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  • 1351.
    Krysell, Mikael
    et al.
    SMHI, Samhälle och säkerhet.
    FOGELQVIST, E
    TANHUA, T
    APPARENT REMOVAL OF THE TRANSIENT TRACER CARBON-TETRACHLORIDE FROM ANOXIC SEAWATER1994Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 21, nr 23, s. 2511-2514Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Two chlorofluorocarbons (CFC-11 and carbon tetrachloride, CCl4) widely used as tracers for dating water masses, were measured in the Gotland Basin of the Baltic Sea. At the time of the survey, the bottom water of the basin had remained stagnant for 15 years and anoxic for about the same period of time, and the concentrations of both CFC-11 and CCl4 decrease dramatically with depth below the mixed layer. Furthermore, the ratio of CFC-11 to CCl4 increases with depth under the mixed layer along with a steep decrease in oxygen concentration. This is contrary to what would be expected from the atmospheric histories. The most plausible explanation for this is that there is a mechanism whereby the CCl4 is removed from the water mass under anoxic and suboxic conditions.

  • 1352.
    Bergström, Sten
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    Carlsson, Bengt
    SMHI, Forskningsavdelningen, Hydrologi.
    RIVER RUNOFF TO THE BALTIC SEA - 1950-19901994Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 23, nr 4-5, s. 280-287Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A database of monthly inflow of fresh water from rivers and land to the Baltic Sea and its subbasins is created. The database covers the period 1950-1990 and is based on observations from the national hydrological services of the surrounding countries. The main features of the database are presented including river flow of selected rivers and total inflow to the Baltic Sea and its subbasins. Long term, seasonal and short-term variabilities are analyzed and the effects of hydropower development are identified. An earlier database by Mikulski is used for comparison and extension of the record to cover the period 1921-1990. It is concluded that the variability of inflow is great and that the decade 1981-1990 was the wettest in 70 years. Wet years are also found in the 1920s. The increase in runoff is mainly due to increasing river flow during the cold seasons. The effects of hydropower development are noticeable in the records for the Bothnian Bay and the Bothnian Sea.

  • 1353.
    Håkansson, Bertil
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Moberg, Mats
    SMHI.
    THE ALGAL BLOOM IN THE BALTIC DURING JULY AND AUGUST 1991, AS OBSERVED FROM THE NOAA WEATHER-SATELLITES1994Ingår i: International Journal of Remote Sensing, ISSN 0143-1161, E-ISSN 1366-5901, Vol. 15, nr 5, s. 963-965Artikel i tidskrift (Refereegranskat)
  • 1354.
    Brandt, Maja
    et al.
    SMHI, Samhälle och säkerhet.
    Bergström, Sten
    SMHI, Forskningsavdelningen, Hydrologi.
    INTEGRATION OF FIELD DATA INTO OPERATIONAL SNOWMELT-RUNOFF MODELS1994Ingår i: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 25, nr 1-2, s. 101-112Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conceptual runoff models have become standard tools for operational hydrological forecasting in Scandinavia. These models are normally based on observations from the national climatological networks, but in mountainous areas the stations are few and sometimes not representative. Due to the great economic importance of good hydrological forecasts for the hydro-power industry attempts have been made to improve the model simulations by support from field observations of the snowpack. The snowpack has been mapped by several methods; airborne gamma-spectrometry, airborne georadars, satellites and by conventional snow courses. The studies cover more than ten years of work in Sweden. The conclusion is that field observations of the snow cover have a potential for improvement of the forecasts of inflow to the reservoirs in the mountainous part of the country, where the climatological data coverages is poor. This is pronounced during years with unusual snow distribution. The potential for model improvement is smaller in the climatologically more homogeneous forested lowlands, where the climatological network is denser. The costs of introduction of airborne observations into the modelling procedure are high and can only be justified in areas of great hydropower potential.

  • 1355. FRANZEN, LG
    et al.
    HJELMROOS, M
    Kållberg, Per
    SMHI, Forskningsavdelningen, Meteorologi.
    BRORSTROMLUNDEN, E
    JUNTTO, S
    SAVOLAINEN, AL
    THE YELLOW-SNOW EPISODE OF NORTHERN FENNOSCANDIA, MARCH-1991 - A CASE-STUDY OF LONG-DISTANCE TRANSPORT OF SOIL, POLLEN AND STABLE ORGANIC-COMPOUNDS1994Ingår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 28, nr 22, s. 3587-3604Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present paper describes a vast dustfall with snow in northern Fennoscandia, 10 March 1991. The area affected by dust deposition was at least 320,000 km(2). and the particulate mass received amounted to between 50 and 200 mg m(-2). The total amounts of dust deposited in the investigated area sum up to approximately 50,000 tonnes. The dust consisted of soil particles, i.e. single mineral grains and loose ferric aggregates of mineral grains in addition to pollen and spores. Mineralogically, the dust was dominated by small rounded quartz grains. Median size of the dust particles was 2.72 mu m. The total pollen concentration varied from 327 to 1172 pollen cm(-2). The pollen types identified were divided in ''Nordic/Central European'' taxa and ''Exotic'' taxa. Pollen from the former group, e.g. Betula, Alnus and Corylus were believed to originate in the Alps and in the northern parts of Central Europe where these species were flowering. The latter category was considered to originate in more remote areas, many of them belonging to the taxa growing only around the Mediterranean. From a paleo-ecological point of view, long-distance transport such as this would count for an important potential source of error whenever interpreting Holocene pollen diagrams. The content of stable organic compounds showed that the dust was relatively clean, compared to other episodes, when the dust deposited had originated in heavily polluted regions. The small amounts of chlorinated hydrocarbons, polychlorinated biphenyles (PCB), polyaromated hydrocarbons (PAH) and other hydrocarbons found, are believed to have been adsorbed by the particle surfaces during transportation. The results of the study, along with meteorological data, lead to the conclusion that the material originated in North Africa. Dust mobilization was reported in Tunisia as well as in Algeria. This means that the dust was transported at least 7000 km before deposition.

  • 1356.
    Liljas, Erik
    et al.
    SMHI, Samhälle och säkerhet.
    MURPHY, AH
    ANGSTROM,ANDERS AND HIS EARLY PAPERS ON PROBABILITY FORECASTING AND THE USE VALUE OF WEATHER FORECASTS1994Ingår i: Bulletin of The American Meteorological Society - (BAMS), ISSN 0003-0007, E-ISSN 1520-0477, Vol. 75, nr 7, s. 1227-1236Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Anders K. Angstrom was known primarily for his contributions to the field of atmospheric radiation. However, his scientific interests encompassed many diverse topics. This paper describes the contents of two early, remarkable, and, until recently, largely unknown papers by Angstrom on probability forecasting and the use/value of weather forecasts. These papers, entitled ''Sannolikhet och Praktisk Vaderleksprognos'' (''Probability and Practical Weather Forecasting'') and ''On the Effectivity of Weather Warnings, ''were published in 1919 and 1922, respectively. Noteworthy features of these two papers include 1) a discussion of the sources of uncertainty in weather forecasting, 2) discourses on the problems of estimating probabilities by means of empirical relative frequencies and forecasters' subjective judgments, 3) the use of a Gaussian model to describe the accuracy of minimum temperature forecasts, 4) the identification of the ratio of the protection costa to the ''risked value'' if protective action is not taken b as a characteristic of users of forecasts, 5) analytical expressions for the economic value of weather warnings, 6) quantitative analysis of the problems faced by forecasters in deciding whether or not to issue weather warnings when they are uncertain about future weather conditions, and 7) arguments concerning the need to obtain estimates of the costs and losses that may be incurred by potential users in order to assess economic effectiveness. The contents of Angstrom's two papers are reviewed and summarized, making extensive use of quotations from the texts. An effort is made to place the papers and their contents in proper historical context. Two topics of current interest, namely, ensemble forecasting and the provision of specialized weather services, are discussed briefly in light of the results presented and issues raised in these papers.

  • 1357.
    Andersson, Tage
    et al.
    SMHI, Forskningsavdelningen.
    Gustafsson, Nils
    SMHI, Forskningsavdelningen, Meteorologi.
    COAST OF DEPARTURE AND COAST OF ARRIVAL - 2 IMPORTANT CONCEPTS FOR THE FORMATION AND STRUCTURE OF CONVECTIVE SNOWBANDS OVER SEAS AND LAKES1994Ingår i: Monthly Weather Review, ISSN 0027-0644, E-ISSN 1520-0493, Vol. 122, nr 6, s. 1036-1049Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A case with intense convective snowbands over the Baltic Sea is examined using the High-Resolution Limited Area Model. The intention is to gain a better insight into the importance of the shape of the cowta, the orography, and the surface roughness on the formation and evolution of the snowbands. Among the factors studied am the shape of the coast from which the air departs and that to which it arrives. These factors are so important that two new concepts-coast of departure and coast of arrival-are introduced.

  • 1358. SJODIN, A
    et al.
    LOMAN, G
    Omstedt, Gunnar
    SMHI, Forskningsavdelningen, Luftmiljö.
    LONG-TERM CONTINUOUS MEASUREMENTS OF AIR POLLUTANT CONCENTRATIONS, METEOROLOGY AND TRAFFIC ON A RURAL MOTORWAY AND A MODEL VALIDATION1994Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 147, s. 365-375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Air concentrations of carbon monoxide (CO), nitrogen oxide (NO) and nitrogen dioxide (NO2) were continuously monitored at a rural motorway site in Sweden for the period February-December 1990. In addition, local meteorology and traffic parameters were measured in order to validate a dispersion model. Even close to the motorway, the concentrations of CO and NO2 were well below Swedish air quality guidelines. For long-term averages the regional background contributed significantly to the downwind levels. The atmospheric reaction between primary emitted NO and background ozone (O3) tends to be a major source of downwind NO2, also fairly close to the road (10 m from the road shoulder), where the average NO2/NO(x) ratio was approximately 0.4. The validated model employs a percentile analysis on the basis of the HIWAY-2 and CALINE4 models and a separate emission model. The agreement between measured and modelled data, as refered to the 98th percentile, was good for NO2 but moderate for CO. This is probably partly caused by uncertainties in emission factors for CO for heavy vehicles. Since a good agreement was observed between measured and calculated NO(x) concentrations, problems in adequately modelling NO2 are probably associated with uncertainties as to NO2/NO(x) ratios in the exhaust, or the modelling of the O3 reaction.

  • 1359.
    Marmefelt, Eleonor
    et al.
    SMHI, Affärsverksamhet.
    Omstedt, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    DEEP-WATER PROPERTIES IN THE GULF OF BOTHNIA1993Ingår i: Continental Shelf Research, ISSN 0278-4343, E-ISSN 1873-6955, Vol. 13, nr 2-3, s. 169-187Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The northern extension of the Baltic Sea, the Gulf of Bothnia, is a weakly stratified sea. One would therefore expect that the deep water of the Gulf is easily renewed through deep thermal convection, or even through deep haline convection, as the Gulf is more or less covered with ice every winter. However, the present study shows, through analysis of historical temperature, salinity and density data, that the deep water in the Gulf of Bothnia is mainly renewed by major inflows of Baltic Proper surface water. The penetrating water forms a dense bottom current in the Gulf. In the southern part of the Gulf, the Bothnian Sea, the volume flow of the bottom current is found to increase by 10%. It is therefore not likely that the bottom current properties are changed to any appreciable extent. The bottom current properties in the Bothnian Bay, on the other hand, are highly affected, as the volume flow is estimated to increase by 150% in this basin.

  • 1360.
    Andersson, Lars
    et al.
    SMHI, Samhälle och säkerhet.
    RYDBERG, L
    EXCHANGE OF WATER AND NUTRIENTS BETWEEN THE SKAGERRAK AND THE KATTEGAT1993Ingår i: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 36, nr 2, s. 159-181Artikel i tidskrift (Refereegranskat)
  • 1361.
    Robertson, Lennart
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    Persson, Christer
    SMHI, Forskningsavdelningen, Luftmiljö.
    ATTEMPTS TO APPLY 4-DIMENSIONAL DATA ASSIMILATION OF RADIOLOGICAL DATA USING THE ADJOINT TECHNIQUE1993Ingår i: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 50, nr 2-4, s. 333-337Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A data assimilation procedure is presented. By feeding measurements into a dispersion model. using the adjoint technique, it is shown that the proper transport level as well as the source intensity can he found. The technique is tested on a fictitious accidental release. and thus fictitious measurements are used.

  • 1362. ENGQVIST, A
    et al.
    Omstedt, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    WATER EXCHANGE AND DENSITY STRUCTURE IN A MULTIBASIN ESTUARY1992Ingår i: Continental Shelf Research, ISSN 0278-4343, E-ISSN 1873-6955, Vol. 12, nr 9, s. 1003-1026Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A mathematical model of the Himmerfjard estuary. divided into four basins. has been formulated and validated against measured data for 1986. The structure of each sub-basin is assumed to be horizontally homogeneous with vertical mean velocities based upon in- and outflows from adjacent basins and freshwater supply to each basin. The horizontal water exchange is formulated as a quasi-stationary Bernioulli flow, driven by horizontal pressure gradients over the sounds and instantaneously interleaved at a neutral buoyancy level. Thc salinity and temperature profiles measured outside the mouth of the estuary serve as forcing, as do the water level changes, the freshwater run-off and the local wind. Inherent in the model assumptions of the horizontal exchange over the sounds is that only a fraction, alpha, of the pressure gradient is used to accelerate each stratum. Variation of the alpha-value shows that the best statistical fit is found for alpha = 0.15 when compared with water exchange estimates based on measurements in one of the internal sounds tor almost an entire month. Using this alpha-value, in combination with standard mixing parameters and hypsographical data, the model satisfactorily captures the major features of the salinity and temperature-profiles development for the year 1986. This is substantiated by statistical analysis of the salinity profiles in the sub-basins for which different measures of similarity between simulated and measured data give the best fit for the same alpha-value as above.

  • 1363.
    Omstedt, Anders
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Svensson, Urban
    SMHI, Forskningsavdelningen, Oceanografi.
    ON THE MELT RATE OF DRIFTING ICE HEATED FROM BELOW1992Ingår i: Cold Regions Science and Technology, ISSN 0165-232X, E-ISSN 1872-7441, Vol. 21, nr 1, s. 91-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The melt rates of fresh and saline drifting ice, heated from below, are examined using a one-dimensional ice/ocean model with high vertical resolution. The model is based on the conservation equations for heat, salt, and momentum and uses turbulence models to achieve closure. The model includes a low-Reynolds number turbulence model for the viscous region, coupled to a high-Reynolds number turbulence model for the outer boundary, and a discrete element approach to the parameterization of roughness. It is shown that the melt rate of drifting ice is sensitive to ice roughness and molecular salt diffusion, and it is found that bulk heat transfer coefficients vary within a rather narrow range in the examined interval.

  • 1364.
    Omstedt, Anders
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    WETTLAUFER, JS
    ICE GROWTH AND OCEANIC HEAT-FLUX - MODELS AND MEASUREMENTS1992Ingår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 97, nr C6, s. 9383-9390Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Heat fluxes al the ice-ocean interface and ice thickness are investigated by comparing field data from the Coordinated Eastern Arctic Experiment (CEAREX) drift phase with model calculations. The calculations are based on two types of models. The first one is a one-dimensional ice-ocean model with high vertical resolution. This model is based on the conservation equations for heat, salt, and momentum and uses turbulence models to achieve closure. A discrete element approach is also introduced to explicitly parameterize the ice roughness. The second model is a simple one-dimensional bulk heat transfer model. In this version, the interfacial salinity is modelled on the basis of salt conservation at the ice-ocean interface. The bulk heat transfer model is then calibrated using the former model. The two models predict ocean heat fluxes that are quite variable in time owing to short-term variations in the ice drift. Both models calculate realistic ice thicknesses. It is demonstrated that the observed time variation in ice thickness from eight different experimental sites with varying initial thicknesses and bottom topographies can be reproduced by applying bulk heat transfer coefficients in the range (2.8 +/- 1) x 10(-4). Horizontal variation of the thermal state within a single pack ice floe results in simultaneous freezing and melting over relatively small spatial scales. When modeling or averaging ice data in space these aspects need to be considered.

  • 1365.
    Harlin, Joakim
    et al.
    SMHI.
    KUNG, CS
    PARAMETER UNCERTAINTY AND SIMULATION OF DESIGN FLOODS IN SWEDEN1992Ingår i: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 137, nr 1-4, s. 209-230Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper examines the effects of parameter uncertainty on the simulation of recorded floods and design floods, using the HBV hydrological model. Two Swedish catchments with hydropower development were studied. A Monte Carlo procedure was used to generate parameter sets of different levels of uncertainty. The results showed that the most sensitive parameters in the calibration process were the snowfall correction factor and the recession parameters. Furthermore, when the model was extrapolated to simulate design flood and water stage hydrographs, the single most sensitive parameter was the highest recession coefficient. In addition, it was found that parameter uncertainty was associated with combinations of parameters rather than the absolute values of each.

  • 1366.
    Sjöberg, Björn
    et al.
    SMHI, Samhälle och säkerhet.
    STIGEBRANDT, A
    COMPUTATIONS OF THE GEOGRAPHICAL-DISTRIBUTION OF THE ENERGY FLUX TO MIXING PROCESSES VIA INTERNAL TIDES AND THE ASSOCIATED VERTICAL CIRCULATION IN THE OCEAN1992Ingår i: DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, ISSN 0198-0149, Vol. 39, nr 2A, s. 269-&Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The global flux of tidal energy to mixing processes via topographically generated internal waves is estimated utilizing gridded databases for bathymetry, vertical density stratification and barotropic tides together with a simple, local model for the generation of progressive internal tides at vertical steps in the ocean floor. Both the horizontal distribution of the energy flux to internal tides and its ocean mean are discussed. The computed oceanic mean value is 44 x 10(-4) W m-2, a factor of about 2-3 greater than previous estimates (MUNK, 1966, Deep-Sea Research, 13, 707-730; BELL. 1975, Journal of Geophysical Research, 80, 320-327). The global distribution of vertical diffusivity in the abyss is computed by assuming that topographically generated baroclinic motions dissipate locally and that the dissipation is distributed vertically according to an empirical law. Our results are linearly dependent on the flux Richardson number R(f). From the computed vertical diffusivities and the known vertical stratification we finally compute the global distribution of vertical velocities. Choosing a value of R(f) almost-equal-to 0.05 we obtain an upward vertical transport in the interior of the ocean, at the 1000 m level, of about 15 x 10(6) m3 s-1, which agrees with WARREN's (1981, in: Evolution of physical oceanography, B. A. WARREN and C. WUNSCH, editors. 6-41) estimated rate of sinking from surface waters at high latitudes. Below the 1000 m level the upward vertical transport increases and a maximum value of about 25 x 10(6) m3 s-1 is found at the 2000 m level, after which the transport decreases to about 8 x 10(6) m3 s-1 at the 4000 m level. This may be explained by the action of bottom currents. These currents entrain ambient water whereby the upward interior vertical transports tend to increase with depth. However, because of the entrainment of lighter ambient fluid the dense currents become less dense and only the most dense flows penetrate to the greatest depths.

  • 1367. ASKNE, J
    et al.
    LEPPARANTA, M
    Thompson, Thomas
    SMHI.
    THE BOTHNIAN EXPERIMENT IN PREPARATION FOR ERS-1, 1988 (BEPERS-88) - AN OVERVIEW1992Ingår i: International Journal of Remote Sensing, ISSN 0143-1161, E-ISSN 1366-5901, Vol. 13, nr 13, s. 2377-2398Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BEPERS-88 was an extensive field campaign on the use of Synthetic Aperture Radar (SAR) in sea ice remote sensing in the Baltic Sea. This experiment was performed in order to study the possibilities of using the ERS-1 satellite SAR (and radar altimeter) in connection with the brackish ice in the Baltic Sea. The Canada Centre for Remote Sensing CV-580 C/X-band SAR was flown and an extensive validation programme was carried out. The data have been used for SAR image analysis, backscatter investigations, geophysical validation of SAR over sea ice, and evaluation of the potentials of SAR in operational ice information services. The results indicate that SAR can be used to discriminate between ice and open water, classify ice types into three categories, quantify ice ridging intensity, and determine the ice drift. As an operational tool SAR is expected to be an excellent complement to NOAA imagery and ground truth.

  • 1368.
    Bergström, Sten
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    Harlin, Joakim
    SMHI.
    Lindström, Göran
    SMHI, Forskningsavdelningen, Hydrologi.
    SPILLWAY DESIGN FLOODS IN SWEDEN .1. NEW GUIDELINES1992Ingår i: Hydrological Sciences Journal, ISSN 0262-6667, E-ISSN 2150-3435, Vol. 37, nr 5, s. 505-519Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The new Swedish guidelines for the estimation of design floods for dams and spillways are presented, with emphasis on high-hazard dams. The method is based on a set of regional design precipitation sequences, rescaled for basin area, season and elevation above sea level, and a full hydrological model. A reservoir operation strategy is also a fundamental component of the guidelines. The most critical combination of flood generating factors is searched by systematically inserting the design precipitation sequence into a ten year climatological record, where the initial snowpack has been replaced by a statistical 30-year snowpack. The new guidelines are applicable to single reservoir systems as well as more complex hydroelectric schemes, and cover snowmelt floods, rain floods and combinations of the two. In order to study the probabilities of the computed floods and to avoid regional inconsistencies, extensive comparisons with observed floods and frequency analyses have been carried out.

  • 1369.
    Lindström, Göran
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    Harlin, Joakim
    SMHI.
    SPILLWAY DESIGN FLOODS IN SWEDEN .2. APPLICATIONS AND SENSITIVITY ANALYSIS1992Ingår i: Hydrological Sciences Journal, ISSN 0262-6667, E-ISSN 2150-3435, Vol. 37, nr 5, s. 521-539Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recently developed guidelines for design flood calculation in Sweden are based on simulation with a hydrological model. Several meteorological and hydrological conditions are prescribed as input to the model. The sensitivity of the floods according to the new guidelines with respect to those prescriptions is checked as well as the sensitivity to the modelling procedure. In this paper, the HBV hydrological model is used. It is shown that the most sensitive input factor is the design 14-day precipitation sequence. For autumn floods, the scaling relation between the precipitation sequence and the generated floods is in the order of 1:1. For spring floods on the other hand, snowmelt influences the flood magnitude and reduces the sensitivity to precipitation to about 1:0.6. Soil moisture modelling was important in basins with high evapotranspiration. Model calibration could have a large effect on the design flood magnitude. The most sensitive parameter was the high flow recession coefficient, K0. The water stage development in a multi-reservoir system is further influenced by the regulation strategy and spillway capacity. An increased spillway capacity can improve the situation considerably for a particular dam but could at the same time worsen the situation for downstream dams. After the filling of the reservoir there was a clear relation between inflow peak and maximum water stage. The study shows that it is difficult to assess the integrated effects of extreme precipitation, snowmelt, soil moisture status and regulation in a system beforehand.

  • 1370.
    Lindström, Göran
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    RODHE, A
    TRANSIT TIMES OF WATER IN SOIL LYSIMETERS FROM MODELING OF O-181992Ingår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 65, nr 1-2, s. 83-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A proper description of water pathways and transit times is important in the simulation of groundwater acidification using hydrochemical models. A simple water balance model, describing water flow and transit times in different soil layers, was developed and tested by the use of the stable isotope O-18 as a natural tracer in soil lysimeters. Drainage was collected from lysimeters of three depths: 15, 40, and 80 cm, from two sites in the Stubbetorp research basin in south-eastern Sweden. The content of O-18 in the precipitation and in the drainage from the lysimeters was measured during 2 yr. O-18 was regarded as an ideal tracer, and its concentration in the drainage was modeled using the concentration in the precipitation as input. The percolation from each soil layer was assumed to depend on the inflow and the soil moisture storage in the layer. The most important model parameter, the field capacity, was derived from field information. Sensitivity analysis showed that the model was rather insensitive to other parameter values. Although simple, the model gave good results, both for the flow of water and O-18. The best results were obtained, when ideal mixing in the upper horizons of the soil was combined with piston flow at greater depths. Preferential flow was not found to be of great importance, nor was immobile water. Particle flow velocities and transit times in the soil lysimeters were simulated. The average particle flow velocities were about 0.6 cm d-1. The use of a dynamic model made it possible to simulate the temporal variations in transit times for water in the soil lysimeters. The mean transit times for the 80 cm lysimeter ranged from about 3 to 6 mo with an average value of 4 mo.

  • 1371.
    Harlin, Joakim
    SMHI.
    MODELING THE HYDROLOGICAL RESPONSE OF EXTREME FLOODS IN SWEDEN1992Ingår i: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 23, nr 4, s. 227-244Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hydrological models are today used for simulating extreme floods with the purpose of designing dams and spillways. In doing so, an extrapolation beyond the floods of the calibration period is made. This paper addresses this problem in connection to the HBV hydrological model. The model component describing flood dynamics, the runoff-response function, is studied. The methodology has been to calibrate different runoff-response functions over small to moderately large floods and to verify the performance over independent periods containing large experienced floods. Furthermore, the different model versions were run with extreme rainfall in order to generate design floods. It was found that the five-parameter response function of the original HBV model could be replaced by nonlinear functions including fewer parameters. However, it was difficult to select any response function formulation as significantly better than the others when extreme floods larger than those of the calibration period were simulated.

  • 1372.
    Langner, Joakim
    et al.
    SMHI, Forskningsavdelningen, Luftmiljö.
    RODHE, H
    CRUTZEN, PJ
    ZIMMERMANN, P
    ANTHROPOGENIC INFLUENCE ON THE DISTRIBUTION OF TROPOSPHERIC SULFATE AEROSOL1992Ingår i: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 359, nr 6397, s. 712-716Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    HUMAN activities have increased global emissions of sulphur gases by about a factor of three during the past century, leading to increased sulphate aerosol concentrations, mainly in the Northern Hemisphere. Sulphate aerosols can affect the climate directly, by increasing the backscattering of solar radiation in cloud-free air, and indirectly, by providing additional cloud condensation nuclei1-4. Here we use a global transport-chemistry model to estimate the changes in the distribution of tropospheric sulphate aerosol and deposition of non-seasalt sulphur that have occurred since pre-industrial times. The increase in sulphate aerosol concentration is small over the Southern Hemisphere oceans, but reaches a factor of 100 over northern Europe in winter. Our calculations indicate, however, that at most 6% of the anthropogenic sulphur emissions is available for the formation of new aerosol particles. This is because about one-half of the sulphur dioxide is deposited on the Earth's surface, and most of the remainder is oxidized in cloud droplets so that the sulphate becomes associated with pre-existing particles. Even so, the rate of formation of new sulphate particles may have doubled since pre-industrial times.

  • 1373.
    Josefsson, Weine
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    FOCUSED SUN OBSERVATIONS USING A BREWER OZONE SPECTROPHOTOMETER1992Ingår i: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 97, nr D14, s. 15813-15817Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accurate measurements of total ozone at high latitudes during winter have become increasingly important for studies of polar ozone depletion. The direct Sun measurements are the most direct and physically well defined type of measurement of total ozone with Dobson and Brewer spectrophotometers along with the focused Sun measurements. The direct Sun and focused Sun method are influenced by many sources of error at low solar elevations. A large error arises from the addition of radiation scattered from air along the path of the solar beam. A method to correct for this error using the Brewer instrument is described. The method gives reasonably accurate values down to solar elevations of 5-degrees compared to 10-degrees-20-degrees without corrections. This is especially important for high-latitude stations, where the low solar elevations are a limiting factor for accurate measurements of the total ozone particularly during the winter.

  • 1374.
    Andersson, Tage
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Lindgren, Bo
    SMHI.
    A SEA-BREEZE FRONT SEEN BY RADAR1992Ingår i: METEOROLOGICAL MAGAZINE, ISSN 0026-1149, Vol. 121, nr 1443, s. 239-241Artikel i tidskrift (Refereegranskat)
  • 1375.
    Fogelqvist, Elisabet
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Krysell, Mikael
    SMHI, Samhälle och säkerhet.
    NATURALLY AND ANTHROPOGENICALLY PRODUCED BROMOFORM IN THE KATTEGATT, A SEMIENCLOSED OCEANIC BASIN1991Ingår i: Journal of Atmospheric Chemistry, ISSN 0167-7764, E-ISSN 1573-0662, Vol. 13, nr 4, s. 315-324Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The origin of bromoform in seawater and atmosphere, as well as possible sinks and breakdown mechanisms, is discussed. A bromoform budget is calculated for the Kattegatt area between Sweden and Denmark, where the input of bromoform from a power plant is significant. Both anthropogenically (250 x 10(6) g yr-1) and biogenically (350 x 10(6) g yr-1, 0.016 g m-2 yr-1) produced bromoform is likely to have a great impact locally on the inventory and the release to the atmosphere. Using measured sur-face concentrations of bromoform, the total annual release from the Kattegatt to the atmosphere is estimated to 550 x 10(6) g (0.025 g m-2 yr-1).

  • 1376.
    Fogelqvist, Elisabet
    SMHI, Forskningsavdelningen, Oceanografi.
    DIMETHYLSULFIDE (DMS) IN THE WEDDELL SEA-SURFACE AND BOTTOM WATER1991Ingår i: Marine Chemistry, ISSN 0304-4203, E-ISSN 1872-7581, Vol. 35, nr 1-4, s. 169-177Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dimethylsulphide (DMS) has been measured in the water of the Weddell Sea during the austral summer 1988-1989. In the Summer Surface Water, which generally contained a maximum at 20-50 m depth, the concentrations were extremely high, up to 12 000 ng l-1 DMS, but showed a significant spatial variability. Data from the central part of the Weddell Sea show a steep gradient downwards, and below about 200 m depth, in the Weddell Sea Deep Water, concentrations were below the detection limit of 1 ng l-1. The high-density Ice Shelf Water, when flowing down the continental slope, brings DMS down to the Weddell Sea Bottom Water in significant amounts before its eventual decay.

  • 1377.
    Bergström, Sten
    SMHI, Forskningsavdelningen, Hydrologi.
    PRINCIPLES AND CONFIDENCE IN HYDROLOGICAL MODELING1991Ingår i: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 22, nr 2, s. 123-136Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    General principles in development and application of hydrological models are discussed and related to the confidence in the results. The presentation is mainly based on the experience from the work with the HBV and PULSE models at the Swedish Meteorological and Hydrological Institute between 1971 and 1990 but has also been influenced by other modelling work. It covers a discussion on the optimal complexity of models, use of observations, calibration, control and sensitivity analysis. Special attention is given to the uncertainties encountered when using hydrological models for the simulation of extreme floods and long-term scenario simulations. Finally a few ethical problems in modelling are mentioned.

  • 1378.
    Sandén, Per
    et al.
    SMHI, Forskningsavdelningen, Hydrologi.
    Rahm, Lars
    SMHI, Forskningsavdelningen, Oceanografi.
    WULFF, F
    NONPARAMETRIC TREND TEST OF BALTIC SEA DATA1991Ingår i: Environmetrics, ISSN 1180-4009, E-ISSN 1099-095X, Vol. 2, nr 3, s. 263-278Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The recently reported tendencies toward decreasing total amounts of silicate in the Baltic Sea are investigated by use of non-parametric trend analysis. The period 1968-1986 showed significant falling trends in surface waters from the whole system. The deepest parts of the Baltic proper did in contrast reveal strong increasing trends. These trends are more pronounced during the latter part of the analysis period which is characterized by stagnant conditions in the Baltic proper. These conditions have been prevailing since the major inflow in 1976. The causes of the observed changes are unclear. The increased load of nutrients and accompanying increase in primary production is, however, one factor. Another is coupled to the stagnation conditions of the Baltic Proper.

  • 1379.
    Sandén, Per
    SMHI, Forskningsavdelningen, Hydrologi.
    ESTIMATION AND SIMULATION OF METAL MASS-TRANSPORT IN AN OLD MINING AREA1991Ingår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 57-8, s. 387-397Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In a watershed with an old mine tailings deposit, mass transport of Cu, Zn and Cd was studied. An extensive sampling program and the use of the PULSE model for the simulation of water flow made it feasible to simulate and compare the dynamics of metal transport at different sites in the study area. Close to the tailings deposit, the weathering rate in the deposit had a large impact on the dynamics of the mass transport, and interannual variation in mass transport was considerably lower than the variation in runoff. Further downstream, the mass transport was almost exclusively determined by the water flow and, thus far unidentified, mechanisms maintained fairly constant metal concentrations in the stream water. The usefulness of the PULSE model for simulating metal concentrations may still be questioned. However, it is noteworthy that a hydrochemical model based on a fairly simple description of the mixing of water from different sources and a very simple pH dependence of the concentration of metals, at least semi-quantitatively, can reproduce the dynamics of metal concentrations and mass transport of metals.

  • 1380.
    Harlin, Joakim
    SMHI.
    DEVELOPMENT OF A PROCESS ORIENTED CALIBRATION SCHEME FOR THE HBV HYDROLOGICAL MODEL1991Ingår i: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 22, nr 1, s. 15-36Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A process oriented calibration scheme (POC), developed for the HBV hydrological model is presented. Twelve parameters were calibrated in two steps. Firstly, initial parameter estimates were made from recession analysis of observed runoff. Secondly, the parameters were calibrated individually in an iteration loop starting with the snow routine, over the soil routine and finally the runoff-response function. This was done by minimizing different objective functions for different parameters and only over subperiods where the parameters were active. Approximately three hundred and fifty objective function evaluations were needed to find the optimal parameter set, which resulted in a computer time of about 17 hours on a 386 processor PC for a ten-year calibration period. Experiments were also performed with fine tuning as well as direct search of the response surface, where the parameters were allowed to change simultaneously. A calibration period length of between two and six years was found sufficient to find optimal parameters in the test basins. The POC scheme yielded as good model performance as after a manual calibration.

  • 1381. HOFGAARD, A
    et al.
    KULLMAN, L
    Alexandersson, Hans
    SMHI.
    RESPONSE OF OLD-GROWTH MONTANE PICEA-ABIES (L) KARST FOREST TO CLIMATIC VARIABILITY IN NORTHERN SWEDEN1991Ingår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 119, nr 4, s. 585-594Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Repeat photography and tree ring analyses were used to investigate structural change, 1938-88, of an old growth and high elevation Picea abies (L.) Karst. forest in northern Sweden. The forest, initially moribund, senescent and top-broken, regenerated broken tops and apparently gained in vigour. Up to the 1930s this progressive change was pre-dated by an increase of annual increment growth, which subsequently declined until the 1980s. The tree-ring response concurs with the general course of summer temperature while canopy processes appear to lag behind. The study stresses the importance of phenotypic plasticity for long-term behaviour of marginal spruce forest. It is also evident that canopy development is not a fully predictable ageing process, but to some extent dependent on climatic variability.

  • 1382.
    Taesler, Roger
    SMHI, Forskningsavdelningen.
    THE BIOCLIMATE IN TEMPERATE AND NORTHERN CITIES1991Ingår i: International journal of biometeorology, ISSN 0020-7128, E-ISSN 1432-1254, Vol. 35, nr 3, s. 161-168Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Climate is a basic component of the human environment. Developments in building design and indoor climate control have contributed greatly to improving human health and comfort. By contrast, the possibilities for improving urban climatic conditions by deliberate planning have been poorly exploited. The structure and processes of the urban atmosphere in extratropical regions are briefly described. The impact of certain selected urban climates on human health is summarized. The need for relevant bioclimatological "design tools" for applications in urban planning is stressed, followed by a brief review of some recent work on human thermal comfort. It is argued that the modification of present day comfort criteria to reflect human adaptation to climate may be important for further improvements of indoor climate. as well as for deducing the emissions of air pollutants and greenhouse gases.

  • 1383.
    Andersson, Tage
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Ivarsson, Karl-Ivar
    SMHI.
    A MODEL FOR PROBABILITY NOWCASTS OF ACCUMULATED PRECIPITATION USING RADAR1991Ingår i: Journal of applied meteorology (1988), ISSN 0894-8763, E-ISSN 1520-0450, Vol. 30, nr 1, s. 135-141Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new model for making probability forecasts of accumulated spot precipitation from weather radar data is presented. The model selects a source region upwind of the forecast spot. All pixels (horizontal size 2 x 2 km2) within the source region are considered, having the same probability of hitting the forecast spot. A pixel hitting the forecast spot is supposed to precipitate there a short time (about 10 min.). A drawing is performed, and a frequency distribution of accumulated precipitation during the first time step of the forecast is obtained. A second drawing gives the frequency distribution of accumulated precipitation during the first to second time step, a third one during the first to third, and so on until the end of the forecast period is reached. A number of forecasts for 1-h accumulated precipitation, with lead times of 0, 1, and 2 h, have been performed and verified. The forecasts for 0-h lead time got the highest Brier skill scores, +50% to 60% relative to climatological forecasts for accumulated precipitation below 1 mm.

  • 1384.
    Taesler, Roger
    SMHI, Forskningsavdelningen.
    CLIMATE AND BUILDING ENERGY MANAGEMENT1991Ingår i: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 16, nr 1-2, s. 599-608Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Indoor climate control is a major energy demand everywhere. Design and operation of buildings and HVAC systems crucially depend on climate data and real-time meteorological conditions. Energy-efficient buildings also contribute to reduce air pollution and climate change in urban areas as well as regionally and globally. However, the effects of climate and weather on building energy management are still largely overlooked in practice. A main reason for this is the lack of tools for translating meteorological conditions into energy requirements. The combined impact of temperature, solar irradiation, wind and humidity on the energy balance of a building depends on the building itself, i.e., its design, orientation, HVAC system, mode of operation, maintenance, etc. The paper discusses different approaches to model this complex interplay and associated problems at the design as well as in the operation stages. Recent developments in Sweden are reported, including applications to urban planning, building design and real-time operation of buildings and energy systems. The impact of solar irradiation and wind, in addition to that of temperature, is demonstrated. Further, the paper discusses the significance of local site condition versus building characteristics.

  • 1385.
    Andersson, Tage
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    A HEAVY MESOSCALE SNOWFALL EVENT IN NORTHERN GERMANY1991Ingår i: METEOROLOGICAL MAGAZINE, ISSN 0026-1149, Vol. 120, nr 1425, s. 67-68Artikel i tidskrift (Refereegranskat)
  • 1386.
    Svensson, Urban
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Omstedt, Anders
    SMHI, Forskningsavdelningen, Oceanografi.
    A MATHEMATICAL-MODEL OF THE OCEAN BOUNDARY-LAYER UNDER DRIFTING MELTING ICE1990Ingår i: Journal of Physical Oceanography, ISSN 0022-3670, E-ISSN 1520-0485, Vol. 20, nr 2, s. 161-171Artikel i tidskrift (Refereegranskat)
  • 1387.
    Brandt, Maja
    SMHI, Samhälle och säkerhet.
    SIMULATION OF RUNOFF AND NITRATE TRANSPORT FROM MIXED BASINS IN SWEDEN1990Ingår i: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 21, nr 1, s. 13-34Artikel i tidskrift (Refereegranskat)
  • 1388.
    Andersson, Lars
    et al.
    SMHI, Samhälle och säkerhet.
    Rahm, Lars
    SMHI, Forskningsavdelningen, Oceanografi.
    THERMALLY DRIVEN CIRCULATION WITHIN AN EXPERIMENTAL ENCLOSURE1990Ingår i: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 30, nr 2, s. 111-129Artikel i tidskrift (Refereegranskat)
  • 1389. WULFF, F
    et al.
    STIGEBRANDT, A
    Rahm, Lars
    SMHI, Forskningsavdelningen, Oceanografi.
    NUTRIENT DYNAMICS OF THE BALTIC SEA1990Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 19, nr 3, s. 126-133Artikel i tidskrift (Refereegranskat)
  • 1390. Rosenberg, R
    et al.
    Elmgren, R
    Fleischer, S
    Jonsson, P
    Persson, G
    Dahlin, Hans
    SMHI.
    MARINE EUTROPHICATION CASE-STUDIES IN SWEDEN1990Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 19, nr 3, s. 102-108Artikel i tidskrift (Refereegranskat)
  • 1391.
    Brandt, Maja
    SMHI, Samhälle och säkerhet.
    GENERATION, TRANSPORT AND DEPOSITION OF SUSPENDED AND DISSOLVED MATERIAL - EXAMPLES FROM SWEDISH RIVERS1990Ingår i: Geografiska Annaler. Series A, Physical Geography, ISSN 0435-3676, E-ISSN 1468-0459, Vol. 72, nr 3-4, s. 273-283Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Soil erosion, sediment transport and deposition in river systems in Sweden are discussed. The database consists of observations from a research project and from the Swedish network for the measurement of sediment transport. Examples are given from measurements in small plots, and from river basins of different sizes and characteristics. Effects of hydrological regime, of deposition in lakes, and of geology and human impact are illustrated. It was found that observations of erosion losses in index plots cannot easily be extrapolated to large areas, and that trends of transport most likely reflect trends in runoff.

  • 1392.
    Andersson, Tage
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Nilsson, Stefan
    SMHI, Samhälle och säkerhet.
    TOPOGRAPHICALLY INDUCED CONVECTIVE SNOWBANDS OVER THE BALTIC SEA AND THEIR PRECIPITATION DISTRIBUTION1990Ingår i: Weather and forecasting, ISSN 0882-8156, E-ISSN 1520-0434, Vol. 5, nr 2, s. 299-312Artikel i tidskrift (Refereegranskat)
  • 1393.
    Vedin, Haldo
    SMHI.
    FREQUENCY OF RARE WEATHER EVENTS DURING PERIODS OF EXTREME CLIMATE1990Ingår i: Geografiska Annaler. Series A, Physical Geography, ISSN 0435-3676, E-ISSN 1468-0459, Vol. 72, nr 2, s. 151-155Artikel i tidskrift (Refereegranskat)
  • 1394.
    Eriksson, Bertil
    et al.
    SMHI.
    Alexandersson, Hans
    SMHI, Forskningsavdelningen.
    OUR CHANGING CLIMATE1990Ingår i: Agricultural and Forest Meteorology, ISSN 0168-1923, E-ISSN 1873-2240, Vol. 50, nr 1-2, s. 55-64Artikel i tidskrift (Refereegranskat)
  • 1395.
    Rahm, Lars
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Svensson, Urban
    SMHI, Forskningsavdelningen, Oceanografi.
    Dispersion in a stratified benthic boundary layer1989Ingår i: Tellus. Series A, Dynamic meteorology and oceanography, ISSN 0280-6495, E-ISSN 1600-0870, Vol. 41A, nr 2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A dispersion model for the stratified benthic boundary layer is formulated. It is based on "small-scale" vertical dispersion and a "large-scale" horizontal flow field. A modified Langevin equation governs the stochastic vertical migration of an ensemble of marked fluid elements. These elements are spread out by the horizontal flow, determined by a one-dimensional model, which includes a two-equation (k - epsilon) turbulence scheme. The later yields statistical information necessary for the stochastic process. Statistical properties of the dispersion process are then calculated from the evolution of the ensemble of elements. A rather idealized case with a linearly stratified fluid subject to a suddenly imposed barotropic pressure gradient is considered. A quasi-geostrophic interior flow is formed with a benthic boundary layer at the bottom. Marked fluid elements are released at the bottom and then followed for several pendulum days. It is found that the dispersion process is well characterized by K = Cu(*)l/(where u(*) and l are the friction velocity at the bottom and the layer thickness, respectively), and where C approximate to 15. A similar relation but based on external parameters only, becomes: K = C-b vertical bar partial derivative P/partial derivative y vertical bar(2)/rho(2) f(5/2) N-1/2, where C-b approximate to 0.11 in the range N/f = 28- 88

  • 1396.
    Rahm, Lars
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Svensson, Urban
    SMHI, Forskningsavdelningen, Oceanografi.
    ON THE MASS-TRANSFER PROPERTIES OF THE BENTHIC BOUNDARY-LAYER WITH AN APPLICATION TO OXYGEN FLUXES1989Ingår i: NETHERLANDS JOURNAL OF SEA RESEARCH, ISSN 0077-7579, Vol. 24, nr 1, s. 27-35Artikel i tidskrift (Refereegranskat)
  • 1397.
    Svensson, Urban
    et al.
    SMHI, Forskningsavdelningen, Oceanografi.
    Sahlberg, Jörgen
    SMHI, Affärsverksamhet.
    FORMULAS FOR PRESSURE-GRADIENTS IN ONE-DIMENSIONAL LAKE MODELS1989Ingår i: JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, Vol. 94, nr C4, s. 4939-4946Artikel i tidskrift (Refereegranskat)
  • 1398.
    Karlsson, Karl-Göran
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    DEVELOPMENT OF AN OPERATIONAL CLOUD CLASSIFICATION MODEL1989Ingår i: International Journal of Remote Sensing, ISSN 0143-1161, E-ISSN 1366-5901, Vol. 10, nr 4-5, s. 687-693Artikel i tidskrift (Refereegranskat)
  • 1399.
    Häggkvist, Kenneth
    et al.
    SMHI, Affärsverksamhet.
    Svensson, Urban
    SMHI, Forskningsavdelningen, Oceanografi.
    Taesler, Roger
    SMHI, Forskningsavdelningen.
    NUMERICAL SIMULATIONS OF PRESSURE FIELDS AROUND BUILDINGS1989Ingår i: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 24, nr 1, s. 65-72Artikel i tidskrift (Refereegranskat)
  • 1400.
    Andersson, Tage
    et al.
    SMHI, Forskningsavdelningen, Atmosfärisk fjärranalys.
    Andersson, M
    SMHI.
    Jacobsson, Caje
    SMHI.
    Nilsson, Stefan
    SMHI.
    THERMODYNAMIC INDEXES FOR FORECASTING THUNDERSTORMS IN SOUTHERN SWEDEN1989Ingår i: METEOROLOGICAL MAGAZINE, ISSN 0026-1149, Vol. 118, nr 1404, s. 141-146Artikel i tidskrift (Refereegranskat)
2526272829 1351 - 1400 av 1419
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