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Johansson, Barbro
Publications (10 of 22) Show all publications
Berglöv, G., German, J., Gustavsson, H., Harbman, U. & Johansson, B. (2009). Improvement HBV model Rhine in FEWS: Final report. SMHI
Open this publication in new window or tab >>Improvement HBV model Rhine in FEWS: Final report
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2009 (English)Report (Other academic)
Abstract [en]

Between 1997 and 2004, the German Federal Institute of Hydrology (BfG), in cooperation with the Dutch Rijkswaterstaat Waterdienst, set up and calibrated the HBV rainfall-runoff model for the river Rhine. The model performed well for its original purpose, but less well when it was incorporated in the forecasting system FEWS in 2005. The main reason for the deteriorating performance was that the precipitation, temperature and evaporation data available for real-time applications differed from the ones used for the calibration. Another problem was that the accuracy in the low flow simulations was considered inadequate for navigation forecasts. It was thus decided that the HBV model set-up for Rhine should be updated and expanded in its functionalities primarily for use in operational forecasting. The tasks given to SMHI were:· To evaluate the evaporation calculations in HBV and recommend the best one to be used in the forecasting application.· To recalibrate the model using operationally available input data and with the aim to adequately model the whole range of flows.· To activate the HBV routine for updating model state variables before a forecast (PT updating)A new precipitation and temperature data set was provided for the calibration. This data set is consistent with the data to be used in the forecasting application, but improved as compared to the first data set used in the FEWS-DE system. To improve low flow simulations, a new model option, the contributing area approach, was used. The model was recalibrated using an automatic routine. Some minor manual parameter adjustments were made in a few sub-catchments, mainly to correct for anthropogenic influences and backwater effects on discharge measurements. The calibration was done locally for some 95 sub catchments, and verified both locally and for the total river flow.The overall model performance after recalibration with the new input data was at least as good as for the original calibration. Low flow recession and variations were reproduced to a greater degree. An evaluation with the old parameters and the new input data showed that the new data set in itself was not enough for satisfactory model performance. The recalibration was necessary. PT updating was shown to improve the forecast accuracy both for low/intermediate flows and for high flows. The effect diminishes with forecast lead time, but still remains at least up to the fifth day.

Place, publisher, year, edition, pages
SMHI, 2009. p. 66
Series
Hydrology, ISSN 0283-7722 ; 112
Identifiers
urn:nbn:se:smhi:diva-2789 (URN)Hydrologi, Rapporter, Serie Hydrologi (Local ID)Hydrologi, Rapporter, Serie Hydrologi (Archive number)Hydrologi, Rapporter, Serie Hydrologi (OAI)
Available from: 2009-09-23 Created: 2016-07-08 Last updated: 2016-07-08Bibliographically approved
Johansson, B., Lindström, G., Olsson, J., Yacoub, T., Haase, G., Jacobsson, K. & Sanner, H. (2007). Översvämningsprognoser i områden med ofullständiga data: Metodutveckling och utvärdering. SMHI
Open this publication in new window or tab >>Översvämningsprognoser i områden med ofullständiga data: Metodutveckling och utvärdering
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2007 (Swedish)Report (Other academic)
Abstract [sv]

Rapporten redovisar slutresultat från projektet ”Översvämningsprognoser Utveckling av metoder för ett rikstäckande system för vattenförings- och vattenståndsprognoser”. Projektet har i huvudsak varit finansierat av Räddningsverket, numera MSB, (Myndigheten för Samhällsskydd och Beredskap), men har även utnyttjat resultat från näraliggande projekt finansierade av Elforsk, SMHI och EU.I ett rikstäckande system måste prognoser göras för vattendrag där det saknas detaljerad information om avrinningsområdets och älvfårans egenskaper. Modeller kan inte tillämpas och verifieras på samma sätt som i områden med god datatillgång och tillgång till tidsserier med observerad vattenföring. Eftersom beräkningarna inte kan verifieras mot observationer blir det extra viktigt med bra nederbördsinformation och att kunna ge ett mått på osäkerheten i prognosen. Projektet har dels arbetat med metodutveckling, dels med en omfattande utvärdering av data och beräkningsresultat. En pilotstudie gjordes för flödet sommaren 2004 i Lagan/Ljungby. Fokus har varit på följande områden:- Utveckling och utvärdering av en metodik för att utnyttja meteorologiska och hydrologiska sannolikhetsprognoser- Utvärdering och minimering av osäkerheten i hydrologiska (vattenföring) och hydrauliska (vattenstånd) prognosmodeller.- Utveckling och utvärdering av metoder för att utnyttja radarobservationer av nederbörd.Projektet har visat att det är möjligt att göra vattenståndsprognoser med rimlig noggrannhet, utgående från data som finns tillgängliga i ett rikstäckande system. Tillgång till bra nederbördsinformation för dagarna före prognosen är viktig, speciellt i sjörika system med ett långsamt förlopp. För att kunna göra sannolikhetsprognoser räcker det inte att ta hänsyn till osäkerheten i den meteorologiska prognosen genom att direkt utnyttja meteorologiska ensembleprognoser. Spridningen i de meteorologiska nederbördsprognoserna är inte tillräcklig och osäkerheten i den hydrologiska modellen måste beaktas.De projektresultat som inom det närmaste året kommer att utnyttjas i ett rikstäckande system är de som är relaterade till hydrologisk modellering och sannolikhetsprognoser. Arbetet med att utveckla metoder för att utnyttja radarinformation i operationell skattning av arealnederbörd fortgår. Fallstudier har visat att vattenståndsprognoser kan göras med modeller baserad på översiktlig information om topografi och tvärsektioner i vattendragen. Däremot är det tidsödande att sätta upp en hydraulisk modell för en godtycklig älvsträcka. Tills vidare är det realistiskt att anta att vattenståndsprognoser främst kommer att göras i vattendrag som ingått i den översiktliga översvämningskarteringen.

Place, publisher, year, edition, pages
SMHI, 2007. p. 65
Series
Hydrology, ISSN 0283-7722 ; 104
Identifiers
urn:nbn:se:smhi:diva-2267 (URN)Hydrologi, Rapporter, Serie Hydrologi (Local ID)Hydrologi, Rapporter, Serie Hydrologi (Archive number)Hydrologi, Rapporter, Serie Hydrologi (OAI)
Available from: 2007-04-29 Created: 2016-07-08 Last updated: 2016-07-08Bibliographically approved
Johansson, B. & Chen, D. L. (2005). Estimation of areal precipitation for runoff modelling using wind data: a case study in Sweden. Climate Research (CR), 29(1), 53-61
Open this publication in new window or tab >>Estimation of areal precipitation for runoff modelling using wind data: a case study in Sweden
2005 (English)In: Climate Research (CR), ISSN 0936-577X, E-ISSN 1616-1572, Vol. 29, no 1, p. 53-61Article in journal (Refereed) Published
Abstract [en]

In mountainous regions, rainfall distribution is influenced by topography in combination with wind speed and direction. This has implications for estimates of catchment precipitation as input to hydrological models. The objective of this work was to investigate if wind information can be used to improve the accuracy of precipitation estimates, particularly for operational applications. A geostrophic wind, computed from pressure observations, was assumed to represent the airflow at an altitude relevant for precipitation distribution. Interpolated values of precipitation (optimal interpolation) were verified directly against point observations. In some mountainous catchments with low annual evapotranspiration, estimates of long-term mean areal precipitation could be verified through the water balance equation. The effects of the interpolations with and without wind information on the performance of a rainfall-runoff model were also investigated. There were 2 main factors in favour of using wind information in the interpolation: (1) a better description of the seasonal distribution; and (2) a lower sensitivity to reductions in the number of meteorological stations.

Keywords
areal precipitation, orographic enhancement, interpolation, rainfall-runoff modelling, spatial distribution, airflow, Sweden
National Category
Oceanography, Hydrology and Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:smhi:diva-1269 (URN)10.3354/cr029053 (DOI)000231971900005 ()
Available from: 2015-07-27 Created: 2015-05-26 Last updated: 2018-01-11Bibliographically approved
Johansson, B., Andréasson, J. & Jansson, J. (2003). Satellite data on snow cover in the HBV model: Method development and evaluation. SMHI
Open this publication in new window or tab >>Satellite data on snow cover in the HBV model: Method development and evaluation
2003 (English)Report (Other academic)
Abstract [en]

Hydrological forecasts are essential, both for the prevention of flood damages and for water resources planning. In Northern Sweden, snowmelt plays an important role in the formation of runoff. Spring flood forecasts have been carried out since the middle of the 1970s, using the HBV runoff model. In the HBV model, the snow pack is simulated from interpolated daily observations of point precipitation and temperature. The acquirement of representative data is often difficult as the highest precipitation occurs at high altitudes, which are sparsely populated and difficult to reach. Remote sensing data on the snow pack should thus be important as an additional source of information. The project presented in this report had two aims:- To modify the HBV model to include remote sensing data as input to the simulations.- To evaluate the influence of such data on the accuracy of simulated runoff.The remote sensing data available to the project came from NOAA-AVHRR images, which provided data on snow covered area under cloud free conditions. The evaluation was carried out for a medium-sized catchment in the mountainous region in the northwest of Sweden. Satellite data were available for five different years. To facilitate the use of remote sensing data, a gridded version of the HBV model was developed. Procedures and criteria were developed to automatically calibrate the HBV model against both runoff and snow cover data. This was done to minimise the risk of compensating errors in the parameter values of the model.Due to clouds, remote sensing data are not available on a regular basis. Consequently they were not utilised as model input in the same sense as precipitation and temperature. When available, they were instead used to correct errors in the simulated snow pack. Model routines were developed to compare observed and simulated snow cover and to automatically make the corrections.For the evaluation, the data set was divided into two periods. The model was calibrated independently for each period and verified for the other. The results were contradictory and not conclusive. For the first period, the precipitation appeared to be systematically overestimated, which led to compensating errors in the parameter fitting and an erroneously modelled snow distribution. Attempts to correct the snow pack for the second period thus failed. For the second period, there were no apparent systematic errors in the precipitation input. After calibrating the model for this period, satellite data could be used to considerably improve the accuracy in the runoff simulations for the first period. The overestimation of precipitation and thereby the snow pack could be corrected for.The most effective way to overcome the problem of systematic errors in the input data for the calibration period is longer data records. Another possibility is more sophisticated calibration routines than the ones developed within this project. A grid by grid comparison of modelled and observed snow cover showed systematic deviations. It indicates that there are improvements to be made in the snow model, and that remote sensing data can be useful in such work

Place, publisher, year, edition, pages
SMHI, 2003. p. 19
Series
Hydrology, ISSN 0283-7722 ; 90
Identifiers
urn:nbn:se:smhi:diva-2313 (URN)Hydrologi, Rapporter, Serie Hydrologi (Local ID)Hydrologi, Rapporter, Serie Hydrologi (Archive number)Hydrologi, Rapporter, Serie Hydrologi (OAI)
Available from: 2003-05-05 Created: 2016-07-08 Last updated: 2016-07-08Bibliographically approved
Chen, D. & Johansson, B. (2003). Temperaturens höjdberoende: En studie i Indalsälvens avrinningsområde. SMHI
Open this publication in new window or tab >>Temperaturens höjdberoende: En studie i Indalsälvens avrinningsområde
2003 (Swedish)Report (Other academic)
Abstract [sv]

Vid modellering av snösmältning och snöackumulation är temperaturen en viktig variabel. De lokala variationerna i temperaturen styrs till stor del av höjden över havet. Denna rapport redovisar ett projekt som haft till syfte att förbättra beskrivningen av temperaturens höjdberoende i de indata som används för att simulera avrinning med HBV-modellen. Studien har omfattat de övre delarna av Indalsälvens avrinningsområde. För att analysera variationerna i höjdberoendet prövades två angreppssätt:- En statistisk analys av observerade data vid de meteorologiska stationerna.- Simuleringar med en högupplöst meteorologisk modell.Syftet med att använda en meteorologisk modell var att den ger en mer komplett bild av temperaturvariationerna än stationerna som bara representerar en liten del av området.Den statistiska analysen av stationsdata visade en årstidsvariation i temperaturens höjdberoende. Snabbast avtog temperaturen med höjden under försommaren, medan man i snitt hade en svag ökning av temperaturen med höjden runt årskiftet. Studien visade också ett tydligt samband mellan temperatur och höjdberoende, vilket innebar att säsongsvariationen delvis förklarades av temperaturens årscykel. Under senvåren då en stor del av snösmältningen sker, låg temperaturavtagandet i snitt mycket nära 0.6oC/100m.Testerna med den meteorologiska modellen indikerade att det är ett angreppssätt som kan användas för att i detalj beskriva temperaturens variationer i ett område med komplex topografi, men att mer djupgående studier krävs för att fullt ut tolka modellresultaten. Generellt var höjdberoendet i modellen betydligt flackare än det som togs fram från stationsdata.Ur stationsdata togs ett enkelt samband fram för att beskriva temperaturens höjdberoende som en funktion av temperatur och tid på året. Sambandet användes sedan vid interpolation av temperatur och för simuleringar i HBV-modellen. En korsvalidering med stationsdata visade att ett variabelt höjdberoende gav en bättre skattning av temperaturen än ett konstant höjdavtagande. Förbättringen var störst under vintermånaderna och för högt belägna stationer.Trots att korsvalideringen visade bättre resultat med ett variabelt höjdberoende, blev det inga förbättringar av den simulerade avrinningen i HBV-modellen. Beskrivningen av höjdberoendet påverkade dock snöns fördelning i modellen. Även om det inte direkt har effekt på den simulerade avrinningen, så får det därför betydelse om man exempelvis vill uppdatera simulerat snömagasin från observationer.Slutsatsen från studien är att det idag inte finns skäl att ändra beskrivningen av temperaturens höjdberoende i HBV-modellen. Däremot bör modellen hållas öppen för ett variabelt höjdberoende i framtiden då nya typer av indata och uppdatering av snömagasinet kan bli aktuellt. Det samband som tagits fram för höjdberoendet är lätt att applicera och ger en bättre skattning av temperaturen än ett konstant höjdberoende.

Place, publisher, year, edition, pages
SMHI, 2003. p. 19
Series
Hydrology, ISSN 0283-7722 ; 88
Identifiers
urn:nbn:se:smhi:diva-2279 (URN)Hydrologi, Rapporter, Serie Hydrologi (Local ID)Hydrologi, Rapporter, Serie Hydrologi (Archive number)Hydrologi, Rapporter, Serie Hydrologi (OAI)
Available from: 2003-04-29 Created: 2016-07-08 Last updated: 2016-07-08Bibliographically approved
Johansson, B. & Chen, D. L. (2003). The influence of wind and topography on precipitation distribution in Sweden: Statistical analysis and modelling. International Journal of Climatology, 23(12), 1523-1535
Open this publication in new window or tab >>The influence of wind and topography on precipitation distribution in Sweden: Statistical analysis and modelling
2003 (English)In: International Journal of Climatology, ISSN 0899-8418, E-ISSN 1097-0088, Vol. 23, no 12, p. 1523-1535Article in journal (Refereed) Published
Abstract [en]

To estimate daily catchment precipitation from point observations there is a need to understand the spatial pattern, particularly in mountainous regions. One of the most important processes occurring there is orographic enhancement, which is affected by, among other things, wind speed and wind direction. The objective of this paper was to investigate whether the relationship between precipitation, airflow and topography could be described by statistical relationships using data easily available in an operational environment. The purpose was to establish a statistical model to describe basic patterns Of precipitation distribution. This model, if successful, can he used to account for the topographical influence in precipitation interpolation schemes. A statistical analysis was carried out to define the most relevant variables, and, based on that analysis, a regression model was established through stepwise regression. Some 15 years of precipitation data front 370 stations in Sweden were used for the analysis. The geostrophic wind, computed from pressure observations, was assumed to represent the airflow at the relevant altitude. Precipitation data for each station were divided into 48 classes representing different wind directions and wind speeds. Among the variables selected, the single most important one was found to be the location of a station with respect to a mountain range. On the upwind side, precipitation increased with increasing wind speed. On the leeward side there was less variation in precipitation, and wind speed did not affect the precipitation amounts to the same degree. For ascending air, slope multiplied by wind speed was another important factor. The effect of slope was enhanced close to the coast, and reduced for mountain valleys with upwind barriers. The stepwise procedure led to a regression model that also included the meridional and zonal wind components. Their inclusion might indicate the importance of air mass characteristics not explicitly accounted for. Copyright (C) 2003 Royal Meteorological Society.

Keywords
precipitation, orographic enhancement, regression analysis, topography, airflow, spatial distribution, Sweden
National Category
Oceanography, Hydrology and Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:smhi:diva-1339 (URN)10.1002/joc.951 (DOI)000186114100007 ()
Available from: 2015-08-17 Created: 2015-07-29 Last updated: 2018-01-11Bibliographically approved
Pettersson, A., Arheimer, B. & Johansson, B. (2001). Nitrogen concentrations simulated with HBV-N: New response function and calibration strategy - Paper presented at the Nordic Hydrological Conference (Uppsala, Sweden June, 2000). Nordic Hydrology, 32(3), 227-248
Open this publication in new window or tab >>Nitrogen concentrations simulated with HBV-N: New response function and calibration strategy - Paper presented at the Nordic Hydrological Conference (Uppsala, Sweden June, 2000)
2001 (English)In: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 32, no 3, p. 227-248Article in journal (Refereed) Published
Abstract [en]

HBV-N is a conceptual process-based model for simulation of transformation and transport of nitrogen on the catchment scale. This paper presents further development with focus on the response function and calibration procedures. Evaluation of the model routines was made in 12 test basins in southern Sweden (without or with only few lakes). Previous versions of HBV-N included a HBV version with a single reservoir in the response function. The presented results show that both nitrogen concentrations and water discharge simulations improved when a second reservoir was introduced. The two-reservoir model was found to be more well-posed for description of residence-times and flow paths. On average, this resulted in an increase in explained variance (R-2) for nitrogen concentrations by 0.3. Multiple-response split-sample calibration was found to further improve the model performance and reliability. In previous applications HBV-N has been applied by using single-response calibration. However, simultaneous calibration of water discharge and nitrogen improved the R2 for nitrogen concentrations by about 0.1 (range 0.02-0.25), but did not affect the simulation of water discharge. This new calibration strategy forces the hydrological parameters to a new optimum, and reduces the level of uncertainty for both hydrochemical and hydrological modelling.

National Category
Oceanography, Hydrology and Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:smhi:diva-1493 (URN)000171692200005 ()
Available from: 2015-08-24 Created: 2015-08-17 Last updated: 2018-01-11Bibliographically approved
Andréasson, J., Gyllander, A., Johansson, B., Källgården, J., Lindell, S. & Olofsson, J. (2001). Snötaxering med georadar: Bättre vårflödesprognoser med HBV-modellen?. SMHI
Open this publication in new window or tab >>Snötaxering med georadar: Bättre vårflödesprognoser med HBV-modellen?
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2001 (Swedish)Report (Other academic)
Abstract [sv]

Denna studie hade som målsättning att undersöka möjligheten att med hjälp av georadarmätningar korrigera HBV-modellens snömagasin och därigenom öka tillförlitligheten för vårflödesprognoserna.Två angreppssätt har testats för att korrigera HBV-modellens snömagasin mot snötaxeringsdata. Dels gjordes försök att finna representativa flyglinjer som, via linjär regression mot HBV-modellens uppdaterade snömagasin, kunde representera områdets verkliga snömagasin. Dels enomfördes försök att utifrån flyglinjerna och geografiska variabler interpolera fram ett arealmedelvärde för snömagasinet i prognosområdena.Resultaten från den förstnämnda metoden visar att den extra informationen kan vara av värde i områden där HBV-modellen uppvisar systematiska fel. Georadardata kan därför användas för att upptäcka och korrigera för homogenitetsbrott i klimatdata. I områden där HBVmodellens fel tycks slumpmässiga verkar däremot inte georadardata förbättra prognoserna. Försöken med ett interpolerat snömagasin gav inte resultat som ansågs tillräckligt bra för att kunna användas för uppdatering av HBV-modellen.I de flesta områden är HBV-modellens volymfel över vårfloden små (< 10%) vilket ställer höga krav på mätningarnas kvalité för att de ska kunna användas för att ytterligare förbättra prognoserna. Svårigheterna att förbättra HBV-modellens vårflödesprognoser kan dels ha varit beroende på att HBV-modellens struktur inte är anpassad till att utnyttja denna typ av indata och dels på att kvalitén på mätningarna inte var tillräcklig i förhållande till HBV-modellens precision. Snöns spatiala densitetsvariationer, snöns våthet och koordinatbestämningen av mätpunkterna har identifierats som kritiska för noggrannheten på det beräknade snömagasinets storlek. I rapporten har rekommendationer givits för hur dessa problem skulle kunna behandlas.

Place, publisher, year, edition, pages
SMHI, 2001. p. 21
Series
Hydrology, ISSN 0283-7722 ; 87
Identifiers
urn:nbn:se:smhi:diva-2280 (URN)Hydrologi, Rapporter, Serie Hydrologi (Local ID)Hydrologi, Rapporter, Serie Hydrologi (Archive number)Hydrologi, Rapporter, Serie Hydrologi (OAI)
Available from: 2001-04-29 Created: 2016-07-08 Last updated: 2016-07-08Bibliographically approved
Johansson, B. (2000). Areal precipitation and temperature in the Swedish mountains - An evaluation from a hydrological perspective. Nordic Hydrology, 31(3), 207-228
Open this publication in new window or tab >>Areal precipitation and temperature in the Swedish mountains - An evaluation from a hydrological perspective
2000 (English)In: Nordic Hydrology, ISSN 0029-1277, E-ISSN 1996-9694, Vol. 31, no 3, p. 207-228Article in journal (Refereed) Published
Abstract [en]

This paper presents an evaluation of three different methods for estimation of areal precipitation and temperature, with special emphasis on their applicability for runoff modelling in the Swedish mountains. All three methods estimate the areal values as a weighted mean of the observations at nearby meteorological stations. The weights are determined by: 1) a manual subjective selection of the most representative stations 3) inverse square distance weighting 4) optimal interpolation. The methods were tested in an area with complex topography and precipitation gradients. The evaluation included comparison of areal estimates, verification against point observations and the water balance equation, and sensitivity analyses with respect to method parameters and network changes. The evaluation showed that for simple runoff modelling the subjective and optimal interpolation methods performed equally well, and considerably better than inverse-distance weighting. The evaluation also showed that none of the methods correctly described the spatial variation in precipitation and temperature in the investigated region. They are thus not directly applicable for nbn-routine modelling applications where the estimation of runoff is not the sole objective. All methods proved to be sensitive to the selection of parameter values, which pointed to possible improvements of the estimates. The optimal interpolation method seemed to be the least sensitive to changes in the meteorological network.

National Category
Oceanography, Hydrology and Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:smhi:diva-1521 (URN)000089889800004 ()
Available from: 2015-08-18 Created: 2015-08-17 Last updated: 2018-01-11Bibliographically approved
Johansson, B. (2000). Precipitation and Temperature in the HBV Model: A Comparison of Interpolation Methods. SMHI
Open this publication in new window or tab >>Precipitation and Temperature in the HBV Model: A Comparison of Interpolation Methods
2000 (English)Report (Other academic)
Abstract [en]

This report presents an evaluation of three different methods for estimation of areal precipitation and temperature

, with

special emphasis on their applicability for runoff modelling in the Scandinavian mountains. All three methods estimate

the areal values as a weighted mean of the observations at nearby meteorological stations. The weights are determined

by:

a)

a manual subjective selection of the most representative stations

b)

inverse square distance weighting

c)

optimal interpolation

The methods were tested for a mountainous region in the north-western part of Sweden, which is an area with few

meteorological stations and complex precipitation gradients. The elevation range is some 1500m

, but meteorological

stations are normally located at low altitudes in the valleys. For the subjective and inverse distance weighting methods,

precipitation was extrapolated to higher elevations by assuming a linear increase with elevation

. For the optimal

interpolation method the climatological spatial variation in precipitation was described by means of the standard

deviation, related to topographical features. Temperature was extrapolated using the wet adiabatic lapse rate. The

evaluation included comparison of areal estimates, verification against point observations and the water balance

equation and sensitivity analyses with respect to method parameters and network changes.

For operational runoff modelling in Sweden, areal precipitation and temperature have tradit

ionally been estimated by the

subjective weighting method. This evaluation showed that for routine applications this time-consuming method can be

replaced by optimal interpolation

. Inverse-distance weighting can not be recommended in areas with few stations and

complex gradients

.

The evaluation also showed that none of the methods correctly described the spatial variation in precipitation and

temperature in the investigated region. They are thus not directly applicable for non-routine modelling applications

where the estimation of runoff is not the sole objective. All methods also proved to be sensitive to at least some of the

necessary parameters like, e

.g., elevation dependency. This pointed to possible improvements of the estimates, as the

parameters for the evaluation were selected without special consideration to local conditions

. The optimal interpolation

method seemed to be the least sensitive to changes in the meteorological network.

Place, publisher, year, edition, pages
SMHI, 2000. p. 47
Series
RH, Report Hydrology, ISSN 0283-1104 ; 15
National Category
Oceanography, Hydrology and Water Resources
Research subject
Hydrology
Identifiers
urn:nbn:se:smhi:diva-2682 (URN)Hydrologi, Rapporter, Serie RH (Local ID)Hydrologi, Rapporter, Serie RH (Archive number)Hydrologi, Rapporter, Serie RH (OAI)
Available from: 2000-09-17 Created: 2016-07-08 Last updated: 2018-07-10Bibliographically approved
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