Members who attended the Western Cape Branch One-day lecture series on Climate Change on 28 August 2016 were interested in reading further on some of the issues, particularly the Milankovitch Cycles that summarise the periodic changes in the position of the Earth in relation to the Sun which affect the build-up or melting of polar ice caps. The following links are suggested, or you can Google the key words that interest you:

1.       Milankovitch Cycles and Glaciation http://www.indiana.edu/~geol105/images/gaia_chapter_4/milankovitch.htm
Milankovitch Cycles and Glaciation. The episodic nature of the Earth's glacial and interglacial periods within the present Ice Age (the last couple of million years) ...
 
2.       Milankovitch cycles - Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Milankovitch_cycles 
 Milankovitch theory describes the collective effects of changes in the Earth's movements upon ..... Subsequent research has shown that ice age cycles of the Quaternary glaciation over the last million years have been at a 100,000-year period, ...

For some further information on the evidence for climate change in southern Africa:

3. https://soundcloud.com/user-607757210/professor-richard-cowling-on-the-paleoscape-of-the-southern-cape
 
4. http://www.geology.uct.ac.za/prof/john/compton and www.johnscompton.com 
 
5.  http://www.pasthorizonspr.com/index.php/archives/06/2015/mapela-archaeologists-re-visit-a-forgotten-urban-site-in-zimbabwe