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The Little Ice Age and medieval warming in South Africa

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The Little Ice Age in South Africa, from around AD 1300 to 1800, and medieval warming, from before 1000 to around 1300, are shown to be distinctive features of the regional climate of the last millennium. The proxy climate record has been constituted from oxygen and carbon isotope and colour density data obtained from a well-dated stalagmite derived from Cold Air Cave in the Makapansgat Valley. The climate of the interior of South Africa was around 1°C cooler in the Little Ice Age and may have been over 3°C higher than at present during the extremes of the medieval warm period. It was variable throughout the millennium, but considerably more so during the warming of the eleventh to thirteenth centuries. Extreme events in the record show distinct teleconnections with similar events in other parts of the world, in both the northern and southern hemispheres. The lowest temperature events recorded during the Little Ice Age in South Africa are coeval with the Maunder and Sporer Minima in solar irradiance. The medieval warming is shown to have coincided with the cosmogenic 10Be and 14C isotopic maxima recorded in tree rings elsewhere in the world during the Medieval Maximum in solar radiation.
... The temperature of the last millennium in southern Africa was characterised by positive anomalies during MWP, after which a variable, unstable and mostly cold climate prevailed during 1300-1850, corresponding to the LIA [90,91]. The temperatures for southern Africa over the last millennium were about 3 • C higher during MWP or about −1 • C lower during LIA, compared to the present day [91]. ...
... The temperature of the last millennium in southern Africa was characterised by positive anomalies during MWP, after which a variable, unstable and mostly cold climate prevailed during 1300-1850, corresponding to the LIA [90,91]. The temperatures for southern Africa over the last millennium were about 3 • C higher during MWP or about −1 • C lower during LIA, compared to the present day [91]. The very cold periods reported by Tyson and Lindsey [90] around 1600 and 1700 CE are replicated in the Chapman archive as years with lower rainfall. ...
... The very cold periods reported by Tyson and Lindsey [90] around 1600 and 1700 CE are replicated in the Chapman archive as years with lower rainfall. Tyson et al. [91] established that LIA had two mainly dry periods in 1300-1500 and 1675-1800 CE, alternating with a warmer period in 1500-1675 CE. Although a long dry period is evinced by the isotopic excursions between 1288 and 1306 CE, the wettest conditions were registered in the time frame 1379-1446. ...
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A high-resolution climate archive was reconstructed based on carbon isotope analysis and radiocarbon dating of the Chapman baobab in northeastern Botswana. The Chapman baobab, which exhibited an open ring-shaped structure composed of six stems, collapsed in January 2016 during an intense El Niño event. Two samples belonging to the oldest stems were investigated in order to obtain a proxy rainfall record, which provides insight into the precipitation regime over the last millennium, evincing centennial and decadal scale variability. The results indicate that the Medieval Warm Period was marked by relatively stable precipitation, whereas rainfall variability and drought frequency increased during the Little Ice Age. The investigated area has experienced both wetter and drier conditions in the past. The wettest conditions of the last millennium were registered before 1450 while the driest period occurred in 1835. For southern Africa, inter-annual rainfall variability is mainly associated with sea surface temperatures in the Agulhas Current core region, which determine the east–west displacement of tropical temperate troughs. Previous studies suggested that positive sea surface temperature anomalies in the Mozambique Channel led to an eastward movement of the troughs but the Chapman record demonstrates a westward displacement in the past, causing drought in northeastern South Africa and wetter conditions in the central part of southern Africa. The positive rainfall correlation with SST anomalies reversed after 1900, causing a gradual decrease in precipitation and confirming the current aridity trend for Botswana. The results contribute to a better understanding of the past climate of southern Africa for which paleoclimate reconstructions remain scarce.
... Parkington 1987;Jerardino et al. 2016Jerardino et al. , 2018Rick et al. 2020). Among the latter, is the locally under-studied period known as the Medieval Warm Anomaly (MWA) or Medieval Warm Epoch ( c. 1300-650 calibrated years Before Present [cal BP]), characterised by hot and dry local conditions (Tyson et al. 2000;Chase & Meadows 2007;see below). ...
... The first two Neoglacial events c. 4200 cal BP and between c. 2500 and 1800 cal BP also coincided with atmospheric and sea surface cooling phases which probably brought more rain to the central west coast (Cohen et al. 1992;Compton 2001). The MWA, a warm and dry period, with apparently warmer sea surface temperatures and a~0.5 m sea level highstand followed thereafter around 1300-650 cal BP (or AD 800-1400) (Cohen et al. 1992;Tyson et al. 2000;Compton 2001Compton , 2006Chase & Meadows 2007). MWA would have meant frequent droughts or reduced precipitation in Elands Bay, perhaps similar to current rainfall levels further north in Namaqualand. ...
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Spring Cave is situated just below the Baboon Point escarpment in Elands Bay and is one of only a handful of central west coast sites with deposits dating to the Medieval Warm Anomaly (MWA, c. 1300-650 cal BP). This was a climatological period of global significance that brought hot and dry conditions to much of the South African west coast, an ecologically stressed period affecting people, animals and plants alike. Although Spring Cave also dates to before and after the MWA, a large amount of its deposits date to this period. Earlier research on the central west coast has shown that most MWA-dated sites are situated at high elevations and near the coast, and that such placement in the landscape allowed monitoring of the movement of game, predators, and groups of people with or without livestock. High mobility, seeking safety and shelter at higher elevations, and a close watch on the landscape were part of general adaptive strategies, but people at Spring Cave may have added repeated ritual slaughter of small carnivores to the range of coping mechanisms. Doing so, according to ethno-historical records among herding groups, would have brought good luck and well-being. When considering Spring Cave's entire sequence, broad late Holocene regional patterns are also confirmed: i) higher frequencies of exotic lithic raw materials before 3000 cal BP; and ii) greater emphasis on gathering limpets after 2000 BP, while mussels dominate assemblages before then. Moreover, metrical data on limpets, mussels and Cape rock lobster suggest that these species were not processed before their transport back to the cave, an observation at variance with barnacles and fish.
... Paleoclimatic records for the regionbased on oxygen, nitrogen and carbon isotopesshow that the rainfall and temperature varied between AD 900 and the present (e.g., Smith et al. 2007Smith et al. , 2010Woodborne et al. 2015). These isotopic analyses indicate that, during the Little Ice Age (AD 1300-1800; Tyson et al. 2000), there was a ±1.4°C decrease in temperature accompanied by a decrease in rainfall (Woodborne et al. 2015). The SLCA also plays host to several different environment types including woodland in the form of a riparian forest, rocky hills, and grasslands (e.g., Eastwood & Blundell 1999;Plug 2000;Rutherford et al. 2010). ...
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Rain-control in the Shashe-Limpopo Confluence Area (SLCA) is one sphere in which hunter-gatherer and farmer interaction is archaeologically visible. One avenue of examining this interaction is through faunal analysis. This paper presents an updated taxa list for one of the identified rain-control sites in the SLCA-Ratho Kroonkop. By identifying the taxa accumulated at Ratho Kroonkop and contextualising them using radiocarbon dates and relevant ethnographies, we were able to determine that particular animals were significant to the people who utilised the location as a rain-control site. Additionally, we were able to establish that this significance continued from the K2 period (AD 1000-1220) to the historic period.
... Post glacial climatic cycles, described above, are stabilized at this time i.e. the last 2000 years, although a hot dry period known as the Medieval Warm Anomaly (MWA) or Medieval Warm Epoch (c. 1300-650 cal BP) does appear to impact local conditions (Tyson et al. 2000;Jerardino et al 2021). Peter Mitchell draws attention to: "El Niño events [that] usefully remind us of the value of situating southern Africa history within a global environmental context" (Mitchell 2017: 46). ...
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This research investigates the density and distribution of quartz deposited over an area measuring 70,000m2 at the Kurukop in the Nama Karoo, South Africa. My interest was in the quartz artefacts and a possible relationship with engraved depictions, water features and “rubbed” surface abrasions. To investigate this I used a combination of techniques. These include the GIS capability available in Google Earth Pro, primarily to measure and quantify areas, distances and elevations. To improve resolution and measurement accuracy a composite drone image of the entire site was photographed and imported into the Google Earth application. Quartz samples from two squares (SA1, SA2) were collected, counted and weighed, and this data was intercalated with measurements provided by the aerial map and a detailed ground survey. A number of trends can be observed, indicating that the remains of previous activities probably influenced subsequent decisions. A rhythmanalysis is applied to the ethnoarchaeological dimensions of the study and from this perspective the production of space at the Kurukop is considered. The conclusion I draw is that the presence of water appears to have influenced the way in which people chose to interact with and mark the site. Key words: quartz, petroglyphs, landscape, rhythmanalysis, spatial mapping, aerial photography
... For the late Holocene, there is evidence for a neoglacial period at around 2 ka for large parts of the country (Rosen et al., 1999;Holmgren et al., 2003;Scott et al., 2003a;Mulder and Grab, 2009). In addition, multiple studies have suggested that climatic events centred around the North Atlantic may also have manifested in southern Africa, such as the Younger Dryas (Abell and Plug, 2000;Gasse et al., 2008;Chase et al., 2015), the so-called "8.2 ka event" Voarintsoa et al., 2019), the Medieval Climatic Anomaly and the Little Ice Age (Tyson et al., 2000;Norström et al., 2018;Du Plessis et al., 2020;Hahn et al., 2021), although there is some contention at least regarding the Younger Dryas . This paper will examine the palaeoclimate dynamics within the SRZ through the use of quantitative climate reconstructions using published pollen records from across the region. ...
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