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Climate Change Impacts on Water Availability and Use in the Limpopo River Basin

Authors:
Tingju Zhu at Zhejiang University
Tingju Zhu
Claudia Ringler at International Food Policy Research Institute
Claudia Ringler
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This paper analyzes the effects of climate change on water availability and use in the Limpopo River Basin of Southern Africa, using a linked modeling system consisting of a semi-distributed global hydrological model and the Water Simulation Module (WSM) of the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT). Although the WSM simulates all major water use sectors, the focus of this study is to evaluate the implications of climate change on irrigation water supply in the catchments of the Limpopo River Basin within the four riparian countries: Botswana, Mozambique, South Africa, and Zimbabwe. The analysis found that water resources of the Limpopo River Basin are already stressed under today’s climate conditions. Projected water infrastructure and management interventions are expected to improve the situation by 2050 if current climate conditions continue into the future. However, under the climate change scenarios studied here, water supply availability is expected to worsen considerably by 2050. Assessing hydrological impacts of climate change is crucial given that expansion of irrigated areas has been postulated as a key adaptation strategy for Sub-Saharan Africa. Such expansion will need to take into account future changes in water availability in African river basins.
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Climate Change Impacts on Water Availability and Use in the Limpopo River Bas
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... Due to climate change and variability, Limpopo Province has steadily decreased precipitation over the past few decades. It will become increasingly challenging to ensure a reliable water supply in the river basin in the future (Zhu & Ringler, 2012). Due to rising temperatures, higher rates of evaporation, less predictable rainfall amounts, and more frequent floods caused by intense rainfall, the amount of water in rivers is expected to decline as the climate changes (Davis, 2010;Joseph et al., 2021). ...
... South Africa ranges from semi-arid to dry, and its scarce water supplies are depleted by the erratic weather patterns brought on by global warming. Zhu and Ringler (2012) predict that by 2050, South Africa will face severe shortages in its water supply. In a predominantly agricultural province (Limpopo), where roughly 48% of the population lacks access to piped water within their residence or yard, the likelihood of increased water stress is substantial (SANBI, 2011;Zhu & Ringler, 2012). ...
... Zhu and Ringler (2012) predict that by 2050, South Africa will face severe shortages in its water supply. In a predominantly agricultural province (Limpopo), where roughly 48% of the population lacks access to piped water within their residence or yard, the likelihood of increased water stress is substantial (SANBI, 2011;Zhu & Ringler, 2012). There is a growing concern that drought, one of the world's most destructive natural disasters, could adversely affect agriculture, water supply, energy production, and public health in areas with annual rainfall of less than 500 mm (Patrick, 2021). ...
A Review of Rural Communities’ Vulnerability to Climate Change: The Case of Limpopo Province in South Africa
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  • Nov 2023
Climate change threatens the livelihood of rural communities that depend on climate-sensitive resources. The risks and consequences of climate change, to which rural areas are especially susceptible, are discussed in this review. The review summarizes previous studies on rural communities' susceptibility to the impacts of changing climatic conditions. Previous studies on climate change in South Africa's Limpopo Province provide the information used in this review. The findings indicate that rural communities are vulnerable to rising temperatures and unpredictable precipitation. The communities are exposed to higher temperatures, less rainfall, and intermittent drought. Subsistence agricultural and livestock production and water supplies are two examples of climate-dependent livelihood resources vulnerable to weather variability and change. These resulted in food insecurity and water scarcity in many rural areas. This review helps fill a gap in understanding the importance of assessing the vulnerability of rural communities with climate-dependent livelihood resources. The study recommends detailed community-based adaptation measures to counteract the detrimental effects of climatic stresses on people's means of subsistence. Adaptation policies to climate change could be strengthened by incorporating indigenous adaptation techniques and community voices into response efforts.
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... In IMPACT, the effects of water on agricultural production are implemented through several key variables, including effective rainfall, potential crop evapotranspiration and applied irrigation water, which in turn depends on both crop irrigation water requirements and SW and GW availability. SW availability is simulated by the IGHM at monthly intervals for 0.5° grid cells 52 . Irrigation water supply is simulated by the IWSM, which operates at the FPU level and is dynamically coupled with the IMPACT core multi-market model through annual iterations (monthly in IWSM and IGHM) for the period 2005-2050 (Supplementary Fig. 3) 33 . ...
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... Among the frequently employed hydrological models are the Soil and Water Assessment Tool (SWAT), Hydrologiska Byråns Vattenbalansavdelning (HBV), Topographic model (TOPMODEL), Variable Infiltration Capacity (VIC), Hydro-Informatic Modelling System (HIMS), and Spatial Process in Hydrology (SPHY). Based on several models, the studies have consistently emphasized the susceptibility of snowcapped mountains to the impacts of global climate change (Khadka et al. 2014;Kim and Kaluarachchi 2009;Kure et al. 2013;Manandhar et al. 2013;Ougahi et al. 2023;Pandey et al. 2019;Shrestha et al. 2018;Versini et al. 2016;Zhu and Ringler 2012). Furthermore, Kumar and Joshi (2019) used SWAT in the Upper Watershed of the River Subarnarekha in India to examine impact of precipitation on water balance. ...
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Article
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  • Jan 2024
  • ENVIRON EARTH SCI
Sustainable water resource management has become increasingly challenging due to the limited availability of hydrometeorological data in remote mountainous areas, making it difficult to assess water balance and simulate runoff at various spatiotemporal scales. This study aims to assess the 30-year (1990–2019) water balance of the Chameliya Watershed in the Mahakali River Basin, Nepal, with a focus on glacier dynamics, utilizing the Spatial Process in Hydrology (SPHY) modeling tool. The data analysis disclosed that the watershed experienced positive water balance for 6 months, primarily during the monsoon season, while the remaining months exhibited negative values. Additionally, a comparison between the recent decade (2010–2019) and the late 1990s revealed an increase in hydrological components, such as discharge and precipitation, alongside a decrease in evapotranspiration and glacier melt. The dynamics of discharge disclose fluctuations among multiple contributors, with rainfall taking precedence, followed by baseflow, snowmelt, and glacier melt in descending sequence. Overall, the study offers a profound understanding of water availability in the Chameliya Watershed and highlights its dynamic changes over the study period. This knowledge holds great significance, especially in remote, inaccessible, and high-altitude regions. It also underscores the necessity of understanding Himalayan hydrological dynamics for precise flood prediction, climate risk assessment, and sustainable resource management amid global climate change.
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... The (semi-)arid Limpopo basin, located in southern Africa (Fig. 10.3), is one of the most water-stressed basins in Africa and is expected to face even more serious water scarcity issues in the future, limiting economic development in the basin (Zhu and Ringler, 2012). Hydrological droughts and their space-time variability are schematized using a process-based distributed hydrological model. ...
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... The (semi) arid Limpopo basin, located in southern Africa (Figure 10.4), is one of the most water-stressed basins in Africa and is expected to face even more serious water scarcity issues in the future, limiting economic development in the basin (Zhu and Ringler, 2012). Hydrological droughts and their spaceetime variability are schematized using a process-based distributed hydrological model. ...
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... Croplands across the LRB are populated by primarily rainfed maize, sorghum, and millet, as well as some irrigated fields for cultivating tropical fruits such as mangos and bananas year-round. "Blue water" irrigation is made possible by both groundwater and surface water abstraction, which is supplemented by reservoirs formed by dams, one of which is the Massingir Dam in the Oliphants sub-watershed [4,[66][67][68][69][70]. Forested regions are made up of both native forests and commercial plantations of exotic species (e.g., pine, eucalyptus) in the escarpment and mountainous region of South Africa [4,66]. ...
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Article
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... In IMPACT, the effects of water on agricultural production are channeled through key variables including effective rainfall, maximum crop evapotranspiration, and applied irrigation water, which in turn depends on both crop irrigation water requirements and SW and GW availability. SW availability is simulated by the IGHM at monthly intervals for 0.5-degree grid cells 52 ...
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International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT): Model Description
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THE MODEL.................................................................................................................................7 I. Basic Methodology on Food............................................................................................. 7
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Article
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