Abstract
The West African climate has evolved in recent decades to respond to elevated anthropogenic greenhouse gas (GHG) forcing. An assessment of its recent trends and future changes is presented here based on various data sources (observations and models), along with an extensive review of recent literature including the latest Intergovernmental Panel on Climate Change report. A gradual warming spatially variable reaching 0.5 °C per decade in recent years is observed. In addition, the Sahel has recovered from the previous drought episodes (i.e., 1970s and 1980s); however, the precipitation amount is not at the level of the pre-drought period. Although these features are common across the different data sources, their magnitudes differ from one source to the other due to a lack of reliable observation systems. Projected climate change indicates continuous and stronger warming (1.5–6.5 °C) and a wider range of precipitation uncertainty (roughly between −30 and 30 %) larger in the Sahel and increasing in the farther future. However, the spatial distribution unveils significant precipitation decrease confined to the westernmost Sahel and becoming greater and more extensive in the high level GHG forcing scenario by the end of the 21st century. This coexists with a substantial increase in both dry spell length and extreme precipitation intensity. West Sahel is thus the most sensitive region to anthropogenic climate change. The rest of West Africa also experiences more intense extremes in future climate but to a lesser extent. It is also reported from other previous studies that the projected rainy season and the growing season will become shorter while the torrid, arid and semi-arid climate conditions will substantially extend. It is thus evident that in a “business as usual” World, most countries in West Africa will have to cope with shorter rainy seasons, generalized torrid, arid and semi-arid conditions, longer dry spells and more intense extreme precipitations. Such conditions can produce significant stresses on agricultural activities, water resources management, ecosystem services and urban areas planning. However, some GHG mitigation (i.e., a mid-level forcing) could help to reduce the stress.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Abiodun, B. J., Lawal, K. A., Salami, A. T., & Abatan, A. A. (2013). Potential influences of global warming on future climate and extreme events in Nigeria. Regional Environmental Change, 13, 477–491. doi:10.1007/s10113-012-0381-7.
Ackerley, D., Booth, B. B. B., Knight, S. H. E., Highwood, E. J., Frame, D. J., Allen, M. R., & Rowell, D. P. (2011). Sensitivity of twentieth-century sahel rainfall to sulfate aerosol and CO2 forcing. Journal of Climate, 24, 499–5014. doi:10.1175/JCLI-D-11-00019.1.
Anyamba, A., Small, J. L., Britch, S. C., Tucker, C. J., Pak, E. W., Reynolds, C. A., et al. (2014). Recent weather extremes and impacts on agricultural production and vector-borne disease outbreak patterns. PLoS ONE, 9(3), e92538. doi:10.1371/journal.pone.0092538.
Biasutti, M., & Sobel, A. (2009). Delayed Sahel rainfall and global seasonal cycle in a warmer climate. Geophysical Research Letters, 36(L23), 707. doi:10.1029/2009GL041303.
Biasutti, M. (2013). Forced Sahel rainfall trends in the CMIP5 archive. Journal of Geophysical Research: Atmospheres, 118, 1613–1623. doi:10.1002/jgrd.50206.
Boko, M., Niang, I., Nyong, A., Vogel, C., Githeko A, Medany, M., Osman-Elasha, B., Tabo, R., & Yanda, P. (2007). Africa Climate Change 2007: impacts, adaptation and vulnerability. In M. L. Parry, O. F. Canziani, J. P. Palutikof, P. J. van der Linden, & C. E. Hanson (Eds.), Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (pp. 433–467). Cambridge, UK: Cambridge University Press.
Carney, L. T., Reinsch, S. S., Lane, P. D., Solberg, O. D., Jansen, L. S., Williams, K. P., et al. (2014). Microbiome analysis of a micro algal mass culture growing in municipal waste water in a prototype OMEGA photobioreactor. Algal Research, 4, 52–61. doi:10.1016/j.algal.2013.11.006.
Cook, K. H., & Vizy, E. K. (2012). Impact of climate change on mid-twenty-first century growing seasons in Africa. Climate Dynamics, 39, 2937–2955. doi:10.1007/s00382-012-1324-1.
Dai, A. (2013). Increasing drought under global warming in observations and models. Nature Climate Change, 3, 52–58. doi:10.1038/nclimate1633.
Diallo, I., Sylla, M.B., Giorgi, F., Gaye, A.T., & Camara, M. (2012). Multi-model GCM-RCM ensemble based projections of temperature and precipitation over West Africa for the early 21st century. International Journal of Geophysics, 972896. doi:10.1155/2012/972896.
Diallo, I., Sylla, M. B., Camara, M., & Gaye, A. T. (2013). Interannual variability of rainfall over the Sahel based on multiple regional climate models simulations. Theoretical and Applied Climatology, 113(1–2), 351–362. doi:10.1007/s00704-012-0791-y.
Dong, B. W., & Sutton, R. (2015). Dominant role of greenhouse gas forcing in the recovery of Sahel rainfall. Nature Climate Change, 5, 757–760. doi:10.1038/nclimate2664.
Dosio, A., Panitz, H. J. (2015) Climate change projections for CORDEX-Africa with COSMO-CLM regional climate model and differences with the driving global climate models. Climate Dynamics. doi:10.1007/s00382-015-2664-4 (in press).
Dosio, A., Panitz, H. J., Schubert-Frisius, M., & Lüthi, D. (2015). Dynamical downscaling of CMIP5 global circulation models over CORDEX-Africa with COSMO-CLM: Evaluation over the present climate and analysis of the added value. Climate Dynamics, 44, 2637–2661. doi:10.1007/s00382-014-2262-x.
Douglas, I., Alam, K., Maghenda, M., McDonnell, Y., Mclean, L., & Campbell, J. (2008). Unjust waters: Climate change, flooding and the urban poor in Africa. Environment and Urbanisation, 20, 187–205. doi:10.1177/0956247808089156.
Druyan, L. M. (2011). Studies of 21st-century precipitation trends over West Africa. International Journal of Climatology, 31(10), 1415–1424. doi:10.1002/joc.2180.
Elguindi, N., Grundstein, A., Bernardes, S., Turuncoglu, U., & Feddema, J. (2014). Assessment of CMIP5 global model simulations and climate change projections for the 21st Century using a modified Thornthwaite climate classification. Climatic Change, 122, 523–538. doi:10.1007/s10584-013-1020-0.
Fontaine, B., Roucou, P., Gaetani, M., & Marteau, R. (2011). Recent changes in precipitation, ITCZ convection and northern tropical circulation over North Africa (1979–2007). International Journal of Climatology, 31(5), 633–648.
Gbobaniyi, E., Sarr, A., Sylla, M. B., Diallo, I., Lennard, C., Dosio, A., et al. (2014). Climatology, annual cycle and interannual variability of precipitation and temperature in CORDEX simulations over West Africa. International Journal of Climatology, 34(7), 2241–2257. doi:10.1002/joc.3834.
Giorgi, F., Jones, C., Asrar, G. (2009). Addressing climate information needs at the regional level. The CORDEX framework. WMO Bulletin, July 2009 issue.
Giorgi, F., Im, E. S., Coppola, E., Diffenbaugh, N. S., Gao, X. J., Mariotti, L., & Shi, Y. (2011). Higher hydroclimatic intensity with global warming. Journal of Climate, 24, 5309–5324. doi:10.1175/2011JCLI3979.1.
Giorgi, F., Coppola, E., & Raffaele, F. (2014a). A consistent picture of the hydroclimatic response to global warming from multiple indices: Models and observations. Journal of Geophysical Research: Atmosphere, 119. doi:10.1002/2014JD022238.
Giorgi, F., Coppola, E., Raffaele, F., Diro, G. T., Fuentes-Franco, R., Giuliani, G., Mamgain, A., Llopart, M. P., Mariotti, L., & Torma, C. (2014b). Changes in extremes and hydroclimatic regimes in the CREMA ensemble projections. Climatic Change, 125, 39–51. doi:10.1007/s10584-014-1117-0.
Haarsma, R. J., Selten, F. M., Weber, S. L., & Kliphuis, M. (2005). Sahel rainfall variability and response to greenhouse warming. Geophysical Research Letter, 32, L17702. doi:10.1029/2005GL023232.
Haensler, A., Saeed, F., & Jacob, D. (2013). Assessing the robustness of projected precipitation changes over central Africa on the basis of a multitude of global and regional climate projections. Climatic Change, 121(2), 349–363. doi:10.1007/s10584-013-0863-8.
Hagos, S. M., & Cook, K. H. (2008). Ocean warming and late-twentieth-century Sahel drought and recovery. Journal of Climate, 21(15), 3797–3814. doi:10.1175/2008JCLI2055.1.
Harris, I., Jones, P. D., Osborn, T. J., & Lister, D. H. (2014). Updated high-resolution grids of monthly climatic observations—the CRU TS3.10 Dataset. International Journal of Climatology, 34, 623–642. doi:10.1002/joc.3711.
Hartmann, D. L., Klein Tank, A. M. G., Rusticucci, M., Alexander, L. V., Brönnimann, S., Charabi, Y., Dentener, F. J., Dlugokencky, E. J., Easterling, D. R., Kaplan, A., Soden, B. J., Thorne, P.W., Wild, M. & Zhai, P. M. (2013). Observations: Atmosphere and surface. In: T. F. Stocker, D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex & P. M. Midgley (Eds.), Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press.
Ibrahim, B., Karambiri, H., Polcher, J., Yacouba, H., & Ribstein, P. (2014). Changes in rainfall regime over Burkina Faso under the climate change conditions simulated by 5 regional climate models. Climate Dynamics, 42, 1363–1381. doi:10.1007/s00382-013-1837-2.
IPCC. (2013). Climate Change 2013: The Physical Science Basis. In T. F. Stocker, D. Qin, G. -K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex & P. M. Midgley (Eds.), Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (p. 1535). Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press. doi:10.1017/CBO9781107415324.
Riede, J. O., Posada, R., Fink, A. H., & Kaspar, F. (2016). What’s on the 5th IPCC Report for West Africa?. In: J. A. Yaro & J. Hesselberg (Eds.), Adaptation to Climate Change and Variability in Rural West Africa. Springer, Switzerland.
Jones, C., Giorgi, F., & Asrar, G. (2011). The coordinated regional downscaling experiment: CORDEX an international downscaling link to CMIP5. CLIVAR Exchanges, 56(16), 34–40.
Karl, T. R., Arguez, A., Huang, B., Lawrimore, J. H., Menne, M. J., Peterson, T. C., Vose, R. S., & Zhang, H. M. (2015, June). Possible artifacts of data biases in the recent global surface warming hiatus. Science, 348(6242), 1469–1472. doi:10.1126/science.aaa5632.
Klutse, N. A. B., Sylla, M. B., Diallo, I., Sarr, A., Dosio, A., Diedhiou, A., Kamga, A., Lamptey, B., Ali, A., Gbobaniyi, E.O., Owusu, K., Lennard, C., Hewitson, B., Nikulin, G., Panitz, H. J., & Büchner, M. (2015). Daily characteristics of West African monsoon rainfall in CORDEX regional climate models. Theoretical and Applied Climatology. doi:10.1007/s00704-014-1352-3 (In press).
Lambin, E. F., Geist, H. J., & Lepers, E. (2003). Dynamics of land-use and land-cover change in tropical regions. Annual Review of Environment and Resources, 28, 205–241. doi:10.1146/annurev.energy.28.050302.105459.
Laprise, R., Hernández-Díaz, L., Tete, K., et al. (2013). Climate projections over CORDEX Africa domain using the fifth-generation Canadian Regional Climate Model (CRCM5). Climate Dynamics, 41(11), 3219–3246. doi:10.1007/s00382-012-1651-2.
Lebel, T., & Ali, A. (2009). Recent trends in the Central and Western Sahel rainfall regime (1990–2007). Journal of Hydrology, 375(1–2), 52–64. doi:10.1016/j.jhydrol.2008.11.030.
Legates, D. R., & Willmott, C. J. (1990). Mean seasonal and spatial variability in gauge-corrected, global precipitation. International Journal of Climatology, 10(2), 111–127. doi:10.1002/joc.3370100202.
Leh, M. D. K., Matlock, M. D., Cummings, E. C., & Nalley, L. L. (2013). Quantifying and mapping multiple ecosystem services change in west Africa. Agriculture, Ecosystems & Environment, 165, 6–18. doi:10.1016/j.agee.2012.12.001.
Lintner, B. R., Biasutti, M., Diffenbaugh, N. S., Lee, J. E., Niznik, M. J., & Findell, K. L. (2012). Amplification of wet and dry month occurrence over tropical land regions in response to global warming. Journal of Geophysical Research, 117, D11106. doi:10.1029/2012JD017499.
Lobell, D. B., Schlenker, W. S., & Costa-Roberts, J. (2011). Climate trends and global crop production since 1980. Science, 333, 616–620. doi:10.1126/science.1204531.
Mahe, G., & Paturel, J. E. (2009). 1896–2006 Sahelian annual rainfall variability and runoff increase of Sahelian Rivers. Comptes Rendues Geosciences, 341(7), 538–546. doi:10.1016/j.crte.2009.05.002.
Mariotti, L., Diallo, I., Coppola, E., & Giorgi, F. (2014). Seasonal and intraseasonal changes of African monsoon climates in 21st century CORDEX projections. Climatic Change, 125, 53–65. doi:10.1007/s10584-014-1097-0.
Mohino, E., Janicot, S., & Bader, J. (2011). Sahel rainfall and decadal to multi-decadal sea surface temperature variability. Climate Dynamics, 37(3), 419–440. doi:10.1007/s00382-010-0867-2.
Moss, R. H., Edmonds, J. A., Hibbard, K. A., Manning, M. R., Rose, S. K., van Vuuren, D. P., Carter, T. R., Emori, S., Kainuma, M., Kram, T., Meehl, G. A., Mitchell, J. F. B., Nakicenovic, N., Riahi, K., Smith, S. J., Stouffer R. J., Thomson, A. M., Weyant, J. P., & Wilbanks, T. J. (2010). The next generation of scenarios for climate change research and assessment. Nature, 463, 747–756. doi:10.1038/nature08823.
Nicholson, S. (2005). On the question of the “recovery” of the rains in the West African Sahel. Journal of Arid Environments, 63(3), 615–641.
Nikulin, G., Jones, C., Giorgi, F., Asrar, G., Büchner, M., Cerezo-Mota, R., et al. (2012). Precipitation climatology in an ensemble of CORDEX-Africa regional climate simulations. Journal of Climate, 25, 6057–6078. doi:10.1175/JCLI-D-11-00375.1.
Novella, N. S., & Thiaw, W. M. (2013). African rainfall climatology version 2 for famine early warning systems. Journal of Applied Meteorology and Climatology, 52, 588–606. doi:10.1175/JAMC-D-11-0238.1.
Padgham, J., Jabbour, J., & Dietrich, K. (2015). Managing change and building resilience: A multi-stressor analysis of urban and peri-urban agriculture in Africa and Asia. Urban Climate, 12, 183–204. doi:10.1016/j.uclim.2015.04.003.
Parry, M. L., Canziani, O. F., Palutikof, J. P., van der Linden, P. J., & Hanson, C. E. (2007). Climate change 2007: impacts, adaptation and vulnerability. In Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (p. 976). Cambridge, UK: Cambridge University Press.
Roehrig, R., Bouniol, D., Guichard, F., Hourdin, F., & Redelsperger, J. L. (2013). The present and future of the West African monsoon: a process-oriented assessment of CMIP5 simulations along the AMMA transect. Journal of Climate, 26, 6471–6505. doi:10.1175/JCLI-D-12-00505.1.
Teichmann, C., Eggert, B., Elizalde, A., Haensler, A., Jacob, D., Kumar, P., et al. (2013). How does a regional climate model modify the projected climate change signal of the driving GCM: A study over different CORDEX regions using REMO. Atmosphere, 4(2), 214–236. doi:10.3390/atmos4020214.
Sarr, B. (2012). Present and future climate change in West Africa: A crucial input for agricultural research prioritization for the region. Atmospheric Science Letter, 13, 108–112. doi:10.1002/asl.368.
Schewe, J., Heinke, J., Gerten, D., Haddeland, I., Arnell, N. W., Clark, D. B., et al. (2014). Multi-model assessment of water scarcity under climate change. PNAS, 111(9), 3245–3250. doi:10.1073/pnas.1222460110.
Scoccimarro, E., Gualdi, S., Bellucci, A., Zampieri, M., & Navarra, A. (2013). Heavy precipitation events In a warmer climate: results from CMIP5 models. Journal of Climate, 26, 7902–7911. doi:10.1175/JCLI-D-12-00850.1.
Seth, A., Rauscher, S. A., Biasutti, M., Giannini, A., Camargo, S. J., & Rojas, M. (2013). CMIP5 projected changes in the annual cycle of precipitation. Journal of Climate, 26, 7328–7351. doi:10.1175/JCLI-D-12-00726.1.
Sylla, M. B., Gaye, A. T., Jenkins, G. S., Pal, J. S., & Giorgi, F. (2010a). Consistency of projected drought over the Sahel with changes in the monsoon circulation and extremes in a regional climate model projections. Journal of Geophysical Research-Atmosphere, 115, D16108. doi:10.1029/2009JD012983.
Sylla, M.B., Dell’Aquila, A., Ruti, P. M., & Giorgi, F. (2010b). Simulation of the intraseasonal and the interannual variability of rainfall over West Africa with RegCM3 during the monsoon period. International Journal of Climatology, 30, 1865–1883. doi:10.1002/joc.2029.
Sylla, M. B., Giorgi, F., Ruti, P. M., Calmanti, S., & Dell’Aquila, A. (2011). The impact of deep convection on the West African summer monsoon climate: A regional climate model sensitivity study. Quarterly Journal of Royal Meteorological Society, 137, 1417–1430. doi:10.1002/qj.853.
Sylla, M. B., Gaye, A. T., & Jenkins, G. S. (2012). On the fine-scale topography regulating changes in atmospheric hydrological cycle and extreme rainfall over West Africa in a regional climate model projections. International Journal of Geophysics, 981649. doi:10.1155/2012/981649.
Sylla, M. B., Giorgi, F., Coppola, E., & Mariotti, L. (2013a). Uncertainties in daily rainfall over Africa: Assessment of observation products and evaluation of a regional climate model simulation. International Journal of Climatology, 33, 1805–1817. doi:10.1002/joc.3551.
Sylla, M. B., Diallo, I., & Pal, J. S. (2013b). West African monsoon in state-of-the-science regional climate models, Climate Variability—Regional and Thematic Patterns, Dr. Aondover Tarhule (Ed.), ISBN: 978-953-51-1187-0, InTech. doi:10.5772/55140.
Sylla, M. B., Elguindi, N., Giorgi, F., & Wisser, D. (2016). Projected robust shift of climate zones over West Africa in response to anthropogenic climate change for the late 21st century. Climatic Change, 134(1), 241–253. doi:10.1007/s10584-015-1522-z.
Sylla, M. B., Giorgi, F., Pal, J. S., Gibba, P., Kebe, I., & Nikiema, M. (2015). Projected changes in the annual cycle of high intensity precipitation events over West Africa for the late 21st century. Journal of Climate, 28, 6475–6488. doi:10.1175/JCLI-D-14-00854.1.
Taylor, K. E., Stouffer, R. J., & Meehl, G. A. (2012). An overview of CMIP5 and the experiment design. Bulletin American Meteorological Society, 93, 485–498. doi:10.1175/BAMS-D-11-00094.1.
Vizy, E. K., & Cook, K. H. (2012). Mid-twenty-first-century changes in extreme events over northern and tropical Africa. Journal of Climate, 25(17), 5748–5767. doi:10.1175/JCLI-D-11-00693.1.
WMO. (1986). Report on drought and countries affected by drought during 1974–1985. WCP-118, Geneva.
WMO. (1989). Statistical distributions for flood frequency analysis. Operational Hydrology Report 33. WMO no 718.
Zwiers, F.W., Alexander, L. V., Hegerl, G. C., Knutson, T. R., Kossin, J., Naveau, P., Nicholls, N., Schär, C., Seneviratne, S. I., & Zhang, X. (2013). Challenges in estimating and understanding recent changes in the frequency and intensity of extreme climate and weather events. In G. R. Asrar & J. W. Hurrell (Eds.), Climate Science for Serving Society: Research, Modeling and Prediction Priorities. doi 10.1007/978-94-007-6692-1_13.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2016 Springer International Publishing Switzerland
About this chapter
Cite this chapter
Sylla, M.B., Nikiema, P.M., Gibba, P., Kebe, I., Klutse, N.A.B. (2016). Climate Change over West Africa: Recent Trends and Future Projections. In: Yaro, J., Hesselberg, J. (eds) Adaptation to Climate Change and Variability in Rural West Africa. Springer, Cham. https://doi.org/10.1007/978-3-319-31499-0_3
Download citation
DOI: https://doi.org/10.1007/978-3-319-31499-0_3
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-31497-6
Online ISBN: 978-3-319-31499-0
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)