8 – Impacts

9 – Projections

The effects of climate change in South Africa are two-fold, human induced problems and natural catastrophes. The ongoing global temperature analysis by the NASA scientists at the Goddard Institute for Space Studies (GISS) project an increase of 2° to 4° Celsius in the average temperatures by the end of the century and greater irregularity in rainfall over Southern Africa (Climate Change Report, 2016). The Climate Systems Analysis Group & the IPCC have scientifically observed an overall warming in Johannesburg and based on the average of seven climate models project the annualised temperatures to increase by 2.4°C in near future and 4.5°C in the far future (Climate Change Report, 2016). The weather findings from the past years as part of the Fifth IPCC Assessment Report on Climate Change indicate an average increase of 0.6°C per decade in the minimum night-time temperatures in South Africa (IPCC, 2014). The escalating temperatures are projected to increase the annual rainfall by 18% by mid-century and an increase of 27% for the period 2081-2100 will bring about stronger floods and serves as prospective water-harvesting strategy. The assessment report uses a combination of GCM (Global climate model) and RCM (Regional climate model) to determine dominant climate trends and predict the future climate scenarios in South Africa.

The haphazard development in nexus with the dogmas of infinite growth have exacerbated the impacts of climate change. The repercussions of global warming are accentuated with widespread reduction in viable agriculture, food insecurity amongst economically marginalized groups, increased drought events, loss of biodiversity and displacement of livelihoods. In turn leads to distress migration from rural parts to cities.

Based on climate models, the city is forecasted to have significant higher temperatures, greater irregularity in rainfall with extreme events of thunderstorms and cloudbursts followed by long dry spells (Daniel K. Irurah, 2010).

2036-2065 2066-2095 2036-2065 2066-2095

Higher Projection Uncertainties.

Medium Projection Uncertainties.

Lower Projection Uncertainties.

FIG. 9.1 Annual mean temperature change (ºC) relative to 1976-2005, projected for 2036-2065 and 2066-2095 under conditions of the RCP 4.5 pathway (Source - South African weather service)

Higher Projection Uncertainties.

Medium Projection Uncertainties.

Lower Projection Uncertainties.

FIG. 9.2 Annual total rainfall change (mm per year) relative to 1976-2005, projected for 2036-2065 and 2066-2095 under conditions of the RCP 4.5 pathway (Source - South African weather service)

FIG. 9.3 Drought - frequent occurences due to semi-arid weather conditions and prologned dry season due to irregular rainfall patterns (Source -mzansiagritalk. com_archives_3108)

FIG. 9.4 Urban Floods - decrased surfacepermeability in combibation with torrential downpour by thunder storms. (Source - twitter.com_studentspaza)

FIG. 9.5 Water Scarcity- increased dry periods and extreme temperatures result in excessive evaporation rates. Thus, affecting water storage facilities and at the same time increases water demand leading to scarcity. (Source - Nic Bothma/ EPA) FIG. 9.6 Food insecurity- the drought can result in inadequate recharge of groundwater and limited municipal water supply to agriculture sector might hamper food production cycles in the region (Source - Waldo Swiegers/ Bloomberg).

FIG. 9.7 Increase in Power Demand - More than 85% of the electricity is generated by coal-powered thermal stations in Mpumalanga. FIG. 9.8 Land Subsidence - The depletion of groundwater table by borewell irrigation leads to the formation of sink holes (Source - Council of GeoScience)

FIG. 9.9 Urban Heat Islands and heatwave - With rapid urbanisation, the paved surfaces retain direct heat energy leading to pockets of heightened microtemperatures. (Source - Nic Bothma/EPA)

FIG. 9.10 Health hazards - Heavy rainfall events and frequent flooding results in unsanitary conditions and disease outbreaks (Source - IFRC, Denis Onyodi).