32
variability is also predicted to intensify (Intergovernmental Panel on Climate
Change 2014) and this might have stronger implications for RVF, given that the
intense precipitation which drives an RVF epidemic follows El Niño and La Niña
events in East and South Africa, respectively. Further evidence for an increased
precipitation under intermediate warming scenarios in parts of equatorial East
Africa is provided by Hulme et al. (2001). They suggest that the region will experience a 5–20% increase in rainfall between December and February and 5–10%
reduction in rainfall between June and August by 2050.
Climate change may indirectly increase RVF risk through land use change associated with the development of irrigation schemes and dams. The increasing frequency of droughts and erratic rainfall in arid and semi-arid areas would necessitate
the construction of dams and irrigation schemes to support water supply and food
production. Previously, outbreaks of RVF have been reported following flood irrigation in the Orange River region and Western Cape province, South Africa (Williams
et al. 2016), and the construction of dams, i.e. Aswan High Dam in Egypt in 1977
Fig. 3.2 Risk map for RVF in East Africa based on reported cases in livestock during the
2006/2007 outbreak and rainfall distribution (Bett et al. 2017). Probability estimates given on the
map indicate the chance that a given area could experience an RVF outbreak based on the environmental conditions observed in December 2006
B. Bett et al.
variability is also predicted to intensify (Intergovernmental Panel on Climate
Change 2014) and this might have stronger implications for RVF, given that the
intense precipitation which drives an RVF epidemic follows El Niño and La Niña
events in East and South Africa, respectively. Further evidence for an increased
precipitation under intermediate warming scenarios in parts of equatorial East
Africa is provided by Hulme et al. (2001). They suggest that the region will experience a 5–20% increase in rainfall between December and February and 5–10%
reduction in rainfall between June and August by 2050.
Climate change may indirectly increase RVF risk through land use change associated with the development of irrigation schemes and dams. The increasing frequency of droughts and erratic rainfall in arid and semi-arid areas would necessitate
the construction of dams and irrigation schemes to support water supply and food
production. Previously, outbreaks of RVF have been reported following flood irrigation in the Orange River region and Western Cape province, South Africa (Williams
et al. 2016), and the construction of dams, i.e. Aswan High Dam in Egypt in 1977
Fig. 3.2 Risk map for RVF in East Africa based on reported cases in livestock during the
2006/2007 outbreak and rainfall distribution (Bett et al. 2017). Probability estimates given on the
map indicate the chance that a given area could experience an RVF outbreak based on the environmental conditions observed in December 2006
B. Bett et al.