Hydrologiska Byrans Vattenbalansavdelning Model Research Articles

Modelling Estimation of the Available Rainwater Resource in Gbédji-Kotovi Clay Area for Supplying Dikes and Dams

Floods and flows data are useful for dimensioning of dikes and dams which often include evacuation devices that regulate flows to ensure the volumes of water. The objective of this study is to estimate the available water resource in the village of Gbédji-Kotovi, located in the watershed of Couffo river in Benin by using sequentially, the HBV (Hydrologiska Byrans Vattenbalansavdelning) and GR4J (Rural Engineering model with 4 daily parameters) climate models. Hydrographs of water levels are simulated according to the calibration period (1994-1999) different from the validation one (1982-1988). Considering the Nash-Sutcliffe model Efficiency coefficient (NSE), the performance of GR4J model during calibration is slightly higher than the performance of the HBV model, while during the validation, the contrary is noticed. The annual rainfall average simulated is 1117.7 mm/year while the average observed is 1104.6 mm/year over the period 1981-2005. By 2050, on one hand, the annual flow rate values will vary from -19.2 to -11.9%, while the actual evapotranspiration will vary between 0.5 and -5.8; on another hand, the potential evapotranspiration and the annual precipitation remain constant. An average flow of 187 millions m3/year for annual average water depth of 1094 mm is obtained at Lanta rain station, which covers an area of 1664.47 km2, while this flow enabled an average flow of 327.5 millons m3/year to be obtained at the virtual station of our study area of 2908.15 km2. The flow rates corresponding to the return periods of 10, 25 and 50 years vary from 5.51 to 12.67 m3/s at the outlet of the virtual station; while those at the outlet of Lanta station vary from 3.6 to 6.6 m3/s. However, the simulated water quantiles cannot be fully mobilized; because of the uses, they undergo upstream and downstream. Thus, Gbédji-Kotovi locality requires the implementation of an integrated water resource management strategy that includes the construction of dikes and dams.

Impact of climate change on surface water availability and crop water demand for the sub-watershed of Abbay Basin, Ethiopia

In the present study, climate change effects on surface water availability and crop water demand (CWD) were evaluated in the Birr watershed (a sub-watershed of Abbay Basin), Ethiopia. The Coordinated Regional Climate Downscaling Experiment (CORDEX)-Africa data output of Hadley Global Environment Model 2-Earth System (HadGEM2-ES) was selected under the representative concentration pathways (RCP) scenarios. The seasonal and annual streamflow trends in the watershed were assessed using the Mann–Kendall (MK) test and Sen’s slope at 5% significance level. The surface water availability was assessed using the Hydrologiska Byrans Vattenbalansavdelning (HBV) model. The HBV model showed a satisfactory performance during calibration (R2 = 0.89) and validation (R2 = 0.85). The future water availability was simulated under climate change scenarios. The future projected streamflow indicates that minimum flow may decrease under RCP4.5 and RCP8.5 scenarios, revealing significant downward shifts in the years 2035 and 2055, respectively. Similarly, the 1 day and 7 days maximum flow under RCP8.5 and 90 days flow under RCP4.5 are expected to decrease significantly and a considerable shift may occur in the 2060s and 2030s, respectively. Contrarily, both the minimum and maximum flow may not change significantly under the RCP2.6 scenario. Current and future water demand for the maize crop was estimated using the CROPWAT. The result indicated that irrigation water requirement (IWR) for maize crop may be increased throughout the growing periods, especially, during the development stage. Therefore, this study may contribute to the planning and implementation of the sustainable water resources development strategies and help to mitigate the consequences of climatic change, especially on commonly grown crops in the region.

Determination of Extreme Hydrological Index using HBV Model Simulation Results (Case Study : Upper Ciliwung Watershed)

The study of climate change on hydrological response is a crucial as climate change impact will drive the change in hydrological regimes of river. Upper Ciliwung watershed is one of the critical rivers in Java Island, which has been affected by climate change. This study aims to: (i) simulate the discharge flow using the Hydrologiska Byrans Vattenbalansavdelning (HBV) model; (ii) simulate future flow using three general circulation models (GCM) namely Commonwealth Scientific and Industrial Research Organisation (CSIRO) Mk.3.6.0, Model for Interdisciplinary Research on Climate version 5 (MIROC5), and Geophysical Fluid Dynamics Laboratory-Coupled Model generation 3 (GFDL-CM3); (iii) determine the changes of extreme hydrological index during historical period (2001-2015) and projected period (2031-2045). The historical year simulation and projections are used to determine eight hydrologic extreme indices for high flow and low flow. We calibrated the HBV model for two years (2001-2002) and validated it for two years (2003-2004). Our model performed well in discharge simulation as shown by the NSE values (0.66 for calibration and validation). Then we calculated the indices for each period used (historical and projected). To show the changes in hydrological regimes, we compare the indices between two periods. Changes in the index of the two periods tend to decrease in value on the index parameters that characterize the minimum extreme events. Hence, that it is possible in the projected period there will be extreme hydrological events in the form of drought.

Actual Evapotranspiration in the High Andean Grasslands: A Comparison of Measurement and Estimation Methods

Actual evapotranspiration (ETa) explains the exchange of water and energy between soil, land surface and atmosphere. Despite its importance, it remains difficult to measure directly. Grasslands represent a widespread ecosystem for which further assessment of the measurement and estimation of ETa is needed. Thus, the objective of this study was to compare measurements and estimations of ETa in a mountain grassland ecosystem made using different approaches. The study was conducted in the Zhurucay Ecohydrological Observatory, located in the high Andes of Ecuador between 3500 and 3900 m a.s.l. The study area is a representative site of the paramo ecosystem, in which the vegetation mainly consists of tussock grasslands. ETa was measured or estimated using the following methods: eddy-covariance (EC), volumetric lysimeters (Lys), water balance (WB), energy balance (EB), the calibrated Penman-Monteith equation (PMCal), and two hydrological models (the Probability Distribution Model (PDM) and the Hydrologiska Byrans Vattenbalansavdelning model (HBV-light)). During one year, precipitation (P) accumulated to 1094 mm while ETa (measured with EC) accumulated to 622 mm (with ETa/P = 0.57). On a daily basis, the EC method measured average ETa rates of 1.7 mm/day. The best daily estimates according to percentage bias (pbias), normalized root mean square error (nRMSE), Pearson’s correlation coefficient (r) and the volumetric coefficient (ve) came from the HBV-light model, followed by the PMCal and the PDM (pbias: -2 to -20 %, nRMSE: 12–15 %, r: 0.7–0.9, and ve: 0.7–0.8). On the other hand, the WB, EB, and Lys estimates showed a poor performance (pbias: -10 to -19 %, nRMSE: 25–93 %, r: -0.4 to 0.5, and ve: -0.5 to 0.7). As the methods used in this study are of different types (hydrological, micrometeorological and analytical), their suitability and applications are discussed in terms of their costs, temporal resolution and accuracy. This study identifies low-cost and easy-to-implement alternatives to EC measurements, such as hydrological models and the calibrated Penman-Monteith equation. This study also allows us to provide an increment of progress on the accurate closure of the water balance in grasslands.

Use of canopy coefficients obtained from satellite data to estimate evapotranspiration over high mountain Mediterranean watersheds

<p><strong>Abstract.</strong> This work explores the dynamics of the water consumed by the vegetation in two Mediterranean watersheds of Sierra Nevada Mountains (Southern Spain). This region has experienced an increase in the demand of water in the last years due to the growth of irrigated areas, and a new water resources plan is required. The evapotranspiration (ET) of irrigated horticultural crops and natural communities were monitored for the hydrological years 2013/14 and 2014/15, using an approach based on the concept of reference evapotranspiration (ET<span class="inline-formula"><sub>o</sub></span>) and canopy coefficients derived from the computation of vegetation indices (VIs), which we will call the VI-ET<span class="inline-formula"><sub>o</sub></span> approach. A set of Landsat-8 and MODIS images has been used as remote input data. The results were used for the spatial analysis of water consumption in terms of the main land cover types in the area. The annual runoff obtained with a simple surface water balance, using the ET values estimated by the VI-ET<span class="inline-formula"><sub>o</sub></span> approach, was comparable to that obtained by the HBV (Hydrologiska Byrans Vattenbalansavdelning) model, a precipitation-runoff generation model that reproduces the observed river discharge at the outlet of the watershed.</p>

Assessment of future climate change impacts on hydrological behavior of Richmond River Catchment

This study evaluated the impacts of future climate change on the hydrological response of the Richmond River Catchment in New South Wales (NSW), Australia, using the conceptual rainfall-runoff modeling approach (the Hydrologiska Byrans Vattenbalansavdelning (HBV) model). Daily observations of rainfall, temperature, and streamflow and long-term monthly mean potential evapotranspiration from the meteorological and hydrological stations within the catchment for the period of 1972–2014 were used to run, calibrate, and validate the HBV model prior to the streamflow prediction. Future climate signals of rainfall and temperature were extracted from a multi-model ensemble of seven global climate models (GCMs) of the Coupled Model Intercomparison Project Phase 3 (CMIP3) with three regional climate scenarios, A2, A1B, and B1. The calibrated HBV model was then forced with the ensemble mean of the downscaled daily rainfall and temperature to simulate daily future runoff at the catchment outlet for the early part (2016–2043), middle part (2044–2071), and late part (2072–2099) of the 21st century. All scenarios during the future periods present decreasing tendencies in the annual mean streamflow ranging between 1% and 24.3% as compared with the observed period. For the maximum and minimum flows, all scenarios during the early, middle, and late parts of the century revealed significant declining tendencies in the annual mean maximum and minimum streamflows, ranging between 30% and 44.4% relative to the observed period. These findings can assist the water managers and the community of the Richmond River Catchment in managing the usage of future water resources in a more sustainable way.

A hydrological model modified for application to flood forecasting in medium and small-scale catchments

Steep headwater catchments in areas that experience intense rainfall can generate rapid floods. The significant risk to life and property posed by rapid floods means that they are a subject of great interest to flood forecasting. However, the rapid rise and short duration of flood hydrographs presents a difficulty for standard precipitation-runoff models, which generally operate on a daily time-step. The Hydrologiska Byrans Vattenbalansavdelning (HBV) model is a conceptual distributed hydrological model, normally applied to simulation of snow-melt hydrographs that can operate with an hourly time-step. In this paper, we modified the HBV model by adding a hillslope overland flow component so that the model would have more physical meaning when applied to prediction of floods humid climate zones. Hourly models for small-, medium-, and large-sized floods were calibrated and validated for flood events from the Tangjing catchment, a medium and small catchment within a humid subtropical climate zone of China. The calibration period utilized 50 events from the period 1980–1999, and the validation period utilized 20 flood events from the period 2000–2004. The model performance was evaluated using the Nash–Sutcliffe efficiency index and indicators of compliance of the modeled result with the observed result in terms of flood peak magnitude, flood runoff volume, and duration of flood peak. These indicators demonstrated good agreement between the observed and simulated hydrographs for the calibration and validation periods, achieving a reliability that was adequate for the purpose of flood forecasting in accordance with the relevant Chinese standard. We also applied the HBV model in its original configuration to the flood events, but its performance was generally inferior to that of the modified model. The modified model outperformed the original model mainly with respect to simulation of flood peak magnitude and flood peak timing.

Hydrological change detection using modeling: Half a century of runoff from four rivers in the Blue Nile Basin

[1] Land cover changes can have significant impacts on hydrological regime. The objective of this study was to detect possible hydrological changes of four watersheds in the Blue Nile Basin using a model-based method for hydrological change detection. The four watersheds, Birr, Upper-Didesa, Gilgel Abbay, and Koga range in size from 260 to 1800 km2. The changes were assessed based on model parameters, model residuals, and in the overall function of the watersheds in transferring rainfall into runoff. The entire time series (1960–2004) was divided into three periods based on political and land management policy changes. A conceptual rainfall-runoff model, the HBV (Hydrologiska Byrans Vattenbalansavdelning) model, was used for the analysis, and suitable parameter sets for each period were found based on a Monte Carlo approach. The values of six out of nine parameters changed significantly between the periods. Model residuals also showed significant changes between the three periods in three of the four watersheds. On the other hand, the overall functioning of the watersheds in processing rainfall to runoff changed little. So even though the individual parameters and model residuals were changing, the integrated functioning of the watersheds showed minimal changes. This study demonstrated the value of using different approaches for detecting hydrological change and highlighted the sensitivity of the outcome to the applied modeling and statistical methods.

Internal validation of conceptual rainfall–runoff models using baseflow separation

Summary An important tool in the management of floods is the use of rainfall–runoff models to predict the arrival of discharge peaks. These models generally use rainfall and potential evapotranspiration rates as input, and relate these to the catchment discharge through a number of conceptual equations. The parameters of these equations are estimated through a comparison of the modeled discharge to the observations. Only one variable, catchment discharge, is thus generally used to calibrate and validate these models. The objective of this paper is to validate the internal model dynamics of two widely used rainfall–runoff models using baseflow estimates. The baseflow time series used in this paper are obtained through the use of a physically-based digital baseflow filter. These models, the Hydrologiska Byrans Vattenbalansavdelning (HBV) model and the Probability Distributed Model (PDM), were calibrated using 1 year of hourly discharge data. The HBV model uses a linear reservoir for the modeling of groundwater flow, while the PDM uses a cubic reservoir for this purpose. In order to assess the impact of the type of reservoir choice, the cubic reservoir in the PDM was also replaced by a linear reservoir. Two different parameter estimation algorithms were used for model calibration. The Shuffled Complex Evolution (SCE-UA) algorithm minimizes the Root Mean Square Error between the model simulations and the observations, while Multistart Weight-Adaptive Recursive Parameter Estimation (MWARPE) uses the Extended Kalman Filter equations in an iterative, Monte-Carlo framework. MWARPE was found to lead to the best discharge simulations, but the differences with the results obtained from the SCE-UA algorithm were relatively small. When only the modeled discharge was analyzed, no clear picture emerged of which model produced the best results. However, it has been found that the replacement of the cubic groundwater reservoir in the PDM by a linear reservoir resulted in a strongly improved model performance with respect to the baseflow. Further, MWARPE consistently led to the best baseflow estimates for the three models, while the HBV model resulted in the best simulations of the baseflow, regardless of the calibration algorithm. The overall conclusion of this paper is that, even though it may be difficult to assess which model and calibration algorithm resulted in the best discharge estimates, the MWARPE calibration algorithm and the HBV model consistently led to the best internal model dynamics.

Correction to “Regularity‐based functional streamflow disaggregation: 2. Extended demonstration”

[1] In the paper ‘‘Regularity-based functional streamflow disaggregation: 2. Extended demonstration’’ by P. Carl et al. (Water Resources Research, 44, W03426, doi:10.1029/ 2006WR005056), there is an error in paragraph 5. The sentence ‘‘SWIM results are supplemented by an ad hoc Hydrological Bureau (HBV), Waterbalance Section [Bergstrom, 1995]’’ should read ‘‘SWIM results are supplemented by an ad hoc account using the HBV (Hydrologiska Byrans Vattenbalansavdelning, i.e., ‘‘Hydrological Bureau, Waterbalance Section’’) model [Bergstrom, 1995].’’ [2] The caption of Figure 24 should read as follows. [3] Figure 24. Daily streamflow analysis for 1992, in m/s, for Babelsberg (Nuthe). (top) HBV 1 total streamflow (g) and its FSD ilf (g‘), transient (gt), and fast (gf = g gt g‘) modes. (middle) HBV 1 total streamflow (g) and its base flow (gb), interflow (gi), and overland flow (gr = g gi gb); the dashed line represents observed total streamflow (g). (bottom) HBV 2 total streamflow (g) and its HBV components; the dash-dotted line represents ilf mode (g‘) of HBV 2 FSD analysis. [4] The caption of Figure 28 should read as follows. [5] Figure 28. Slow mode analysis of SWIM simulation during 1987–1989 in m/s for (top to bottom) Wechselburg, Babelsberg, and Gadow: FSD slow (gs) and ilf (g‘) components and SWIM base flow (gb); the dash-dotted (longdashed) line represents FSD ilf (slow) modes of observed data for comparison.