95gC for 1ĝ€¯h, we found a significant reduction in ice nucleation activity, i.e., indications that the INPs active at warmer temperatures are biogenic. At colder temperatures the INP population was likely dominated by mineral dust. The SML was found to be enriched in INPs compared to the BSW in almost all samples. The enrichment factor (EF) varied mostly between 1 and 10, but EFs as high as 94.97 were also observed. Filtration of the seawater samples with 0.2ĝ€¯μm syringe filters led to a significant reduction in ice activity, indicating the INPs are larger and/or are associated with particles larger than 0.2ĝ€¯μm. A closure study showed that aerosolization of SML and/or seawater alone cannot explain the observed airborne NINP unless significant enrichment of INP by a factor of 105 takes place during the transfer from the ocean surface to the atmosphere. In the fog water samples with -3.47gC, we observed the highest freezing onset of any sample. A closure study connecting NINP in fog water and the ambient NINP derived from the filter samples shows good agreement of the concentrations in both compartments, which indicates that INPs in the air are likely all activated into fog droplets during fog events. In a case study, we considered a situation during which the ship was located in the marginal sea ice zone and NINP levels in air and the SML were highest in the temperature range above -10gC. Chlorophyll a measurements by satellite remote sensing point towards the waters in the investigated region being biologically active. Similar slopes in the temperature spectra suggested a connection between the INP populations in the SML and the air. Air mass history had no influence on the observed airborne INP population. Therefore, we conclude that during the case study collected airborne INPs originated from a local biogenic probably marine source. © Author(s) 2021.
- ItemRepresentativeness of European biochar research: part I–field experiments(Vilnius : Technika, 2017) Verheijen, Frank G. A.; Mankasingh, Utra; Penizek, Vit; Panzacchi, Pietro; Glaser, Bruno; Jeffery, Simon; Bastos, Ana Catarina; Tammeorg, Priit; Kern, Jürgen; Zavalloni, Costanza; Zanchettin, Giulia; Sakrabani, RubenA representativeness survey of existing European Biochar field experiments within the Biochar COST Action TD1107 was conducted to gather key information for setting up future experiments and collaborations, and to minimise duplication of efforts amongst European researchers. Woody feedstock biochar, applied without organic or inorganic fertiliser appears over-represented compared to other categories, especially considering the availability of crop residues, manures, and other organic waste streams and the efforts towards achieving a zero waste economy. Fertile arable soils were also over-represented while shallow unfertile soils were under-represented. Many of the latter are likely in agroforestry or forest plantation land use. The most studied theme was crop production. However, other themes that can provide evidence of mechanisms, as well as potential undesired side-effects, were relatively well represented. Biochar use for soil contamination remediation was the least represented theme; further work is needed to identify which specific contaminants, or mixtures of contaminants, have the potential for remediation by different biochars. © 2017 The Author(s) Published by VGTU Press and Informa UK Limited, [trading as Taylor & Francis Group].
- ItemRepresentativeness of European biochar research: part II–pot and laboratory studies(Vilnius : Technika, 2017) Sakrabani, Ruben; Kern, Jürgen; Mankasingh, Utra; Zavalloni, Costanza; Zanchettin, Giulia; Bastos, Ana Catarina; Tammeorg, Priit; Jeffery, Simon; Glaser, Bruno; Verheijen, Frank G. A.Biochar research is extensive and there are many pot and laboratory studies carried out in Europe to investigate the mechanistic understanding that govern its impact on soil processes. A survey was conducted in order to find out how representative these studies under controlled experimental conditions are of actual environmental conditions in Europe and biomass availability and conversion technologies. The survey consisted of various key questions related to types of soil and biochar used, experimental conditions and effects of biochar additions on soil chemical, biological and physical properties. This representativeness study showed that soil texture and soil organic carbon contents used by researchers are well reflected in the current biochar research in Europe (through comparison with published literature), but less so for soil pH and soil type. This study provides scope for future work to complement existing research findings, avoiding unnecessary repetitions and highlighting existing research gaps. © 2017 The Author(s) Published by VGTU Press and Informa UK Limited, [trading as Taylor & Francis Group].
- ItemOccupational health and safety in agriculture – a brief report on organization, legislation and support in selected European countries(Lublin : Institute of Agricultural Medicine, 2021) Jakob, Martina Carola; Santa, Dushica; Holte, Kari Anne; Sikkeland, Inger Johanne; Hilt, Bjorn; Lundqvist, PeterIntroduction and objective: Agriculture and forestry are among the most dangerous professions in Europe, with a high level of accidents affecting the sustainability and viability of the sector. International conventions, EU directives and national legislation build the fundamental basis for prevention. The aim of the study is to describe and categorize national mechanisms of occupational safety and health (OSH) for agricultural workers in Europe, to assess the extent of implementing safety regulation, the body in charge, and to give examples of health and safety initiatives. Material and methods: Results of a questionnaire-survey on basic safety regulations on farms sent by e-mail to the representatives of 30 participating European countries in the context of the Sacurima COST action network (CA 16123) are presented. Due to the complexity, only selected countries are described in this study highlighting the regulative bodies, occupational health services or specific training offers, as well as the complexity of the mechanisms. Results: One of the most serious issues and deficits of EU OSH regulation is the exclusion of self-employed farmers who compose nearly 90% of the farming population. This leads to serious under-reporting of accidents, and because one of the most common measures for the performance of health and safety initiatives are the injury and ill health statistics, better registration systems are urgently needed in almost all countries as a basis for preventive efforts. Conclusions: The results of the study provide a basis for raising awareness about the current OSH systems in Europe, and the importance of developing sector specific OSH strategies. The proposed activities should assist in tackling high accident rates and poor occupational health for self-employed farmers.
- ItemUncertainty of simulated groundwater recharge at different global warming levels: a global-scale multi-model ensemble study(Munich : EGU, 2021) Reinecke, Robert; Müller Schmied, Hannes; Trautmann, Tim; Andersen, Lauren Seaby; Burek, Peter; Flörke, Martina; Gosling, Simon N.; Grillakis, Manolis; Hanasaki, Naota; Koutroulis, Aristeidis; Pokhrel, Yadu; Thiery, Wim; Wada, Yoshihide; Yusuke, Satoh; Döll, PetraBillions of people rely on groundwater as being an accessible source of drinking water and for irrigation, especially in times of drought. Its importance will likely increase with a changing climate. It is still unclear, however, how climate change will impact groundwater systems globally and, thus, the availability of this vital resource. Groundwater recharge is an important indicator for groundwater availability, but it is a water flux that is difficult to estimate as uncertainties in the water balance accumulate, leading to possibly large errors in particular in dry regions. This study investigates uncertainties in groundwater recharge projections using a multi-model ensemble of eight global hydrological models (GHMs) that are driven by the bias-adjusted output of four global circulation models (GCMs). Pre-industrial and current groundwater recharge values are compared with recharge for different global warming (GW) levels as a result of three representative concentration pathways (RCPs). Results suggest that projected changes strongly vary among the different GHM–GCM combinations, and statistically significant changes are only computed for a few regions of the world. Statistically significant GWR increases are projected for northern Europe and some parts of the Arctic, East Africa, and India. Statistically significant decreases are simulated in southern Chile, parts of Brazil, central USA, the Mediterranean, and southeastern China. In some regions, reversals of groundwater recharge trends can be observed with global warming. Because most GHMs do not simulate the impact of changing atmospheric CO2 and climate on vegetation and, thus, evapotranspiration, we investigate how estimated changes in GWR are affected by the inclusion of these processes. In some regions, inclusion leads to differences in groundwater recharge changes of up to 100 mm per year. Most GHMs with active vegetation simulate less severe decreases in groundwater recharge than GHMs without active vegetation and, in some regions, even increases instead of decreases are simulated. However, in regions where GCMs predict decreases in precipitation and where groundwater availability is the most important, model agreement among GHMs with active vegetation is the lowest. Overall, large uncertainties in the model outcomes suggest that additional research on simulating groundwater processes in GHMs is necessary.
- ItemA European aerosol phenomenology -4: Harmonized concentrations of carbonaceous aerosol at 10 regional background sites across Europe(Amsterdam [u.a.] : Elsevier Science, 2016) Cavalli, F.; Alastuey, A.; Areskoug, H.; Ceburnis, D.; Čech, J.; Genberg, J.; Harrison, R.M.; Jaffrezo, J.L.; Kiss, G.; Laj, P.; Mihalopoulos, N.; Perez, N.; Quincey, P.; Schwarz, J.; Sellegri, K.; Spindler, G.; Swietlicki, E.; Theodosi, C.; Yttri, K.E.; Aas, W.; Putaud, J.P.Although particulate organic and elemental carbon (OC and EC) are important constituents of the suspended atmospheric particulate matter (PM), measurements of OC and EC are much less common and more uncertain than measurements of e.g. the ionic components of PM. In the framework of atmospheric research infrastructures supported by the European Union, actions have been undertaken to determine and mitigate sampling artefacts, and assess the comparability of OC and EC data obtained in a network of 10 atmospheric observatories across Europe. Positive sampling artefacts (from 0.4 to 2.8 μg C/m3) and analytical discrepancies (between −50% and +40% for the EC/TC ratio) have been taken into account to generate a robust data set, from which we established the phenomenology of carbonaceous aerosols at regional background sites in Europe. Across the network, TC and EC annual average concentrations range from 0.4 to 9 μg C/m3, and from 0.1 to 2 μg C/m3, respectively. TC/PM10 annual mean ratios range from 0.11 at a Mediterranean site to 0.34 at the most polluted continental site, and TC/PM2.5 ratios are slightly greater at all sites (0.15–0.42). EC/TC annual mean ratios range from 0.10 to 0.22, and do not depend much on PM concentration levels, especially in winter. Seasonal variations in PM and TC concentrations, and in TC/PM and EC/TC ratios, differ across the network, which can be explained by seasonal changes in PM source contributions at some sites.
- ItemThe energy and carbon inequality corridor for a 1.5 °C compatible and just Europe(Bristol : IOP Publ., 2021-6-15) Jaccard, Ingram S; Pichler, Peter-Paul; Többen, Johannes; Weisz, HelgaThe call for a decent life for all within planetary limits poses a dual challenge: provide all people with the essential resources needed to live well and, collectively, not exceed the source and sink capacity of the biosphere to sustain human societies. We examine the corridor of possible distributions of household energy and carbon footprints that satisfy both minimum energy use for a decent life and available energy supply compatible with the 1.5 °C target in 2050. We estimated household energy and carbon footprints for expenditure deciles for 28 European countries in 2015 by combining data from national household budget surveys with the environmentally-extended multi-regional input–output model EXIOBASE. We found a top-to-bottom decile ratio (90:10) of 7.2 for expenditure, 3.1 for net energy and 2.6 for carbon. The lower inequality of energy and carbon footprints is largely attributable to inefficient energy and heating technologies in the lower deciles (mostly Eastern Europe). Adopting best technology across Europe would save 11 EJ of net energy annually, but increase environmental footprint inequality. With such inequality, both targets can only be met through the use of CCS, large efficiency improvements, and an extremely low minimum final energy use of 28 GJ per adult equivalent. Assuming a more realistic minimum energy use of about 55 GJ ae−1 and no CCS deployment, the 1.5 °C target can only be achieved at near full equality. We conclude that achieving both stated goals is an immense and widely underestimated challenge, the successful management of which requires far greater room for maneuver in monetary and fiscal terms than is reflected in the current European political discourse.
- ItemRecurrent Governance Challenges in the Implementation and Alignment of Flood Risk Management Strategies: a Review(Dordrecht [u.a.] : Springer Science + Business Media B.V, 2016) Dieperink, C.; Hegger, D.L.T; Bakker, M.H.N.; Kundzewicz, Z.W.; Green, C.; Driessen, P.P.J.In Europe increasing flood risks challenge societies to diversify their Flood Risk Management Strategies (FRMSs). Such a diversification implies that actors not only focus on flood defence, but also and simultaneously on flood risk prevention, mitigation, preparation and recovery. There is much literature on the implementation of specific strategies and measures as well as on flood risk governance more generally. What is lacking, though, is a clear overview of the complex set of governance challenges which may result from a diversification and alignment of FRM strategies. This paper aims to address this knowledge gap. It elaborates on potential processes and mechanisms for coordinating the activities and capacities of actors that are involved on different levels and in different sectors of flood risk governance, both concerning the implementation of individual strategies and the coordination of the overall set of strategies. It identifies eight overall coordination mechanisms that have proven to be useful in this respect.