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  • 351.
    Donnelly, Chantal
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    Yang, Wei
    SMHI, Forskningsavdelningen, Hydrologi.
    Dahne, Joel
    SMHI, Affärsverksamhet.
    River discharge to the Baltic Sea in a future climate2014Inngår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 122, nr 1-2, s. 157-170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study reports on new projections of discharge to the Baltic Sea given possible realisations of future climate and uncertainties regarding these projections. A high-resolution, pan-Baltic application of the Hydrological Predictions for the Environment (HYPE) model was used to make transient simulations of discharge to the Baltic Sea for a mini-ensemble of climate projections representing two high emissions scenarios. The biases in precipitation and temperature adherent to climate models were adjusted using a Distribution Based Scaling (DBS) approach. As well as the climate projection uncertainty, this study considers uncertainties in the bias-correction and hydrological modelling. While the results indicate that the cumulative discharge to the Baltic Sea for 2071 to 2100, as compared to 1971 to 2000, is likely to increase, the uncertainties quantified from the hydrological model and the bias-correction method show that even with a state-of-the-art methodology, the combined uncertainties from the climate model, bias-correction and impact model make it difficult to draw conclusions about the magnitude of change. It is therefore urged that as well as climate model and scenario uncertainty, the uncertainties in the bias-correction methodology and the impact model are also taken into account when conducting climate change impact studies.

  • 352. Doos, K
    et al.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Doescher, Ralf
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    The Baltic haline conveyor belt or the overturning circulation and mixing in the Baltic2004Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 33, nr 4-5, s. 261-266Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A study of the water-mass circulation of the Baltic has been undertaken by making use of a three dimensional Baltic Sea model simulation. The saline water from the North Atlantic is traced through the Danish Sounds into the Baltic where it upwells and mixes with the fresh water inflow from the rivers forming a Baltic haline conveyor belt. The mixing of the saline water from the Great Belt and Oresund with the fresh water is investigated making use of overturning stream functions and Lagrangian trajectories. The overturning stream function was calculated as a function of four different vertical coordinates (depth, salinity, temperature and density) in order to understand the path of the water and where it upwells and mixes. Evidence of a fictive depth overturning cell similar to the Deacon Cell in the Southern Ocean was found in the Baltic proper corresponding to the gyre circulation around Gotland, which vanishes when the overturning stream function is projected on density layers. A Lagrangian trajectory study was performed to obtain a better view of the circulation and mixing of the saline and fresh waters. The residence time of the water masses in the Baltic is calculated to be 26-29 years and the Lagrangian dispersion reaches basin saturation after 5 years.

  • 353. Dosio, Alessandro
    et al.
    Mentaschi, Lorenzo
    Fischer, Erich M.
    Wyser, Klaus
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Extreme heat waves under 1.5 degrees C and 2 degrees C global warming2018Inngår i: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 13, nr 5, artikkel-id 054006Artikkel i tidsskrift (Fagfellevurdert)
  • 354. Dufton, David
    et al.
    Haase, Günther
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Johnson, Daniel
    Vulpiani, Gianfranco
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    MONITORING THE ONGOING UPGRADE OF THE SWEDISH WEATHER RADAR NETWORK2018Inngår i: 10th European Conference on Radar in Meteorology and Hydrology (ERAD 2018) : 1-6 July 2018, Ede-Wageningen, The Netherlands / [ed] Vos, Lotte de; Leijnse, Hidde; Uijlenhoet, Remko, 2018, s. 249-250, artikkel-id 6.16Konferansepaper (Annet vitenskapelig)
  • 355.
    Dybbroe, Adam
    et al.
    SMHI, Samhälle och säkerhet.
    Karlsson, Karl-Göran
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Thoss, Anke
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    NWCSAF AVHRR cloud detection and analysis using dynamic thresholds and radiative transfer modeling. Part I: Algorithm description2005Inngår i: Journal of applied meteorology (1988), ISSN 0894-8763, E-ISSN 1520-0450, Vol. 44, nr 1, s. 39-54Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    New methods and software for cloud detection and classification at high and midlatitudes using Advanced Very High Resolution Radiometer (AVHRR) data are developed for use in a wide range of meteorological, climatological, land surface, and oceanic applications within the Satellite Application Facilities (SAFs) of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT), including the SAF for Nowcasting and Very Short Range Forecasting Applications (NWCSAF) project. The cloud mask employs smoothly varying (dynamic) thresholds that separate fully cloudy or cloud-contaminated fields of view from cloud-free conditions. Thresholds are adapted to the actual state of the atmosphere and surface and the sun-satellite viewing geometry using cloud-free radiative transfer model simulations. Both the cloud masking and the cloud-type classification are done using sequences of grouped threshold tests that employ both spectral and textural features. The cloud-type classification divides the cloudy pixels into 10 different categories: 5 opaque cloud types, 4 semitransparent clouds, and 1 subpixel cloud category. The threshold method is fuzzy in the sense that the distances in feature space to the thresholds are stored and are used to determine whether to stop or to continue testing. They are also used as a quality indicator of the final output. The atmospheric state should preferably be taken from a short-range NWP model, but the algorithms can also run with climatological fields as input.

  • 356.
    Dybbroe, Adam
    et al.
    SMHI, Samhälle och säkerhet.
    Karlsson, Karl-Göran
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Thoss, Anke
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    NWCSAF AVHRR cloud detection and analysis using dynamic thresholds and radiative transfer modeling. Part II: Tuning and validation2005Inngår i: Journal of applied meteorology (1988), ISSN 0894-8763, E-ISSN 1520-0450, Vol. 44, nr 1, s. 55-71Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Algorithms for cloud detection (cloud mask) and classification (cloud type) at high and midlatitudes using data from the Advanced Very High Resolution Radiometer (AVHRR) on board the current NOAA satellites and future polar Meteorological and Operational Weather Satellites (METOP) of the European Organisation for the Exploitation of Meteorological Satellites have been extensively validated over northern Europe and the adjacent seas. The algorithms have been described in detail in Part I and are based on a multispectral grouped threshold approach, making use of cloud-free radiative transfer model simulations. The thresholds applied in the algorithms have been validated and tuned using a database interactively built up over more than 1 yr of data from NOAA-12, -14, and -15 by experienced nephanalysts. The database contains almost 4000 rectangular (in the image data)-sized targets (typically with sides around 10 pixels), with satellite data collocated in time and space with atmospheric data from a short-range NWP forecast model, land cover characterization, elevation data, and a label identifying the given cloud or surface type as interpreted by the nephanalyst. For independent and objective validation, a large dataset of nearly 3 yr of collocated surface synoptic observation (Synop) reports, AVHRR data, and NWP model output over northern and central Europe have been collected. Furthermore, weather radar data were used to check the consistency of the cloud type. The cloud mask performs best over daytime sea and worst at twilight and night over land. As compared with Synop, the cloud cover is overestimated during night (except for completely overcast situations) and is underestimated at twilight. The algorithms have been compared with the more empirically based Swedish Meteorological and Hydrological Institute (SMHI) Cloud Analysis Model Using Digital AVHRR Data (SCANDIA), operationally run at SMHI since 1989, and results show that performance has improved significantly.

  • 357. Eckhardt, S.
    et al.
    Quennehen, B.
    Olivie, D. J. L.
    Berntsen, T. K.
    Cherian, R.
    Christensen, J. H.
    Collins, W.
    Crepinsek, S.
    Daskalakis, N.
    Flanner, M.
    Herber, A.
    Heyes, C.
    Hodnebrog, O.
    Huang, L.
    Kanakidou, M.
    Klimont, Z.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Law, K. S.
    Lund, M. T.
    Mahmood, R.
    Massling, A.
    Myriokefalitakis, S.
    Nielsen, I. E.
    Nojgaard, J. K.
    Quaas, J.
    Quinn, P. K.
    Raut, J. -C
    Rumbold, S. T.
    Schulz, M.
    Sharma, S.
    Skeie, R. B.
    Skov, H.
    Uttal, T.
    von Salzen, K.
    Stohl, A.
    Current model capabilities for simulating black carbon and sulfate concentrations in the Arctic atmosphere: a multi-model evaluation using a comprehensive measurement data set2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 16, s. 9413-9433Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concentrations of sulfate, black carbon (BC) and other aerosols in the Arctic are characterized by high values in late winter and spring (so-called Arctic Haze) and low values in summer. Models have long been struggling to capture this seasonality and especially the high concentrations associated with Arctic Haze. In this study, we evaluate sulfate and BC concentrations from eleven different models driven with the same emission inventory against a comprehensive pan-Arctic measurement data set over a time period of 2 years (2008-2009). The set of models consisted of one Lagrangian particle dispersion model, four chemistry transport models (CTMs), one atmospheric chemistry-weather forecast model and five chemistry climate models (CCMs), of which two were nudged to meteorological analyses and three were running freely. The measurement data set consisted of surface measurements of equivalent BC (eBC) from five stations (Alert, Barrow, Pallas, Tiksi and Zeppelin), elemental carbon (EC) from Station Nord and Alert and aircraft measurements of refractory BC (rBC) from six different campaigns. We find that the models generally captured the measured eBC or rBC and sulfate concentrations quite well, compared to previous comparisons. However, the aerosol seasonality at the surface is still too weak in most models. Concentrations of eBC and sulfate averaged over three surface sites are underestimated in winter/spring in all but one model (model means for January-March underestimated by 59 and 37% for BC and sulfate, respectively), whereas concentrations in summer are overestimated in the model mean (by 88 and 44% for July-September), but with overestimates as well as underestimates present in individual models. The most pronounced eBC underestimates, not included in the above multi-site average, are found for the station Tiksi in Siberia where the measured annual mean eBC concentration is 3 times higher than the average annual mean for all other stations. This suggests an underestimate of BC sources in Russia in the emission inventory used. Based on the campaign data, biomass burning was identified as another cause of the modeling problems. For sulfate, very large differences were found in the model ensemble, with an apparent anti-correlation between modeled surface concentrations and total atmospheric columns. There is a strong correlation between observed sulfate and eBC concentrations with consistent sulfate/eBC slopes found for all Arctic stations, indicating that the sources contributing to sulfate and BC are similar throughout the Arctic and that the aerosols are internally mixed and undergo similar removal. However, only three models reproduced this finding, whereas sulfate and BC are weakly correlated in the other models. Overall, no class of models (e.g., CTMs, CCMs) performed better than the others and differences are independent of model resolution.

  • 358.
    Edman, Moa
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Eilola, Kari
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Wåhlstrom, Irene
    SMHI, Forskningsavdelningen, Oceanografi.
    Arneborg, Lars
    SMHI, Forskningsavdelningen, Oceanografi.
    Nutrient Retention in the Swedish Coastal Zone2018Inngår i: Frontiers in Marine Science, E-ISSN 2296-7745, Vol. 5, artikkel-id UNSP 415Artikkel i tidsskrift (Fagfellevurdert)
  • 359. Eero, Margit
    et al.
    Andersson, Helén
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    MacKenzie, Brian R.
    Has eutrophication promoted forage fish production in the Baltic Sea?2016Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 45, nr 6, s. 649-660Artikkel i tidsskrift (Fagfellevurdert)
  • 360. Eggert, B.
    et al.
    Berg, Peter
    SMHI, Forskningsavdelningen, Hydrologi.
    Haerter, J. O.
    Jacob, D.
    Moseley, C.
    Temporal and spatial scaling impacts on extreme precipitation2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 10, s. 5957-5971Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Convective and stratiform precipitation events have fundamentally different physical causes. Using a radar composite over Germany, this study separates these precipitation types and compares extremes at different spatial and temporal scales, ranging from 1 to 50 km and 5 min to 6 h, respectively. Four main objectives are addressed. First, we investigate extreme precipitation intensities for convective and stratiform precipitation events at different spatial and temporal resolutions to identify type-dependent space and time reduction factors and to analyze regional and seasonal differences over Germany. We find strong differences between the types, with up to 30% higher reduction factors for convective compared to stratiform extremes, exceeding all other observed seasonal and regional differences within one type. Second, we investigate how the differences in reduction factors affect the contribution of each type to extreme events as a whole, again dependent on the scale and the threshold chosen. A clear shift occurs towards more convective extremes at higher resolution or higher percentiles. For horizontal resolutions of current climate model simulations, i.e., similar to 10 km, the temporal resolution of the data as well as the chosen threshold have profound influence on which type of extreme will be statistically dominant. Third, we compare the ratio of area to duration reduction factor for convective and stratiform events and find that convective events have lower effective advection velocities than stratiform events and are therefore more strongly affected by spatial than by temporal aggregation. Finally, we discuss the entire precipitation distribution regarding data aggregation and identify matching pairs of temporal and spatial resolutions where similar distributions are observed. The information is useful for planning observational networks or storing model data at different temporal and spatial scales.

  • 361.
    Eigenheer, Andrea
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Quadfasel, D
    Seasonal variability of the Bay of Bengal circulation inferred from TOPEX/Poseidon altimetry2000Inngår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 105, nr C2, s. 3243-3252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The circulation in the interior of the Bay of Bengal and of its western boundary current, the East Indian Coastal Current, is inferred from historical ship drift data and from TOPEX/Poseidon altimeter data. The boundary current shows a strong seasonal variability with reversals twice per year that lead the reversal of the local monsoon wind field by several months. On the basis of model simulations it has been suggested that this unusual behavior can be explained by the influence of remotely forced planetary waves. Our data analysis confirms and refines this view by showing the role of topography in the northern bay. We also give an estimate of the relative importance of the different contributions.

  • 362.
    Eilola, Kari
    SMHI, Forskningsavdelningen, Oceanografi.
    On the dynamics of organic nutrients, nitrogen and phosphorus, in the Baltic Sea2009Rapport (Annet vitenskapelig)
    Abstract [en]

    In this report we study the dynamics of organic nutrients, nitrogen and phosphorus, in the Baltic Sea. The results indicate that much of the characteristics of the surface layer dynamics of organic nutrients can be described by the Redfield ratio especially in the Baltic proper. There is however deviations from the Redfield ratio that are discussed and needs to be further investigated. The seasonal variations at all investigated stations indicate that the increase and decrease of the organic phosphorus and nitrogen concentrations in spring and autumn takes place with stoichiometric values different from the Redfield ratio. It is also found that organic phosphorus concentrations start to decrease earlier in summer than organic nitrogen that may continue to increase during summer and early autumn. There is a clear trend with decreasing DIN:DIP ratios in late winter at the Gotland Deep during the period 1995-2008 while there is an improved correlation of the Redfield model during the later part of the period when we have extremely low DIN:DIP ratios. Also the results from the Bothnian bay show that the variability of organic matter is fairly well described by the Redfield model despite the extremely high late winter N:P ratios observed in this region. Hence, the seasonal variability of organic matter seems to be rather independent of the ratio of inorganic nutrients. The variability of the inorganic N to P ratios in late winter and early spring across the Baltic Sea is much larger than seen from the variability of the organic matter. This suggests that other sources than DIN and DIP as sources for new nutrients in spring are used. This is true both in the Baltic proper, where an additional nitrogen source for organic matter production in spring is needed besides inorganic nitrogen, and in the Bothnian Bay, where an additional phosphorus source is needed. Nitrogen fixation by cyanobacteria that grow later in the summer in the southern Baltic Sea can not explain the additional nitrogen source needed in early spring. Future model experiments may reveal more information about the dynamics of organic matter in the Baltic Sea.

  • 363.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Andersen, Per
    Nautsvoll, Lars Johan
    Karlson, Bengt
    SMHI, Forskningsavdelningen, Oceanografi.
    Modelling the dynamics of harmful blooms of Chattonella sp. in the Skagerrak and the Kattegat2011Inngår i: ICES CM 2006/E:12, 2011Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The presentation shows observations, satellite images and model results describing the growth and spreading of Chattonella sp. flagellates in the Skagerrak and the Kattegat. Chattonella sp. is a harmful alga that may cause fish kills due to damage of the gills. Calm weather, stable water column stratification, and low turbulence may facilitate the onset of a Chattonella bloom. Results from the three-dimensional hydrodynamical model HIROMB (High Resolution Operational Model for the Baltic Sea) are used as forcing of a transport model that computes vertical and horizontal transports of chemical and biological compounds. A modified version of the Swedish Coastal and Ocean Biogeochemical model (SCOBI) is used to describe the temporal evolution of the phytoplankton spring blooms in the year 2001 when Chattonella was abundant and 2002 when only small amounts of Chattonella were observed. A comparison with satellite images and cell counts indicates that the model captures the main transport patterns of phytoplankton in the surface layers of the offshore areas. The Chattonella bloom of the model starts in the quite shallow parts of the western Kattegat and in the stratified coastal areas of the northern Skagerrak. The coastal waters near the river Göta Älv of Sweden also indicate a tendency of an increased occurrence of Chattonella. Chattonella is observed in the model during both years but the occurrence of Chattonella is more significant in the year 2001 than in 2002.

  • 364.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Dieterich, Christian
    SMHI, Forskningsavdelningen, Oceanografi.
    Fransner, Filippa
    Höglund, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Modeling Nutrient Transports and Exchanges of Nutrients Between Shallow Regions and the Open Baltic Sea in Present and Future Climate2012Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 41, nr 6, s. 586-599Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We quantified horizontal transport patterns and the net exchange of nutrients between shallow regions and the open sea in the Baltic proper. A coupled biogeochemical-physical circulation model was used for transient simulations 1961-2100. The model was driven by regional downscaling of the IPCC climate change scenario A1B from two global General Circulation Models in combination with two nutrient load scenarios. Modeled nutrient transports followed mainly the large-scale internal water circulation and showed only small circulation changes in the future projections. The internal nutrient cycling and exchanges between shallow and deeper waters became intensified, and the internal removal of phosphorus became weaker in the warmer future climate. These effects counteracted the impact from nutrient load reductions according to the Baltic Sea Action Plan. The net effect of climate change and nutrient reductions was an increased net import of dissolved inorganic phosphorus to shallow areas in the Baltic proper.

  • 365.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Edman, Moa
    SMHI, Forskningsavdelningen, Oceanografi.
    Eremina, Tatjana 
    Russian State Hydrometeorological University, Sankt-Petersburg, Russia.
    Larsen, Janus
    Aarhus University, Roskilde, Denmark.
    Janas, Urszula 
    Institute of Oceanography, Gdansk University, Poland.
    Timmermann, Karen 
    Aarhus University, Roskilde, Denmark.
    Tedesco, Letizia 
    Finnish Environment Institute, Helsinki, Finland.
    Voloshchuk, Ekaterina 
    Russian State Hydrometeorological University, Sankt-Petersburg, Russia.
    Model set-up at COCOA study sites2015Rapport (Annet vitenskapelig)
    Abstract [en]

    COCOA will investigate physical, biogeochemical and biological processes in a combined and coordinated fashion to improve the understanding of the interaction of these processes on the removal of nutrients along the land-sea interface. The results from the project will be used to estimate nutrient retention capacity in the coastal zone of the entire Baltic Sea coast. An ensemble of biogeochemical models will be used in combination with field studies at seven different coastal study sites around the Baltic Sea. The present report is a deliverable of COCOA work package 5 (WP5). Within the objective of WP5 process understanding and process descriptions will be improved in state-of-the-art biogeochemical models of the Baltic Sea coastal zone. This report presents brief information about the models available for the COCOA project and defines the needed input to the models that will be set-up at several learning sites. The aim is to perform ensemble modelling at several sites, using at least two different models at each site. A pilot study to estimate nutrient retention capacity in the Stockholm Archipelago with the existing Swedish model system is ongoing and first results are presented and the concept of nutrient retention is briefly discussed. The existing models for different learning sites presented in the report are; 1) The Swedish model system SCM (Öre river estuary and the Stockholm archipelago) - A multi-box-model approach 2) The Danish model system FLEXSEM (Roskilde fjord) - A combined box-model and 3-D model approach 3) The Finnish model system ESIM-BFMSI (Tvärminne Archipelago) - A 1D box-model approach 4) The Polish model system M3D UG/ProDeMo (Puck Bay) - A 3-D model approach. Operational model. 5) The Lithuanian model system SYFEM/AQUABC (Curonian Lagoon) - A combined box-model and 3-D model approach 6) The Swedish open Baltic model system RCO-SCOBI (for the open Baltic Sea and the Gulf of Gdansk/Vistula). - A 3-D model approach In addition a biogeochemical model (Boudreau, 1996) for the Gulf of Finland (Russian State Hydrometeorological University model) is used to study the quantitative effect of Marenzelleria on the Gulf of Finland ecosystem. Process studies at selected sites will be performed with a reactive transport model developed at Utrecht University. Focus will be on the role of iron and phosphorus cycling. Process studies with the Danish model system will support the development of new parameterizations of nutrient fluxes taking benthic habitat into account. The new parameterizations of the nutrient fluxes will in addition also be implemented into SCM and the models will be used to estimate nutrient fluxes, retention times and the filter capacity of the coastal zones. The In Kind contributions from previously (in the literature) well described open Baltic Sea models RCO-SCOBI, BALTSEM, ERGOM and SPBEM that will be used for the description of open sea conditions are also briefly mentioned in the report with references to the relevant literature. 6) The Swedish open Baltic model system RCO-SCOBI (for the open Baltic Sea and the Gulf of Gdansk/Vistula). - A 3-D model approach In addition a biogeochemical model (Boudreau, 1996) for the Gulf of Finland (Russian State Hydrometeorological University model) is used to study the quantitative effect of Marenzelleria on the Gulf of Finland ecosystem. Process studies at selected sites will be performed with a reactive transport model developed at Utrecht University. Focus will be on the role of iron and phosphorus cycling. Process studies with the Danish model system will support the development of new parameterizations of nutrient fluxes taking benthic habitat into account. The new parameterizations of the nutrient fluxes will in addition also be implemented into SCM and the models will be used to estimate nutrient fluxes, retention times and the filter capacity of the coastal zones. The In Kind contributions from previously (in the literature) well described open Baltic Sea models RCO-SCOBI, BALTSEM, ERGOM and SPBEM that will be used for the description of open sea conditions are also briefly mentioned in the report with references to the relevant literature.

  • 366.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Impact of saltwater inflows on phosphorus cycling and eutrophication in the Baltic Sea: a 3D model study2014Inngår i: Tellus. Series A, Dynamic meteorology and oceanography, ISSN 0280-6495, E-ISSN 1600-0870, Vol. 66, artikkel-id 23985Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The impact of dense saltwater inflows on the phosphorus dynamics in the Baltic Sea is studied from tracer experiments with a three-dimensional physical model. Model simulations showed that the coasts of the North West Gotland Basin and the Gulf of Finland, the Estonian coast in the East Gotland Basin are regions where tracers from below the halocline are primarily lifted up above the halocline. After 1 yr tracers are accumulated at the surface along the Swedish east coast and at the western and southern sides of Gotland. Elevated concentrations are also found east and southeast of Gotland, in the northern Bornholm Basin and in the central parts of the East Gotland Basin. The annual supplies of phosphorus from the deeper waters to the productive surface layers are estimated to be of the same order of magnitude as the waterborne inputs of phosphorus to the entire Baltic Sea. The model results suggest that regionally the impact of these nutrients may be quite large, and the largest regional increases in surface concentrations are found after large inflows. However, the overall direct impact of major Baltic inflows on the annual uplift of nutrients from below the halocline to the surface waters is small because vertical transports are comparably large also during periods without major inflows. Our model results suggest that phosphorus released from the sediments between 60 and 100 m depth in the East Gotland Basin contributes to the eutrophication, especially in the coastal regions of the eastern Baltic Proper.

  • 367.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Gustafson, B.G.
    Baltic Nest Institute, Resilience Centre, Stockholm University, Sweden.
    Hordoir, Robinson
    SMHI, Forskningsavdelningen, Oceanografi.
    Höglund, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    Kuznetsov, I.
    Baltic Sea Research Institute Warnemünde, Germany.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Savchuk, O.P.
    Baltic Nest Institute, Resilience Centre, Stockholm University, Sweden.
    Quality assessment of state-of-the-art coupled physical-biogeochemical models in hind cast simulations 1970-20052010Rapport (Annet vitenskapelig)
    Abstract [en]

    The objectives of the project ECOSUPPORT (Advanced modeling tool for scenarios of the Baltic Sea ECOsystem to SUPPORT decision making) are to calculate the combined effects of changing climate and changing human activity (e.g. changing nutrient loads) on the Baltic Sea ecosystem. Three state-of-the-art coupled physical-biogeochemical models (BALTSEM, ERGOM, and RCO-SCOBI) are used to calculate changing concentrations of nitrate, ammonium, phosphate, diatoms, flagellates, cyanobacteria, zooplankton, detritus, and oxygen in the Baltic Sea. The models are structurally different in that ERGOM and RCO-SCOBI are 3D circulation models with uniform high horizontal resolution while BALTSEM resolves the Baltic Sea spatially in 13 sub-basins. This report summarises first results of the quality assessment and model intercomparison within ECOSUPPORT. Results from hindcast simulations are compared with observations for the period 1970-2005. We found that all three investigated models are able to reproduce the observed variability of biogeochemical cycles well. Uncertainties are primarily related to differences in the bioavailable fractions of nutrient loadings from land and parameterizations of key processes like sediment fluxes that are presently not well known. Avsikten med projektet ECOSUPPORT (Advanced modeling tool for scenarios of the Baltic Sea ECOsystem to SUPPORT decision making) är att undersöka hur klimatförändringar tillsammans med mänsklig aktivitet (förändrad närsaltstillförsel) påverkar Östersjöns ekosystem. Tre kopplade fysiska-biogeokemiska modeller (BALTSEM, ERGOM, and RCO-SCOBI) används för att beräkna hur koncentrationer av nitrat, ammonium, fosfat, diatoméer, flagellater, cyanobakterier, djurplankton, detritus och löst syrgas i Östersjön förändras. Modellerna skiljer sig strukturellt åt genom att ERGOM och RCO-SCOBI är tredimensionella modeller med hög horisontell upplösning medan BALTSEM delar upp östersjön rumsligt i 13 delbassänger. Denna rapport sammanfattar resultaten från en första modelljämförelse och kvalitetsbedömning där modellresultat för tidsperioden 1970-2005 jämförs med observationer från samma period. Alla tre modellerna visar att de kan återskapa den observerade biogeokemiska variabiliteten väl. Osäkerheter är huvudsakligen relaterade till skillnader i andelen av näringstillförseln från land som antas vara biologiskt tillgänglig och till beskrivningarna av viktiga processer, som t.ex. flöden från sedimenten, där kunskapen för närvarande är bristfällig.

  • 368.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Gustafson, B.G
    Kuznetsov, Ivan
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Neumann, T.
    Savchuk, O. P.
    Evaluation of biogeochemical cycles in an ensemble of three state-of-the-art numerical models of the Baltic Sea2011Inngår i: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 88, nr 2, s. 267-284Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three state-of-the-art coupled physical–biogeochemical models, the BAltic sea Long-Term large-Scale Eutrophication Model (BALTSEM), the Ecological Regional Ocean Model (ERGOM), and the Swedish Coastal and Ocean Biogeochemical model coupled to the Rossby Centre Ocean circulation model (RCO–SCOBI), are used to calculate changing nutrient and oxygen dynamics in the Baltic Sea. The models are different in that ERGOM and RCO–SCOBI are three-dimensional (3D) circulation models while BALTSEM resolves the Baltic Sea into 13 dynamically interconnected and horizontally integrated sub-basins. The aim is to assess the simulated long-term dynamics and to discuss the response of the coupled physical–biogeochemical models to changing physical conditions and nutrient loadings during the period 1970–2005. We compared the long-term seasonal and annual statistics of inorganic nitrogen, phosphorus, and oxygen from hindcast simulations with those estimated from observations. We also studied the extension of hypoxic bottom areas covered by waters with O2 b2 ml O2 l −1 and cod reproductive volumes comprising waters with salinity N11 and O2 N2 ml O2 l −1 . The models reproduce much of the nutrient biogeochemical cycling in the Baltic proper. However, biases are larger in the Bothnian Sea and Bothnian Bay. No model shows outstanding performance in all aspects but instead the ensemble mean results are better than or as good as the results of any of the individual models. Uncertainties are primarily related to differences in the bioavailable fractions of nutrient loadings from land and parameterizations of key processes like sediment fluxes that are presently not well known. Also the uncertainty related to the initialization of the models in the early 1960s influence the modeled biogeochemical cycles during the investigated period. ©

  • 369.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Hansen, J.
    National Environmental Research Institute, Aarhus University, Denmark.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Myrberg, K.
    Finnish Environment Institute, Finland Nordic.
    Ryabchenko, V.A.
    St. Petersburg Branch, P.P.Shirshov Institute of Oceanology, Russia.
    Skogen, Morten
    Institute of Marine Research, Norway.
    Eutrophication Status Report of the North Sea, Skagerrak, Kattegat and the Baltic Sea: A model study Years 2001-20052011Rapport (Annet vitenskapelig)
    Abstract [sv]

    Följande statusrapport för Nordsjön, Skagerrak, Kattegatt och Östersjön har genomförts av SMHI Sverige, IMR Norge, NERI Danmark, SPBIO Ryssland, och SYKE Finland som del av projektet “A Baltic and NORth sea Model eutrophication Assessment in a future cLimate” (ABNORMAL), vilket finansierats av the Nordic Council of Ministers’ Sea and Air Group (NMR-HLG). De tidigare NMR-HLG projekten NO COMMENTS och BANSAI fokuserades på etablering och underhållsstöd till operationella modeller samt utvecklingen av metoder för deras användning till utvärdering av eutrofieringstillstånd. Inom ABNORMAL har frågorna vidare fokuserats på användningen av ekologiska modeller för att utvärdera eutrofieringstillståndet in framtida klimat. Viktigaste rönet från studien är det föreslagna sättet att sammanföra observationer med resultat från en ensemble av ekologiska modeller för att utvärdera eutrofieringstillståndet i dagens klimat under fem olika år (2001-2005). Tröskelvärden och metoder från Oslo and Paris Commissionen (OSPAR) och Helsinki Commission (HELCOM) används och möjliga förbättringar av metoder diskuteras kort. Bedömningen av eutrofieringstillståndet visar att Kattegatt, de danska sunden, Finska viken, Gotlandsbassängen, samt största delarna av Arkonabassängen, Bornholmsbassängen och Egentliga Östersjön kan klassificeras som problemområden. Huvuddelen av Nordsjön och Skagerrak är icke-problem områden medan huvuddelarna av Bottenhavet, Bottenviken, Riga Bukten och hela sydöstra kontinentalkusten av Nordsjön kan klassificeras som potentiella problemområden.

  • 370.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Hansen, J.L.S:
    Department of Bioscience, Aarhus University, Denmark.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Molchanov, M.S.
    St. Petersburg Branch, P.P. Shirshov Institute of Oceanology, Russia.
    Ryabchenko, V.A.
    St. Petersburg Branch, P.P. Shirshov Institute of Oceanology, Russia.
    Skogen, Morten
    Institute of Marine Research, Norway.
    Eutrophication Status Report of the North Sea, Skagerrak, Kattegat and the Baltic Sea: A model study. Present and future climate2013Rapport (Annet vitenskapelig)
    Abstract [en]

    An ensemble of models has been used to assess eutrophication in the North Sea and Baltic Sea in the present and the future climate, using a method suggested in Almroth and Skogen (2010). In the control run, the assessment of eutrophication status according to the integration of the categorized assessment parameters indicates that the Kattegat, the Danish Straits, the Gulf of Finland, the Gotland Basin as well as main parts of the Arkona Basin, the Bornholm Basin, and the Baltic proper may be classified as problem areas. The main part of the North Sea and also the Skagerrak are non-problem areas while the main parts of the Gulf of Bothnia, Gulf of Riga and the entire southeastern continental coast of the North Sea may be classified as potential problem areas (Fig. 16).The temperature increase by itself will worsen the oxygen condition throughout the area and on top of this; elevated nutrient levels in the whole Baltic will amplify this effect due to elevated primary production. Therefore declining oxygen condition and increasing phytoplankton biomasses will be the main problem causing the areas to be classified as problem areas. In the Western Gotland Basin low oxygen seems to be the sole reason for this classification. In the North Sea, the classification as potential problem areas are due to high nitrate and N:P ratio. In the future climate scenarios most of the previous potential problem areas in the Baltic Sea have become problem areas, except for the Bothnian Bay where the situation remain fairly unchanged. Also in the North Sea there seems to be no obvious changes in the projected future climate. Comparing the ECHAM5 driven changes to simulations using the HadCM3 forcing show that; all changes except the surface layer winterDIN in the future climate have the same sign and that; the overall eutrophication status assessment is robust and insensitive to the choice of future scenario.

  • 371.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Lindqvist, Stina
    Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Edman, Moa
    SMHI, Forskningsavdelningen, Oceanografi.
    Wåhlstrom, Irene
    SMHI, Forskningsavdelningen, Oceanografi.
    Bartoli, Marco
    Klaipeda University, Lithuania.
    Burska, Dorota
    Institute of Oceanography, University of Gdansk, Poland.
    Carstensen, Jacob
    Aarhus University, Denmark.
    Hellemann, Dana
    Department of Environmental Sciences, University of Helsinki, Helsinki, Finland.
    Hietanen, Susanna
    Department of Environmental Sciences, University of Helsinki, Helsinki, Finland.
    Hulth, Stefan
    Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
    Janas, Urszula
    Institute of Oceanography, University of Gdansk, Poland.
    Kendzierska, Halina
    Institute of Oceanography, University of Gdansk, Poland.
    Pryputniewicz-Flis, Dorota
    Institute of Oceanography, University of Gdansk, Poland.
    Voss, Maren
    Leibniz Institute for Baltic Sea Research Warnemünde, Germany.
    Zilius, Mindaugas
    Klaipeda University, Lithuania.
    Linking process rates with modellingdata and ecosystem characteristics2017Rapport (Fagfellevurdert)
    Abstract [en]

    This report is related to the BONUS project “Nutrient Cocktails in COAstal zones of the Baltic Sea” alias COCOA. The aim of BONUS COCOA is to investigate physical, biogeochemical and biological processes in a combined and coordinated fashion to improve the understanding of the interaction of these processes on the removal of nutrients along the land-sea interface. The report is especially related to BONUS COCOA WP 6 in which the main objective is extrapolation of results from the BONUS COCOA learning sites to coastal sites around the Baltic Sea in general. Specific objectives of this deliverable (D6.4) were to connect observed process rates with modelling data and ecosystem characteristics.

    In the report we made statistical analyses of observations from BONUS COCOA study sites together with results from the Swedish Coastal zone Model (SCM). Eight structural variables (water depth, temperature, salinity, bottom water concentrations of oxygen, ammonium, nitrate and phosphate, as well as nitrogen content in sediment) were found common to both the experimentally determined and the model data sets. The observed process rate evaluated in this report was denitrification. In addition regressions were tested between observed denitrification rates and several structural variables (latitude, longitude, depth, light, temperature, salinity, grain class, porosity, loss of ignition, sediment organic carbon, total nitrogen content in the sediment,  sediment carbon/nitrogen-ratio, sediment chlorphyll-a as well as bottom water concentrations of oxygen, ammonium, nitrate, and dissolved inorganic  phosphorus and silicate) for pooled data from all learning sites.

    The statistical results showed that experimentally determined multivariate data set from the shallow, illuminated stations was mainly found to be similar to the multivariate data set produced by the SCM model. Generally, no strong correlations of simple relations between observed denitrification and available structural variables were found for data collected from all the learning sites. We found some non-significant correlation between denitrification rates and bottom water dissolved inorganic phosphorous and dissolved silica but the reason behind the correlations is not clear.

    We also developed and evaluated a theory to relate process rates to monitoring data and nutrient retention. The theoretical analysis included nutrient retention due to denitrification as well as burial of phosphorus and nitrogen. The theory of nutrient retention showed good correlations with model results. It was found that area-specific nitrogen and phosphorus retention capacity in a sub-basin depend much on mean water depth, water residence time, basin area and the mean nutrient concentrations in the active sediment layer and in the water column.

  • 372.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Martensson, S.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Modeling the impact of reduced sea ice cover in future climate on the Baltic Sea biogeochemistry2013Inngår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 40, nr 1, s. 149-154Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In a warming future climate, the sea ice cover is expected to decrease, with very likely large consequences for the marine ecosystem. We investigated the impact of future sea ice retreat on the Baltic Sea biogeochemistry at the end of the century, using an ensemble of regionalized global climate simulations. We found that the spring bloom will start by up to one month earlier and winds and wave-induced resuspension will increase, causing an increased transport of nutrients from the productive coastal zone into the deeper areas. The internal nutrient fluxes do not necessarily increase because they also depend on oxygen and temperature conditions of the bottom water. Winter mixing increases in areas having reduced ice cover and in areas having reduced stratification due to increased freshwater supply. The reduced sea ice cover therefore partly counteracts eutrophication because increased vertical mixing improves oxygen conditions in lower layers. Citation: Eilola, K., S. Martensson, and H. E. M. Meier (2013), Modeling the impact of reduced sea ice cover in future climate on the Baltic Sea biogeochemistry, Geophys. Res. Lett., 40, 149-154, doi:10.1029/2012GL054375.

  • 373.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    Höglund, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    Transports and budgets of oxygen and phosphorus in the Baltic sea2008Rapport (Annet vitenskapelig)
    Abstract [en]

    In this report we present budgets of oxygen and phosphorus for the deeper layers of the Baltic proper. The budgets give calculations of sedimentation, erosion and horizontal and vertical transports based on model simulations. The fluxes of oxygen and phosphorus as well as trends in contents have been computed.

  • 374.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Meier, Markus
    SMHI, Forskningsavdelningen, Oceanografi.
    Almroth-Rosell, Elin
    SMHI, Forskningsavdelningen, Oceanografi.
    On the dynamics of oxygen, phosphorus and cyanobacteria in the Baltic Sea; A model study2009Inngår i: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 75, nr 1-2, s. 163-184Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Oxygen and phosphorus dynamics and cyanobacterial blooms in the Baltic Sea are discussed using results from the Swedish Coastal and Ocean Biogeochemical model (SCOBI) coupled to the Rossby Centre Ocean model (RCO). The high-resolution circulation model is used to simulate the time period from 1902 to 1998 using reconstructed physical forcing and climatological nutrient loads of the late 20th century. The analysis of the results covers the last 30 years of the simulation period. The results emphasize the importance of internal phosphorus and oxygen dynamics, the variability of physical conditions and the natural long-term variability of phosphorus supplies from land on the phosphorus content in the Baltic Sea. These mechanisms play an important role on the variability of available surface layer phosphorus in late winter in the Baltic Sea. The content of cyanobacteria increases with the availability of phosphorus in the surface layers of the Baltic proper and the probability for large cyanobacteria blooms in the model is rapidly increased at higher concentrations of excess dissolved inorganic phosphorus in late winter. The natural increase of phosphorus supplies from land due to increased river runoff since the early 1970s may to a large degree explain the increased phosphorus content in the Baltic proper. Another significant fraction of the increase is explained by the release of phosphorus from increased anoxic areas during the period. These results refer to the long-term variability of the phosphorus cycle. In accordance to earlier publications is the short-term (i.e. interannual) variability of the phosphorus content in the Baltic proper mainly explained by oxygen dependent sediment fluxes. (c) 2008 Elsevier B.V. All rights reserved.

  • 375.
    Eilola, Kari
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Sahlberg, Jörgen
    SMHI, Affärsverksamhet.
    Model assessment of the predicted environmental consequences for OSPAR problem areas following nutrient reductions2009Rapport (Annet vitenskapelig)
    Abstract [en]

    The Swedish Coastal and Ocean Biogeochemical model (SCOBI) is used for the assessment of eutrophication status in the Skagerrak and the Kattegat, and of the following long-term effects on the ecosystem for the 50% nutrient reduction target (PARCOM Recommendation 88/2). Model validation and the final reporting of the results in accordance with the OSPAR comprehensive procedure are presented.The model is validated by a comparison of a long time series (1985-2002) of the model results to data from a number of stations representing different parts of the model domain. A quantitative examination of the model performance is done by a comparison between the seasonal and annual averages of the model results and in-situ data. The model response to nutrient reductions shows that reducing nutrient inputs from land have the largest effects on the nitrate concentrations in the Kattegat and along the Swedish coast in the Skagerrak. The effects on phosphate concentrations are relatively small. The largest effect obtained from a 50% reduction of anthropogenic nitrogen and phosphorus from the runoff in one country alone is obtained for Sweden. This model experiment reduces the nitrate and chlorophyll concentrations in the Swedish coastal waters by 5%-10% and 3%-6%, respectively. The annual net production is reduced by 2%-4% and changes in sedimentation are less than 1%. The largest reduction is found in the Kattegat.The combined effect from a 50% reduction of anthropogenic nutrient supplies from land and an anticipated realistic reduction of nutrient concentrations in the Baltic Sea and the North Sea reduces the nitrate and phosphate concentrations in the Kattegat and the Swedish parts of the Skagerrak coastal area by 20%-30%. The average chlorophyll concentrations are reduced by 8%-11%. The annual net production and the sedimentation are reduced by 12%-20% and 5%-12%, respectively.

  • 376. Eisner, S.
    et al.
    Floerke, M.
    Chamorro, A.
    Daggupati, P.
    Donnelly, Chantal
    SMHI, Forskningsavdelningen, Hydrologi.
    Huang, J.
    Hundecha, Yeshewatesfa
    SMHI, Forskningsavdelningen, Hydrologi.
    Koch, H.
    Kalugin, A.
    Krylenko, I.
    Mishra, V.
    Piniewski, M.
    Samaniego, L.
    Seidou, O.
    Wallner, M.
    Krysanova, V.
    An ensemble analysis of climate change impacts on streamflow seasonality across 11 large river basins2017Inngår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 141, nr 3, s. 401-417Artikkel i tidsskrift (Fagfellevurdert)
  • 377. Eissler, Y
    et al.
    Sahlsten, Elisabeth
    SMHI, Forskningsavdelningen, Oceanografi.
    Quinones, R A
    Effects of virus infection on respiration rates of marine phytoplankton and microplankton communities2003Inngår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 262, s. 71-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The possible influence of viral infection on respiration rates in marine microbial pelagic communities was assessed by means of 3 experiments on respiration rate with viral concentrate addition on single-species cultures of Mantoniella sp. and Micromonas pusilla and another 3 on natural microplankton communities (organisms < 200 mum) from the Kattegat Sea ((A) over circle stol) and the Baltic Sea. Coastal surface seawater samples were taken during cruises of the RVs 'Ancylus' and 'Argos' during winter and spring 2000. Approximately 50 to 70 l of seawater were concentrated by ultrafiltration. The experiments were started by adding a viral particle concentrate to a container with algae or a natural microplankton community; a control container was kept free of the viral concentrate addition. Oxygen concentration determinations were carried out on each treatment and control to measure respiration rates throughout the incubation period. The in vivo chlorophyll a fluorescence was also monitored as an indication of algal infection. The rates of respiration indicated that the addition of the viral particle concentrate affected the respective metabolisms of the Mantoniella sp. and Micromonas pusilla cultures as well as natural microplankton communities. Viral infection decreased the Mantoniella sp. respiration rate (by 96%) and increased the Micromonas pusilla respiration rate (by 235%). Hence, if our results can be extrapolated to nature, then, at least in a bloom situation, the fate of primary production and carbon fluxes could be strongly modulated by viral infection. The addition of a viral particle concentrate to the microplankton community generated complex responses in terms of respiration rates, which increased (by 84%) or remained similar to the controls. Our results suggest that viral infection of microplanktonic organisms could be one of the factors significantly modifying pelagic carbon fluxes.

  • 378.
    Eklund, Anna
    et al.
    SMHI, Samhälle och säkerhet.
    Axén Mårtensson, Jenny
    SMHI, Samhälle och säkerhet.
    Bergström, Sten
    SMHI, Forskningsavdelningen, Hydrologi.
    Björck, Emil
    SMHI, Affärsverksamhet.
    Dahné, Joel
    SMHI, Affärsverksamhet.
    Lindström, Lena
    SMHI, Samhälle och säkerhet.
    Olsson, Jonas
    SMHI, Forskningsavdelningen, Hydrologi.
    Simonsson, Lennart
    SMHI, Forskningsavdelningen, Hydrologi.
    Sjökvist, Elin
    SMHI, Affärsverksamhet.
    Sveriges framtida klimat: Underlag till Dricksvattenutredningen2015Rapport (Annet vitenskapelig)
    Abstract [sv]

    Det senaste resultatet från klimatforskningen har använts för att producera detaljerade analyser av Sveriges framtida klimat. Resultaten bygger på de klimatscenarier som använts av FN:s klimatpanel i dess femte utvärdering (AR5). I denna analys har två scenarier använts; RCP4.5 som innebär stora framtida utsläppsbegränsningar och RCP8.5 som innebär höga utsläpp av växthusgaser i framtiden. Beräkningar av framtidens klimat och vattentillgång bygger på nytt underlag och delvis nya förutsättningar jämfört med tidigare analyser som presenterats av SMHI. De stora dragen i den beräknade förändringen av nederbörd, temperatur, vattentillgång och flöden kvarstår från tidigare utredningar. Användningen av RCP8.5-scenariet, med sin höga framtida koncentration av växthusgaser, förstärker effekterna jämfört med tidigare publicerade analyser. Eftersom resultaten från FN:s klimatpanel (AR5) presenterades så sent som 2013 så har underlaget framtaget av SMHI präglats av ett intensivt utvecklingsarbete. Resultaten har krävt användande av ny metodik och resultaten kommer även fortsättningsvis att utvärderas av SMHI. Analysen har gjorts för ett antal parametrar som är relevanta för dricksvattenförsörjningen. I tabellen nedan visas en översiktlig sammanfattning av resultaten. Parameter Förändring Lufttemperatur Ökning i hela landet, främst i norra Sverige, främst vintertid. Medelnederbörd Ökning i hela landet, främst i Norrlands inland, främst vinter och vår. Kraftig korttidsnederbörd Ökning i hela landet, främst för de korta varaktigheterna. Vattentillgång Ökning av årsmedel i hela landet förutom östra Götaland. Ökningen är störst på vintern. Minskning på sommaren, främst i östra Götaland. 100-årsflöde och 200-årsflöde Ökning i stora delar av landet. Minskning i Norrlands inland och norra kustland samt nordvästra Svealand Lågflöden Mer vanligt i Götaland och Svealand, främst östra Götaland Havsnivåer Stigande havsnivå, nettoökningen störst i södra Sverige Temperatur Klimatberäkningarna visar på en ökning av årsmedeltemperaturen under innevarande sekel, men med stor spridning av resultaten. Störst beräknas ökningen bli i norr, vilket överensstämmer med tidigare resultat från såväl SMHI som IPCC. Skillnaderna mellan de två utsläppsscenarierna är små för perioden 2021-2050 men ökar mot slutet av århundradet. Scenario RCP4.5 innebär i medeltal en ökning på ca 3 grader till 2100 jämfört med perioden 1961-1990. För RCP8.5 är ökningen större, i medeltal ca 6 grader till 2100. Nederbörd Medelnederbörden beräknas öka i hela landet i framtiden. Störst väntas ökningen bli i Norrlands inland. Skillnaden mellan de två utsläppsscenarierna är små för perioden 2021-2050 men ökar mot slutet av århundradet. En ökning väntas under alla årstider, men främst för vintern och våren. Den extrema korttidsnederbörden beräknas bli mer intensiv i ett framtida klimat. Detta gäller främst skyfall med kort varaktighet. Vattentillgång och flöden I framtiden väntas sett över hela året en ökning av vattentillgången i stora delar av landet, främst i norra Sverige och längs Västkusten. I sydöstra Sverige väntas istället en minskning vilket beror på ökad avdunstning. I större delen av landet väntas vårfloden bli lägre och vinterflödena väntas istället öka. Ändringen i vattentillgång skiljer sig åt mellan olika årstider. Sommartid väntas en minskad vattentillgång i större delen av landet, med den största minskningen i östra Götaland. De extrema flödena väntas i framtiden inträffa mer sällan i Norrlands inland och norra kustland samt nordvästra Svealand. I övriga delar av landet väntas de extrema flödena bli vanligare. De nya beräkningarna visar att en större andel av Sveriges yta kan komma att utsättas för förstärkta extremflöden jämfört med tidigare beräkningar. I framtiden väntas antalet dagar med låga flöden bli fler i Götaland och stora delar av Svealand. Den största förändringen beräknas ske i östra Götaland. Detta är en följd av att avdunstningen ökar till följd av ökad temperatur. Havsnivå Den globala havsnivån väntas stiga i framtiden. En beräknad övre gräns för ökningen är ungefär 1 m till år 2100 enligt IPCC:s senaste utvärdering. Landhöjningen motverkar havsnivåhöjningen, speciellt i norra Sverige.

  • 379.
    Eliasson, Salomon
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Karlsson, Karl-Göran
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    van Meijgaard, Erik
    Meirink, Jan Fokke
    Stengel, Martin
    Willén, Ulrika
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    The Cloud_cci simulator v1.0 for the Cloud_cci climate data record and its application to a global and a regional climate model2019Inngår i: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 12, nr 2, s. 829-847Artikkel i tidsskrift (Fagfellevurdert)
  • 380.
    Eliasson, Salomon
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Tetzlaff, Anke
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Karlsson, Karl-Göran
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Prototyping an improved PPS cloud detection for the Arctic polar night2007Rapport (Annet vitenskapelig)
    Abstract [sv]

    under noll grader och snö och regn är vanligt förekommande, vilket bl.a. skapar hala vägar och behov av

  • 381. Emberson, L. D.
    et al.
    Bueker, P.
    Ashmore, M. R.
    Mills, G.
    Jackson, L. S.
    Agrawal, M.
    Atikuzzaman, M. D.
    Cinderby, S.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Jamir, C.
    Kobayashi, K.
    Oanh, N. T. K.
    Quadir, Q. F.
    Wahid, A.
    A comparison of North American and Asian exposure-response data for ozone effects on crop yields2009Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 43, nr 12, s. 1945-1953Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Modelling-based studies to assess the extent and magnitude of ozone (O-3) risk to agriculture in Asia suggest that yield losses of 5-20% for important crops may be common in areas experiencing elevated O-3 concentrations. These assessments have relied on European and North American dose-response relationships and hence assumed an equivalent Asian crop response to O-3 for local cultivars, pollutant conditions and climate. To test this assumption we collated comparable dose-response data derived from fumigation, filtration and EDU experiments conducted in Asia on wheat. rice and leguminous crop species. These data are pooled and compared with equivalent North American dose-response relationships. The Asian data show that at ambient O-3 concentrations found at the study sites (which vary between similar to 35-75 ppb 4-8 h growing season mean), yield losses for wheat, rice and legumes range between 5-48, 3-47 and 10-65%, respectively. The results indicate that Asian grown wheat and rice cultivars are more sensitive to O-3 than the North American dose-response relationships would suggest. For legumes the scatter in the data makes it difficult to reach any equivalent conclusion in relative sensitivities. As such, existing modelling-based risk assessments may have substantially underestimated the scale of the problem in Asia through use of North American derived dose-response relationships. (c) 2009 Elsevier Ltd. All rights reserved.

  • 382. Emerton, Rebecca E.
    et al.
    Stephens, Elisabeth M.
    Pappenberger, Florian
    Pagano, Thomas C.
    Weerts, Albrecht H.
    Wood, Andy W.
    Salamon, Peter
    Brown, James D.
    Hjerdt, Niclas
    SMHI, Samhälle och säkerhet.
    Donnelly, Chantal
    SMHI, Forskningsavdelningen, Hydrologi.
    Baugh, Calum A.
    Cloke, Hannah L.
    Continental and global scale flood forecasting systems2016Inngår i: WILEY INTERDISCIPLINARY REVIEWS-WATER, Vol. 3, nr 3, s. 391-418Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Floods are the most frequent of natural disasters, affecting millions of people across the globe every year. The anticipation and forecasting of floods at the global scale is crucial to preparing for severe events and providing early awareness where local flood models and warning services may not exist. As numerical weather prediction models continue to improve, operational centers are increasingly using their meteorological output to drive hydrological models, creating hydrometeorological systems capable of forecasting river flow and flood events at much longer lead times than has previously been possible. Furthermore, developments in, for example, modelling capabilities, data, and resources in recent years have made it possible to produce global scale flood forecasting systems. In this paper, the current state of operational large-scale flood forecasting is discussed, including probabilistic forecasting of floods using ensemble prediction systems. Six state-of-the-art operational large-scale flood forecasting systems are reviewed, describing similarities and differences in their approaches to forecasting floods at the global and continental scale. Operational systems currently have the capability to produce coarse-scale discharge forecasts in the medium-range and disseminate forecasts and, in some cases, early warning products in real time across the globe, in support of national forecasting capabilities. With improvements in seasonal weather forecasting, future advances may include more seamless hydrological forecasting at the global scale alongside a move towards multi-model forecasts and grand ensemble techniques, responding to the requirement of developing multi-hazard early warning systems for disaster risk reduction. (C) 2016 The Authors. WIREs Water published by Wiley Periodicals, Inc.

  • 383. Emmons, L. K.
    et al.
    Arnold, S. R.
    Monks, S. A.
    Huijnen, V.
    Tilmes, S.
    Law, K. S.
    Thomas, J. L.
    Raut, J. -C
    Bouarar, I.
    Turquety, S.
    Long, Y.
    Duncan, B.
    Steenrod, S.
    Strode, S.
    Flemming, J.
    Mao, J.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Thompson, A. M.
    Tarasick, D.
    Apel, E. C.
    Blake, D. R.
    Cohen, R. C.
    Dibb, J.
    Diskin, G. S.
    Fried, A.
    Hall, S. R.
    Huey, L. G.
    Weinheimer, A. J.
    Wisthaler, A.
    Mikoviny, T.
    Nowak, J.
    Peischl, J.
    Roberts, J. M.
    Ryerson, T.
    Warneke, C.
    Helmig, D.
    The POLARCAT Model Intercomparison Project (POLMIP): overview and evaluation with observations2015Inngår i: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 15, nr 12, s. 6721-6744Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A model intercomparison activity was inspired by the large suite of observations of atmospheric composition made during the International Polar Year (2008) in the Arctic. Nine global and two regional chemical transport models participated in this intercomparison and performed simulations for 2008 using a common emissions inventory to assess the differences in model chemistry and transport schemes. This paper summarizes the models and compares their simulations of ozone and its precursors and presents an evaluation of the simulations using a variety of surface, balloon, aircraft and satellite observations. Each type of measurement has some limitations in spatial or temporal coverage or in composition, but together they assist in quantifying the limitations of the models in the Arctic and surrounding regions. Despite using the same emissions, large differences are seen among the models. The cloud fields and photolysis rates are shown to vary greatly among the models, indicating one source of the differences in the simulated chemical species. The largest differences among models, and between models and observations, are in NOy partitioning (PAN vs. HNO3) and in oxygenated volatile organic compounds (VOCs) such as acetaldehyde and acetone. Comparisons to surface site measurements of ethane and propane indicate that the emissions of these species are significantly underestimated. Satellite observations of NO2 from the OMI (Ozone Monitoring Instrument) have been used to evaluate the models over source regions, indicating anthropogenic emissions are underestimated in East Asia, but fire emissions are generally overestimated. The emission factors for wildfires in Canada are evaluated using the correlations of VOCs to CO in the model output in comparison to enhancement factors derived from aircraft observations, showing reasonable agreement for methanol and acetaldehyde but underestimate ethanol, propane and acetone, while overestimating ethane emission factors.

  • 384. Endris, Hussen Seid
    et al.
    Lennard, Christopher
    Hewitson, Bruce
    Dosio, Alessandro
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Artan, Guleid A.
    Future changes in rainfall associated with ENSO, IOD and changes in the mean state over Eastern Africa2019Inngår i: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 52, nr 3-4, s. 2029-2053Artikkel i tidsskrift (Fagfellevurdert)
  • 385. Endris, Hussen Seid
    et al.
    Lennard, Christopher
    Hewitson, Bruce
    Dosio, Alessandro
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Panitz, Hans-Juergen
    Teleconnection responses in multi-GCM driven CORDEX RCMs over Eastern Africa2016Inngår i: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 46, nr 9-10, s. 2821-2846Artikkel i tidsskrift (Fagfellevurdert)
  • 386. Endris, Hussen Seid
    et al.
    Omondi, Philip
    Jain, Suman
    Lennard, Christopher
    Hewitson, Bruce
    Chang'a, Ladislaus
    Awange, J. L.
    Dosio, Alessandro
    Ketiem, Patrick
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Panitz, Hans-Juergen
    Buechner, Matthias
    Stordal, Frode
    Tazalika, Lukiya
    Assessment of the Performance of CORDEX Regional Climate Models in Simulating East African Rainfall2013Inngår i: Journal of Climate, ISSN 0894-8755, E-ISSN 1520-0442, Vol. 26, nr 21, s. 8453-8475Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This study evaluates the ability of 10 regional climate models (RCMs) from the Coordinated Regional Climate Downscaling Experiment (CORDEX) in simulating the characteristics of rainfall patterns over eastern Africa. The seasonal climatology, annual rainfall cycles, and interannual variability of RCM output have been assessed over three homogeneous subregions against a number of observational datasets. The ability of the RCMs in simulating large-scale global climate forcing signals is further assessed by compositing the El Nino-Southern Oscillation (ENSO) and Indian Ocean dipole (IOD) events. It is found that most RCMs reasonably simulate the main features of the rainfall climatology over the three subregions and also reproduce the majority of the documented regional responses to ENSO and IOD forcings. At the same time the analysis shows significant biases in individual models depending on subregion and season; however, the ensemble mean has better agreement with observation than individual models. In general, the analysis herein demonstrates that the multimodel ensemble mean simulates eastern Africa rainfall adequately and can therefore be used for the assessment of future climate projections for the region.

  • 387. Eneroth, K
    et al.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Holmen, K
    A trajectory climatology for Svalbard; investigating how atmospheric flow patterns influence observed tracer concentrations2003Inngår i: Physics and Chemistry of the Earth, ISSN 1474-7065, E-ISSN 1873-5193, Vol. 28, nr 28-32, s. 1191-1203Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A 10-year climatology of long-range atmospheric transport to Ny-(A) over circle lesund, Svalbard (78.9degreesN, 11.9degreesE) is developed using three-dimensional 5-day back-trajectories. We calculate trajectories arriving twice daily at 950, 850 and 750 hPa during 1992-2001, using European Centre for Medium-Range Weather Forecasts (ECMWF) analyzed wind, fields. Cluster analysis is used to classify the trajectories into distinct transport patterns. The clustering procedure is performed on the whole 10-year set of trajectories, to study both year-to-year and mouth-to-mouth variability in the synoptic-scale atmospheric circulation. We identify eight major transport patterns to Ny-(A) over circle lesund, which we find to be consistent with mean-pressure charts of the Arctic region. The distribution of trajectories between these flows is similar for all years during the 10-year period. However, there are seasonal differences in when different clusters are most prevalent. The calculated clusters provide an indication of source regions and transport pathways influencing Svalbard at different times of the year. Such information is valuable for interpreting measured time-series of trace gases and aerosols and could serve as guidance for formulating sampling strategies. We compare the trajectory clusters to CO2 measurements to study to what degree different atmospheric flow patterns influence the variability of the atmospheric CO2. Overall we see a linkage between CO2 concentration and the large-scale circulation. For instance, in connection with transport over Europe and Siberia during winter, high CO2 mixing ratios are observed, whereas trajectories originating from the Atlantic are associated with low CO2 concentrations. However, during some periods and for some individual trajectories we see no conclusive linkage between variability in atmospheric CO2 and transport. This can be due to a combination of the complex structure Of CO2 sources and sinks and its relatively long atmospheric turn-over time. CO2 and Rn-222 mixing ratios are calculated using the three-dimensional transport model MATCH to further illustrate these characteristics of CO2. (C) 2003 Elsevier Ltd. All rights reserved.

  • 388.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Assessing ground-level ozone (O3) impacts to crops in parts of Asia and southern Africa: The Regional Air Pollution in Developping Countries (RAPIDC) Crops Project.2010Inngår i: Air Pollution Health and Environmental Impacts, CRC Press , 2010, s. 421-446Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 389.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Modelling of near-surface ozone over South Asia2008Inngår i: Journal of Atmospheric Chemistry, ISSN 0167-7764, E-ISSN 1573-0662, Vol. 59, nr 1, s. 61-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hourly, three-dimensional, fields of tropospheric ozone have been produced for 12 consecutive months on a domain covering South Asia, using the regional Eulerian off-line chemistry transport model MATCH. The results were compared with background observations to investigate diurnal and seasonal variations of near-surface ozone in the region. MATCH reproduced the seasonality of near-surface ozone at most locations in the area. However, the current, and previous, studies indicate that the model consequently overestimate night-time concentrations, while it occasionally underestimates the day-time, near-surface, ozone concentrations. The lowest monthly-mean concentrations of near-surface ozone are typically experienced in June-September, coincident with the rainy season in most areas. The seasonality is not identical across the domain; some locations have a completely different trend. Large areas in Northern India and Nepal show a secondary minimum during the cold winter season (December-January). High concentrations of near-surface ozone are found over the oceans, close to the Indian subcontinent, due to the less efficient dry deposition to water surfaces; over parts of Tibet due to influence of free tropospheric air and little deposition to snow covered surfaces; and along the Gangetic valley due to the large emissions of precursors in this region. Monthly-mean ozone concentrations in the densely populated northern India range from 30-45 ppb(v). The model results were also used to produce maps of AOT40. The results point towards similar levels of AOT40 in India as in Europe: large areas of India show 3-month AOT40 values above 3 ppm(v) hours.

  • 390.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sulphur simulations for East Asia using the MATCH model with meteorological data from ECMWF2000Rapport (Annet vitenskapelig)
  • 391.
    Engardt, Magnuz
    SMHI, Forskningsavdelningen, Luftmiljö.
    Sulphur simulations for East Asia using the match model with meteorological data from ECMWF2001Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 130, nr 1-4, s. 289-294Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sulphur transport and conversion calculations have been conducted over an East Asian domain as part of a model intercomparison exercise. We hereby describe the MATCH model, used in the study, and discuss the results achieved with different model configurations. We find that is often more critical to choose a representative gridbox value than selecting a specific parameter value from the suite available. The modelled, near-surface, atmospheric concentration of total-sulphur (SO2+sulphate) in eastern China is typically 5-10 mug S m(-3), with large areas exceeding 20 mug S m(3). In southern Japan the values range from 2-5 mug S m(-3). Atmospheric SO2 dominates over sulphate near the emission regions while sulphate concentrations are higher over e.g. the western Pacific. The sulphur deposition exceeds several g sulphur m(-2) year m(-1) in large areas of China. Southern Japan receives 0.5-1 S m(-2) year(-1).

  • 392.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Alpfjord, Helene
    SMHI, Affärsverksamhet.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    PODY-beräkningar med MATCH Sverigesystemet2016Rapport (Annet vitenskapelig)
    Abstract [sv]

    Vi har utvecklat ett programpaket som möjliggör PODY beräkningar i MATCH Sverigesystemet. Rapporten ger en kortfattad introduktion till PODY och går igenom implementeringen i MATCH-systemet.

    Resultat för receptorerna generic crops (POD3gen-CR) och generic deciduous trees (POD1gen-DT) presenteras för åren 2013-2015 och jämförs med motsvarande data från EMEP-modellen. POD3gen-CR uppvisar stor år-till-år variation och MATCH-resultaten är tydligt högre än motsvarande uppskattningar av EMEP-modellen. POD1gen-DT varierar mindre från år till år och resultaten från MATCH och EMEP-modellen överensstämmer bättre.

    PODY presenteras tillsammans med övriga ozonmått på SMHI:s miljöövervakningssida (www.smhi.se/klimatdata/miljo/atmosfarskemi) med start från miljöövervakningsåret 2013.

  • 393.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Modellering av marknära ozon: Regionala och högupplösta tillämpningar av MATCH2011Rapport (Annet vitenskapelig)
    Abstract [sv]

    Höga halter av marknära ozon uppträder i Sverige framförallt under våren och sommaren i de sydvästra delarna av landet. SMHI:s regionala spridningsmodell, MATCH, klarar Luftdirektivets krav påmodellkvalitet för ozon i svensk bakgrundsluft. Detta gäller både för en Europaskalig tillämpning med 44×44 km2 stora gridrutor samt en högupplöst tillämpning med 5×5 km2 stora gridrutor. En högupplöst modell ger marginell förbättring av de statistiska måtten som beskriver modellens förmåga att beräkna marknära ozon. Lokalt bidrag till överskridanden (i förorter) är troligen inte ett problem i Sverige. Även om MATCH-modellen klarar Luftdirektivets krav på modellkvalitet klarar den inte alltid av att beskriva episoderna med de allra högsta halterna. Detta är en allvarlig brist i modellsystemet. Bättre information om utsläpp av ozongenererande ämnen, i framför allt östra Europa, och förbättringar av modellens beskrivning av vertikal omblandning och deposition kan förmodligen förbättra möjligheterna att fånga de högsta ozonhalterna. 2-dimensionell variationell analys kan vara ett verktyg att få en geografiskt täckande uppskattning på marknära ozon över Sverige, speciellt på måtten AOT40 och överskridandedagar. Modellresultat, i form av MATCH-fält och 2-dimensionellt variationellt analyserade fält, kan användas som komplement till mätningar.

  • 394.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Bergström, Robert
    SMHI, Forskningsavdelningen, Luftmiljö.
    Andersson, Camilla
    SMHI, Forskningsavdelningen, Luftmiljö.
    Climate and Emission Changes Contributing to Changes in Near-surface Ozone in Europe over the Coming Decades: Results from Model Studies2009Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 38, nr 8, s. 452-458Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We used an off-line, regional, model of atmospheric transport and chemistry to investigate current and future levels of near-surface ozone and accumulated ozone exposure over a threshold of 40 ppb(v) (AOT40) in Europe. To describe the current situation and enable an evaluation of the model's performance we simulated a number of years around 2000. To assess changes in ozone concentrations due to possible emission changes in Europe, the model was run with the meteorology of the early 2000s and precursor emissions from a set of Clean Air for Europe (CAFE) emissions scenarios. By extrapolation of the observed increase in near-surface O(3) at coastal locations in northwest Europe we constructed model boundaries that were used to simulate the impact of increasing hemispheric background in 2020. To assess changes in ozone concentrations due to climate change, the model was run with recent (2000) emissions but using meteorology from a regional climate model simulating a control (1961-1990) and a future (2021-2050) climate. The results indicate that climate change will have a small impact on ozone concentrations and AOT40 in the Nordic countries. Changes in hemispheric background concentrations and changes in precursor emissions in Europe will have a larger effect on ozone in Northern Europe. The situation is quite different in southern Europe, where climate change is expected to result in a very large increase in near-surface ozone concentrations.

  • 395.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Foltescu, Valentin
    SMHI, Forskningsavdelningen, Luftmiljö.
    Luftföroreningar i Europa under framtida klimat2007Rapport (Annet vitenskapelig)
    Abstract [sv]

    Ozonmedelhalterna förväntas öka markant (1-2% per decennium, fram till 2050) i centrala och södra Europa, framförallt under sommaren. Maximumhalterna ökar mer än medelhalterna. Nordligaste Europa förväntas få minskande halter, speciellt under vår och höst. Östra Europa får minskande ozonhalter under vintern. I södra Skandinavien ser vi bara små förändringar i ozonhalterna under alla årstider. Halten av marknära sekundära inorganiska partiklar (SIA; Secondary Inorganic Aerosols) ökar kraftigt (3-5% per decennium, fram till 2050) i hela kontinentala Europa under alla årstider förutom vinter. Ökningen är störst runt Medelhavet på sommaren, och halterna är mer än 20% högre under 30-års perioden 2021-2050 jämfört med dagens nivåer. 2071-2100 beräknas partikelhalterna under sommaren vara minst 50% högre, jämfört med dagens situation, i stora områden av södra och centrala Europa. Södra Skandinavien torde få en måttlig ökning av SIA under framförallt under vår och sommar. Nordliga delar av modellområdet uppvisar minskande SIA halter under alla årstider. Våtdepositionen av svavel- och kväveföreningar minskar mycket kraftigt i södra och västra Europa under alla årstider, speciellt under den senare delen av simuleringsperioden (2021- 2050 till 2071-2100). Stora områden i och kring Medelhavet samt delar av Frankrike, Belgien och Nederländerna får endast 50%, eller mindre, av dagens deposition under perioden 2071- 2100. Norges kust förväntas få en ökad våtdeposition i framtida klimat, speciellt under våren och sommaren. Ökningen är större än 50% på flera platser, men det är trots allt en relativt liten yta som påverkas på detta sätt. Minskad (ökad) våtdeposition i modellområdet kompenseras i någon mån av ökad (minskad) torrdeposition. För de flesta områdena kommer dock ändringen i totaldeposition att följa mönstret i våtdepositionen. Resultaten tyder på att flera sekundära luftföroreningar blir mer långlivade. Halterna i atmosfären blir därmed högre, de kommer vidare att kunna spridas över större områden.

  • 396.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Holmen, K
    Model simulations of anthropogenic-CO2 transport to an Arctic monitoring station during winter1999Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 51, nr 2, s. 194-209Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We describe, and use, a limited area, 3-dimensional transport model. The model domain is located over the Arctic, but includes the majority of the anthropogenic CO2 emissions in western and eastern Europe, which together make up about 1/3 of the global CO2 emissions. The model is run for several winter periods, using anthropogenic CO2 emissions only, and the results are compared with independent CO2 measurements taken at a monitoring station on Spitsbergen in the high Arctic. We show that the initial concentrations and boundary values of the domain are not crucial for the results, and conclude that most of the measured variability above the winter baseline in CO2 at the Arctic monitoring station emanates from recent CO2 sources within the model domain. From the observed small spatial variability in the monthly mean atmospheric CO2 mixing ratio in the north Atlantic region, we assume that there is only little net exchange between the atmosphere and ocean during the studied periods. Based on the co-variation between CO2 and particulate mass,we hypothesise that most of the measured CO2 variability is due to anthropogenic fossil fuel emissions, although we can not rule out a biogenic CO2 component. Using the transport model, we compare different estimates of fossil-fuel consumption in the mid-latitudes. We find that the industrial centres and the surrounding gas-fields in the lower-Ob region (60 degrees-72 degrees N, 65 degrees-80 degrees E) occasionally have a much larger impact on the CO2 measurements at Spitsbergen than follows from a recent CO2 emission inventory. This implies that there may be an overlooked CO2 source in this region, possibly flaring of gas.

  • 397.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Langner, Joakim
    SMHI, Forskningsavdelningen, Luftmiljö.
    Simulations of future sulphur and nitrogen deposition over Europe using meteorological data from three regional climate projections2013Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 65, artikkel-id 20348Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We use a regional model of atmospheric chemistry and transport to investigate trends in sulphur and nitrogen deposition over Europe during the first half of the 21st century. To assess changes due to climate change, the model was operated with meteorology from a regional climate model simulating present and future climates. The sensitivity of the deposition calculations to uncertainties in the climate projections was explored by using output from three different climate models. Changes in anthropogenic air pollution emissions in Europe were extracted from the gridded RCP4.5 emission inventory. The modelling systems were evaluated by comparing average modelled precipitation, deposition and concentrations over a 20-year period with observations collected around the year 2000. We conclude that the deposition of sulphur and nitrogen containing species will mainly be governed by changes in European emissions of these species over the period 2000-2050. If future emissions follow the pathway of the RCP4.5 scenario, Europe can expect significantly lower deposition of sulphur and oxidised nitrogen in 2050 compared to 2000. For reduced nitrogen, large areas of western Europe will receive considerably more deposition in 2050 than in 2000, due to feedback of decreased sulphur concentrations on the atmospheric turnover time of reduced nitrogen. Domain averaged reductions of total deposition from 2000 to 2050 are 63, 41 and 0.9% for sulphur, oxidised-and reduced nitrogen, respectively. Climate change results in decreased wet deposition of sulphur and reduced nitrogen leading to increased atmospheric turnover time of these species. Climate and emission changes lead to decreased atmospheric turnover times of reduced nitrogen but increased atmospheric turnover times of sulphur and oxidised nitrogen. These relations are likely leading to altered source-receptor relations in the future.

  • 398.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Leong, C P
    Regional modelling of anthropogenic sulphur in Southeast Asia2001Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 35, nr 34, s. 5935-5947Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A co-operative research project between the Malaysian Meteorological Service (MMS) and the Swedish Meteorological and Hydrological Institute (SMHI) focussing on the usage of an atmospheric transport and chemistry model, has just been initiated. Here, we describe the main features of the dispersion model and discuss a first set of calculations in light of available measurements of sulphuric species in Southeast Asia. According to our results, anthropogenic sulphur concentrations and depositions are particularly high near the large cities of the region, around a metal smelter in the southern Philippines, and in a region extending from northern Vietnam into southeastern China. These areas coincide with the high-emissions regions of Southeast Asia and we tentatively conclude that regional transport of acidifying species is not as far-reaching as in the mid-latitudes. From our calculations, and from supporting measurements we conclude that most of rural Southeast Asia is not yet severely affected by anthropogenic sulphur, but given the rapid rate of economical development in this region the situation may deteriorate quickly. Areas that are particularly at risk include the large cities, northern Vietnam, most of central Thailand, most of peninsular Malaysia, eastern Sumatra and parts of Java, all of which receive total-sulphur depositions in excess of 0.5 g S m(-2) yr(-1). Our model simulates sulphate in precipitation in accordance with measurements, but it has a tendency to overestimate atmospheric SO2. It remains to be investigated whether this is a problem in the model formulation or a result of unrepresentative sampling. An immediate continuation of this study should be performed with higher spatial resolution than the currently used 100 x 100 km(2). Other imperfections in this model study, which should be addressed in future work, include parameterised vertical transport in deep convective clouds, the influence of natural emissions (primarily from volcanoes) on the concentration and deposition of sulphuric species, and the year-to-year variability of the driving meteorological conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.

  • 399.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Simpson, David
    Schwikowski, Margit
    Granat, Lennart
    Deposition of sulphur and nitrogen in Europe 1900-2050. Model calculations and comparison to historical observations2017Inngår i: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 69, artikkel-id 1328945Artikkel i tidsskrift (Fagfellevurdert)
  • 400.
    Engardt, Magnuz
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Siniarovina, U
    Khairul, N I
    Leong, C P
    Country to country transport of anthropogenic sulphur in Southeast Asia2005Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 39, nr 28, s. 5137-5148Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The MATCH model-driven by archived meteorological data from the ECMWF-has been used to study the long-range transport of pollutants in Southeast Asia during the year 2000. We have specifically investigated the atmospheric export and import of anthropogenic sulphur between nine countries in Southeast Asia as well as the import to these countries from the boundaries of our model domain, from southern China, and from international shipping in the surrounding waters. Compared to the conditions at the mid-latitudes (Europe, North America and East Asia), we find less long-range transport in this part of the world. In all countries in the region (except those with very small area, i.e. Singapore and Brunei), did the major part of the domestic emissions (60-70%) fall down on the emitting country itself. The fraction of the countries own emissions contributing to the total, annually accumulated, national deposition varied from 10% for Laos-which is a country with small emissions neighbouring large emitters-to 80-90% in countries not surrounded by significant emitters (i.e. Thailand, Indonesia, Singapore and Brunei). Sensitivity tests were performed to explore the uncertainties in the model simulations and to investigate to what extent the current results could be used for source-receptor relationships in the future, when the magnitude and location of the emissions may be different. We found that the general feature-with relatively little long-range transport of sulphur-will not be altered, while the absolute magnitude of the deposition in areas downwind of large emitters could change considerably if certain model parameters, or the emission patterns are changed. This is particularly true in light of the seasonal variation of the deposition pathways. The atmospheric import of anthropogenic sulphur from specific countries can vary by an order of magnitude between different months. Incidentally, a decrease in import from one country during a certain period is often compensated by a roughly equal increase of the import from another country during the same time. (c) 2005 Elsevier Ltd. All rights reserved.

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