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  • 401.
    Viktorsson, Lena
    et al.
    SMHI, Core Services.
    Wesslander, Karin
    SMHI, Core Services.
    Revidering av fysikaliska och kemiskabedömningsgrunder i kustvatten: Underlag inför uppdatering av HVMFS 2013:192018Report (Other academic)
    Abstract [sv]

    Detta är ett underlag för revidering av bilaga 5 i HVMFS 2013:19, Bedömningsgrunder för fysikaliskkemiskakvalitetsfaktorer i kustvatten och vatten i övergångszonen. Underlaget innefattar främst enuppdatering av referensvärden för näringsämnen samt förslag på uppdatering av viss text i föreskriftengällande syrebalans och siktdjup. Den generella metoden för var och en av stödparametrarna ibedömningsgrunderna bibehålls. I rapportens sista kapitel presenteras de uppdateringar av föreskriftenHVMFS 2013:19 som rekommenderas utifrån detta uppdrag.Efter en jämförelse av tidigare framtagna referensvärden för näringsämnen och de som tagits fram iden här rapporten rekommenderas att nya referensvärden i tillrinnande sötvatten används men atttidigare referensvärden för TN och TP vid utsjösalthalt samt att klassgränser behålls. En mindrejustering av referensvärden för DIN och DIP utifrån havsmiljöförordningens G/M värden föreslåsdock. De nya referensvärdena är framtagna med modellen S-HYPE (Lindström m.fl. 2010) förtillrinnande sötvatten och utifrån utsjövärden för oorganiskt fosfor och kväve (HVMFS 2012:18) samteffektsamband i mätdata. Det förtydligas också att ett konstant referensvärde för näringsämnenanvänds vid salthalter ≤2 psu.Den S-HYPE körning som använts för referensvärden i tillrinnande sötvatten är en bakgrundskörningsom är anpassad till definitionen av bakgrundsbelastning i PLC6 (Pollution Load Compilation 6,HELCOM).Utöver uppdatering av referensvärden för näringsämnen så föreslås en förändrad sammanvägning avkväve och fosfor i bedömningsgrunden. Det innebär att de ingående parametrarna för kväve och fosforsammanvägs var för sig. Bedömningsgrunderna ger då en separat status för varje näringsämne (kväveoch fosfor) baserat på de ingående parametrarna. Detta ger både en större möjlighet till att se vilketnäringsämne som bidrar till att eventuellt sänka status och stämmer överens med hur rapporteringentill EU-kommissionen ska ske.För syre rekommenderas en uppdatering om vilka mätmetoder som får användas, så att ävenmätningar med sensorer kan användas för statusbedömning. För siktdjup var ambitionen att ta fram etthumusgränsvärde för när kvalitetsfaktorn inte ska tillämpas. En fullständig statistisk analys har intehunnits med och en tydlig rekommendation kan inte ges.Det har under arbetet med att ta fram nya referensvärden för näringsämnen enligt nuvarande metodblivit tydligt att metoden för att bedöma näringsämnen behöver en mer övergripande uppdatering. Tillexempel kan metoden för salthaltskorrektion troligen förbättras med hjälp av en analys av mätdata ikombination med kustzonsmodellen.

  • 402. von Schuckmann, Karina
    et al.
    Le Traon, Pierre-Yves
    Alvarez-Fanjul, Enrique
    Axell, Lars
    SMHI, Research Department, Oceanography.
    Balmaseda, Magdalena
    Breivik, Lars-Anders
    Brewin, Robert J. W.
    Bricaud, Clement
    Drevillon, Marie
    Drillet, Yann
    Dubois, Clotilde
    Embury, Owen
    Etienne, Hélène
    Sotillo, Marcos García
    Garric, Gilles
    Gasparin, Florent
    Gutknecht, Elodie
    Guinehut, Stéphanie
    Hernandez, Fabrice
    Juza,, Melanie
    Karlson, Bengt
    SMHI, Research Department, Oceanography.
    Korres, Gerasimos
    Legeais, Jean-François
    Levier, Bruno
    Lien, Vidar S.
    Morrow, Rosemary
    Notarstefano, Giulio
    Parent, Laurent
    Pascual, Álvaro
    PérezGómez, Begoña
    Perruche, Coralie
    Pinardi, Nadia
    Pisano, Andrea
    Poulain, Pierre-Marie
    Pujol, Isabelle M.
    Raj, Roshin P.
    Raudsepp, Urmas
    Roquet, Hervé
    Samuelsen, Annette
    Sathyendranath, Shubha
    She, Jun
    Simoncelli, Simona
    Cosimo, Solidoro
    Tinker, Jonathan
    Tintoré, Joaquín
    Viktorsson, Lena
    SMHI, Core Services.
    Ablain, Michael
    Almroth-Rosell, Elin
    SMHI, Research Department, Oceanography.
    Bonaduce, Antonio
    Clementi, Emanuela
    Cossarini, Gianpiero
    Dagneaux, Quentin
    Desportes, Charles
    Dye, Stephen
    Fratianni, Claudia
    Good, Simon
    Greiner, Eric
    Gourrion, Jerome
    Hamon, Mathieu
    Holt, Jason
    Hyder, Pat
    Kennedy, John
    ManzanoMuñoz, Fernando
    Melet, Angélique
    Meyssignac, Benoit
    Mulet, Sandrine
    Buongiorno Nardelli, Bruno
    O´Dea, Enda
    Olason, Einar
    Paulmier, Aurélien
    Pérez-González, Irene
    Reid, Rebecca
    Racault, Marie-Fanny
    Raitsos, Dionysios E.
    Ramos,, Antonio
    Sykes, Peter
    Szekely, Tanguy
    Verbrugge, Nathalie
    The Copernicus Marine Environment Monitoring Service Ocean State Report2017In: Journal of operational oceanography. Publisher: The Institute of Marine Engineering, Science & Technology, ISSN 1755-876X, E-ISSN 1755-8778, Vol. 9, no Sup.2, p. 235-320Article in journal (Refereed)
  • 403. Walve, J
    et al.
    Höglander, H
    Andersson, A
    Karlson, Bengt
    SMHI, Research Department, Oceanography.
    Karlsson, C
    Johansen, Marie
    SMHI, Core Services.
    Phytoplankton in coastal waters2016In: Ecological Assessment of Swedish Water Bodies; development, harmonisation and integration of biological indicators.: Final report of the research programme WATERS. Deliverable 1.1-4, WATERS report no 2016:10. Havsmiljöinstitutet, Sweden, 95-106., 2016Chapter in book (Other academic)
  • 404.
    Wern, Lennart
    SMHI, Core Services.
    Avesta stadsmodell1985Report (Other academic)
  • 405.
    Wern, Lennart
    SMHI, Core Services.
    Extrem nederbörd i Sverige under 1 till 30 dygn, 1900 - 20112012Report (Other academic)
    Abstract [en]

    This study shows that, in general, extreme precipitation has increased from 1900 until the 1930s and then reduced until the 1970s, before increasing until the present day. There is more extreme precipitation now than in the 1930s. In particular an accumulation of extreme precipitation in Götaland (the southern part of Sweden) has been seen during the 2000s. It has been noted that the greatest precipitation in Sweden usually occurs in July or August but there are some exceptions for different parts of the country and different seasons. We need to be careful about extrapolating the last 40 years increase into the future in the belief that the increase will continue. This report says nothing about the future, and those interested in extreme precipitation in a future climate should study the results of climate models that calculate future scenarios. Areas affected by the worst downpours during one day are mainly the southern coast of Norrland, Svealand, eastern Götaland and Skåne. Western Götaland, in particular central Halland, is often affected by large precipitation volumes but does not usually receive the highest amounts. The mountains have also had extreme rainfall but usually during a longer period of time – from a week up to 30 days. This report describes extreme precipitation lasting from 1 to 30 days during 112 years, between 1900 and 2011. Only digital data has been used to compile the information in this report. A large proportion of precipitation data before 1961 is unfortunately only available in paper format and could not be used in this study. Prior to 1961, there were only about 60 digital stations, but since 1961 there have been about 700 operational stations. A digitalisation project is being carried out at SMHI to transfer data from paper logs to digital form so that it can be processed by computer programs. This is a large project that will take many years to complete. Sixty stations with a time series of at least 100 years between 1900 and 2011 have been selected to describe how extreme precipitation has varied over 112 years. These stations are fairly evenly distributed throughout the country. Calculating recurrence times required stations with at least 25 years of data during the period 1961 – 2011, which means that over 670 stations have been used. All precipitation measurements are associated with errors due to for example aerodynamic problems and evaporation, which often leads to an underestimation of the precipitation volume. This study has focused on extreme precipitation which often falls in the form of large rain drops. The underestimation is assumed to be less than an average of 5 – 10 %. There has been a gradual improvement in the quality of the precipitation measurements due to the introduction of wind shields around the rain gauges up until 1935 and a switch from zinc containers to seamless aluminium containers (without the risk of leakage) up until the start of the 1960s. After that, precipitation has been measured in the same way until 1996 when around 100 of the 750 stations were changed to a new type of automatic gauge with a different type of wind shield. This report makes no attempt at homogenising the data, and uses the observed values directly. There is however a discussion on different error sources. Variations in extreme precipitation during the 112-year period of study have been described in this report for Sweden as a whole but also for different seasons and for different parts of the country: Northern Norrland, southern Norrland, Svealand and Götaland. The most extreme cases have been analysed using maps with a short descriptive text. Recurrence times of precipitation volumes with different durations are calculated and presented on a map.

  • 406.
    Wern, Lennart
    SMHI, Core Services.
    Extrema byvindar i Orrefors1986Report (Other academic)
  • 407.
    Wern, Lennart
    SMHI, Core Services.
    Luftfuktighet: Variationer i Sverige2014Report (Other academic)
    Abstract [en]

    This report gives a general description of water vapour which is a transparent and odourless gas, how this gas varies geographically outdoors in Sweden as well as the diurnal and annual variation. Humidity data from 121 automatic weather stations that were operational during the period 1996-2012 was used. The measurements were taken at 1.5 to 2 meters above the ground level. Different measuring instruments for humidity are presented and also different humidity measurements like dew point, wet bulb, absolute humidity, mixing ratio, enthalpy etc. The absolute humidity which is the mass of water vapour in a cubic meter of air is highest in summer and lowest during the coldest days in winter. The highest values are measured along the coasts of southern Sweden and the value decreases northwards and with distance from the coast. Diurnal variation of the absolute humidity is in average relatively small. In addition, monthly mean water vapour is studied for various months since 1951. Digitized humidity data have not been available before in 1951. Ten stations are used, from Bredåkra in the south of Sweden to Arjeplog in the north, for calculating monthly averages. The months May, August and November have been chosen together with the annual value. The absolute humidity increased during the three months and also the annual value. For the annual value and for May and August the increase is statistically significant not for November. There is no statistically significant change of the average relative humidity during the period 1951-2012 for the average of ten selected stations for the months of May, August or November. If the temperature drops to the dew point the air becomes saturated with water vapour and the relative humidity becomes 100 %. If the temperature drops further the water vapour condensates to water droplets and fog, dew or frost is formed. The highest dew point reported in Sweden is 23.8 °C at Fårö north of the island Gotland on 29 July 1994 and in Hällum in Västergötland on 30 June 1997. At the latter occasion the temperature was 28.4 °C and the relative humidity 76%. The relative humidity is usually given in percentage (%) that is a measure of how much water vapour the air contains compared to how much water vapour that the air can contain as a maximum at the ambient temperature. The amount of water vapour that can occur as gas form increases with temperature. Low relative humidity is common during spring and early summer, while high relative humidity occurs during nights and during winter. In May, when the sea water is cool, the relative humidity is higher along the Swedish coast compared to inland. In November, when the sea water is warmer than the land, there is a reverse relationship; the relative humidity is lower on the coast compared to inland. In Helsingborg, the relative humidity is in average 50-60% when the temperature is +25 °C, but when the temperature is between 0 and +10 °C the humidity is much higher, 90 to 100 %.

  • 408.
    Wern, Lennart
    SMHI, Core Services.
    Snödjup i Sverige 1904/05 – 2013/142015Report (Other academic)
    Abstract [sv]

    Rapporten ger en beskrivning av snöförhållandena i Sverige under vintrarna 1904/05 till 2013/14. Speciellt har vinterns största snödjup, antal dagar med snötäcke och stora snödjupsökningar under ett dygn studerats. Snödjupsrekord för olika månader och landsdelar har sammanställts. Svåra snövintrar beskrivs liksom olika exempel på extrema snöfall och snödjup med återkomsttiden 10 och 50 år. Vid en jämförelse av vintrarna under perioderna 1991 – 2014 med 1961 – 1990 så har vinterns största snödjup och antal dagar med snötäcke minskat i nästan hela landet. Stora snödjupsökningar från en dag till nästa beror ofta på så kallade snökanoner som oftast bildas över Östersjön vid vind från öster. Speciellt utsatt för snökanoner är Norrlandskusten från Skellefteå ner till Gävle men även Smålandskusten, Vänern och Vättern är drabbat. Den vinter som varit snörikast är 1965/66 om man ser till vinterns största snödjup i Sverige som helhet. I olika delar av Sverige har det under andra vintrar förekommit större snödjup än under 1965/66. Exempelvis var det extremt mycket snö i fjällen 1988/89 och vintern 2009/10 var den snörikaste vintern i Götaland under hela den studerade perioden.

  • 409.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för ASEA transformers i Ludvika1985Report (Other academic)
  • 410.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för ett kraftvärmeverk i Sundbyberg1986Report (Other academic)
  • 411.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för lösningsmedel i Tibro1986Report (Other academic)
  • 412.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för svavelsyrafabrik i Falun1986Report (Other academic)
  • 413.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för Volvo BM ABs anläggning i Braås1986Report (Other academic)
  • 414.
    Wern, Lennart
    SMHI, Core Services.
    Spridningsberäkningar för Volvo Hallsbergverken1986Report (Other academic)
  • 415.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Bärring, Lars
    SMHI, Research Department, Climate research - Rossby Centre.
    Sveriges vindklimat 1901-2008: Analys av trend i geostrofisk vind2009Report (Other academic)
    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 %.

  • 416.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Fredriksson, Ulf
    SMHI, Core Services.
    Spridningsberäkning för Kockums Plåt-teknik, Ronneby1986Report (Other academic)
  • 417.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Fredriksson, Ulf
    SMHI, Core Services.
    Ring, Sture
    SMHI, Professional Services.
    Spridningsberäkningar för lösningsmedel i Tidaholm1986Report (Other academic)
  • 418.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    German, Jonas
    SMHI.
    Korttidsnederbörd i Sverige 1995 - 20082009Report (Other academic)
    Abstract [sv]

    Korta men intensiva regnhändelser är mycket viktiga inom bland annat urban hydrologi då vi här har att göra med snabba förlopp där avrinningen sker från små ytor som till stor del är hårdgjorda. Nederbördsserier med hög upplösning har därför mycket stor betydelse för all planering, analys och dimensionering av dagvattensystem, oavsett om det är frågan om rörnät eller öppna diken. Regn med varaktighet 15 min till 96 timmar har studerats genom att analysera nederbördsdata från SMHIs nät av automatiska väderstationer.Dessa stationer började installeras under våren 1995 och från början av 1996 var de flesta stationer igång. Den period vi har studerat är maj 1995 till september 2008. 114 automatstationerna har registrerat nederbörd under någon del av denna period. Sammanlagt finns 1211 stationsår med 15 minuters nederbörd. Data har granskats och ett mindre antal orimliga observationer har tagits bort eller rättats. Sammanställningar av årets största regn med olika varaktigheter har gjorts. Nederbördsmängder med olika varaktighet från 15 min till 96 timmar för olika återkomsttider har beräknats med extremvärdesanalys.Den studerade perioden är för kort och antalet stationer är för få för att bestämma regionala skillnader i Sverige av korttidsnederbörd. Därför har medelvärden av korttidsnederbörd för hela Sverige beräknats. Resultat har jämförts med tidigare studier av Dahlström (2006) och Hernebring (2006). Överensstämmelsen är god för kortare regn och kortare återkomsttider.

  • 419.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Kindell, Sven
    SMHI, Professional Services.
    Robertson, Lennart
    SMHI, Research Department, Air quality.
    Luktberäkningar för AB ELMO i Flen1986Report (Other academic)
  • 420.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Omstedt, Gunnar
    SMHI, Research Department, Air quality.
    Spridningsberäkningar för Volvos planerade bilfabrik i Uddevalla - energicentralen1985Report (Other academic)
  • 421.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Ring, Sture
    SMHI, Professional Services.
    Spridningsberäkningar för ny ugn, SSAB II1986Report (Other academic)
  • 422.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Ring, Sture
    SMHI, Professional Services.
    Spridningsberäkningar för Västhamns-verket HKV1 i Helsingborg1986Report (Other academic)
  • 423.
    Wern, Lennart
    et al.
    SMHI, Core Services.
    Ring, Sture
    SMHI, Professional Services.
    Spridningsberäkningar, SSAB1986Report (Other academic)
  • 424.
    Wesslander, Karin
    SMHI, Core Services.
    Coastal eutrophication status assessment using HEAT 1.0 (WFD methodology) versus HEAT 3.0 (MSFD methodology) and  Development of an oxygen consumption  indicator2017Report (Other academic)
    Abstract [en]

    This report contains two parts which are self standing reports and a contribution to the HELCOM project EUTRO-OPER. The work has been funded and commissioned by SwAM (Swedish agency for marine and water management) 2014-2015.

    • Coastal eutrophication status assessment using HEAT 1.0 (WFD methodology) versus HEAT 3.0 (MSFD methodology)

    Eutrophication status is assessed nationally in coastal waters within the Water Framework Directive (WFD) and in open sea areas within the Marine Strategy Framework Directive (MSFD). Both WFD and MSFD consider eutrophication but with different approaches and it is therefore a need for harmonisation in the assessment process.   The Excel based tool HEAT (HELCOM Eutrophication Assessment Tool) has been used in previous assessments in the HELCOM region. There are two versions of the tool; HEAT 1.0 and HEAT 3.0, the first is based on the WFD methodology and the second is based on the MSFD methodology. The main difference between HEAT 1.0 and HEAT 3.0 is how the indicators are grouped. Here we assess the eutrophication status in coastal waters by applying HEAT and compare the results with the national WFD assessments. The present test includes data on 33 selected coastal water bodies in five countries: Estonia, Finland, Latvia, Poland and Sweden. Data on reference condition, acceptable deviation, status and class boundaries of all indicators used in WFD for reporting ecological status (biological and physical-chemical) have been provided for each tested water body. The data has been inserted in the HEAT 1.0 and HEAT 3.0 tools and been compared with the national WFD assessments.   Both HEAT versions gave lower status in more than 50 % of the cases. For some tests the status changed to sub-GES from GES when HEAT is applied. The good/moderate boundary is the same in both HEAT and the WFD while the lower class boundaries in general are stricter in HEAT, which explains the lower status. In national WFD assessments expert judgment is used when there is little, no or very uncertain in situ data. The status in HEAT is given by the one-out-all-out principle but it is still possible to include expert judgment through the weighting factors.

    • Development of an oxygen consumption indicator

    It was investigated if the oxygen consumption can be used as an oxygen indicator for the Baltic Sea. The method is based on the idea of calculating the oxygen consumption in a stabile layer below the productive zone during summer and relating this to nutrient concentrations. With more nutrients available there is an increased biological production. By estimating how much oxygen is needed to mineralise the biological material it may be possible to link the oxygen consumption to eutrophication.

    The oxygen consumption was calculated for the BY15-Gotland Deep in the Eastern Gotland Basin. We identified a stabile layer between 30 and 50 m and a large change in both oxygen and nutrients from June to August. However, the oxygen consumption had a very high inter-annual variation and there were no significant correlation with the winter mean of nutrient concentrations. It was not possible to calculate the diffusion between the layers because of too sparse measurements at the stratification which limits the method. The calculation of the diffusion is however possible to improve with a model. Further on, the depth of the stabile layer is varying between areas and also between years.   We realised that the method has too many restrictions to be a functional indicator. A functional indicator shall not be dependent on heavy modelling or demand too much on expert judgement. We also investigated if a possible candidate to use as a more simple oxygen consumption indicator could be the use of oxygen saturation at a specific depth. If we assume that the temperature has not changed much since the establishment of stratification we may expect that changes in oxygen saturation observed in August at this depth would be caused by the biological oxygen consumption occurring during late spring and summer. The correlation with winter mean nutrients slightly improved in this case.

  • 425.
    Wesslander, Karin
    SMHI, Core Services.
    Coastal eutrophication status assessment using HEAT 1.0 (WFD methodology) versus HEAT 3.0 (MSFD methodology) and Development of an oxygen consumption indicator2017Report (Other academic)
    Abstract [en]

    This report contains two parts which are self standing reports and a contribution to the HELCOM project EUTRO-OPER. The work has been funded and commissioned by SwAM (Swedish agency for marine and water management) 2014-2015.

    • Coastal eutrophication status assessment using HEAT 1.0 (WFD methodology) versus HEAT 3.0 (MSFD methodology)

    Eutrophication status is assessed nationally in coastal waters within the Water Framework Directive (WFD) and in open sea areas within the Marine Strategy Framework Directive (MSFD). Both WFD and MSFD consider eutrophication but with different approaches and it is therefore a need for harmonisation in the assessment process.  The Excel based tool HEAT (HELCOM Eutrophication Assessment Tool) has been used in previous assessments in the HELCOM region. There are two versions of the tool; HEAT 1.0 and HEAT 3.0, the first is based on the WFD methodology and the second is based on the MSFD methodology. The main difference between HEAT 1.0 and HEAT 3.0 is how the indicators are grouped. Here we assess the eutrophication status in coastal waters by applying HEAT and compare the results with the national WFD assessments. The present test includes data on 33 selected coastal water bodies in five countries: Estonia, Finland, Latvia, Poland and Sweden. Data on reference condition, acceptable deviation, status and class boundaries of all indicators used in WFD for reporting ecological status (biological and physical-chemical) have been provided for each tested water body. The data has been inserted in the HEAT 1.0 and HEAT 3.0 tools and been compared with the national WFD assessments.  Both HEAT versions gave lower status in more than 50 % of the cases. For some tests the status changed to sub-GES from GES when HEAT is applied. The good/moderate boundary is the same in both HEAT and the WFD while the lower class boundaries in general are stricter in HEAT, which explains the lower status. In national WFD assessments expert judgment is used when there is little, no or very uncertain in situ data. The status in HEAT is given by the one-out-all-out principle but it is still possible to include expert judgment through the weighting factors.

    • Development of an oxygen consumption indicator

    t was investigated if the oxygen consumption can be used as an oxygen indicator for the Baltic Sea. The method is based on the idea of calculating the oxygen consumption in a stabile layer below the productive zone during summer and relating this to nutrient concentrations. With more nutrients available there is an increased biological production. By estimating how much oxygen is needed to mineralise the biological material it may be possible to link the oxygen consumption to eutrophication. The oxygen consumption was calculated for the BY15-Gotland Deep in the Eastern Gotland Basin. We identified a stabile layer between 30 and 50 m and a large change in both oxygen and nutrients from June to August. However, the oxygen consumption had a very high inter-annual variation and there were no significant correlation with the winter mean of nutrient concentrations. It was not possible to calculate the diffusion between the layers because of too sparse measurements at the stratification which limits the method. The calculation of the diffusion is however possible to improve with a model. Further on, the depth of the stabile layer is varying between areas and also between years.  We realised that the method has too many restrictions to be a functional indicator. A functional indicator shall not be dependent on heavy modelling or demand too much on expert judgement. 

    We also investigated if a possible candidate to use as a more simple oxygen consumption indicator could be the use of oxygen saturation at a specific depth. If we assume that the temperature has not changed much since the establishment of stratification we may expect that changes in oxygen saturation observed in August at this depth would be caused by the biological oxygen consumption occurring during late spring and summer. The correlation with winter mean nutrients slightly improved in this case.

  • 426.
    Wesslander, Karin
    et al.
    SMHI, Core Services.
    Andersson, Lars
    SMHI, Core Services.
    Axe, Philip
    SMHI, Research Department, Oceanography.
    Johansson, Johannes
    SMHI, Core Services.
    Linders, Johanna
    SMHI, Core Services.
    Nexelius, Nils
    SMHI, Core Services.
    Skjevik, Ann-Turi
    SMHI, Core Services.
    Swedish National Report on Eutrophication Status in the Skagerrak, Kattegat and the Sound - OSPAR ASSESSMENT 20162017Report (Other academic)
    Abstract [en]

    The Swedish OSPAR waters were assessed by applying the OSPAR Common Procedure for the time period 2006 – 2014. The Swedish parts of Skagerrak, Kattegat and the Sound constitute the outer part of the transition zone between the estuarine Baltic Sea and the oceanic North Sea and were investigated for nutrients, chlorophyll-a,oxygen, macrophytes, phytoplankton and zoobenthos. The conclusion from the overall assessment of the Swedish OSPAR waters was that only Skagerrak open sea could be classified as a Non-Problem Area and all other assessment units were classified as Problem Areas.  Atmospheric input of nitrogen significantly decreased in both Skagerrak and Kattegat and the land based input of total nutrients also decreased in Skagerrak, Kattegat as well as the Sound. However, the short-term trend of nitrogen input to the Sound was positive. Skagerrak is governed by trans-boundary transports from the North Sea of mainly nitrogen but also phosphorus. Kattegat receives trans-boundary nutrients from both the Baltic Sea through the Sound and from Skagerrak and transports nutrients towards the coast and the western part of the basin.  Overall, concentrations of DIN, DIP, TN and chlorophyll-a decreased in most areas, however, no significant trends were found for DIP. Increasing concentrations were found in silicate, POC and TP. The Secchi depth increased in most areas. Oxygen deficiency was mainly a problem in the fjords and the Kattegat open sea.  In Skagerrak coastal waters winter nutrients were only elevated in the fjords. Concentrations of DIN generally decreased significantly and there were tendencies of decreasing DIP. This pattern was also supported by the total nitrogen while total phosphorus increased. Secchi depth was improving and there was a significant positive trend of increasing depths. However, zoobenthos were still in bad condition and phytoplankton indicator species were often elevated. Chlorophyll-a concentrations were generally decreasing but still elevated in the inner coastal waters. There were also problems with algal toxins such as DST (Diarrhetic Shellfish Toxin) and PST (Paralystic Shellfish Toxin) infections in the area. According to the OSPAR classification scheme, a unit with no evident increased nutrient enrichment can be classified as a Problem Area but the cause might be due to trans-boundary transport from adjacent areas. In the open area of Kattegat there were still problems with oxygen deficiency, especially in the southern parts, even though the trend was significantly positive for the assessment period 2006 – 2014. Concentrations of chlorophyll-a and DIN decreased significantly, however, DIN levels were still generally elevated, especially in the southern parts of Kattegat while DIP was closer to the assessment level. In Kattegat coastal waters winter nutrients were elevated in all assessment units, except from the inner coastal waters, even though there was a general pattern of decreasing going trends. Chlorophyll-a was mainly elevated in the Sound and the estuaries. Secchi depth is generally improving and a significant increase was seen in the Sound. Also in Kattegat, zoobenthos were in bad condition and phytoplankton indicator species were often elevated. 

  • 427.
    Wesslander, Karin
    et al.
    SMHI, Core Services.
    Viktorsson, Lena
    SMHI, Core Services.
    Summary of the Swedish National Marine Monitoring 2016 - Hydrography, nutrients and phytoplankton2017Report (Other academic)
    Abstract [en]

    Results from the Swedish national marine monitoring in the pelagic during 2016 are presented. The institutes who conduct the national monitoring are SMHI (Swedish meteorological and hydrological institute), SU (Stockholm University) and UMF (Umeå marine sciences centre). The presented parameters in this report are; salinity, temperature, oxygen, dissolved inorganic phosphorous, total phosphorous, dissolved inorganic nitrogen, total nitrogen, dissolved silica, chlorophyll and phytoplankton. Secchi depth, zooplankton, humus, primary production, pH and alkalinity are also measured but not presented. Seasonal plots for surface waters are presented in Appendix I.  Time series for surface waters (0-10 m) and bottom waters are presented in Appendix II. The amount of nutrients in the sub-basins of the Baltic Sea is presented per season and year in Appendix III.Exceptional events 2016 

    • A warm September due to several high pressure systems, with temperatures more than one standard deviation above mean in almost all stations from Skagerrak, Kattegat and the Baltic Proper.
    • Low oxygen in Kattegat bottom water during autumn as can be seen in the seasonal plots for both Anholt E and Fladen.
    • Improved oxygen condition in the East Gotland Basin, due to an increased frequency of deep water inflows in comparison to the period 1983 until the large inflow in December 2014. The inflow of 30 km3 in the beginning of the year could be tracked in the deep water in the Eastern Gotland Basin in June.
    •  Elevated levels of silicate have been observed in the Baltic Sea since 2014 and the silicate levels were also elevated this year but mainly in the central and the northern parts of the Baltic Proper.
    • In July there were high cell numbers of the dinoflagellate Dinophysis acuminata, which caused high levels of toxins in blue mussels. During this period it was forbidden to harvest blue mussels along the Bohus coast.
    • Unusual long period of cyanobacteria bloom in the Baltic Sea.
  • 428.
    Wesslander, Karin
    et al.
    SMHI, Core Services.
    Viktorsson, Lena
    SMHI, Core Services.
    Fölster, Jens
    Drakare, Stina
    Sonesten, Lars
    Förslag till plan för revidering av fysikalisk-kemiska bedömningsgrunder för ekologisk status i sjöar, vattendrag och kustvatten Del A: SJÖAR OCH VATTENDRAG (SLU) Del B: KUSTVATTEN (SMHI)2017Report (Other academic)
  • 429.
    Wesslander, Karin
    et al.
    SMHI, Core Services.
    Viktorsson, Lena
    SMHI, Core Services.
    Skjevik, Ann-Turi
    SMHI, Core Services.
    The Swedish National Marine Monitoring Programme 2018. Hydrography Nutrients Phytoplankton2019Report (Other academic)
    Abstract [en]

    This report presents the main results of the Swedish national marine monitoring programme of thepelagic during 2018. The monitoring data of hydrography, nutrients and phytoplankton are analysedfor the seas surrounding Sweden: the Skagerrak, the Kattegat, the Sound, the Baltic Proper, theBothnian Sea and the Bothnian Bay.The national environmental monitoring of the pelagic is carried out by SMHI (SwedishMeteorological and Hydrological Institute), Stockholm University and UMF (Umeå Marine SciencesCentre). Data is collected, analysed and reported with support from Swedish environmentalmonitoring and on behalf of by SwAM (Swedish Agency for Marine and Water Management). TheSMHI monitoring is made in cooperation between the national environmental monitoring of thepelagic and the SMHI oceanographic sampling programme for the seas surrounding Sweden and is cofinancedby SwAM and SMHI. This annual summary of the national monitoring is made by SMHI andis financed by the contract between SwAM and SMHI.The weather in 2018 was characterized by high air temperatures and a few storms that impliedconsequences for the state in the sea. The spring arrived quickly and the sea surface temperatureincreased rapidly from April to May. In August and September two storms, named Johanne and Knud,passed the region and the surface layer was well-mixed at several stations. At the East coast upwellingevents were noted in both the Baltic Proper and the Bothnian Sea.During the year there were two small deep water inflows to the Baltic Proper that temporarilyimproved the oxygen condition in the southern parts. No improvements of the oxygen condition wereseen in the Eastern and Western Gotland Basins, instead the amount of hydrogen sulphide increased inthese basins during the year.The spring bloom had arrived in the Skagerrak and the Kattegat in March and concentrations ofdissolved inorganic phosphorus (DIP) and dissolved inorganic nitrogen (DIN) were close to or at thedetection limit from April to September. In the Skagerrak and the Kattegat the spring bloom wasdominated by the diatom Skeletonema marinoi. In the Baltic Proper the spring bloom was observed amonth later, in April. The extensive cyanobacteria bloom in the Baltic Proper started already in Mayand during the late September cruise cyanobacteria were still abundant. The dinoflagellateProrocentrum compressum was found in high cell numbers during the autumn at all stations on theWest coast. This flagellate has rarely been observed previously and although it is not harmful it isinteresting when species suddenly occur and stay for a longer period. The potentially harmful diatomgenus Pseudo-nitzschia bloomed in the beginning of December.Surface concentrations of DIP and DIN were mainly normal except from in the Skagerrak and theKattegat where concentrations were lower than usual in December. Concentrations of silicate wereabove normal levels before the spring bloom at most of the stations and in the Baltic Proper silicatewas also high in the autumn.In 2018 there were some difficulties with available research vessels for the planned cruises and somecruises needed to be cancelled with short notice. Many planned observations were therefore missed, inparticular during the summer period.

  • 430.
    Wesslander, Karin
    et al.
    SMHI, Core Services.
    Viktorsson, Lena
    SMHI, Core Services.
    Skjevik, Ann-Turi
    SMHI, Core Services.
    The SwedishNational MarineMonitoringProgramme 2017: HydrographyNutrientsPhytoplankton2018Report (Other academic)
    Abstract [en]

    This report presents the main results of the Swedish national marine monitoring programme of the pelagic during 2017. The monitoring data of hydrography, nutrients and phytoplankton are analysed for the seas surrounding Sweden: Skagerrak, Kattegat, The Sound, Baltic Proper, Bothnian Sea and Bothnian Bay. The monitoring is carried out by SMHI (Swedish Meteorological and Hydrological Institute), SU (Stockholm University) and UMF (Umeå Marine Sciences Centre) and the monitoring programme is co-funded by SwAM (Swedish Agency for Marine and Water Management), SMHI, SU and UMF. Data is collected, analysed and reported with support from Swedish environmental monitoring and commissioned by SwaM.

    The Baltic current along the Swedish west coast implies large variations in surface salinity and the unusually large outflow of brackish water from the Baltic Sea in 2017 was reflected as low surface salinity in Skagerrak and Kattegat in the beginning of the year. There were no major deep water inflows to the Baltic Sea during 2017 but a few inflows of minor magnitude. These minor inflows only temporarily improved the oxygen condition in the Bornholm Basin and in the southern part of the Eastern Gotland Basin.

    The salinity below the halocline was above normal in the Gotland Basins and in the Northern Baltic Proper, and also in the surface layer in the Eastern Gotland Basin for almost the whole year.

    In Skagerrak and Kattegat, surface concentrations of phosphate and dissolved inorganic nitrogen were normal while dissolved silica concentrations were elevated especially in spring. In the Baltic Sea, the concentration of silicate in the surface water was elevated in all basins. According to the estimated total content of silicate there has been an increase in silica content in the Baltic Sea since the early 1990’s. Surface concentrations of phosphate were above normal in the Gotland basins and the Northern Baltic Proper while inorganic nitrogen content was above normal in parts of the Arkona and Bornholm basins. During spring and summer, the inorganic nitrogen was consumed at greater depths than usual in the Baltic Proper. In particular concentrations of phosphate and dissolved silica were generally lower than normal in the bottom layer.

    Instead of diatoms, the flagellate genus Pseudochattonella, which is potentially toxic to fish, bloomed in the Kattegat and Skagerrak areas in February – April. During autumn there was a prolonged diatom bloom though. In the Baltic Sea spring bloom occurred in April. The cyanobacteria bloom began in May already with Aphanizomenon flos-aquae. During June and July all three of the filamentous cyanobacteria, A. flos-aquae, Dolichospermum lemmermannii and the potentially harmful Nodularia spumigena were found in the phytoplankton samples in various amounts.

    In the Bothnian Sea, the sea surface temperature during summer was lower than normal and the oxygen conditions in the bottom layer was not critical but still below normal levels.

  • 431.
    Westring, Gustaf
    et al.
    SMHI.
    Andersson, Jan
    SMHI, Core Services.
    Lindh, Henrik
    SMHI, Core Services.
    Axelsson, Robert
    SMHI.
    Forsmark - en temperaturstudie: Slutrapport1993Report (Other academic)
  • 432.
    Wickström, Kjell
    et al.
    SMHI.
    Hillgren, Robert
    SMHI, Core Services.
    Spridningsberäkningar för EKA-NOBELs fabrik i Stockviksverken1990Report (Other academic)
  • 433. Wilk, J.
    et al.
    Andersson, Lotta
    SMHI, Core Services. SMHI, Research Department, Hydrology.
    Graham, Phil
    SMHI, Professional Services.
    Wikner, J. J.
    Mokwatlo, S.
    Petja, B.
    From forecasts to action - What is needed to make seasonal forecasts useful for South African smallholder farmers?2017In: International Journal of Disaster Risk Reduction, E-ISSN 2212-4209, Vol. 25, p. 202-211Article in journal (Refereed)
  • 434.
    Wilk, Julie
    et al.
    SMHI, Research Department, Hydrology.
    Andersson, Lotta
    SMHI, Core Services.
    Warburton, Michele
    Adaptation to climate change and other stressors among commercial and small-scale South African farmers2013In: Regional Environmental Change, ISSN 1436-3798, E-ISSN 1436-378X, Vol. 13, no 2, p. 273-286Article in journal (Refereed)
    Abstract [en]

    Commercial and small-scale farmers in South Africa are exposed to many challenges. Interviews with 44 farmers in the upper Thukela basin, KwaZulu-Natal, were conducted to identify common and specific challenges for the two groups and adaptive strategies for dealing with the effects of climate and other stressors. This work was conducted as part of a larger participatory project with local stakeholders to develop a local adaptation plan for coping with climate variability and change. Although many challenges related to exposure to climate variability and change, weak agricultural policies, limited governmental support, and theft were common to both farming communities, their adaptive capacities were vastly different. Small-scale farmers were more vulnerable due to difficulties to finance the high input costs of improved seed varieties and implements, limited access to knowledge and agricultural techniques for water and soil conservation and limited customs of long-term planning. In addition to temperature and drought-related challenges, small-scale farmers were concerned about soil erosion, water logging and livestock diseases, challenges for which the commercial farmers already had efficient adaptation strategies in place. The major obstacle hindering commercial farmers with future planning was the lack of clear directives from the government, for example, with regard to issuing of water licences and land reform. Enabling agricultural communities to procure sustainable livelihoods requires implementation of strategies that address the common and specific challenges and strengthen the adaptive capacity of both commercial and small-scale farmers. Identified ways forward include knowledge transfer within and across farming communities, clear governmental directives and targeted locally adapted finance programmes.

  • 435.
    Wilk, Julie
    et al.
    SMHI, Research Department, Hydrology.
    Jonsson, Anna
    SMHI, Core Services.
    Rydhagen, Birgitta
    Rani, Ashu
    Kumar, Arun
    The perspectives of the urban poor in climate vulnerability assessments - The case of Kota, India2018In: Urban Climate, ISSN 2212-0955, E-ISSN 2212-0955, Vol. 24, p. 633-642Article in journal (Refereed)
  • 436. Wilk, Julie
    et al.
    Kniveton, Dominic
    Andersson, Lotta
    SMHI, Core Services.
    Layberry, Russell
    Todd, Martin C.
    Hughes, Denis
    Ringrose, Susan
    Vanderpost, Cornelis
    Estimating rainfall and water balance over the Okavango River Basin for hydrological applications2006In: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 331, no 1-2, p. 18-29Article in journal (Refereed)
    Abstract [en]

    A historical database for use in rainfall-runoff modeling of the Okavango River Basin in Southwest Africa is presented. The work has relevance for similar data-sparse regions. The parameters of main concern are rainfall and catchment water balance, which are key variables for subsequent studies of the hydrological impacts of development and climate change. Rainfall estimates are based on a combination of in situ gauges and satellite sources. Rain gauge measurements are most extensive from 1955 to 1972, after which they are drastically reduced due to the Angolan civil war. The sensitivity of the rainfall fields to spatial interpolation techniques and the density of gauges were evaluated. Satellite based rainfall estimates for the basin are developed for the period from 1991 onwards, based on the Tropical Rainfall Measuring Mission (TRMM) and Special Sensor Microwave Imager (SSM/I) datasets. The consistency between the gauges and satellite estimates was considered. A methodology was developed to allow calibration of the rainfall-runoff hydrological model against rain gauge data from 1960 to 1972, with the prerequisite that the model should be driven by satellite derived rainfall products from ` 1990 onwards. With the rain gauge data, addition of a single rainfall station (Longa) in regions where stations earlier were lacking was more important than the chosen interpolation method. Comparison of satellite and gauge rainfall outside the basin indicated that the satellite overestimates rainfall by 20%. A non-linear correction was derived by fitting the rainfall frequency characteristics to those of the historical rainfall data. This satellite rainfall dataset was found satisfactory when using the Pitman rainfall-runoff model (Hughes, D., Andersson, L., Wilk, J., Savenije, H.H.G., this issue. Regional calibration of the Pitman model for the Okavango River. Journal of Hydrology). Intensive monitoring in the region is recommended to increase accuracy of the comprehensive satellite rainfall estimate calibration procedure. (c) 2006 Elsevier B.V. All rights reserved.

  • 437. Wolski, Tomasz
    et al.
    Wisniewski, Bernard
    Giza, Andrzej
    Kowalewska-Kalkowska, Halina
    Boman, Hanna
    Grabbi-Kaiv, Silve
    Hammarklint, Thomas
    SMHI, Core Services.
    Holfort, Juergen
    Lydeikaite, Zydrune
    Extreme sea levels at selected stations on the Baltic Sea coast2014In: Oceanologia, ISSN 0078-3234, Vol. 56, no 2, p. 259-290Article in journal (Refereed)
    Abstract [en]

    The purpose of this article is to analyse and describe the extreme characteristics of the water levels and illustrate them as the topography of the sea surface along the whole Baltic Sea coast. The general pattern is to show the maxima and minima of Baltic Sea water levels and the extent of their variations in the period from 1960 to 2010. A probability analysis is carried out on the annual sea level maxima and minima for 31 water level gauges in order to define the probability of occurrence of theoretical sea levels once in a specific number of years. The spatial distribution of sea levels for hundred-year maximum and minimum water levels is illustrated. Then, the number of storm surges for the accepted criteria are presented: these numbers increased in the 50-year period analysed. The final part of the work analyses some extreme storm events and calculates the static value and dynamic deformation of the sea surface by mesoscale, deep low-pressure systems.

  • 438. Wu, Minchao
    et al.
    Schurgers, Guy
    Rummukainen, Markku
    SMHI, Core Services.
    Smith, Benjamin
    Samuelsson, Patrick
    SMHI, Research Department, Climate research - Rossby Centre.
    Jansson, Christer
    Siltberg, Joe
    May, Wilhelm
    Vegetation-climate feedbacks modulate rainfall patterns in Africa under future climate change2016In: Earth System Dynamics, ISSN 2190-4979, E-ISSN 2190-4987, Vol. 7, no 3, p. 627-647Article in journal (Refereed)
  • 439.
    Yacoub, Tahsin
    et al.
    SMHI, Core Services.
    Sanner, Håkan
    SMHI, Core Services.
    Vattenståndsprognoser baserade på översiktlig kartering: En fallstudie2006Report (Other academic)
    Abstract [sv]

    Räddningsverket,numera MSB, (Myndigheten för Samhällsskydd och Beredskap) finansierar forskningsprojektet ”Översvämningsprognoser - Utveckling av metoder för ett rikstäckande system” som bedrivs på SMHI. Den här rapporten redovisar resultaten från delprojektet ”Vattenståndsprognoser”. Projektet syfte har varit att i fallstudier utvärdera i vilka typer av vattendrag som översiktliga data ger en tillräcklig noggrannhet i prognosticerat vattenstånd. Fallstudier har genomförts för Byälven, Emån, Eskilstunaån och Lagan vid Ljungby. Ursprungligen var det tänkt att den geografiska spridningen skulle vara större, men tillgången på data har fått styra valet av områden. I Byälven och Emån har den hydrauliska modellen, som användes vid Räddningsverkets (numera MSB, Myndigheten för Samhällsskydd och Beredskap), översiktliga översvämningskartering, jämförts med observerade vattenstånd som inte använts vid kalibreringen. För Eskilstunaån och Lagan vid Ljungby har detaljerade hydrauliska modeller satts upp efter det att den översiktliga hydrauliska modellen gjordes. Dessa har här använts i stället för mätningar för att uppskatta vilken noggrannhet den översiktliga hydrauliska modellen ger och hur den skulle kunna förbättras under ett flöde genom korrigering/ uppdatering mot uppmätta värden.Resultaten visar att den översiktliga hydrauliska modellen oftast ger förvånansvärt bra noggrannhet, men stora fel kan finnas på enstaka platser. Brist på regleringsuppgifter och osäkerheter vattenföringsprognoser har oftast större betydelse för osäkerheten i vattenståndsprognoserna än brist i noggrannhet i den översiktliga hydrauliska modellen. De tankar som finns om att låta räddningstjänsten observera vattenstånd vid broar under ett flöde för att förbättra vattenståndsprognoserna får stöd av resultaten.

  • 440.
    Yacoub, Tahsin
    et al.
    SMHI, Core Services.
    Westman, Ylva
    SMHI, Core Services.
    Sanner, Håkan
    SMHI, Core Services.
    Samuelsson, Bernth
    SMHI, Core Services.
    Detaljerad översvämningskarta för Eskilstunaån. Ett projekt inom KRIS-GIS2005Report (Other academic)
    Abstract [sv]

    SMHI har gjort en detaljerad översvämningskarta för en 23 km lång sträcka längs Eskilstunaån, från utloppet av Närsjöfjärden och ned till mynningen i Mälaren. Arbetet har drivits som ett projekt inom KRIS-GIS ® och finansierats till hälften av KBM (via Lantmäteriets Totalförsvarsenhet) och till häften av SMHI. En jämförelse mellan den framtagna detaljerade översvämningskarteringen och den av Räddningsverket (numera MSB, Myndigheten för Samhällsskydd och Beredskap) finansierade översiktliga översvämningskarteringen för Eskilstunaån har också genomförts. En laserskannad höjdmodell med hög noggrannhet har tagits fram och en ekolodning av Eskilstunaån har genomförts. Med bland annat detta underlagsmaterial har den detaljerade karteringen genomförts. De hydrauliska beräkningarna har förbättrats av den mer detaljerade höjddatabasen och djupmätningarna. Vattenståndsberäkningarna i den översiktliga översvämningskarteringen är oftast förvånansvärt bra, men stora fel kan finnas på kortare sträckor längs vattendraget. Det beror på och är beroende av mängden och kvalitén på extrainformationen som inhämtas, såsom broritningar, dammuppgifter, vattenståndsuppgifter från tidigare flöden och tidigare inventeringar. De översvämmade områdena skiljer relativt mycket mellan den detaljerade och den översiktliga översvämningskarteringen. Den huvudsakliga orsaken är skillnaden mellan höjddatabaserna.

  • 441. Zerefos, Christos S.
    et al.
    Eleftheratos, Kostas
    Kapsomenakis, John
    Solomos, Stavros
    Inness, Antje
    Balis, Dimitris
    Redondas, Alberto
    Eskes, Henk
    Allaart, Marc
    Amiridis, Vassilis
    Dahlback, Arne
    De Bock, Veerle
    Diemoz, Henri
    Engelmann, Ronny
    Eriksen, Paul
    Fioletov, Vitali
    Grobner, Julian
    Heikkila, Anu
    Petropavlovskikh, Irina
    Jaroslawski, Janusz
    Josefsson, Weine
    SMHI, Core Services.
    Karppinen, Tomi
    Koehler, Ulf
    Meleti, Charoula
    Repapis, Christos
    Rimmer, John
    Savinykh, Vladimir
    Shirotov, Vadim
    Siani, Anna Maria
    Smedley, Andrew R. D.
    Stanek, Martin
    Stubi, Rene
    Detecting volcanic sulfur dioxide plumes in the Northern Hemisphere using the Brewer spectrophotometers, other networks, and satellite observations2017In: Atmospheric Chemistry And Physics, ISSN 1680-7316, E-ISSN 1680-7324, Vol. 17, no 1, p. 551-574Article in journal (Refereed)
  • 442. Zhang, Daoxi
    et al.
    Lavender, Samantha
    Muller, Jan-Peter
    Walton, David
    Karlson, Bengt
    SMHI, Research Department, Oceanography.
    Kronsell, Johan
    SMHI, Core Services.
    Determination of phytoplankton abundances (Chlorophyll-a) in the optically complex inland water - The Baltic Sea2017In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 601, p. 1060-1074Article in journal (Refereed)
6789 401 - 442 of 442
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