Assessment of Historical and Future Water Availability in Himalayan Tamor River Basin Nepal Utilizing CMIP5 CNRM Climate Model Experiments

Abstract In this study, the assessment of water availability under climate changing environment has been done in the Himalayan Tamor River Basin, Nepal using physically based, spatially distributed, a continuous model 'Soil and Water Assessment Tool' (SWAT). The hydrological simulation and projection have been performed in the historical (1996-2007) and future times (e.g. 30s, 40s, 50s, 60s, 70s, 80s, 90s). The climate change impact assessment on the hydrology of Tamor river basin has been performed utilizing the CMIP5 CNRM climate model datasets (with RCP4.5 and RCP8.5). The model calibration and parameterization uncertainty evaluation in the simulated and projected flows were done in SWATCUP using SUFI2 algorithm. The results obtained from the model calibration (1996-2004) and validation (2005-2007) showed a reliable estimate of daily streamflow for calibration period (R2 = 0.85, NSE =0.85 and PBIAS=-2.5) and validation period (R2 =0.87, NSE =0.85 and PBIAS=-5.4). The average annual water yield at the main outlet of the basin is computed as 1511.13 mm, and the total annual quantity is recorded as 6.25 BCM. The average annual precipitation over the seleced river basin is projected to be increased in all scenarios. The stations at higher altitude show more temperature rise than those at a lower elevation and thus there would be minimal snowfall has been projected in the basin by 2100 AD under both scenarios (RCP4.5 and RCP8.5). It is expected that the flow pattern in the future would be similar to the baseline pattern under all scenarios. The baseflow will be dramatically increased in all scenarios, but the lowest flow month would be shifted from March to February. Since the base flow during lean months would be increased in future as projected by all scenarios, there would not be adverse impacts on higher percentile flows. This study would be useful for the assessment of the possibility of storage type or run-off-river type hydro-project in the basin in terms of water availability.

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Understanding the Impacts of Climate Change in the Tana River Basin, Kenya

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-379-37-2018 ◽

2018 ◽

Vol 379 ◽

pp. 37-42 ◽

Cited By ~ 1

Author(s):

Lal Muthuwatta ◽

Aditya Sood ◽

Matthew McCartney ◽

Nishchitha Sandeepana Silva ◽

Alfred Opere

Keyword(s):

Climate Change ◽

Water Resources ◽

River Basin ◽

Assessment Tool ◽

Swat Model ◽

Baseline Period ◽

Base Flow ◽

Water Yield ◽

Hydrological Characteristics ◽

Tana River

Abstract. In the Tana River Basin in Kenya, six Regional Circulation Models (RCMs) simulating two Representative Concentration Pathways (RCPs) (i.e., 4.5 and 8.5) were used as input to the Soil and Water Assessment Tool (SWAT) model to determine the possible implications for the hydrology and water resources of the basin. Four hydrological characteristics – water yield, groundwater recharge, base flow and flow regulation – were determined and mapped throughout the basin for three 30-year time periods: 2020–2049, 2040–2069 and 2070–2099. Results were compared with a baseline period, 1983–2011. All four hydrological characteristics show steady increases under both RCPs for the entire basin but with considerable spatial heterogeneity and greater increases under RCP 8.5 than RCP 4.5. The results have important implications for the way water resources in the basin are managed. It is imperative that water managers and policy makers take into account the additional challenges imposed by climate change in operating built infrastructure.

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Multi-site calibration and validation of SWAT with satellite-based evapotranspiration in a data-sparse catchment in southwestern Nigeria

Hydrology and Earth System Sciences ◽

10.5194/hess-23-1113-2019 ◽

2019 ◽

Vol 23 (2) ◽

pp. 1113-1144 ◽

Cited By ~ 12

Author(s):

Abolanle E. Odusanya ◽

Bano Mehdi ◽

Christoph Schürz ◽

Adebayo O. Oke ◽

Olufiropo S. Awokola ◽

...

Keyword(s):

Soil Moisture ◽

River Basin ◽

Model Calibration ◽

Hydrological Model ◽

Assessment Tool ◽

Potential Evapotranspiration ◽

Swat Model ◽

Water Balance Components ◽

Southwestern Nigeria ◽

Calibration And Validation

Abstract. The main objective of this study was to calibrate and validate the eco-hydrological model Soil and Water Assessment Tool (SWAT) with satellite-based actual evapotranspiration (AET) data from the Global Land Evaporation Amsterdam Model (GLEAM_v3.0a) and from the Moderate Resolution Imaging Spectroradiometer Global Evaporation (MOD16) for the Ogun River Basin (20 292 km2) located in southwestern Nigeria. Three potential evapotranspiration (PET) equations (Hargreaves, Priestley–Taylor and Penman–Monteith) were used for the SWAT simulation of AET. The reference simulations were the three AET variables simulated with SWAT before model calibration took place. The sequential uncertainty fitting technique (SUFI-2) was used for the SWAT model sensitivity analysis, calibration, validation and uncertainty analysis. The GLEAM_v3.0a and MOD16 products were subsequently used to calibrate the three SWAT-simulated AET variables, thereby obtaining six calibrations–validations at a monthly timescale. The model performance for the three SWAT model runs was evaluated for each of the 53 subbasins against the GLEAM_v3.0a and MOD16 products, which enabled the best model run with the highest-performing satellite-based AET product to be chosen. A verification of the simulated AET variable was carried out by (i) comparing the simulated AET of the calibrated model to GLEAM_v3.0b AET, which is a product that has different forcing data than the version of GLEAM used for the calibration, and (ii) assessing the long-term average annual and average monthly water balances at the outlet of the watershed. Overall, the SWAT model, composed of the Hargreaves PET equation and calibrated using the GLEAM_v3.0a data (GS1), performed well for the simulation of AET and provided a good level of confidence for using the SWAT model as a decision support tool. The 95 % uncertainty of the SWAT-simulated variable bracketed most of the satellite-based AET data in each subbasin. A validation of the simulated soil moisture dynamics for GS1 was carried out using satellite-retrieved soil moisture data, which revealed good agreement. The SWAT model (GS1) also captured the seasonal variability of the water balance components at the outlet of the watershed. This study demonstrated the potential to use remotely sensed evapotranspiration data for hydrological model calibration and validation in a sparsely gauged large river basin with reasonable accuracy. The novelty of the study is the use of these freely available satellite-derived AET datasets to effectively calibrate and validate an eco-hydrological model for a data-scarce catchment.

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Evaluation and Analysis of Grid Precipitation Fusion Products in Jinsha River Basin Based on China Meteorological Assimilation Datasets for the SWAT Model

Water ◽

10.3390/w11020253 ◽

2019 ◽

Vol 11 (2) ◽

pp. 253 ◽

Cited By ~ 9

Author(s):

Dandan Guo ◽

Hantao Wang ◽

Xiaoxiao Zhang ◽

Guodong Liu

Keyword(s):

Statistical Analysis ◽

River Basin ◽

Assessment Tool ◽

Swat Model ◽

Correlation Coefficients ◽

High Accuracy ◽

Jinsha River ◽

Hydrological Simulation ◽

Large Spatial Scale ◽

Satellite Precipitation

Highly accurate and high-quality precipitation products that can act as substitutes for ground precipitation observations have important significance for research development in the meteorology and hydrology of river basins. In this paper, statistical analysis methods were employed to quantitatively assess the usage accuracy of three precipitation products, China Meteorological Assimilation Driving Datasets for the Soil and Water Assessment Tool (SWAT) model (CMADS), next-generation Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG) and Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA), for the Jinsha River Basin, a region characterized by a large spatial scale and complex terrain. The results of statistical analysis show that the three kinds of data have relatively high accuracy on the average grid scale and the correlation coefficients are all greater than 0.8 (CMADS:0.86, IMERG:0.88 and TMPA:0.81). The performance in the average grid scale is superior than that in grid scale. (CMADS: 0.86(basin), 0.6 (grid); IMERG:0.88 (basin),0.71(grid); TMPA:0.81(basin),0.42(grid)). According to the results of hydrological applicability analysis based on SWAT model, the three kinds of data fail to obtain higher accuracy on hydrological simulation. CMADS performs best (NSE:0.55), followed by TMPA (NSE:0.50) and IMERG (NSE:0.45) in the last. On the whole, the three types of satellite precipitation data have high accuracy on statistical analysis and average accuracy on hydrological simulation in the Jinsha River Basin, which have certain hydrological application potential.

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Assessing the Uncertainties of Four Precipitation Products for Swat Modeling in Mekong River Basin

Remote Sensing ◽

10.3390/rs11030304 ◽

2019 ◽

Vol 11 (3) ◽

pp. 304 ◽

Cited By ~ 6

Author(s):

Xiongpeng Tang ◽

Jianyun Zhang ◽

Chao Gao ◽

Gebdang Ruben ◽

Guoqing Wang

Keyword(s):

River Basin ◽

Assessment Tool ◽

Model Performance ◽

Mekong River ◽

Distributed Hydrological Model ◽

Parameter Uncertainties ◽

Mekong River Basin ◽

Daily Streamflow ◽

Precipitation Estimates ◽

Better Than

Using hydrological simulation to evaluate the accuracy of satellite-based and reanalysis precipitation products always suffer from a large uncertainty. This study evaluates four widely used global precipitation products with high spatial and temporal resolutions [i.e., AgMERRA (AgMIP modern-Era Retrospective Analysis for Research and Applications), MSWEP (Multi-Source Weighted-Ensemble Precipitation), PERSIANN-CDR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record), and TMPA (Tropical Rainfall Measuring Mission 3B42 Version7)] against gauge observations with six statistical metrics over Mekong River Basin (MRB). Furthermore, the Soil and Water Assessment Tool (SWAT), a widely used semi-distributed hydrological model, is calibrated using different precipitation inputs. Both model performance and uncertainties of parameters and prediction have been quantified. The following findings were obtained: (1) The MSWEP and TMPA precipitation products have good accuracy with higher CC, POD, and lower ME and RMSE, and the AgMERRA precipitation estimates perform better than PERSIANN-CDR in this rank; and (2) out of the six different climate regions of MRB, all six metrics are worse than that in the whole MRB. The AgMERRA can better reproduce the occurrence and contributions at different precipitation densities, and the MSWEP has the best performance in Cwb, Cwa, Aw, and Am regions that belong to the low latitudes. (3) Daily streamflow predictions obtained using MSWEP precipitation estimates are better than those simulated by other three products in term of both the model performance and parameter uncertainties; and (4) although MSWEP better captures the precipitation at different intensities in different climatic regions, the performance can still be improved, especially in the regions with higher altitude.

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Simulating the Impact of Climate Change on the Hydrological Regimes of a Sparsely Gauged Mountainous Basin, Northern Pakistan

Water ◽

10.3390/w11102141 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2141 ◽

Cited By ~ 4

Author(s):

Saddique ◽

Usman ◽

Bernhofer

Keyword(s):

Climate Change ◽

River Basin ◽

Assessment Tool ◽

High Elevation ◽

Climate Simulation ◽

Water Yield ◽

Research Station ◽

Impact Of Climate Change ◽

Global Circulation Models ◽

The Impact

Projected climate changes for the 21st century may cause great uncertainties on the hydrology of a river basin. This study explored the impacts of climate change on the water balance and hydrological regime of the Jhelum River Basin using the Soil and Water Assessment Tool (SWAT). Two downscaling methods (SDSM, Statistical Downscaling Model and LARS-WG, Long Ashton Research Station Weather Generator), three Global Circulation Models (GCMs), and two representative concentration pathways (RCP4.5 and RCP8.5) for three future periods (2030s, 2050s, and 2090s) were used to assess the climate change impacts on flow regimes. The results exhibited that both downscaling methods suggested an increase in annual streamflow over the river basin. There is generally an increasing trend of winter and autumn discharge, whereas it is complicated for summer and spring to conclude if the trend is increasing or decreasing depending on the downscaling methods. Therefore, the uncertainty associated with the downscaling of climate simulation needs to consider, for the best estimate, the impact of climate change, with its uncertainty, on a particular basin. The study also resulted that water yield and evapotranspiration in the eastern part of the basin (sub-basins at high elevation) would be most affected by climate change. The outcomes of this study would be useful for providing guidance in water management and planning for the river basin under climate change.

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Study on Hydrological Simulation of Jin River Based on SWAT-X Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.84-85.238 ◽

2011 ◽

Vol 84-85 ◽

pp. 238-243

Author(s):

Yu Jie Fang ◽

Wen Bin Zhou ◽

Ding Gui Luo

Keyword(s):

River Basin ◽

Assessment Tool ◽

Swat Model ◽

Model Parameters ◽

Parameter Sensitivity Analysis ◽

Hydrological Simulation ◽

Resources Management ◽

Using Data ◽

Sensitive Parameters ◽

Water Assessment

Hydrological simulation is the basis of water resources management and utilization. In this study, Soil and Water Assessment Tool (SWAT) model was applied to Jin River Basin for hydrological simulation on ArcView3.3 platform. The basic database of Jin river Basin was built using ArcGis9.2. Based on the LH-OAT parameter sensitivity analysis, the sensitive parameters of runoff were identified, including CN2, Gwqmn, rchrg_dp, ESCO, sol_z, SLOPE, SOL_AWC, sol_k, Gwrevap, and then model parameters related to runoff were calibrated and validated using data observed in weifang, yifeng, shanggao and gaoan hydrological stations during 2001-2008. The simulation showed that the simulated values were reasonably comparable to the observed data (Re<20%, R2 >0.7 and Nash-suttcliffe > 0.7), suggesting the validity of SWAT model in Jin River Basin.

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Performance of HEC-HMS and SWAT to simulate streamflow in the sub-humid tropical Hemavathi catchment

Journal of Water and Climate Change ◽

10.2166/wcc.2021.072 ◽

2021 ◽

Author(s):

N. C. Sanjay Shekar ◽

D. C. Vinay

Keyword(s):

Model Calibration ◽

Assessment Tool ◽

Swat Model ◽

Model Performance ◽

Curve Number ◽

Coefficient Of Determination ◽

Hydrological Models ◽

Daily Streamflow ◽

Compensation Factor ◽

Elevation Model

Abstract The present study was conducted to examine the accuracy and applicability of the hydrological models Soil and Water Assessment Tool (SWAT) and Hydrologic Engineering Center (HEC)- Hydrologic Modeling System (HMS) to simulate streamflows. Models combined with the ArcGIS interface have been used for hydrological study in the humid tropical Hemavathi catchment (5,427 square kilometer). The critical focus of the streamflow analysis was to determine the efficiency of the models when the models were calibrated and optimized using observed flows in the simulation of streamflows. Daily weather gauge stations data were used as inputs for the models from 2014–2020 period. Other data inputs required to run the models included land use/land cover (LU/LC) classes resulting from remote sensing satellite imagery, soil map and digital elevation model (DEM). For evaluating the model performance and calibration, daily stream discharge from the catchment outlet data were used. For the SWAT model calibration, available water holding capacity by soil (SOL_AWC), curve number (CN) and soil evaporation compensation factor (ESCO) are identified as the sensitive parameters. Initial abstraction (Ia) and lag time (Tlag) are the significant parameters identified for the HEC-HMS model calibration. The models were subsequently adjusted by autocalibration for 2014–2017 to minimize the variations in simulated and observed streamflow values at the catchment outlet (Akkihebbal). The hydrological models were validated for the 2018–2020 period by using the calibrated models. For evaluating the simulating daily streamflows during calibration and validation phases, performances of the models were conducted by using the Nash-Sutcliffe model efficiency (NSE) and coefficient of determination (R2). The SWAT model yielded high R2 and NSE values of 0.85 and 0.82 for daily streamflow comparisons for the catchment outlet at the validation time, suggesting that the SWAT model showed relatively good results than the HEC-HMS model. Also, under modified LU/LC and ungauged streamflow conditions, the calibrated models can be later used to simulate streamflows for future predictions. Overall, the SWAT model seems to have done well in streamflow analysis capably for hydrological studies.

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Hydrologic modeling of a Himalayan mountain basin by using the SWAT mode

10.5194/hess-2017-100 ◽

2017 ◽

Cited By ~ 3

Author(s):

Sharad K. Jain ◽

Sanjay K. Jain ◽

Neha Jain ◽

Chong-Yu Xu

Keyword(s):

Assessment Tool ◽

Swat Model ◽

Large Population ◽

Water Yield ◽

Model Parameters ◽

Hydrologic Response ◽

Water Balance Components ◽

Daily Streamflow ◽

Hydropower Potential ◽

Himalayan Mountain

Abstract. A large population depends on runoff from Himalayan rivers which have high hydropower potential; floods in these rivers are also frequent. Current understanding of hydrologic response mechanism of these rivers and impact of climate change is inadequate due to limited studies. This paper presents results of modeling to understand the hydrologic response and compute the water balance components of a Himalayan river basin in India viz. Ganga up to Devprayag. Soil and Water Assessment Tool (SWAT) model was applied for simulation of the snow/rainfed catchment. SWAT was calibrated with daily streamflow data for 1992–98 and validated with data for 1999–2005. Manual calibration was carried out to determine model parameters and quantify uncertainty. Results indicate good simulation of streamflow; main contribution to water yield is from lateral and ground water flow. Water yield and ET for the catchments varies between 43–46 % and 57–58 % of precipitation, respectively. The contribution of snowmelt to lateral runoff for Ganga River ranged between 13–20 %. More attention is needed to strengthen spatial and temporal hydrometeorological database for the study basins for improved modeling.

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Water availability, water demand, and reliability of in situ water harvesting in smallholder rain-fed agriculture in the Thukela River Basin, South Africa

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-6-4919-2009 ◽

2009 ◽

Vol 6 (4) ◽

pp. 4919-4959 ◽

Cited By ~ 2

Author(s):

J. C. M. Andersson ◽

A. J. B. Zehnder ◽

G. P. W. Jewitt ◽

H. Yang

Keyword(s):

South Africa ◽

River Basin ◽

Water Availability ◽

Assessment Tool ◽

Water Productivity ◽

Water Harvesting ◽

Crop Water ◽

Water Demands ◽

Crop Water Productivity

Abstract. Water productivity in smallholder rain-fed agriculture is of key interest for food and livelihood security. A frequently advocated approach to enhance water productivity is to adopt water harvesting and conservation technologies (WH). This study estimates water availability for in situ WH and supplemental water demands (SWD) in smallholder agriculture in the Thukela River Basin, South Africa. It incorporates process dynamics governing runoff generation and crop water demands, an explicit account of the reliability of in situ WH, and uncertainty considerations. The agro-hydrological model SWAT (Soil and Water Assessment Tool) was calibrated and evaluated with the SUFI-2 algorithm against observed crop yield and discharge in the basin. The water availability was based on the generated surface runoff in smallholder areas. The SWD was derived from a scenario where crop water deficits were met from an unlimited external water source. The reliability was calculated as the percentage of years in which the water availability ≥ the SWD. It reflects the risks of failure induced by the temporal variability in these factors. The results show that the smallholder crop water productivity is low in the basin (spatiotemporal median: 0.08–0.22 kg m−3, 95% prediction uncertainty band (95PPU). Water is available for in situ WH (spatiotemporal median: 0–17 mm year−1, 95PPU) which may aid in enhancing the crop water productivity by meeting some of the SWD (spatiotemporal median: 0–113 mm year−1, 95PPU). However, the reliability of in situ WH is highly location specific and overall rather low. Of the 1850 km2 of smallholder lands, 20–28% display a reliability ≥25%, 13–16% a reliability ≥50%, and 4–5% a reliability ≥75% (95PPU). This suggests that the risk of failure of in situ WH is relatively high in many areas of the basin.

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Projection of hydro-climatological changes over eastern Himalayan catchment by the evaluation of RegCM4 RCM and CMIP5 GCM models

Hydrology Research ◽

10.2166/nh.2017.193 ◽

2017 ◽

Vol 50 (1) ◽

pp. 117-137 ◽

Cited By ~ 10

Author(s):

Vishal Singh ◽

Ashutosh Sharma ◽

Manish Kumar Goyal

Keyword(s):

Climate Models ◽

Climate Model ◽

Assessment Tool ◽

Global Climate ◽

Phase 1 ◽

Swat Model ◽

Global Climate Models ◽

Eastern Himalaya ◽

Water Yield ◽

Temperature And Precipitation

Abstract Here, a regional climate model (RCM) RegCM4 and Coupled Model Intercomparison Project phase 5 (CMIP5) global climate models (GCMs) such as Coupled Physical Model (CM3), Coupled Climate Model phase 1 (CM2P1) and Earth System Model (ESM-2M) with their representative concentration pathway (RCP) datasets were utilized in projecting hydro-climatological variables such as precipitation, temperature, and streamflow in Teesta River basin in north Sikkim, eastern Himalaya, India. For downscaling, a ‘predictor selection analysis’ was performed utilizing a statistical downscaling model. The precision and applicability of RCM and GCM datasets were assessed using several statistical evaluation functions. The downscaled temperature and precipitation datasets were used in the Soil and Water Assessment Tool (SWAT) model for projecting the water yield and streamflow. A Sequential Uncertainty Parameter Fitting 2 optimization algorithm was used for optimizing the coefficient parameter values. The Mann–Kendall test results showed increasing trend in projected temperature and precipitation for future time. A significant increase in minimum temperature was found for the projected scenarios. The SWAT model-based projected outcomes showed a substantial increase in the streamflow and water yield. The results provide an understanding about the hydro-climatological data uncertainties and future changes associated with hydrological components that could be expected because of climate change.

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