South Africa’s geographic location results in an annual seasonal temperature cycle that peaks in the austral summer during January (30°C), and reaches a minimum during July (-2°C). Average annual rainfall is about 460 mm, but rainfall amount is lowest in the arid north-west, and increases southwards. South Africa’s mean annual rainfall ranges from less than 100 mm in the north-west to almost 1,200mm over the east and on the southern margins (Second National Communication, 2011). Key historical climate trends are summarized below:
- From 1961 to 2000, the occurrence of extreme cold days and nights has decreased by 3.7 and 6.0 days/ nights per decade, respectively, and the occurrence of extreme hot days and nights has increased by 8.2 and 8.6 days/nights per decade, respectively;
- Warming trends are more obvious over the western interior, western and southern coastal regions, and less so over the central interior. Almost 90% of the stations recorded positive annual mean maximum temperature trends.
- Rainfall variability is high over much of the country, though somewhat lower in the winter rainfall zones of the west;
- Annual rainfall has shown no consistent trends across the southern African region, but there have been statistically significant increases in daily rainfall intensity and dry spell duration over the region;
- There is some evidence for statistically significant increases in precipitation since the 1950s observed in the south-west of South Africa, and significant decreases in the north-east.
This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.