Burkina Faso - Hazards and risks
The vulnerability of West African countries such as Burkina Faso is likely to increase as demand on natural resources continue to rise in association with a rapidly growing population. Global climate change and its impact on the environment will contribute to aggravating this situation. Climate projections for the region indicate increasing weather extremes. The disaster management agencies in the region have to adapt to the increasing number of natural disasters, ranging between the extremes of drought and flood. Secondary impacts triggered by environmental conditions, such as locust plagues, additionally deteriorate the living conditions and food security of the local population. Especially in climate sensitive regions, where rain-fed and irrigated agriculture is the main source of food security and income, concerns about the variability in rainfall, its temporal and spatial distribution, must be taken very seriously. This seems to be particularly true of West Africa where e.g. the causes of the great Sahelian drought of the early 1970s and 1980s bear evidence of the regions proneness to this particular hazard1. The most pronounced dry years were 1973, 1984, 1991,1994, 1998, and 2004. Fig. 1: West/Central Sahel Rainfall 1950-2004 (as standardized deviations from base period: 1950-1990) Source: IMPETUS Atlas 2007 Droughts and floods – both weather extremes have serious impact on the natural vegetation as well as on agriculture and livestock rearing: substantial losses in yield and cattle (20 – 30 %) resulting in food insecurity, population migration, and lowering of the groundwater table. Especially during the last two decades the number of inundations increased within the Sahel area. In Burkina Faso the following floods have been observed:
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Another important aspect within Burkina Faso is the appearance of vector borne diseases and epidemics of weather- and climate-sensitive infectious diseases, including malaria, meningitis, and cholera, which cause massive disruption to societies and overburden national health systems. Whereas malaria has to be regarded as a more or less permanently existing disease within the region the occurrence of meningitis has a seasonal character and is obviously related to climatic conditions and the influence of the so-called ‘harmattan’, a very dry wind blowing to the Sahelian region from NE (central Sahara). Especially during the dry season from November to March the weather conditions are characterized by high daytime temperatures (33 to >40 °C), rather cool nights (10 to 15 °C), and occasionally very low relative humidity (<10%). The most devastating epidemics of meningitis were recorded in 1996 and 1997 when altogether more than 42,000 persons were affected with about 4,000 cases of death. Cholera, on the other hand, is an epidemic disease which is related to the rainy season. Due to the South-North motion of the sun during the first half of each year the inter-tropical convergence zone (ITCZ) moves from its position near the equator pole-ward to higher latitudes on the northern hemisphere. In consequence, from April/May to October the whole area of West Africa is getting under the influence of the moisture-laden south-west monsoon. This humid air stream blowing from the Gulf of Guinea is responsible for about 90% of the annual rainfall. In the case of regional floods, the impact of cholera is aggravated by the inundation of sanitary facilities within villages and cities. Finally, the impact of humanitarian crisis has to be mentioned. As one major incident the civil war in Cote d’Ivoire in 2002 caused a population movement due to socio-political turmoil. In order to help Burkinabe return to their country, on 19 November 2002 the Government launched the ‘Operation Bayiri’ (return to the homeland). This initiative was also supported by various contributions from individuals, private companies, international institutions and NGOs with donations of medicines, food, clothes, etc, as well as money. According to official numbers from the Government in Burkina Faso altogether 366,000 persons returned to their home country. This crisis also seriously affected the economy of Burkina Faso, especially the cotton sector, as the border between Burkina Faso and Cote d'Ivoire was closed in 2002, effectively cutting off cotton exporters from their main port of export Abidjan.
- 1. Understanding the reasons for the significant alterations in Sahelian rainfall is still a major challenge for scientific research, since drought and, as in recent years increasingly experienced the occurrence of floods, affect great parts of West Africa in terms of ecological, economic, and societal aspects. The spectra of hitherto existing hypotheses includes those focussing on global oceanic-atmospheric circulation patterns, the influence of land cover changes, and effects due to changes in atmospheric composition, i.e. aerosol concentrations as well as greenhouse gas and sulphate aerosol emissions. However, these issues still remain unresolved. Although inter-seasonal and inter-annual variability in precipitation in part has been successfully forecasted for West Africa, there is still a lack of knowledge in predicting climate changes on decadal or notably multi-decadal timescales. In addition, results from General Circulation Models (GCM), as often applied in frame of the above mentioned publications, are essential to understand large-scale coherences, but do not necessarily match the requirements of regionally to locally orientated approaches.