Impact of Climate Change on Water Resources in Rwanda: A Case of Muvumba Catchment
DOI:
https://doi.org/10.53819/81018102t2253Abstract
Climate change profoundly impacts water resources, affecting people's well-being, agriculture, industry, and urban development due to altered weather patterns. This study focuses on Rwanda's Muvumba catchment, aiming to assess climate change effects. Analyzing global (World Clim, GCMs, CMIP6) and national data sets, remote sensing (SRTM elevation data, DEM) generated insights on precipitation, evaporation, and temperature changes during 2012-2021 and projected 2021-2040. Employing GIS, HEC-HMS model, and remote sensing, a hydrological model evaluates Muvumba catchment's river discharge, informing effective implementation of mitigation and adaptation strategies. Analysis indicated fluctuating minimum temperatures (14°C to 17°C) and maximum annual temperatures (27°C to 28.3°C) in 2012-2021, with a 0.4°C rise in maximum temperature over the decade. Averaging 21.6°C to 22.5°C, increased evaporation heightened water body depletion, impacting Muvumba catchment's water availability, exacerbating drought and scarcity. Projections for 2021-2040 anticipate March at 15.01°C as the coldest month, while July hits 28.7°C. Mean temperature may range from 21°C to 23.3°C, with a projected 0.82°C increase. Notably, annual precipitation peaked in 2020 at 1176.31 mm and hit a low in 2017 with 628.77 mm, emphasizing the water stress issue. It was found that the impacted location was the Mulindi sub-catchment, which is susceptible to floods and soil erosion, with the silt end up as sediments in rivers and streams. Research indicated the prediction of 1033.68mm annual rainfall in 2012-2040. Over 20 years it is predicted the reduction of 18.76 mm of precipitation, the highest annual evaporation rate was 2013, indicated 3.83mm which led to more water lost from water bodies. From2012 to 2021 water quality level was varied between 7.6 pH and 7.35 pH which facilitated the release of toxic substances from sediments into water further impacting water quality. Future water demand and use scenarios show that water stress in Muvumba will gradually increase, river discharges reduced by 2019 and 2020 due to decreased precipitation, LULCCD showed reduction of 17% of forests which lead to high rises of temperature .The average monthly discharge is projected to decrease from June to August (Long dry season) by variation of 4.7 and 7.8%by 2021-2040. Large increase of stream flow is projected to occur in April and May by variation of 13 and 14.7%. The research recommended the upgrading and maintaining existing stations and calibrating meteorological instruments, including weather radar, to give all climate information required for future observing, climate trend detection, climate variability management, afforestation, early warning, and disaster management.
Keyword: Climate change, Hydrological Modeling, Temperature, Precipitation, Evaporation and Water resources, Rwanda
References
Abate, M. A., & Dile, Y. T. (2021). Modeling the impact of climate change on the hydrology of Andasa watershed. Modeling Earth Syst. Environ., 1-17.
Daba, M., & You, S. (2020). Assessment of Climate Change Impacts on River Flow Regimes in the Upstream of Awash basin, Ethiopia:. Based on IPCC Fifth Assessment Report (AR5) Climate Change Scenarios. Hydrology, 7, 98.
Getahun. (2014). Impact of Climate Change on Hydrology of the Upper Awash River Basin(Ethiopia):. Inter-Comparison of Old SRES and New RCP Scenarios.Ph.D. Thesis, Wageningen University,Wageningen, The Netherlands,
Gurara, M., Jilo, N., & Tolche, A. (2021). Modeling Climate Change Impact on the Streamflow in the Upper Wabe Bridge Watershed in Wabe Shebele River Basin, Ethiopia. Int. J. River Basin Manag., 1-46.
Hijmans, R. J. (2012). DIVA-GIS Version 7.5 Manual. 71.
IPCC. (2018). GLOBAL WARMING OF 1 . 5 ° C an IPCC special report on the impacts of global.
IPCC. (2021). The Physical Science Basis Summary for Policymakers Working Group I Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change.
Kedir, S. a. (2008). Assessment of Climate Change Impacts on the Hydrology of Gilgel Abbay Catchment in Lake Tana Basin, Ethiopia.
Merwade, V. (2012). Hydrologic Modeling using HEC-HMS Opening a HEC-HMS project.
MIDIMAR. (2015). National risk atlas of Rwanda.
MINECOFIN. (2017). National Strategy for Tranformation-1, draft- under finalisation 28th December 2017;
MINIRENA-RNRA. (2015). RWANDA NATIONAL WATER RESOURCES MASTER PLAN.
NISR. (2012). Size of the resident population | National Institute of Statistics Rwanda.
NMSA. (2001). Initial National Communication of Ethiopia to the United Nations Framework Convention on climate change(UNFCCC),. National Meteorological services Agency,Addis Ababa,Ethiopia.
OECD. (2018). Climate resilience infrastructure.
Ong, T., & Phing, P. N. (2012). Capital structure before and after merger and acquisition: Banking industry in Malaysia. International Journal of Management Sciences and Business Research.
Onyutha, C., Asiimwe, A., Ayugi, B., Ngoma, H., Ongoma, V., & Tabari, H. (2021). Observed and Future Precipitation and Evapotranspiration in Water Management Zones of Uganda:. CMIP6 Projections. Atmosphere 2021, 12, 887.
REMA. (2018). Climate change vulnerability report.
Rwanda Water for Growth. (2017). Catchment Plan Muvumba 2017-2023. s.l.: Integrated Water Resources Management (IWRM).
Sheffield, J. (2008). Global trends and variability in soil moisture and drought characteristics,1950-2000,from observation-driven simulations of the terrestrial hydrologic cycle. Journal of Climate, 21(3),432-458.).
Tessema, . (2021). Modelling the effects of climate change on streamflow using climate and hydrological models:The case of the Kesem sub-basin of the Awash River basin, Ethiopia. Int. J. River Basin Manag., 19, 469–480.
Tessema, N., Kebede, A., & Yadeta, D. (2021). Modelling the effects of climate change on streamflow using climate and hydrological models:The case of the Kesem sub-basin of the Awash River basin, Ethiopia. Int. J. River Basin Manag, 19, 469–480.
UN-Water. (2019). Climate Change and Water UN-Water Policy Brief. The UN-Water Expert Group on Water and Climate Change UN-Wate Policy Brief, 28.
USGS. (2009). "Earth's water distribution". (http://ga.water.usgs.gov/edu/waterdistribution.html).
USGS. (2012). Natural Processes of Ground-Water and Surface-Water Interaction: The Hydrologic Cycle and Interactions of Ground Water and Surface Water. Aquatic science, 2-32.
World bank. (2022). RWANDA: Economic Update. Africa Research Bulletin: Economic, Financial and Technical Series.
