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  • 1.
    Belusic, Danijel
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Berg, Peter
    SMHI, Forskningsavdelningen, Hydrologi.
    Bozhinova, Denica
    SMHI, Forskningsavdelningen, Hydrologi.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Doescher, Ralf
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Eronn, Anna
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Klehmet, Katharina
    SMHI, Forskningsavdelningen, Hydrologi.
    Martins, Helena
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nilsson, Carin
    Olsson, Jonas
    SMHI, Forskningsavdelningen, Hydrologi.
    Photiadou, Christiana
    SMHI, Forskningsavdelningen, Hydrologi.
    Segersson, David
    SMHI, Forskningsavdelningen, Luftmiljö.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Climate Extremes for Sweden2019Rapport (Övrigt vetenskapligt)
  • 2. Berlin, Mats
    et al.
    Persson, Torgny
    Jansson, Gunnar
    Haapanen, Matti
    Ruotsalainen, Seppo
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Gull, Bengt Andersson
    Scots pine transfer effect models for growth and survival in Sweden and Finland2016Ingår i: Silva Fennica, ISSN 0037-5330, E-ISSN 2242-4075, Vol. 50, nr 3, artikel-id 1562Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this study, we developed models of transfer effects for growth and survival of Scots pine (Pinus sylvestris L.) in Sweden and Finland using a general linear mixed-model approach. For model development, we used 378 provenance and progeny trials with a total of 276 unimproved genetic entries (provenances and stand seed check-lots) distributed over a wide variety of climatic conditions in both countries. In addition, we used 119 progeny trials with 3921 selected genetic entries (open-and control pollinated plus-tree families) for testing model performance. As explanatory variables, both climatic indices derived from high-resolution gridded climate datasets and geographical variables were used. For transfer, latitude (photoperiod) and, for describing the site, temperature sum were found to be main drivers for both survival and growth. In addition, interaction terms (between transfer in latitude and site altitude for survival, and transfer in latitude and temperature sum for growth) entail changed reaction patterns of the models depending on climatic conditions of the growing site. The new models behave in a way that corresponds well to previous studies and recommendations for both countries. The model performance was tested using selected plus-trees from open and control pollinated progeny tests. Results imply that the models are valid for both countries and perform well also for genetically improved material. These models are the first step in developing common deployment recommendations for genetically improved forest regeneration material in both Sweden and Finland.

  • 3. Bjorkman, Christer
    et al.
    Kindvall, Oskar
    Hoglund, Solveig
    Lilja, Anna
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Eklund, Karin
    High Temperature Triggers Latent Variation among Individuals: Oviposition Rate and Probability for Outbreaks2011Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, nr 1, artikel-id e16590Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: It is anticipated that extreme population events, such as extinctions and outbreaks, will become more frequent as a consequence of climate change. To evaluate the increased probability of such events, it is crucial to understand the mechanisms involved. Variation between individuals in their response to climatic factors is an important consideration, especially if microevolution is expected to change the composition of populations. Methodology/Principal Findings: Here we present data of a willow leaf beetle species, showing high variation among individuals in oviposition rate at a high temperature (20 degrees C). It is particularly noteworthy that not all individuals responded to changes in temperature; individuals laying few eggs at 20 degrees C continued to do so when transferred to 12 degrees C, whereas individuals that laid many eggs at 20 degrees C reduced their oviposition and laid the same number of eggs as the others when transferred to 12 degrees C. When transferred back to 20 degrees C most individuals reverted to their original oviposition rate. Thus, high variation among individuals was only observed at the higher temperature. Using a simple population model and based on regional climate change scenarios we show that the probability of outbreaks increases if there is a realistic increase in the number of warm summers. The probability of outbreaks also increased with increasing heritability of the ability to respond to increased temperature. Conclusions/Significance: If climate becomes warmer and there is latent variation among individuals in their temperature response, the probability for outbreaks may increase. However, the likelihood for microevolution to play a role may be low. This conclusion is based on the fact that it has been difficult to show that microevolution affect the probability for extinctions. Our results highlight the urge for cautiousness when predicting the future concerning probabilities for extreme population events.

  • 4.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Berlin, Mats
    Andersson Gull, Bengt
    Tailored climate indices for climate-proofing operational forestry applications in Sweden and Finland2017Ingår i: International Journal of Climatology, ISSN 0899-8418, E-ISSN 1097-0088, Vol. 37, nr 1, s. 123-142Artikel i tidskrift (Refereegranskat)
  • 5.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Christensen, Jens
    Déqué, Michel
    Giorgi, Filippo
    Jones, Colin
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jones, Richard
    Laprise, René
    Rummukainen, Markku
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    von Storch, Hans
    Synthesis of Workshop2005Ingår i: Extended abstracts of a WMO/WCRP-sponsored Regional-Scale Climate Modelling Workshop : high-resolution climate modelling : assessment, added value and applications, Lund, Sweden, 29 March-2 April 2004 / [ed] Bärring, Lars; René, Laprise, Department of Physical Geography & Ecosystem Analysis, Lund University, Sweden , 2005, s. 18-25Konferensbidrag (Övrigt vetenskapligt)
  • 6.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Fortuniak, Krzysztof
    Multi-indices analysis of southern Scandinavian storminess 1780-2005 and links to interdecadal variations in the NW Europe-North Sea region2009Ingår i: International Journal of Climatology, ISSN 0899-8418, E-ISSN 1097-0088, Vol. 29, nr 3, s. 373-384Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Extra-tropical cyclone frequency and intensity are Currently under intense scrutiny because of the destruction recent windstorms have brought to Europe, and because they are a major meridional heat transport mechanism that may respond to differential latitudinal warming trends. Several studies using reanalysis data covering the second half of the 20th century Suggest increasing storm intensity in the northeastern Atlantic and European sector. Fewer analyses cover a longer time period but show different trends or point towards the dominance of interdecadal variability instead of ally clear trends. Hence, it is relevant to analyse cyclone variability over as long a period as possible. In this Study, we analyse interdecadal variability in cyclone activity over northwestern Europe back to AD 1780 by combining information from eight storminess indices applied in all Eulerian framework. These indices, including four new approaches towards gauging cyclone activity, use the series of thrice-daily sea level pressure observations at Lund and Stockholm. We find pronounced interdecadal variability in cyclonic activity but no significant overall consistent long-term trend. The major interdecadal-scale variability common to all indices is in good agreement with geostrophic wind reconstructions for NE Atlantic and NW Europe, and with variations in the North Atlantic oscillation (NAO). Our results show that the reanalysis studies cover a time period chiefly coinciding with a marked, but not exceptional in our 225-year perspective, positive variation in the regional cyclone activity that has more recently reversed. Because of the interdecadal variations, a near-centennial time perspective is needed when analysing variations in extra-tropical cyclone activity and the associated weather conditions over northwestern Europe. Copyright (C) 2009 Royal Meteorological Society

  • 7.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Holt, Tom
    Linderson, Maj-Lena
    Radziejewski, Madej
    Moriondo, Marco
    Palutikof, Jean P.
    Defining dry/wet spells for point observations, observed area averages, and regional climate model gridboxes in Europe2006Ingår i: Climate Research (CR), ISSN 0936-577X, E-ISSN 1616-1572, Vol. 31, nr 1, s. 35-49Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new method for optimising threshold values of dry/wet spells is evaluated. A set of indices is used to find the best threshold giving good correspondence between the frequency of dry/wet spells in Hadley Centre regional model (HadRM3) output, reference observations with predetermined thresholds, and area-averaged observations. The analyses focus on selected model gridboxes in 3 different European climate regimes (Sweden, UK, Italy), where station data are available from several locations. In addition, a pan-European analysis using the European Climate Assessment (ECA) dataset is carried out. Generally, there is good agreement between point observations and the corresponding area average using the common thresholds of 0.1 or 1.0 mm with observational data. Applying the optimal thresholds on the model output is important, as it typically results in substantially better agreement between the simulated and observed series of dry/wet days. The fitted optimal pan-European dry/wet threshold is (1) 0.47 or 0.15 mm, depending on model version, for the observed point data threshold of 0.1 mm, and (2) 1.2 or 0.56 mm, depending on model version, for the threshold of 1.0 mm.

  • 8.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jonsson, P
    Achberger, C
    Ekstrom, M
    Alexandersson, Hans
    SMHI.
    The Lund instrumental record of meteorological observations: Reconstruction of monthly sea-level pressure 1780-19971999Ingår i: International Journal of Climatology, ISSN 0899-8418, E-ISSN 1097-0088, Vol. 19, nr 13, s. 1427-1443Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The reconstructed surface air pressure series from Lund, southern Sweden, covers the period 1780-1997 and comprises mon than 234000 valid observations (three observations per day), i.e. > 98% of all possible observation occasions. For the Early Instrumental Period (EIP; 1780-1860) data were digitised from the original records. For most of the Modern Instrumental Period (MIP; 1861-) a series was compiled from various databases containing instrument corrected data. During EIP, the series of raw monthly means show several substantial inhomogeneities. With the aid of a detailed reconstruction of the station history, it was possible to remove almost all inhomogeneities during EIP by applying the correct instrument corrections (for barometer temperature, to standard gravity and to mean sea-level pressure) to the series of original observations. In particular, corrections for the temperature and altitude of the barometer eliminated several inhomogeneities. A prerequisite for applying these corrections is the availability of high-resolution data (actual raw observations or daily averages). Further homogenisation was attained by intercomparison of the monthly mean pressure with acknowledged homogeneous series (mainly the UKMO monthly grid, station records from Copenhagen and Edinburgh). Statistical tests of homogeneity showed that no substantial inhomogeneities remain in the final version. The modern part of the final monthly pressure series largely follows that of the southern Baltic Sea region. Furthermore, it shows relatively high pressure during spring (MAM) in the period 1780-1820, which was paralleled by severe wind erosion in southern Scandinavia during this time. Relatively high pressure throughout the year is also notable during a period of precipitation deficit in 1970s. Copyright (C) 1999 Royal Meteorological Society.

  • 9.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Persson, Gunn
    SMHI, Affärsverksamhet.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Samuelsson, Patrick
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Evaluation of climate extremes in transient runs with the new Rossby Centre regional atmospheric model.2006Ingår i: Abstracts of the contributions of the EGU General Assembly 2006, EGU06-A-10110, 2006Konferensbidrag (Övrigt vetenskapligt)
  • 10.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Does the projected pathway to global warming targets matter?2018Ingår i: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 13, nr 2, artikel-id 024029Artikel i tidskrift (Refereegranskat)
  • 11.
    Bärring, Lars
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    von Storch, H
    Scandinavian storminess since about 18002004Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 31, nr 20, artikel-id L20202Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We study the history of storminess in Northern Europe, as derived from local pressure observations in Lund since 1780 and Stockholm since 1820 ( Sweden). At both stations barometer readings were made three times per day, morning, midday and evening, and after about 1850 at fixed observation hours. We use four common storminess indices: annual number of deep lows ( p < 980 hPa), the annual 95th and 99th percentile of pressure changes between two observations, and the annual number of fast absolute pressure changes (\&UDelta;p\/&UDelta;t > 16 hPa/12 h). It turns out that the 1980' s - mid 1990' s were a period of enhanced storminess, mainly seen in the Stockholm record, but his period is within the natural variability of the records. Thus, there are no robust signs of any long-term trend in the storminess indices. Storminess is during the entire historical period remarkably stable, with no systematic change and little transient variability.

  • 12. Deandreis, Celine
    et al.
    Page, Christian
    Braconnot, Pascale
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bucchignani, Edoardo
    de Cerff, Wim Som
    Hutjes, Ronald
    Joussaume, Sylvie
    Mares, Constantin
    Planton, Serge
    Plieger, Maarten
    Towards a dedicated impact portal to bridge the gap between the impact and climate communities: Lessons from use cases2014Ingår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 125, nr 3-4, s. 333-347Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Future climate evolution is of primary importance for the societal, economical, political orientations and decision-making. It explains the increasing use of climate projections as input for quantitative impact studies, assessing vulnerability and defining adaptation strategies in different sectors. Here we analyse 17 national and representative use cases so as to identify the diversity of the demand for climate information depending on user profiles as well as the best practices, methods and tools that are needed to answer the different requests. A particular emphasis is put on the workflow that allows to translate climate data into suitable impact data, the way to deal with the different sources of uncertainty and to provide a suited product to users. We identified three complementary tools to close the gap between climate scientists and user needs: an efficient interface between users and providers; an optimized methodology to handle user requests and a portal to facilitate access to data and elaborated products. We detail in the paper how these three tools can limit the intervention of experts, educate users, and lead to the production of useful information. This work provides the basis on which the ENES (European Network for Earth System Modelling) Portal Interface for the Climate Impact Communities is built.

  • 13. Good, P.
    et al.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Giannakopoulos, C.
    Holt, T.
    Palutikof, J.
    Non-linear regional relationships between climate extremes and annual mean temperatures in model projections for 1961-2099 over Europe2006Ingår i: Climate Research (CR), ISSN 0936-577X, E-ISSN 1616-1572, Vol. 31, nr 1, s. 19-34Artikel i tidskrift (Refereegranskat)
  • 14. Hanson, C. E.
    et al.
    Palutikof, J. P.
    Livermore, M. T. J.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bindi, M.
    Corte-Real, J.
    Durao, R.
    Giannakopoulos, C.
    Good, P.
    Holt, T.
    Kundzewicz, Z.
    Leckebusch, G. C.
    Moriondo, M.
    Radziejewski, M.
    Santos, J.
    Schlyter, P.
    Schwarb, M.
    Stjernquist, I.
    Ulbrich, U.
    Modelling the impact of climate extremes: an overview of the MICE project2007Ingår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 81, s. 163-177Artikel i tidskrift (Refereegranskat)
  • 15. Jacob, Daniela
    et al.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Christensen, Ole Bossing
    Christensen, Jens Hesselbjerg
    de Castro, Manuel
    Deque, Michel
    Giorgi, Filippo
    Hagemann, Stefan
    Hirschi, Martin
    Jones, Richard
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Lenderink, Geert
    Rockel, Burkhardt
    Sanchez, Enrique
    Schaer, Christoph
    Seneviratne, Sonia I.
    Somot, Samuel
    van Ulden, Aad
    van den Hurk, Bart
    An inter-comparison of regional climate models for Europe: model performance in present-day climate2007Ingår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 81, s. 31-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The analysis of possible regional climate changes over Europe as simulated by 10 regional climate models within the context of PRUDENCE requires a careful investigation of possible systematic biases in the models. The purpose of this paper is to identify how the main model systematic biases vary across the different models. Two fundamental aspects of model validation are addressed here: the ability to simulate (1) the long-term (30 or 40 years) mean climate and (2) the inter-annual variability. The analysis concentrates on near-surface air temperature and precipitation over land and focuses mainly on winter and summer. In general, there is a warm bias with respect to the CRU data set in these extreme seasons and a tendency to cold biases in the transition seasons. In winter the typical spread (standard deviation) between the models is 1 K. During summer there is generally a better agreement between observed and simulated values of inter-annual variability although there is a relatively clear signal that the modeled temperature variability is larger than suggested by observations, while precipitation variability is closer to observations. The areas with warm (cold) bias in winter generally exhibit wet (dry) biases, whereas the relationship is the reverse during summer (though much less clear, coupling warm (cold) biases with dry (wet) ones). When comparing the RCMs with their driving GCM, they generally reproduce the large-scale circulation of the GCM though in some cases there are substantial differences between regional biases in surface temperature and precipitation.

  • 16. Jonsson, A. M.
    et al.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Ensemble analysis of frost damage on vegetation caused by spring backlashes in a warmer Europe2011Ingår i: Natural hazards and earth system sciences, ISSN 1561-8633, E-ISSN 1684-9981, Vol. 11, nr 2, s. 401-418Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tree dehardening and budburst will occur earlier in a warmer climate, and this could lead to an increased risk of frost damage caused by temperature backlashes. By using a spring backlash index and a cold hardiness model, we assessed different aspects of risk for frost damage in Norway spruce forests during the present climate and for one future emission scenario. Uncertainties associated with climate modelling were quantified by using temperature data from three climate data sets: (1) E-Obs gridded observed climate data, (2) an ensemble of data from eight regional climate models (RCM) forced by ERA-40 reanalysis data, (3) an ensemble of regional climate scenarios produced by the regional climate model RCA3 driven at the boundary conditions by seven global climate models (GCM), all representing the SRES A1B emission scenario. The frost risk was analysed for three periods, 1961-1990, 2011-2040 and 2070-2097. The RCA3 GCM ensemble indicated that the risk for spring frost damage may increase in the boreo-nemoral forest zone of southern Scandinavia and the Baltic states/Belarus. This is due to an increased frequency of backlashes, lower freezing temperatures after the onset of the vegetation period and the last spring frost occurring when the trees are closer to budburst. The changes could be transient due to the fine balance between an increased risk of frost damage caused by dehardening during a period when freezing temperatures are common and a decreased risk caused by warmer temperatures. In the nemoral zone, the zone with highest risk for spring backlashes during the reference period (1961-1990), the spring frost severity may increase due to frost events occurring when the trees are closer to budburst. However, the risk in terms of frequency of backlashes and freezing temperature were projected to become lower already in the beginning of this century.

  • 17. Jonsson, A. M.
    et al.
    Eklundh, L.
    Hellstrom, M.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jonsson, P.
    Annual changes in MODIS vegetation indices of Swedish coniferous forests in relation to snow dynamics and tree phenology2010Ingår i: Remote Sensing of Environment, ISSN 0034-4257, E-ISSN 1879-0704, Vol. 114, nr 11, s. 2719-2730Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Remote sensing provides spatially and temporally continuous measures of forest reflectance, and vegetation indices calculated from satellite data can be useful for monitoring climate change impacts on forest tree phenology. Monitoring of evergreen coniferous forest is more difficult than monitoring of deciduous forest, as the new buds only account for a small proportion of the green biomass, and the shoot elongation process is relatively slow. In this study, we have analyzed data from 186 coniferous monitoring sites in Sweden covering boreal, southern-boreal, and boreo-nemoral conditions. Our objective was to examine the possibility to track seasonal changes in coniferous forests by time-series of MODIS eight-day vegetation indices, testing the coherence between satellite monitored vegetation indices (VI) and temperature dependent phenology. The relationships between two vegetation indices (NDVI and WDRVI) and four phenological indicators (length of snow season, modeled onset of vegetation period, tree cold hardiness level and timing of budburst) were analyzed. The annual curves produced by two curve fitting methods for smoothening of seasonal changes in NDVI and WDRVI were to a large extent characterized by the occurrence of snow, producing stable seasonal oscillations in the northern part and irregular curves with less pronounced annual amplitude in the southern part of the country. Measures based on threshold values of the VI-curves, commonly used for determining the timing of different phenological phases, were not applicable for Swedish coniferous forests. Evergreen vegetation does not have a sharp increase in greenness during spring, and the melting of snow can influence the vegetation indices at the timing of bud burst in boreal forests. However, the interannual variation in VI-values for specific eight-day periods was correlated with the phenological indicators. This relation can be used for satellite monitoring of potential climate change impacts on northern coniferous spring phenology. (C) 2010 Elsevier Inc. All rights reserved.

  • 18. Jonsson, Anna Maria
    et al.
    Appelberg, Gustaf
    Harding, Susanne
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Spatio-temporal impact of climate change on the activity and voltinism of the spruce bark beetle, Ips typographus2009Ingår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 15, nr 2, s. 486-499Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The spruce bark beetle Ips typographus is one of the major insect pests of mature Norway spruce forests. In this study, a model describing the temperature-dependent thresholds for swarming activity and temperature requirement for development from egg to adult was driven by transient regional climate scenario data for Sweden, covering the period of 1961-2100 for three future climate change scenarios (SRES A2, A1B and B2). During the 20th century, the weather supported the production of one bark beetle generation per year, except in the north-western mountainous parts of Sweden where the climate conditions were too harsh. A warmer climate may sustain a viable population also in the mountainous part; however, the distributional range of I. typographus may be restricted by the migration speed of Norway spruce. Modelling suggests that an earlier timing of spring swarming and fulfilled development of the first generation will significantly increase the frequency of summer swarming. Model calculations suggest that the spruce bark beetle will be able to initiate a second generation in South Sweden during 50% of the years around the mid century. By the end of the century, when temperatures during the bark beetle activity period are projected to have increased by 2.4-3.8 degrees C, a second generation will be initiated in South Sweden in 63-81% of the years. The corresponding figures are 16-33% for Mid Sweden, and 1-6% for North Sweden. During the next decades, one to two generations per year are predicted in response to temperature, and the northern distribution limit for the second generation will vary. Our study addresses questions applicable to sustainable forest management, suggesting that adequate countermeasures require monitoring of regional differences in timing of swarming and development of I. typographus, and planning of control operations during summer periods with large populations of bark beetles.

  • 19. Jonsson, Anna Maria
    et al.
    Harding, Susanne
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Ravn, Hans Peter
    Impact of climate change on the population dynamics of Ips typographus in southern Sweden2007Ingår i: Agricultural and Forest Meteorology, ISSN 0168-1923, E-ISSN 1873-2240, Vol. 146, nr 1-2, s. 70-81Artikel i tidskrift (Refereegranskat)
  • 20. Jönsson, Anna-Maria
    et al.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Future climate impact on spruce bark beetle life cycle in relation to uncertainties in regional climate model data ensembles2011Ingår i: Tellus. Series A, Dynamic meteorology and oceanography, ISSN 0280-6495, E-ISSN 1600-0870, s. 158-173Artikel i tidskrift (Refereegranskat)
  • 21.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Evaluating the method of pattern-scaling in time2006Konferensbidrag (Övrigt vetenskapligt)
  • 22.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Gollvik, Stefan
    Meterologi.
    Hansson, Ulf
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jones, Colin
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Samuelsson, Patrick
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Ullerstig, Anders
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Willén, Ulrika
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Wyser, Klaus
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    A 140-year simulation of European climate with the new version of the Rossby Centre regional atmospheric climate model (RCA3)2005Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report presents the latest version of the Rossby Centre regional atmospheric model, RCA3, with focus on model improvements since the earlier version, RCA2. The main changes in RCA3 relate to the treatment of land surface processes. Apart from the changes in land surface parameterizations several changes in the calculation of radiation, clouds, condensate and precipitation have been made. The new parameterizations hold a more realistic description of the climate system.Simulated present day climate is evaluated compared to observations. The new model version show equally good, or better, correspondence to observational climatologies as RCA2, when forced by perfect boundary conditions. Seasonal mean temperature errors are generally within ±1oC except during winter in north-western Russia where a larger positive bias is identified. Both the diurnal temperature range and the annual temperature range are found to be underestimated in the model. Precipitation biases are generally smaller than in the corresponding reanalysis data used as boundary conditions, showing the benefit of a higher horizontal resolution.The model is used for the regionalization of two transient global climate change projections for the time period 1961- 2100. The radiative forcing of the climate system is based on observed concentrations of greenhouse gases until 1990 and on the IPCC SRES B2 and A2 emissions scenarios for the remaining time period. Long-term averages as well as measures of the variability around these averages are presented for a number of variables including precipitation and near-surface temperature. It is shown that the changes in variability sometimes differ from the changes in averages. For instance, in north-eastern Europe, the mean increase in wintertime temperatures is followed by an even stronger reduction in the number of very cold days in winter. This kind of performance of the climate system implies that methods of inferring data from climate change projections to other periods than those actually simulated have to be used with care, at least when it comes to variables that are expected to change in a non-linear way. Further, these new regional climate change projections address the whole 21st century.

  • 23.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jacob, Daniela
    Jones, Richard
    Lenderink, Geert
    Schaer, Christoph
    Modelling daily temperature extremes: recent climate and future changes over Europe2007Ingår i: Climatic Change, ISSN 0165-0009, E-ISSN 1573-1480, Vol. 81, s. 249-265Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Probability distributions of daily maximum and minimum temperatures in a suite of ten RCMs are investigated for (1) biases compared to observations in the present day climate and (2) climate change signals compared to the simulated present day climate. The simulated inter-model differences and climate changes are also compared to the observed natural variability as reflected in some very long instrumental records. All models have been forced with driving conditions from the same global model and run for both a control period and a future scenario period following the A2 emission scenario from IPCC. We find that the bias in the fifth percentile of daily minimum temperatures in winter and at the 95th percentile of daily maximum temperature during summer is smaller than 3 (+/- 5 degrees C) when averaged over most (all) European sub-regions. The simulated changes in extreme temperatures both in summer and winter are larger than changes in the median for large areas. Differences between models are larger for the extremes than for mean temperatures. A comparison with historical data shows that the spread in model predicted changes in extreme temperatures is larger than the natural variability during the last centuries.

  • 24.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nilsson, Carin
    Lunds Universitet.
    Persson, Gunn
    SMHI, Affärsverksamhet.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Production and use of regional climate model projections – A Swedish perspective on building climate services2016Ingår i: Climate Services, ISSN 2405-8807, nr 2-3, s. 15-29Artikel i tidskrift (Refereegranskat)
  • 25.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Climate change in the Baltic Sea area in an ensemble of regional climate model simulations2010Konferensbidrag (Övrigt vetenskapligt)
  • 26.
    Kjellström, Erik
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Hansson, Ulf
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Ullerstig, Anders
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    An ensemble of regional climate change simulations2009Ingår i: / [ed] Rockel, B., Bärring, L and Reckermann, M., 2009, s. 134-135Konferensbidrag (Övrigt vetenskapligt)
  • 27. Krueger, Oliver
    et al.
    Feser, Frauke
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kaas, Eigil
    Schmith, Torben
    Tuomenvirta, Heikki
    von Storch, Hans
    Comment on "Trends and low frequency variability of extra-tropical cyclone activity in the ensemble of twentieth century reanalysis" by Xiaolan L. Wang, Y. Feng, G. P. Compo, V. R. Swail, F. W. Zwiers, R. J. Allan, and P. D. Sardeshmukh, Climate Dynamics, 20122014Ingår i: Climate Dynamics, ISSN 0930-7575, E-ISSN 1432-0894, Vol. 42, nr 3-4, s. 1127-1128Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    The main subject of this article is to comment on the issue of storminess trends derived from the twentieth century reanalysis (20CR) and from observations in the North Atlantic region written about in Wang et al. (Clim Dyn 40(11-12):2775-2800, 2012). The statement that the 20CR estimates would be consistent with storminess derived from pressure-based proxies does not hold for the time prior to 1950.

  • 28. Mair, Louise
    et al.
    Harrison, Philip J.
    Raty, Minna
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Snäll, Tord
    Forest management could counteract distribution retractions forced by climate change2017Ingår i: Ecological Applications, ISSN 1051-0761, E-ISSN 1939-5582, Vol. 27, nr 5, s. 1485-1497Artikel i tidskrift (Refereegranskat)
  • 29. Mair, Louise
    et al.
    Jonsson, Mari
    Raty, Minna
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Lamas, Tomas
    Snall, Tord
    Land use changes could modify future negative effects of climate change on old-growth forest indicator species2018Ingår i: Diversity & distributions: A journal of biological invasions and biodiversity, ISSN 1366-9516, E-ISSN 1472-4642, Vol. 24, nr 10, s. 1416-1425Artikel i tidskrift (Refereegranskat)
  • 30.
    Meier, Markus
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Christensen, Ole Bössing
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Lorenz, Philip
    Rockel, Burkhardt
    Zorita, Eduardo
    Selected examples of the added value of regional climate models2009Ingår i: / [ed] Rockel, B., Bärring, L and Reckermann, M., 2009, s. 54-55Konferensbidrag (Övrigt vetenskapligt)
  • 31.
    Nikulin, Grigory
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Changes in daily temperature variability over Europe from an ensemble of RCM simulations driven by several AOGCMs2009Konferensbidrag (Övrigt vetenskapligt)
  • 32.
    Nikulin, Grigory
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Changes in daily temperature variability over Europe from an ensemble of regional climate simulations driven by several AOGCMs.2009Konferensbidrag (Övrigt vetenskapligt)
  • 33.
    Nikulin, Grigory
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Intraseasonal temperature variability over Europe in a future climate scenario2008Ingår i: Abstracts of the contributions of the EGU General Assembly 2008., 2008, Vol. 10, artikel-id EGU2008-A-09248Konferensbidrag (Övrigt vetenskapligt)
  • 34.
    Nikulin, Grigory
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Projected changes in daily temperature variability over Europe in an ensemble of RCM simulations2009Konferensbidrag (Övrigt vetenskapligt)
  • 35. Nilsson, C.
    et al.
    Goyette, S.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Relating forest damage data to the wind field from high-resolution RCM simulations: Case study of Anatol striking Sweden in December 19992007Ingår i: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 57, nr 1-2, s. 161-176Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Forestry is of major economical importance in Europe, and recent devastating windstorms have pinpointed the vulnerability of this economic sector to windstorms. Forest damage is an important economic issue at a country level and may become even of larger concern under future conditions following global warming. An underlying question is to what extent the storm damage is due to changes in the wind climate compared to the effect of changes in forest management practices? In this paper, the first part of this rather complex problem is tackled. By using the Canadian Regional Climate Model, CRCM, including a physically based gust parameterisation scheme, NCEPNCAR reanalysis wind fields for the windstorm Anatol, on December 3-4, 1999, were downscaled, into a nested set-up, to 2 km resolution. The aim is to relate the simulated storm wind field to the observed distribution of storm damaged forests in Scania in southern Sweden, as a first methodological step towards analysing the effect of future windstorms in Swedish forests at the highest spatial resolution one can afford nowadays. Our results show that the CRCM produced realistic wind field simulations, compared to station observations, of the windstorm event in 1999. The simulated winds were underestimated at the coasts, but in congruence with inland observations. Most of the damaged forest stands were located on south-westerly (SW) slopes, which indicated a south-westerly wind during the wind throw process. This SW wind direction was evident in the early phase of the simulated storm, but then changed into a westerly flow, at an earlier stage than the true observations specified. Further, most damage occurred in the areas of simulated maximum wind speed greater than 30 m s. To conclude, the CRCM has proven to be a useful tool to realistically simulate a forest damaging storm event. Hence, the model could be used for further study cases, preferably driven by a GCM, in order to reveal a greater understanding about recent storms, which in turn helps us evaluate future climate change driven storm conditions. (c) 2006 Elsevier B.V All rights reserved.

  • 36.
    Persson, Gunn
    et al.
    SMHI, Affärsverksamhet.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Rummukainen, Markku
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Climate indices for vulnerability assessments2007Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Behovet av information om klimatets förändring och dess effekter på olika regioner och sektorer ökar stadigt. För att belysa frågeställningar runt klimatets utveckling, dess påverkan och behov av anpassning behövs projektioner av framtidens klimat. Den generella kunskapen om klimat baseras oftast på erfarenhet av tidigare klimat, väderobservationer, prognoser och återanalyser av historiska data. För att hantera framtidens föränderliga klimat behöver vi utveckla metoder för att förfina användningen av information från klimatmodeller. Klimatindex, formulerade med avnämarperspektiv i fokus och beräknade utifrån data från klimatmodeller, är ett sätt att kommunicera den komplexa frågan om effekter av klimatets framtida utveckling. Klimatindex kan vara välkänd information som summerad nederbörd eller medeltemperaturer men kan också beskriva mer komplexa relationer och då innefatta till exempel tröskelvärden eller exponeringstid för olika förhållanden. I denna rapport beskrivs ett omfattande material av klimatindex baserade på beräkningar med två regionala klimatmodeller utifrån olika utsläppsscenarier och globala klimatmodeller. Materialet har legat till grund för arbetet inom den svenska Klimat- och sårbarhetsutredningen (M2005:03), men har även framtagits i samarbete med andra avnämargrupper. De flesta klimatmodeller och klimatscenarier som ligger till grund för indexberäkningarna har tidigare dokumenterats i andra rapporter men ges här en övergripande beskrivning. Till rapporten bifogas en DVD med det omfattande kartmaterial som illustrerar indexberäkningarna och tillhörande information. Materialet finns även tillgängligt på www.smhi.se.

  • 37.
    Persson, Gunn
    et al.
    SMHI, Affärsverksamhet.
    Strandberg, Gustav
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Beräknade temperaturförhållanden för tre platser i Sverige – perioderna 1961-1990 och 2011-20402007Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Under hösten 2006 utförde Rossby Centre ett omfattande arbete för att till olika sektorer i samhället ta fram underlagsmaterial om klimatets utveckling. Beställare var framförallt Klimat- och sårbarhetsutredningens olika arbetsgrupper men också energibranschen. Föreliggande rapport beskriver en delleverans till Elforsk-projektet ”Tänkbara konsekvenser för den svenska energisektorn av klimatförändringar – effekter, sårbarhet och anpassning”. Material togs fram som belyser en möjlig temperaturutveckling i ett relativt kort framtidsperspektiv representerat av perioden 2011-2040. Det fanns önskemål om att särskilt titta på utvecklingen för tre platser med olika klimat i ett nord-sydligt perspektiv och med närhet till större befolkningsgrupper.Analyserna inom projektet har finansierats av Elforsk. Modellsimuleringarna har gjorts på den dedikerade klimatdatorresursen ”Tornado” vid Nationellt Superdatorcentrum, Linköpings universitet. Tornado finansieras av Knut och Alice Wallenbergs Stiftelse.I denna rapport presenteras materialet avseende de tre platserna kompletterat med ett litet urval kartor som visar några temperaturindex. Ett mycket omfattande kartmaterial finns att tillgå på Rossby Centrets hemsida som nås via www.smhi.se.

  • 38. Pisinaras, Vassilios
    et al.
    Yang, Wei
    SMHI, Forskningsavdelningen, Hydrologi.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Gemitzi, Alexandra
    Conceptualizing and assessing the effects of installation and operation of photovoltaic power plants on major hydrologic budget constituents2014Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 493, s. 239-250Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study addresses the effects of land use change from agricultural to photovoltaic parks (PVPs) on the hydrology of an area. Although many environmental effects have been identified and analyzed, only minor attention has been given to the hydrologic effects of the installation and operation of PVPs. The effects of current PVP installation and operation practices on major hydrologic budget constituents (surface runoff, evapotranspiration and percolation) were identified, conceptualized, quantified and simulated using SWAT model. Vosvozis river basin located in north Greece was selected as a test site. Additionally, long-term effects were simulated using dynamically downscaled climate projections by a Regional Climate Model (RCM) driven by 5 different General Circulation Models (GCMs) for the period 2011-2100. Results indicate that surface runoff and percolation potential are significantly increased at the local scale and have to be considered during PVP siting, especially when sensitive and protected ecosystems are involved. (C) 2014 Elsevier B.V. All rights reserved.

  • 39. Pulatov, Bakhtiyor
    et al.
    Jonsson, Anna Maria
    Wilcke, Renate
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Linderson, Maj-Lena
    Hall, Karin
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Evaluation of the phenological synchrony between potato crop and Colorado potato beetle under future climate in Europe2016Ingår i: Agriculture, Ecosystems & Environment, ISSN 0167-8809, E-ISSN 1873-2305, Vol. 224, s. 39-49Artikel i tidskrift (Refereegranskat)
  • 40. Rammig, A.
    et al.
    Jonsson, A. M.
    Hickler, T.
    Smith, B.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Sykes, M. T.
    Impacts of changing frost regimes on Swedish forests: Incorporating cold hardiness in a regional ecosystem model2010Ingår i: Ecological Modelling, ISSN 0304-3800, E-ISSN 1872-7026, Vol. 221, nr 2, s. 303-313Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Understanding the effects of climate change on boreal forests which hold about 7% of the global terrestrial biomass carbon is a major issue. An important mechanism in boreal tree species is acclimatization to seasonal variations in temperature (cold hardiness) to withstand low temperatures during winter. Temperature drops below the hardiness level may cause frost damage. Increased climate variability under global and regional warming might lead to more severe frost damage events, with consequences for tree individuals, populations and ecosystems. We assessed the potential future impacts of changing frost regimes on Norway spruce (Picea abies L. Karst.) in Sweden. A cold hardiness and frost damage model were incorporated within a dynamic ecosystem model, LPJ-GUESS. The frost tolerance of Norway spruce was calculated based on daily mean temperature fluctuations, corresponding to time and temperature dependent chemical reactions and cellular adjustments. The severity of frost damage was calculated as a growth-reducing factor when the minimum temperature was below the frost tolerance. The hardiness model was linked to the ecosystem model by reducing needle biomass and thereby growth according to the calculated severity of frost damage. A sensitivity analysis of the hardiness model revealed that the severity of frost events was significantly altered by variations in the hardening rate and dehardening rate during current climate conditions. The modelled occurrence and intensity of frost events was related to observed crown defoliation, indicating that 6-12% of the needle loss could be attributed to frost damage. When driving the combined ecosystem-hardiness model with future climate from a regional climate model (RCM), the results suggest a decreasing number and strength of extreme frost events particularly in northern Sweden and strongly increasing productivity for Norway spruce by the end of the 21st century as a result of longer growing seasons and increasing atmospheric CO(2) concentrations. However, according to the model, frost damage might decrease the potential productivity by as much as 25% early in the century. (C) 2009 Elsevier B.V. All rights reserved.

  • 41. Ruete, Alejandro
    et al.
    Yang, Wei
    SMHI, Forskningsavdelningen, Hydrologi.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Stenseth, Nils Chr.
    Snall, Tord
    Disentangling effects of uncertainties on population projections: climate change impact on an epixylic bryophyte2012Ingår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 279, nr 1740, s. 3098-3105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Assessment of future ecosystem risks should account for the relevant uncertainty sources. This means accounting for the joint effects of climate variables and using modelling techniques that allow proper treatment of uncertainties. We investigate the influence of three of the IPCC's scenarios of greenhouse gas emissions (special report on emission scenarios (SRES)) on projections of the future abundance of a bryophyte model species. We also compare the relative importance of uncertainty sources on the population projections. The whole chain global climate model (GCM)-regional climate model-population dynamics model is addressed. The uncertainty depends on both natural-and model-related sources, in particular on GCM uncertainty. Ignoring the uncertainties gives an unwarranted impression of confidence in the results. The most likely population development of the bryophyte Buxbaumia viridis towards the end of this century is negative: even with a low-emission scenario, there is more than a 65 per cent risk for the population to be halved. The conclusion of a population decline is valid for all SRES scenarios investigated. Uncertainties are no longer an obstacle, but a mandatory aspect to include in the viability analysis of populations.

  • 42.
    Rummukainen, Markku
    et al.
    SMHI, Samhälle och säkerhet.
    Rockel, Burkhardt
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Christensen, Jens Hesselbjerg
    Reckermann, Marcus
    Twenty-First-Century Challenges in Regional Climate Modeling2015Ingår i: Bulletin of The American Meteorological Society - (BAMS), ISSN 0003-0007, E-ISSN 1520-0477, Vol. 96, nr 8, s. ES135-ES138Artikel i tidskrift (Refereegranskat)
  • 43.
    Rutgersson, Anna
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jaagus, Jaak
    Schenk, Frederik
    Stendel, Martin
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Briede, Agrita
    Claremar, Bjorn
    Hanssen-Bauer, Inger
    Holopainen, Jari
    Moberg, Anders
    Nordli, Oyvind
    Rimkus, Egidijus
    Wibig, Joanna
    Recent Change-Atmosphere2015Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    This chapter describes observed changes in atmospheric conditions in the Baltic Sea drainage basin over the past 200-300 years. The Baltic Sea area is relatively unique with a dense observational network covering an extended time period. Data analysis covers an early period with sparse and relatively uncertain measurements, a period with well-developed synoptic stations, and a final period with 30+ years of satellite data and sounding systems. The atmospheric circulation in the European/Atlantic sector has an important role in the regional climate of the Baltic Sea basin, especially the North Atlantic Oscillation. Warming has been observed, particularly in spring, and has been stronger in the northern regions. There has been a northward shift in storm tracks, as well as increased cyclonic activity in recent decades and an increased persistence of weather types. There are no long-term trends in annual wind statistics since the nineteenth century, but much variation at the (multi-)decadal timescale. There are also no long-term trends in precipitation, but an indication of longer precipitation periods and possibly an increased risk of extreme precipitation events.

  • 44.
    Strandberg, Gustav
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Hansson, Ulf
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jansson, Christer
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Jones, Colin
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kupiainen, Marco
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Samuelsson, Patrick
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Ullerstig, Anders
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    CORDEX scenarios for Europe from the Rossby Centre regional climate model RCA42015Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Denna rapport dokumenterar klimatmodellsimuleringar på 50 km horisontell upplösning över Europa med Rossby Centres regionala atmosfärsmodell (RCA4) gjorda inom projektet Coordinated Regional Downscaling Experiment (CORDEX) för i) ERAInterim-drivna (ERAINT) simuleringar för att utvärdera förmågan hos RCA4 att simuleraden senaste tidens klimat, ii) historiska simuleringar av de senaste årtiondena med drivning från nio olika globala klimatmodeller (GCM:er) och iii) framtidsscenarierna RCP 4,5 och RCP 8,5 drivna med samma GCM:er. Dessa simuleringar representerar en delmängd av alla CORDEX-simuleringar producerade vid Rossby Centre och en allmän slutsats dragen vid Rossby Centre är att en sådan ensemble inte varit möjlig utan att först etablera den effektiva produktionskedja som beskrivs här. Första delen av rapporten dokumenterar RCA4 och dess förmåga i en simulering där ERAINT skalades ner. RCA4 återskapar till stor del den storskaliga cirkulationen från ERAINT, men några lokala avvikelser förekommer. I allmänhet simuleras säsongscykler för temperatur och nederbörd i överensstämmelse med observationer. Några avvikelser finns, som för mycket nederbörd i norra Europa och för lite i södra. På vintern är det även för mycket nederbörd i östra Europa. Temperaturen är i allmänhet underskattad i norra Europa och i medelhavsområdet på vintern, medan för höga temperaturer ges i sydöstra Europa på vintern och i medelhavsområdet på sommaren. RCA4 presterar i allmänhet bra i simuleringar av den senaste tidens klimat med randvillkor från GCM:er. En stor del av det simulerade klimatet i RCA4 kan tillskrivas den drivande GCM:en, men RCA4 skapar sitt eget klimat inuti modelldomänen och lägger till detaljer på grund av högre upplösning. Alla nio nedskalade GCM:er har gemensamma problem i representationen av den storskaliga cirkulationen på vintern. Denna egenskap förs vidare till RCA4. Avvikelserna i storskalig cirkulation medför avvikelser i temperatur och nederbörd i RCA4. Klimatförändringssignalen som den simuleras av RCA4-ensembler enligt RCP 4,5 och RCP 8,5 är mycket lika tidigare resultat. I både scenario RCP 4,5 och RCP 8,5 beräknas Europa bli varmare i framtiden. På vintern är uppvärmningen störst i norra Europa, och på sommaren i södra Europa. Den högsta dygnsmedeltemperaturen på sommaren ökar på ungefär samma sätt som sommartemperaturen, men något mer i södra Europa. Den lägsta dygnsmedeltemperaturen på vintern i norra Europa är den temperatur som förändras mest. Nederbörden beräknas öka under alla årstider i norra Europa och minska i södra Europa. Den största dygnsnederbörden (och per sjudagarsperiod) beräknas öka i nästan hela Europa och i alla årstider. Samtidigt beräknas den längsta perioden utan nederbörd att bli längre i södra Europa. I allmänhet förutses små förändringar i medelvindhastighet. Det finns emellertid områden med signifikanta förändringar i vind. Att använda ensembler är ett sätt att beskriva osäkerheterna i scenarierna, men det finns andra möjliga ensembler som använder andra modeller och som skulle ge andra resultat. Ändå anses den ensemble som används här vara tillräckligt lik dessa andra ensembler för att vara representativ för den hela mängden GCM:er. Dynamisk nedskalning med RCA4 förändrar klimatförändringssignalen, och spridningen i ensemblen minskar ibland, men ensemblen med nio RCA4 simuleringar med olika GCM:er anses vara representativ för den hela ensemblen. Alla scenarier är överens om mönstret på klimatförändringen, men storleken på förändringen bestäms av valet av scenario. Den relativa betydelsen av valet av scenario ökar med tiden.

  • 45.
    Venäläinen, Ari
    et al.
    Finnish Meteorological Institute, Finland.
    Saku, Seppo
    Finnish Meteorological Institute, Finland.
    Jylhä, Kirsti
    Finnish Meteorological Institute, Finland.
    Nikulin, Grigory
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Kjellström, Erik
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Climate extremes and safety of nuclear power plants: Extreme temperatures and enthalpy in Finland and Sweden in a changing climate.2009Rapport (Övrigt vetenskapligt)
  • 46.
    Wern, Lennart
    et al.
    SMHI, Samhälle och säkerhet.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Sveriges vindklimat 1901-2008: Analys av trend i geostrofisk vind2009Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    En studie har gjorts hur vinden har varierat i Sverige under perioden 1901 - 2008. Eftersom det saknas långa homogena mätserier av vindhastighet i Sverige har vi utgått från tryckmätningar och beräknatden s.k. geostrofiska vinden i elva trianglar som täcker Sverige. Eftersom bara tre observationer per dag (morgon, middag och kväll) har funnits att tillgå så kan det ha blåst mer mellan observationerna.Ett stort arbete har lagts ner på att kontrollera och rätta felaktiga observationer. Mellan åren 1951 och 2008 har varje observerat värde jämförts med ett interpolerat värde. Om skillnaden varit mer än 4 - 5 hPa har en karta analyserats för att kunna avgöra om det i databasen lagrade värdet varit korrekt. Kanske tusen tryckkartor har analyserats. Även två närliggande stationers observationer har jämförts till exempel Bromma och Observatoriekullen. Före 1951 har granskningsarbetet varit begränsat eftersom digitaliserade data saknas för fler stationer än de som ingår i denna undersökning.Förändringen av vindklimatet i elva trianglar som täcker huvuddelen av Sverige har studerats medhjälp av flera olika mått, bland annat:- Årets högsta vindhastighet- Årets medelvindhastighet- Antal fall på minst 25 m/s under året- Potentiell vindenergi under åretÅrets högsta geostrofiska vindhastighet har även jämförts med högsta havsvattenstånd och skogsskador.I det studerade materialet inträffade den absolut högsta geostrofiska vindhastigheten den 13 januari 1984 i den sydligaste triangeln Göteborg - Visby - Lund. Då beräknades den geostrofiska vindhastigheten till 66 m/s och vindriktningen var 235°.Denna undersökning visar bland annat att:- Årets högsta vindhastighet har ökat i fem trianglar och minskat i sex trianglar sedan 1951. Den sammanvägde trenden i Sverige visar på en svag ökning som inte är statistiskt signifikant.- Antal tillfällen per år då vindhastigheten varit minst 25 m/s har minskat i sju av de elva trianglarna sedan 1951.- Medelvindhastigheten har minskat i tio av de elva trianglarna sedan 1951. För fyra trianglar i norra Sverige är denna minskning statistiskt signifikant. Sammantaget för Sverige har medelvindhastigheten minskat med 4 %.- På samma sätt har den potentiella vindenergin minskat i dessa tio trianglar sedan 1951-talet. Minskningen är statistiskt signifikant i de fyra nordliga trianglarna. Sammantaget för Sverige har energin minskat med 7 %.

  • 47.
    Wilcke, Renate
    et al.
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Bärring, Lars
    SMHI, Forskningsavdelningen, Klimatforskning - Rossby Centre.
    Selecting regional climate scenarios for impact modelling studies2016Ingår i: Environmental Modelling & Software, ISSN 1364-8152, E-ISSN 1873-6726, Vol. 78, s. 191-201Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In climate change research ensembles of climate simulations are produced in an attempt to cover the uncertainty in future projections. Many climate change impact studies face difficulties using the full number of simulations available, and therefore often only subsets are used. Until now such subsets were chosen based on their representation of temperature change or by accessibility of the simulations. By using more specific information about the needs of the impact study as guidance for the clustering of simulations, the subset fits the purpose of climate change impact research more appropriately. Here, the sensitivity of such a procedure is explored, particularly with regard to the use of different climate variables, seasons, and regions in Europe. While temperature dominates the clustering, the resulting selection is influenced by all variables, leading to the conclusion that different subsets fit different impact studies best. (C) 2016 The Authors. Published by Elsevier Ltd.

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