Impact of Climate Change on  River Flows in the Black Volta River

This paper assesses the impact of climate change in the Black Volta River by using data output from the atmospheric general circulation model with a 20-km resolution (AGCM20) through the Japanese Meteorological Agency (JMA) and the Meteorological Research Institute (MRI). The Black Volta, which flows mainly in Burkina Faso and Ghana in West Africa, is a major tributary of the Volta River. The basin covers 142,056 km2 and has a semi-arid tropical climate. Before applying AGCM20 output to a rainfall–runoff model, the performance of the AGCM20 rainfall data is investigated by comparing it with the observed rainfall in the Black Volta Basin. To assess the possible impact of rainfall change on river flow, a kinematic wave model, which takes into consideration saturated and unsaturated subsurface soil zones, was performed. The rainfall analysis shows that, the correlation coefficient of the monthly rainfall between the observed rainfall and AGCM20 for the present climate (1979–2004) is 0.977. In addition, the analysis shows that AGCM20 overestimates precipitation during the rainy season and underestimates the dry season for the present climate. The analysis of the AGCM20 output shows the precipitation pattern change in the future (2075–2099). In the future, precipitation is expected to increase by 3%, whereas evaporation and transpiration are expected to increase by 5% and by 8%, respectively. Also, daily maximum rainfall is expected to be 20 mm, or 60%, higher. Thus, the future climate in this region is expected to be more severe. The rainfall–runoff simulation is successfully calibrated at the Bamboi discharge gauging station in the Black Volta fromJune 2000 to December 2000 with 0.72 of the Nash–Sutcliffe model efficiency index. The model is applied with AGCM20 outputs for the present climate (1979–2004) and future climate (2075–2099). The results indicate that future discharge will decrease from January to July at the rate of the maximum of 50% and increase fromAugust to December at the rate of the maximumof 20% in the future. Therefore, comprehensive planning for both floods and droughts are urgently needed in this region.

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Effect of Climate Change on the Rainfall Trends: A case study of Pune, India

10.21203/rs.3.rs-1035885/v1 ◽

2021 ◽

Author(s):

Shalaka Shah ◽

Shreenivas Londhe

Keyword(s):

Climate Change ◽

General Circulation ◽

General Circulation Models ◽

Climate Data ◽

Maximum Rainfall ◽

Accurate Model ◽

Impact Of Climate Change ◽

The Future ◽

Grid Points ◽

The Impact

Abstract It is the need of the hour to predict the impact of climate change, especially rainfall on the future environmental conditions on local as well as global scales. The present work aims at studying the impact of climate change on the rainfall occurring over Pune, the eighth largest city in India. The General Circulation Models (GCMs) are predominantly used to obtain the climate data all over the globe, at various grid points, for past and future years. Rainfall values obtained from these grid points need to be downscaled to make them location specific. This study proposes a soft computing tool, Artificial Neural Network (ANN) for the purpose of downscaling. The rainfall data at 4 grid points surrounding Pune, was extracted from 5 different GCMs and given as input to ANN with observed rainfall as output, thus forming 5 models. For comparison, a pre-existing downscaling technique, Distribution based scaling (DBS) was used. The coefficient of correlation (r) showed that ANN was working better than DBS. The value of r for ANN was 0.73 for its least accurate model whereas DBS managed to reach 0.73 for its most accurate model. The future rainfall estimated with the help of the trained ANN models show an increase in mean rainfall over the Pune region by ∼2 – 15% and decrease in maximum rainfall by ∼40 – 65%. Peak prediction of rainfall simulated by ANN was not very accurate and hence there is still an opportunity for improvement which is the future scope of this study.

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Impact of climate change on ice regime in a river regulated for hydropower

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2014-0261 ◽

2015 ◽

Vol 42 (9) ◽

pp. 634-644 ◽

Cited By ~ 7

Author(s):

Netra P. Timalsina ◽

Knut T. Alfredsen ◽

Ånund Killingtveit

Keyword(s):

Climate Change ◽

General Circulation ◽

Model Simulation ◽

Regulated River ◽

River Ice ◽

Impact Of Climate Change ◽

The Future ◽

Ice Conditions ◽

Ice Regime ◽

The Impact

The ice conditions in a regulated river will depend on the climatic changes as well as the changes to the hydropower operation strategies in the future. The existing literature shows that very few studies have been carried out to investigate the impact of climate change on the river ice regime, which is important for operation of hydropower in cold climates. In this study, a series of modelling tools have been used to transform the climate change signal in terms of precipitation and air temperature into cross-section based river ice assessment in a basin with a complicated hydropower system. The study is based on the EURO-CORDEX climate change data extracted from a regional climate model driven by a suite of five general circulation models with three representative concentration pathways. Hydrological model simulation results show that the winter and spring flow will be increased, which will have an impact on the river ice conditions towards the middle and end of this century. Reservoir-hydropower model simulation shows that the production flows in the winter will be increased in the future. River ice model simulation shows the number of days with freezing water temperature are reduced in the future climate, and correspondingly days with frazil ice are reduced at most of the locations in the study area. The future period with ice cover will also be shortened. The paper also demonstrates a general methodology and procedure to simulate future ice conditions in a regulated river combining multiple models and data sets.

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Investigating the Impact of Climate Change on Future Runoff of River Satluj

Journal of Hydrology and Meteorology ◽

10.3126/jhm.v8i1.15568 ◽

2016 ◽

Vol 8 (1) ◽

pp. 10-21

Author(s):

Narayan P Gautam ◽

Manohar Arora ◽

N.K. Goel ◽

A.R.S. Kumar

Keyword(s):

Climate Change ◽

Water Resources ◽

General Circulation ◽

Circulation Model ◽

Climate Change Scenarios ◽

Impact Of Climate Change ◽

Basin Scale ◽

The Future ◽

Future Climatic Condition ◽

The Impact

Climate change has been emerging as one of the challenges in the global environment. Information of predicted climatic changes in basin scale is highly useful to know the future climatic condition in the basin that ultimately becomes helpful to carry out planning and management of the water resources available in the basin. Climatic scenario is a plausible and often simplified representation of the future climate, based on an internally consistent set of climatological relationships that has been constructed for explicit use in investigating the potential consequences of anthropogenic climate change. This study based on statistical downscaling, provide good example focusing on predicting the rainfall and runoff patterns, using the coarse general circulation model (GCM) outputs. The outputs of the GCMs are utilized to study the impact of climate change on water resources. The present study has been taken up to identify the climate change scenarios for Satluj river basin, India.Journal of Hydrology and Meteorology, Vol. 8(1) p.10-21

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Potential Climate Change Impacts on Water Resources in Egypt

Water ◽

10.3390/w13121715 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1715

Author(s):

Soha M. Mostafa ◽

Osama Wahed ◽

Walaa Y. El-Nashar ◽

Samia M. El-Marsafawy ◽

Martina Zeleňáková ◽

...

Keyword(s):

Climate Change ◽

Water Resources ◽

Irrigation Water ◽

General Circulation ◽

General Circulation Models ◽

Future Climate ◽

Future Climate Change ◽

Impact Of Climate Change ◽

Water Demands ◽

The Impact

This paper presents a comprehensive study to assess the impact of climate change on Egypt’s water resources, focusing on irrigation water for agricultural crops, considering that the agriculture sector is the largest consumer of water in Egypt. The study aims to estimate future climate conditions using general circulation models (GCMs), to assess the impact of climate change and temperature increase on water demands for irrigation using the CROPWAT 8 model, and to determine the suitable irrigation type to adapt with future climate change. A case study was selected in the Middle part of Egypt. The study area includes Giza, Bani-Sweif, Al-Fayoum, and Minya governorates. The irrigation water requirements for major crops under current weather conditions and future climatic changes were estimated. Under the conditions of the four selected models CCSM-30, GFDLCM20, GFDLCM21, and GISS-EH, as well as the chosen scenario of A1BAIM, climate model (MAGICC/ScenGen) was applied in 2050 and 2100 to estimate the potential rise in the annual mean temperature in Middle Egypt. The results of the MAGICC/SceGen model indicated that the potential rise in temperature in the study area will be 2.12 °C in 2050, and 3.96 °C in 2100. The percentage of increase in irrigation water demands for winter crops under study ranged from 6.1 to 7.3% in 2050, and from 11.7 to 13.2% in 2100. At the same time, the increase in irrigation water demands for summer crops ranged from 4.9 to 5.8% in 2050, and from 9.3 to 10.9% in 2100. For Nili crops, the increase ranged from 5.0 to 5.1% in 2050, and from 9.6 to 9.9% in 2100. The increase in water demands due to climate change will affect the water security in Egypt, as the available water resources are limited, and population growth is another challenge which requires a proper management of water resources.

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Impact of climate change on drought in the Daklak province

Science and Technology Development Journal ◽

10.32508/stdj.v17i3.1365 ◽

2014 ◽

Vol 17 (3) ◽

pp. 5-11

Author(s):

Khoi Nguyen Dao ◽

Quang Nguyen Xuan Chau

Keyword(s):

Climate Change ◽

General Circulation ◽

Standardized Precipitation Index ◽

Circulation Model ◽

Meteorological Drought ◽

Impact Of Climate Change ◽

The Future ◽

Delta Change ◽

The Standardized Precipitation Index ◽

The Impact

The main objective of this study was to evaluate the impact of climate change on the meteorological drought in the Daklak province. In this study, the meteorological drought was calculated using the Standardized Precipitation Index (SPI).From this result, two scensrios fot the precipitation VA1B and B1 were downscaled, from the outputs of 4 GCMs (General Circulation Model): CGCM3.1 (T63), CM2.0, CM2.1, and HadCM3 using the simple downscaling method (delta change method). The impacts of climate change on the droughts were assessed by comparing the present (1980- 2009) and the future droughts (2010-2039, 2040-2069, and 2070-2099).Results of the study suggested that the future temperature would increase by 0.9-2.8ºC and the future precipitation would decrease by 0.4-4.7% for both A1B and B1 scenarios. Under the future climate scenarios, the frequency and severity of extreme drought would increase. The results obtained in this study could be useful for planning and managing water resources at this region.

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Potential Impact of the Current and Future Climate on the Yield, Quality, and Climate Suitability for Tea [Camellia sinensis (L.) O. Kuntze]: A Systematic Review

Agronomy ◽

10.3390/agronomy11040619 ◽

2021 ◽

Vol 11 (4) ◽

pp. 619

Author(s):

Sadeeka Layomi Jayasinghe ◽

Lalit Kumar

Keyword(s):

Climate Change ◽

Future Climate ◽

Mitigation Strategies ◽

Extreme Weather Events ◽

Impact Of Climate Change ◽

Advantages And Disadvantages ◽

Tea Quality ◽

Climate Suitability ◽

Yield Quality ◽

The Impact

Even though climate change is having an increasing impact on tea plants, systematic reviews on the impact of climate change on the tea system are scarce. This review was undertaken to assess and synthesize the knowledge around the impacts of current and future climate on yield, quality, and climate suitability for tea; the historical roots and the most influential papers on the aforementioned topics; and the key adaptation and mitigation strategies that are practiced in tea fields. Our findings show that a large number of studies have focused on the impact of climate change on tea quality, followed by tea yield, while a smaller number of studies have concentrated on climate suitability. Three pronounced reference peaks found in Reference Publication Year Spectroscopy (RYPS) represent the most significant papers associated with the yield, quality, and climate suitability for tea. Tea yield increases with elevated CO2 levels, but this increment could be substantially affected by an increasing temperature. Other climatic factors are uneven rainfall, extreme weather events, and climate-driven abiotic stressors. An altered climate presents both advantages and disadvantages for tea quality due to the uncertainty of the concentrations of biochemicals in tea leaves. Climate change creates losses, gains, and shifts of climate suitability for tea habitats. Further studies are required in order to fill the knowledge gaps identified through the present review, such as an investigation of the interaction between the tea plant and multiple environmental factors that mimic real-world conditions and then studies on its impact on the tea system, as well as the design of ensemble modeling approaches to predict climate suitability for tea. Finally, we outline multifaceted and evidence-based adaptive and mitigation strategies that can be implemented in tea fields to alleviate the undesirable impacts of climate change.

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How will future climate depending agronomic management impact the yield risk of wheat cropping systems? A regional case study of Eastern Denmark

The Journal of Agricultural Science ◽

10.1017/s0021859620001045 ◽

2021 ◽

pp. 1-16

Author(s):

J. Macholdt ◽

J. Glerup Gyldengren ◽

E. Diamantopoulos ◽

M. E. Styczen

Keyword(s):

Climate Change ◽

Crop Production ◽

Cropping Systems ◽

Future Climate ◽

Catch Crops ◽

Agronomic Management ◽

The Future ◽

Yield Risk ◽

Management Factors ◽

The Impact

Abstract One of the major challenges in agriculture is how climate change influences crop production, for different environmental (soil type, topography, groundwater depth, etc.) and agronomic management conditions. Through systems modelling, this study aims to quantify the impact of future climate on yield risk of winter wheat for two common soil types of Eastern Denmark. The agro-ecosystem model DAISY was used to simulate arable, conventional cropping systems (CSs) and the study focused on the three main management factors: cropping sequence, usage of catch crops and cereal straw management. For the case region of Eastern Denmark, the future yield risk of wheat does not necessarily increase under climate change mainly due to lower water stress in the projections; rather, it depends on appropriate management and each CS design. Major management factors affecting the yield risk of wheat were N supply and the amount of organic material added during rotations. If a CS is characterized by straw removal and no catch crop within the rotation, an increased wheat yield risk must be expected in the future. In contrast, more favourable CSs, including catch crops and straw incorporation, maintain their capacity and result in a decreasing yield risk over time. Higher soil organic matter content, higher net nitrogen mineralization rate and higher soil organic nitrogen content were the main underlying causes for these positive effects. Furthermore, the simulation results showed better N recycling and reduced nitrate leaching for the more favourable CSs, which provide benefits for environment-friendly and sustainable crop production.

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A simulation study on the effect of climate change on crop water use and chill unit accumulation

South African Journal of Science ◽

10.17159/sajs.2017/20160119 ◽

2017 ◽

Vol 113 (7/8) ◽

Author(s):

Abiodun A. Ogundeji ◽

Henry Jordaan

Keyword(s):

Climate Change ◽

Water Resources ◽

Water Use ◽

Irrigation System ◽

Future Climate ◽

Crop Water ◽

Crop Water Use ◽

Chill Unit ◽

The Future ◽

The Impact

Climate change and its impact on already scarce water resources are of global importance, but even more so for water scarce countries. Apart from the effect of climate change on water supply, the chill unit requirement of deciduous fruit crops is also expected to be affected. Although research on crop water use has been undertaken, researchers have not taken the future climate into consideration. They also have focused on increasing temperatures but failed to relate temperature to chill unit accumulation, especially in South Africa. With a view of helping farmers to adapt to climate change, in this study we provide information that will assist farmers in their decision-making process for adaptation and in the selection of appropriate cultivars of deciduous fruits. Crop water use and chill unit requirements are modelled for the present and future climate. Results show that, irrespective of the irrigation system employed, climate change has led to increases in crop water use. Water use with the drip irrigation system was lower than with sprinkler irrigation as a result of efficiency differences in the irrigation technologies. It was also confirmed that the accumulated chill units will decrease in the future as a consequence of climate change. In order to remain in production, farmers need to adapt to climate change stress by putting in place water resources and crop management plans. Thus, producers must be furnished with a variety of adaptation or management strategies to overcome the impact of climate change.

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Impact of climate change on sediment yield in the Mekong River basin: a case study of the Nam Ou basin, Lao PDR

Hydrology and Earth System Sciences ◽

10.5194/hess-17-1-2013 ◽

2013 ◽

Vol 17 (1) ◽

pp. 1-20 ◽

Cited By ~ 88

Author(s):

B. Shrestha ◽

M. S. Babel ◽

S. Maskey ◽

A. van Griensven ◽

S. Uhlenbrook ◽

...

Keyword(s):

Climate Change ◽

Sediment Yield ◽

General Circulation ◽

Climate Models ◽

Greenhouse Gas Emission ◽

Circulation Model ◽

Sediment Flux ◽

Seasonal Temperature ◽

Impact Of Climate Change ◽

The Impact

Abstract. This paper evaluates the impact of climate change on sediment yield in the Nam Ou basin located in northern Laos. Future climate (temperature and precipitation) from four general circulation models (GCMs) that are found to perform well in the Mekong region and a regional circulation model (PRECIS) are downscaled using a delta change approach. The Soil and Water Assessment Tool (SWAT) is used to assess future changes in sediment flux attributable to climate change. Results indicate up to 3.0 °C shift in seasonal temperature and 27% (decrease) to 41% (increase) in seasonal precipitation. The largest increase in temperature is observed in the dry season while the largest change in precipitation is observed in the wet season. In general, temperature shows increasing trends but changes in precipitation are not unidirectional and vary depending on the greenhouse gas emission scenarios (GHGES), climate models, prediction period and season. The simulation results show that the changes in annual stream discharges are likely to range from a 17% decrease to 66% increase in the future, which will lead to predicted changes in annual sediment yield ranging from a 27% decrease to about 160% increase. Changes in intra-annual (monthly) discharge as well as sediment yield are even greater (−62 to 105% in discharge and −88 to 243% in sediment yield). A higher discharge and sediment flux are expected during the wet seasons, although the highest relative changes are observed during the dry months. The results indicate high uncertainties in the direction and magnitude of changes of discharge as well as sediment yields due to climate change. As the projected climate change impact on sediment varies remarkably between the different climate models, the uncertainty should be taken into account in both sediment management and climate change adaptation.

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Impact of climate change on hydropower production in the Upper Danube

10.5194/ems2021-493 ◽

2021 ◽

Author(s):

Ignacio Martin Santos ◽

Mathew Herrnegger ◽

Hubert Holzmann

Keyword(s):

Climate Change ◽

Spatial Resolution ◽

Transfer Functions ◽

Danube River ◽

Emission Scenarios ◽

Hydropower Generation ◽

Climate Change Projections ◽

Impact Of Climate Change ◽

The Future ◽

The Impact

In the last two decades, different climate downscaling initiatives provided climate scenarios for Europe. The most recent initiative, CORDEX, provides Regional Climate Model (RCM) data for Europe with a spatial resolution of 12.5 km, while the previous initiative, ENSEMBLES, had a spatial resolution of 25 km. They are based on different emission scenarios, Representative Concentration Pathways (RCPs) and Special Report on Emission Scenarios (SRES) respectively.A study carried out by Stanzel et al. (2018) explored the hydrological impact and discharge projections for the Danube basin upstream of Vienna when using either CORDEX and ENSEMBLES data. This basin covers an area of 101.810km2 with a mean annual discharge of 1923 m3/s at the basin outlet. The basin is dominated by the Alps, large gradients and is characterized by high annual precipitations sums which provides valuable water resources available along the basin. Hydropower therefore plays an important role and accounts for more than half of the installed power generating capacity for this area. The estimation of hydropower generation under climate change is an important task for planning the future electricity supply, also considering the on-going EU efforts and the &#8220;Green Deal&#8221; initiative.Taking as input the results from Stanzel et al. (2018), we use transfer functions derived from historical discharge and hydropower generation data, to estimate potential changes for the future. The impact of climate change projections of ENSEMBLE and CORDEX in respect to hydropower generation for each basin within the study area is determined. In addition, an assessment of the impact on basins dominated by runoff river plants versus basins dominated by storage plants is considered.The good correlation between discharge and hydropower generation found in the historical data suggests that discharge projection characteristics directly affect the future expected hydropower generation. Large uncertainties exist and stem from the ensembles of climate runs, but also from the potential operation modes of the (storage) hydropower plants in the future.&#160;&#160;References:Stanzel, P., Kling, H., 2018. From ENSEMBLES to CORDEX: Evolving climate change projections for Upper Danube River flow. J. Hydrol. 563, 987&#8211;999. https://doi.org/10.1016/j.jhydrol.2018.06.057&#160;

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