5 Climate Change Impact on Hydrological Regimes …
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Table 3 Definition of Water-related disasters
Disaster subgroup Definition
Disaster main type
Meteorological
A hazard caused by short-lived, micro- to
meso-scale extreme weather and atmospheric
conditions that last from minutes to days
Extreme temperature storm
Hydrological
A hazard caused by the occurrence,
movement, and distribution of surface and
subsurface freshwater and saltwater
Flood landslide
Climatological
A hazard caused by long-lived, meso- to
macro-scale atmospheric processes ranging
from intra-seasonal to multi-decadal climate
variability
Drought wildfire
(Source The international Disaster Database (https://www.emdat.be/classification) of the Centre for
Research on the Epidemiology of Disasters (CRED)
4.1 Floods and Droughts
The frequency and magnitudes of both floods and droughts will be affected by climate
change as a result of changes in the intensity and frequency of rainfall. These events
cause considerable damages to life and infrastructure. Floods and droughts also
cause indirect adverse effects such as epidemics (Kundzewicz et al. 2008; Knox
et al. 2010). Floods due to tropical cyclones frequently affect Malawi, Mozambique
and Zimbabwe. Recent floods due to Cyclone Idai caused over a thousand deaths
and extensive damage to infrastructure particularly for rural communities and poor
urban households. Tropical cyclone activity in southern Africa has been recorded
with increased frequency in recent years causing massive damage and loss of life in
Mozambique, Zimbabwe, Zambia, Swaziland, South Africa, Madagascar and Mauritius (Reason and Keibel 2004; Klinman and Reason 2008) (Fig. 4 and Table 4).
Tadross et al. (2005) and New et al. (2006) showed evidence of changing rainfall
seasonality and extreme events. These observations ultimately, signify a significant
shift of climate variables from the recent past.
Droughts cause food insecurity and considerable damage to economic production
(Zinyowera and Unganai 1992; Kabat et al. 2002; Patt et al. 2008b; Tirado et al.
2010). For example, six warmest years on record for Zimbabwe occurred since 1987,
with corresponding increased frequency of droughts in southern Africa since 1990
causing massive drops in crop yields in Zimbabwe, Malawi and Zambia (Rouault
and Richard 2005; Manatsa et al. 2008; Gizaw and Gan 2017).
Figure 5 shows the trends in the occurrence of water-related disasters for selected
Southern African countries. What is evident is that the occurrence of droughts has
been increasing exponentially for the following countries: Lesotho, Malawi, Mozambique, South Africa and Madagascar (Fig. 5). Floods occurrence also exhibits the
same pattern as droughts as can be seen for South Africa, Zambia, Mozambique,
Malawi, Botswana and Angola. Recently, the region has been experiencing heat
waves and extensive wildfires, phenomena that had never been recorded in southern
111
Table 3 Definition of Water-related disasters
Disaster subgroup Definition
Disaster main type
Meteorological
A hazard caused by short-lived, micro- to
meso-scale extreme weather and atmospheric
conditions that last from minutes to days
Extreme temperature storm
Hydrological
A hazard caused by the occurrence,
movement, and distribution of surface and
subsurface freshwater and saltwater
Flood landslide
Climatological
A hazard caused by long-lived, meso- to
macro-scale atmospheric processes ranging
from intra-seasonal to multi-decadal climate
variability
Drought wildfire
(Source The international Disaster Database (https://www.emdat.be/classification) of the Centre for
Research on the Epidemiology of Disasters (CRED)
4.1 Floods and Droughts
The frequency and magnitudes of both floods and droughts will be affected by climate
change as a result of changes in the intensity and frequency of rainfall. These events
cause considerable damages to life and infrastructure. Floods and droughts also
cause indirect adverse effects such as epidemics (Kundzewicz et al. 2008; Knox
et al. 2010). Floods due to tropical cyclones frequently affect Malawi, Mozambique
and Zimbabwe. Recent floods due to Cyclone Idai caused over a thousand deaths
and extensive damage to infrastructure particularly for rural communities and poor
urban households. Tropical cyclone activity in southern Africa has been recorded
with increased frequency in recent years causing massive damage and loss of life in
Mozambique, Zimbabwe, Zambia, Swaziland, South Africa, Madagascar and Mauritius (Reason and Keibel 2004; Klinman and Reason 2008) (Fig. 4 and Table 4).
Tadross et al. (2005) and New et al. (2006) showed evidence of changing rainfall
seasonality and extreme events. These observations ultimately, signify a significant
shift of climate variables from the recent past.
Droughts cause food insecurity and considerable damage to economic production
(Zinyowera and Unganai 1992; Kabat et al. 2002; Patt et al. 2008b; Tirado et al.
2010). For example, six warmest years on record for Zimbabwe occurred since 1987,
with corresponding increased frequency of droughts in southern Africa since 1990
causing massive drops in crop yields in Zimbabwe, Malawi and Zambia (Rouault
and Richard 2005; Manatsa et al. 2008; Gizaw and Gan 2017).
Figure 5 shows the trends in the occurrence of water-related disasters for selected
Southern African countries. What is evident is that the occurrence of droughts has
been increasing exponentially for the following countries: Lesotho, Malawi, Mozambique, South Africa and Madagascar (Fig. 5). Floods occurrence also exhibits the
same pattern as droughts as can be seen for South Africa, Zambia, Mozambique,
Malawi, Botswana and Angola. Recently, the region has been experiencing heat
waves and extensive wildfires, phenomena that had never been recorded in southern