Climate change impact assessment on hydrological fluxes based on ensemble GCM outputs: a case study in eastern Indian River Basin

Abstract The present study assessed the impact of climate change in the Anandapur catchment of Baitarani River basin, India, using the Soil and Water Assessment Tool (SWAT) hydrological model. The future climatic alterations under two Representative Concentration Pathways (RCPs), i.e. 4.5 and 8.5 scenarios, are quantified by an ensemble of two different CMIP5 models, i.e. CNRM-CM5.0, GFDL-CM3.0. The outcomes of this study reveal that the future rainfall and temperature may experience an increasing trend with gradual shifting of monsoon from mid-June to mid-May. The average annual streamflow experienced the highest increase during the period 2071–2095, whereas the highest average annual evapotranspiration (ET) is observed for the period 2046–2070 under both the RCPs and resulting in comparatively slower groundwater recharge (GWR) over the basin. In order to implement suitable adaptation strategies for a possible flood scenario on the concerned study basin, three critical sub-basins, namely, sub-basin 1, 4, and 5, were identified. Furthermore, the altered streamflow and ET dynamics may result in a significant shifting in the conventional agricultural practice in the coming future time scales. Conclusively, the outcomes of this study have potential implications for policy makers in formulating the policies related to sustainable water resources management in future scenarios.

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Application of SWAT in Hydrological Simulation of Complex Mountainous River Basin (Part II: Climate Change Impact Assessment)

Water ◽

10.3390/w13111548 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1548

Author(s):

Suresh Marahatta ◽

Deepak Aryal ◽

Laxmi Prasad Devkota ◽

Utsav Bhattarai ◽

Dibesh Shrestha

Keyword(s):

Climate Change ◽

River Basin ◽

Climate Models ◽

Assessment Tool ◽

Swat Model ◽

Global Climate Models ◽

Climate Data ◽

The Future ◽

The Impact ◽

Mountainous River

This study aims at analysing the impact of climate change (CC) on the river hydrology of a complex mountainous river basin—the Budhigandaki River Basin (BRB)—using the Soil and Water Assessment Tool (SWAT) hydrological model that was calibrated and validated in Part I of this research. A relatively new approach of selecting global climate models (GCMs) for each of the two selected RCPs, 4.5 (stabilization scenario) and 8.5 (high emission scenario), representing four extreme cases (warm-wet, cold-wet, warm-dry, and cold-dry conditions), was applied. Future climate data was bias corrected using a quantile mapping method. The bias-corrected GCM data were forced into the SWAT model one at a time to simulate the future flows of BRB for three 30-year time windows: Immediate Future (2021–2050), Mid Future (2046–2075), and Far Future (2070–2099). The projected flows were compared with the corresponding monthly, seasonal, annual, and fractional differences of extreme flows of the simulated baseline period (1983–2012). The results showed that future long-term average annual flows are expected to increase in all climatic conditions for both RCPs compared to the baseline. The range of predicted changes in future monthly, seasonal, and annual flows shows high uncertainty. The comparative frequency analysis of the annual one-day-maximum and -minimum flows shows increased high flows and decreased low flows in the future. These results imply the necessity for design modifications in hydraulic structures as well as the preference of storage over run-of-river water resources development projects in the study basin from the perspective of climate resilience.

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Variations of Drought Tendency, Frequency, and Characteristics and Their Responses to Climate Change under CMIP5 RCP Scenarios in Huai River Basin, China

Water ◽

10.3390/w11102174 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2174 ◽

Cited By ~ 4

Author(s):

Jingcai Wang ◽

Hui Lin ◽

Jinbai Huang ◽

Chenjuan Jiang ◽

Yangyang Xie ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Eastern China ◽

Cmip5 Models ◽

Drought Severity ◽

Global Circulation Models ◽

Huai River Basin ◽

Huai River ◽

The Future ◽

The Impact

Huai River Basin (HRB) is an important food and industrial production area and a frequently drought-affected basin in eastern China. It is necessary to consider the future drought development for reducing the impact of drought disasters. Three global circulation models (GCMs) from Coupled Model Intercomparison Project phase 5 (CMIP5), such as CNRM-CM5 (CNR), HadGEM2-ES (Had) and MIROC5 (MIR), were used to assessment the future drought conditions under two Representative Concentration Pathways (RCPs) scenarios, namely, RCP4.5 and RCP8.5. The standardized precipitation evapotranspiration index (SPEI), statistical method, Mann-Kendall test, and run theory were carried out to study the variations of drought tendency, frequency, and characteristics and their responses to climate change. The research showed that the three CMIP5 models differ in describing the future seasonal and annual variations of precipitation and temperature in the basin and thus lead to the differences in describing drought trends, frequency, and drought characteristics, such as drought severity, drought duration, and drought intensity. However, the drought trend, frequency, and characteristics in the future are more serious than the history. The drought frequency and characteristics tend to be strengthened under the scenario of high concentration of RCP8.5, and the drought trend is larger than that of low concentration of RCP4.5. The lower precipitation and the higher temperature are the main factors affecting the occurrence of drought. All three CMIP5 models show that precipitation would increase in the future, but it could not offset the evapotranspiration loss caused by significant temperature rise. The serious risk of drought in the future is still higher. Considering the uncertainty of climate models for simulation and prediction, attention should be paid to distinguish the effects of different models in the future drought assessment.

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An evaluation of the effect of future climate on runoff in the Dongjiang River basin, South China

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-368-257-2015 ◽

2015 ◽

Vol 368 ◽

pp. 257-262

Author(s):

K. Lin ◽

W. Zhai ◽

S. Huang ◽

Z. Liu

Keyword(s):

Climate Change ◽

River Basin ◽

South China ◽

Annual Runoff ◽

Future Climate ◽

Weather Data ◽

Future Climate Change ◽

Dongjiang River ◽

The Future ◽

The Impact

Abstract. The impact of future climate change on the runoff for the Dongjiang River basin, South China, has been investigated with the Soil and Water Assessment Tool (SWAT). First, the SWAT model was applied in the three sub-basins of the Dongjiang River basin, and calibrated for the period of 1970–1975, and validated for the period of 1976–1985. Then the hydrological response under climate change and land use scenario in the next 40 years (2011–2050) was studied. The future weather data was generated by using the weather generators of SWAT, based on the trend of the observed data series (1966–2005). The results showed that under the future climate change and LUCC scenario, the annual runoff of the three sub-basins all decreased. Its impacts on annual runoff were –6.87%, –6.54%, and –18.16% for the Shuntian, Lantang, and Yuecheng sub-basins respectively, compared with the baseline period 1966–2005. The results of this study could be a reference for regional water resources management since Dongjiang River provides crucial water supplies to Guangdong Province and the District of Hong Kong in China.

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Representation of the Angolan low and Southern African Summer Precipitation in the CORDEX and CMIP5 models.

10.5194/egusphere-egu21-12531 ◽

2021 ◽

Author(s):

Sabina Abba-Omar ◽

Francesca Raffaele ◽

Erika Coppola ◽

Daniela Jacob ◽

Claas Teichmann ◽

...

Keyword(s):

Climate Change ◽

Regression Analysis ◽

Southern Africa ◽

Summer Precipitation ◽

Precipitation Variability ◽

Cmip5 Models ◽

Impact Of Climate Change ◽

The Future ◽

Rainfall Patterns ◽

The Impact

The impact of climate change on precipitation over Southern Africa is of particular interest due to its possible devastating societal impacts. To add to this, simulating precipitation is challenging and models tend to show strong biases over this region, especially during the Austral Summer (DJF) months. One of the reasons for this is the mis-representation of the Angolan Low (AL) and its influence on Southern Africa&#8217;s Summer precipitation in the models. Therefore, this study aims to explore and compare different models&#8217; ability to capture the AL and its link to precipitation variability as well as consider the impact climate change may have on this link. We also explore how the interaction between ENSO, another important mode of variability for precipitation, and the Angolan Low, impact precipitation, how the models simulate this and whether this could change in the future under climate change.&#160;We computed the position and strength of the AL in reanalysis data and compared these results to three different model ensembles with varying resolutions. Namely, the CORDEX-CORE ensemble (CCORE), a new phase of CORDEX simulations with higher resolutions (0.22 degrees), the lower resolution (0.44 degrees) CORDEX-phase 1 ensemble (C44) and the CMIP5 models that drive the two RCM ensembles. We also used Self Organizing Maps to group DJF yearly anomaly patterns and identify which combination of ENSO and AL strength scenarios are responsible for particularly wet or dry conditions. Regression analysis was performed to analyze the relationships between precipitation and the AL and ENSO. This analysis was repeated for near (2041-2060) and far (2080-2099) future climate and compared with the present to understand how the strength of the AL, and its connection to precipitation variability and ENSO, changes in the future.&#160;We found that, in line with previous studies, models with stronger AL tend to produce more rainfall. CCORE tends to simulate a stronger AL than C44 and therefore, higher precipitation biases. However, the regression analysis shows us that CCORE is able to capture the relationship between precipitation and the AL strength variability as well as ENSO better than the other ensembles. We found that generally dry rainfall patterns over Southern Africa are associated with a weak AL and El Nino event whereas wet rainfall patterns occur during a strong AL and La Nina year. While the models are able to capture this, they also tend to show more neutral ENSO conditions associated with these wet and dry patterns which possibly indicates less of a connection between AL strength and ENSO than seen in the observed results. Analysis of the future results indicates that the AL weakens, this is shown across all the ensembles and could be a contributing factor to some of the drying seen. These results have applications in understanding and improving model representation of precipitation over Southern Africa as well as providing some insight into the impact of climate change on precipitation and some of its associated dynamics over this region.

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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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Urban water demand assessment for sustainable water resources management, under climate change and socioeconomic changes

Water Science & Technology Water Supply ◽

10.2166/ws.2019.199 ◽

2019 ◽

Vol 20 (2) ◽

pp. 679-687 ◽

Cited By ~ 2

Author(s):

Angelos Alamanos ◽

Stamatis Sfyris ◽

Chrysostomos Fafoutis ◽

Nikitas Mylopoulos

Keyword(s):

Climate Change ◽

Water Management ◽

Water Resources ◽

Water Conservation ◽

Water Demand ◽

Management Scenarios ◽

Sustainable Water Resources Management ◽

The Future ◽

The Impact ◽

The City

Abstract The relationship between water abstraction and water availability has turned into a major stress factor in the urban exploitation of water resources. The situation is expected to be sharpened in the future due to the intensity of extreme meteorological phenomena, and socio-economic changes affecting water demand. In the city of Volos, Greece, the number of water counters has been tripled during the last four decades. This study attempts to simulate the city's network, supply system and water demand through a forecasting model. The forecast was examined under several situations, based on climate change and socio-economic observations of the city, using meteorological, water pricing, users' income, level of education, family members, floor and residence size variables. The most interesting outputs are: (a) the impact of each variable in the water consumption and (b) water balance under four management scenarios, indicating the future water management conditions of the broader area, including demand and supply management. The results proved that rational water management can lead to remarkable water conservation. The simulation of real scenarios and future situations in the city's water demand and balance, is the innovative element of the study, making it capable of supporting the local water utility.

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Simulation of the impact of climate change on runoff and drought in an arid and semiarid basin (the Hablehroud, Iran)

Applied Water Science ◽

10.1007/s13201-021-01494-2 ◽

2021 ◽

Vol 11 (10) ◽

Author(s):

Morteza Lotfirad ◽

Arash Adib ◽

Jaber Salehpoor ◽

Afshin Ashrafzadeh ◽

Ozgur Kisi

Keyword(s):

Climate Change ◽

River Basin ◽

Baseline Period ◽

Hydrological Drought ◽

Downward Trend ◽

Future Period ◽

Impact Of Climate Change ◽

The Future ◽

Rcp 8.5 ◽

The Impact

AbstractThis study evaluates the impact of climate change (CC) on runoff and hydrological drought trends in the Hablehroud river basin in central Iran. We used a daily time series of minimum temperature (Tmin), maximum temperature (Tmax), and precipitation (PCP) for the baseline period (1982–2005) analysis. For future projections, we used the output of 23 CMIP5 GCMs and two scenarios, RCP 4.5 and RCP 8.5; then, PCP, Tmin, and Tmax were projected in the future period (2025–2048). The GCMs were weighed based on the K-nearest neighbors algorithm. The results indicated a rising temperature in all months and increasing PCP in most months throughout the Hablehroud river basin's areas for the future period. The highest increase in the Tmin and Tmax in the south of the river basin under the RCP 8.5 scenario, respectively, was 1.87 °C and 1.80 °C. Furthermore, the highest reduction in the PCP was 54.88% in August under the RCP 4.5 scenario. The river flow was simulated by the IHACRES rainfall-runoff model. The annual runoff under the scenarios RCP 4.5 and RCP 8.5 declined by 11.44% and 13.13%, respectively. The basin runoff had a downward trend at the baseline period; however, it will have a downward trend in the RCP 4.5 scenario and an upward trend in the RCP 8.5 scenario for the future period. This study also analyzed drought by calculating the streamflow drought index for different time scales. Overall, the Hablehroud river basin will face short-term and medium-term hydrological drought in the future period.

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Drought occurrence under future climate change scenarios in the Zard River basin, Iran

Water Science & Technology Water Supply ◽

10.2166/ws.2020.367 ◽

2020 ◽

Author(s):

Pedram Mahdavi ◽

Hossein Ghorbanizadeh Kharazi ◽

Hossein Eslami ◽

Narges Zohrabi ◽

Majid Razaz

Keyword(s):

Climate Change ◽

River Basin ◽

Hydrological Drought ◽

Future Climate ◽

Future Climate Change ◽

Climate Change Scenarios ◽

Future Period ◽

Drought Assessment ◽

The Future ◽

The Impact

Abstract Global warming affected by human activities causes changes in the regime of rivers. Rivers are one of the most vital sources that supply fresh water. Therefore, management, planning, and proper use of rivers will be crucial for future climate change conditions. This study investigated the monitoring of hydrological drought in a future period to examine the impact of climate change on the discharging flow of the Zard River basin in Iran. Zard River is an important supplier of fresh and agricultural water in a vast area of Khuzestan province in Iran. A continuous rainfall-runoff model based on Soil Moisture Accounting (SMA) algorithm was applied to simulate the discharge flow under 10 scenarios (obtained from LARS-WG.6 software) of future climate change. Then, the Stream-flow Drought Index (SDI) and the Standard Precipitation Index (SPI) were calculated for each climate change scenario for the future period (2041–2060). The results of the meteorological drought assessment showed that near normal and moderate droughts had higher proportions among other drought conditions. Moreover, the hydrological drought assessment showed the occurrence of two new droughts (severe and extreme) conditions for the future period (2041–2060) that has never happened in the past (1997–2016).

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Assessment of Climate Change Impact on the Hydrology of the Kabul River Basin, Afghanistan

Journal of Water Engineering and Management ◽

10.47884/jweam.v2i1pp01-21 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Massouda Sidiqi ◽

Sangam Shrestha

Keyword(s):

Climate Change ◽

River Basin ◽

General Circulation ◽

Arid Regions ◽

Hydrological Cycle ◽

Mean Annual Temperature ◽

The Future ◽

The Impact ◽

Semi Arid ◽

Kabul River

Climate change and variability affect the availability and management of water resources and the hydrological cycle, especially in arid and semi-arid regions. This research was conducted to analyse the impact of climate change on the hydrology of the Kabul River Basin, Afghanistan by using the outputs of three General Circulation Models under two representative concentration pathway scenarios: RCP 4.5 and RCP 8.5. Future climate data (precipitation and temperature) obtained from the climate models were bias-corrected using the delta change approach. Maximum and minimum temperature and precipitation were predicted for the three future periods: 2020s (2010–2039), 2050s (2040–2069), and 2080s (2070–2099) against the baseline period 1961–1980. The o o o mean annual temperature in the basin is projected to increase by 1.8 C, 3.5 C, and 4.8 C in the 2020s, 2050s, and 2080s, respectively. The projected annual precipitation is expected to decline by approximately 53 to 65% for the whole river basin under both scenarios in the future period. The well-calibrated and validated Soil Water Assessment Tool (SWAT) was used to simulate the future streamflow in the basin. The mean annual streamflow is projected to increase by 50 to 120% in the future. This study provides valuable information for guiding future water resource management in the Kabul River Basin and other arid and semi-arid regions of Afghanistan.

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Identifying the runoff variation in the Naryn River Basin under multiple climate and land-use change scenarios

Journal of Water and Climate Change ◽

10.2166/wcc.2021.422 ◽

2021 ◽

Author(s):

J. S. Wu ◽

Y. P. Li ◽

J. Sun ◽

P. P. Gao ◽

G. H. Huang ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

River Basin ◽

Land Use Changes ◽

Arable Land ◽

Low Flow ◽

Ensemble Prediction ◽

Runoff Variation ◽

The Future ◽

The Impact

Abstract A multiple scenario-based ensemble prediction (MSEP) method is developed for exploring the impacts of climate and land-use changes on runoff in the Naryn River Basin. MSEP incorporates multiple global climate models, Cellular Automata–Markov and Soil and Water Assessment Tool (SWAT) within a general framework. MSEP can simultaneously analyze the effects of climate and land-use changes on runoff, as well as provide multiple climate and land-use scenarios to reflect the associated uncertainties in runoff simulation and prediction. Totally 96 scenarios are considered to analyze the trend and range of future runoff. Ensemble prediction results reveal that (i) climate change plays a leading role in runoff variation; (ii) compared to the baseline values, peak flow would increase 36.6% and low flow would reduce 36.8% by the 2080s, which would result in flooding and drought risks in the future and (iii) every additional hectare of arable land would increase the water deficit by an average of 10.9 × 103 m3, implying that the arable land should be carefully expanded in the future. Results suggest that, to mitigate the impact of climate change, the rational control of arable land and the active promotion of irrigation efficiency are beneficial for water resources management and ecological environmental recovery.

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