In recent years, Senegal has been confronted with increasingly frequent and damaging extreme events. In the context of climate change, we conducted this study to characterize the trends of rainfall extremes in Senegal. In this work, we used daily rainfall data from 27 stations in Senegal from the period 1951 to 2005 (55 years). To study their linear trends, non-stationary extreme value models with time as a covariate are fitted to evaluate them. Our results indicate a decreasing trend of extreme rainfalls at most of the stations except for 5 stations. However, the decreasing trends are only significant for two stations (Thiès and Kidira), however, this can only be taken as information that climate change may have already impacted extreme rainfalls. For the 20-year and 30-year return periods, the results show that they have undergone changes, in fact for almost all stations, the trends in return periods are decreasing.
References
[1]
Center, A.R. (2010) Le Sahel face aux changements climatiques. Enjeux pour un développement durable. Bulletin mensuel/numéro spécial. http://portails.cilss.bf/IMG/pdf/specialChC.pdf
[2]
Mondiale, L.B. (2010) Rapport sur le développement dans le monde 2010: Développement et changement climatique. Pearson Education, France.
[3]
Goubanova, K. (2007) Une étude des événements climatiques extrêmes sur l’Europe et le bassin Méditerranéen et de leur évolution future. Doctoral Dissertation, Université Paris VI, France. https://www.lmd.jussieu.fr/~li/atelier_cc/these_katerina.pdf
[4]
Panthou, G. (2013) Analyse des extrêmes pluviométriques en Afrique de l’Ouest et de leurs évolution au cours des 60 dernières années. Doctoral Dissertation, Université de Grenoble, France.
[5]
Marty, C. and Blanchet, J. (2012) Long-Term Changes in Annual Maximum Snow Depth and Snowfall in Switzerland Based on Extreme Value Statistics. Climatic Change, 111, 705-721. https://doi.org/10.1007/s10584-011-0159-9
[6]
Team, C.W. (2007) Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. IPCC 2007: Climate Change 2007: Synthesis Report. IPCC, Geneva, Switzerland, 104 p.
[7]
Beguería, S., Angulo-Martínez, M., Vicente-Serrano, S.M., López-Moreno, J.I. and El-Kenawy, A. (2011) Assessing Trends in Extreme Precipitation Events Intensity and Magnitude Using Non-Stationary Peak-Sover-Threshold Analysis: A Case Study in Northeast Spain from 1930 to 2006. International Journal of Climatology, 31, 2102-2114. https://doi.org/10.1002/joc.2218
[8]
Brown, S.J., Caesar, J. and Ferro, C.A. (2008) Global Changes in Extreme Daily Temperature since 1950. Journal of Geophysical Research: Atmospheres, 113, D05115. https://doi.org/10.1029/2006JD008091
[9]
Sene, S. and Ozer, P. (2002) Evolution pluviométrique et relation inondationsévénements pluvieux au Sénégal. Bulletin de la Société géographique de Liège, 42, 27-33.
[10]
Mann, H. (1945) Non Parametric Test against Trend. Econometrika, 13, 245-259. https://doi.org/10.2307/1907187
[11]
Field, C.B., Barros, V., Stocker, T.F. and Dahe, Q. (2012) Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation: Special Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Engalnd. https://doi.org/10.1017/CBO9781139177245
[12]
Coles, S., Bawa, J., Trenner, L. and Dorazio, P. (2001) An Introduction to Statistical Modeling of Extreme Values. Vol. 208, Springer, London, 208 p. https://doi.org/10.1007/978-1-4471-3675-0
[13]
Fisher, R.A. and Tippett, L.H.C. (April, 1928) Limiting Forms of the Frequency Distribution of the Largest or Smallest Member of a Sample. In Mathematical Proceedings of the Cambridge Philosophical Society. Vol. 24, Cambridge University Press, Engalnd, 180-190. https://doi.org/10.1017/S0305004100015681
[14]
Akaike, H. (1974) A New Look at the Statistical Model Identification. IEEE Transactions on Automatic Control, 19, 716-723. https://doi.org/10.1109/TAC.1974.1100705
[15]
Kim, H., Kim, S., Shin, H. and Heo, J.H. (2017) Appropriate Model Selection Methods for Nonstationary Generalized Extreme Value Models. Journal of Hydrology, 547, 557-574. https://doi.org/10.1016/j.jhydrol.2017.02.005
[16]
Mouhamed, L., Traore, S.B., Alhassane, A. and Sarr, B. (2013) Evolution of Some Observed Climate Extremes in the West African Sahel. Weather and Climate Extremes, 1, 19-25. https://doi.org/10.1016/j.wace.2013.07.005
[17]
Re, M. and Barros, V.R. (2009) Extreme Rainfalls in SE South America. Climatic Change, 96, 119-136. https://doi.org/10.1007/s10584-009-9619-x
[18]
Serinaldi, F. (2015) Dismissing Return Periods! Stochastic Environmental Research and Risk Assessment, 29, 1179-1189. https://doi.org/10.1007/s00477-014-0916-1
