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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.
... 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.
... According to the ages of segments CH-3'e, CH-3'd and CH-3'c, stem 3 had grown almost twice as fast (i.e., 0.20 m; from 0.85 to 0.65 m) in 68 years (1243-1311; 0.294 × 10 −2 m year −1 ) and another 0.20 m (from 0.65 to 0.45 m) in 83 years (1311-1394; 0.241 × 10 −2 m year −1 ). These growth rates and periods may be associated with the Medieval Warm Period in southern Africa (from around 900 to 1300-1400), which was warmer and wetter than the present climate [26]. Around 1400-1500, the growth rate of stem 3 decreased considerably. ...
... In this period, the climate shifted from wetter to drier conditions and the Little Ice Age, which was cold and dry, had begun in southern Africa (from ca. 1400-1500 to 1800) [26]. The slowing of growth continued with the cooling of the climate, culminating with the Maunder minimum (1690-1740 in southern Africa [25,27]). ...
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The year 2016 witnessed the fall of a symbol of the botanical world: the historic Chapman baobab of Botswana. This article presents the results of our investigation of the standing and fallen tree. The Chapman baobab had an open ring-shaped structure composed of six partially fused stems. Several wood samples collected from the stems prior and after their collapse were analysed by using radiocarbon dating. The radiocarbon date of the oldest sample was 1381 ± 22 BP, which corresponds to a calibrated age of 1345 (+10, −15) calendar years. The dating results show that the six stems of the Chapman baobab belonged to three different generations, which were 1350–1400, 800–1000 and 500–600 years old. The growth rate variation of the largest and oldest stem is presented and correlated with the climate evolution in the area over the past 1000 years. The factors that determined the sudden fall and death of the Chapman baobab are also presented and discussed.
... 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. ...
Article
South Africa has a particularly spatially heterogeneous climate driven by a complex set of ocean-atmospheric factors. This results in three distinct regions of rainfall seasonality: the summer-(SRZ), winter-(WRZ) and year-round (YRZ) rainfall zones. Even within these zones there is considerable spatio-temporal variability in precipitation patterns, especially in the SRZ which covers the largest terrestrial area. Over the past several thousand years the position of the boundaries of the southern extent of the SRZ have shifted due to the influences of major climate systems, as well as changes in the characteristics of the adjacent oceanic currents. Here we use the Modern Analogue Technique on a new synthesis of pollen records from across the SRZ to quantitatively reconstruct four climate variables (Mean Temperature of the Coldest month, Mean Temperature of the Warmest Month, Mean Summer Precipitation and Winter Climatic Moisture Index), over the past 36,000 years. The climate variables and number of analogues used were selected after thorough examination of the modern dataset. The results provide evidence for three key features: first, an early deglaciation following a cold, dry and prolonged Last Glacial Maximum. Second, a clear manifestation of the African Humid Period in the northeastern part of the zone, supported by reconstructed sea surface temperatures. And third, a short-lived cold period at around 10 cal kyr BP, which may have been obscured by larger statistical errors in past studies. As it is still mostly within the margin of error for our study, this period requires further study. Our results show that the technique can be used successfully on large and diverse compilations of South African records, improving comparability with other regions.
... Three dates as early as AD 1000-1100 match the Medieval Warm Period (MWP, Lamb 1965), also called the Medieval Climate Anomaly (MCA, Xoplaki et al. 2011). This occurred at around AD 900-1300 in the Northern Hemisphere, confirmed for the Southern Hemisphere by Tyson & Lindesay (1992), Tyson et al. (2000), Mayewski et al. (2015), amongst others. All these three profiles show continuous LIA sedimentation up to AD 1700, in line with our prior investigations concerning the strong influence of solar irradiation. ...
Article
Dryland slopes, fluvial fans and terraces are recognized as highly sensitive process-response systems and important geoarchives for the reconstruction of palaeoclimatic driven landscape development in Southern Africa. The aim of this study is to study a dryland drainage system with a clearly limited regional catchment area, whose drainage and sedimentation behavior is unaffected by distant meteorological events or changes in climatic outside the region. Our results highlight for the first time the widespread occurrence of fluvial and lacustrine sediments in the Naukluft Mts. foreland as part of the Great Escarpment and their potential as Late Quaternary geoarchives. The region's special interest and overarching value lies (i) in the bounded catchments of both the lacustrine BüllsPort Playa and the ephemeral rivers Tsauchab and Tsondab within the South African Great Escarpment and (ii) in the rivers' endorheic character and dead ends within the Namib Sand Sea to the West. All these lacustrine and fluvial systems first and foremost exclude supra-regional influences within the flow regime. Uniquely, the key palaeocli-matic question of periodical shifts of the rainfall zones during Holocene and Late Glacial times can be studied in both these catchments. This study also combines new data from the semi-desert environment of the Naukluft Mts. with data from the terminus sites Sossusvlei and Tsondabvlei within the Namib dunes. From our interpretation of the desert flash flood series, the drainage history from pre-LGM times within MIS 3 up to modern times is represented in our data. The Late Termination I was the period with the highest flow rates post MIS3, raising the Urikos Terrace. This must have been caused by strong monsoonal rainfall events from summer TTT, giving rise to extreme flash floods. Little Ice Age sediments have filled the entire thalweg, with the exception of remnant Holocene to MIS 3 terraces to the sides and provide a unique framework for ecological conditions.
... Therefore, it was originally thought that the LIA mainly, or only, impacted the mid-to high-latitudes (Lane et al., 2011), and consequently the populations living in those areas. Nonetheless, climatic perturbations contemporaneous to the LIA were also recorded at low latitudes in the Caribbean Islands (Lane et al., 2011), in South America (Brown and Johnson, 2005), in equatorial Africa (Verschuren et al., 2000;Russell et al., 2007), in East Africa (Russell et al., 2007), in tropical southeast Africa (Johnson et al., 2001;Brown and Jonhson, 2005), in South Africa (Huffman, 1996;Tyson et al., 2000;Holmgren et al., 2001) Table 1). ...
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The hard and soft tissue remains of a pre-Hispanic population of the Gran Canaria Island at six different archaeological localities were studied using 14C dating and stable isotope compositions. Radiocarbon dating indicates island occupation ranging from the beginning of the 7th to the mid-14th century. We analyzed the oxygen isotope compositions of apatite phosphate bones of some pre-Hispanic individuals. The oxygen isotope compositions of meteoric water (δ18Ow) show a significant decrease from − 2.1 ± 1.5 to − 4.4 ± 1.2‰ (VSMOW) from the Medieval Warm Period (MWP) to the Little Ice Age (LIA). This is interpreted to reflect a decrease in air temperature by about 5 ± 3 ◦C. Archaeological data along with δ13C, δ15N and δ34S values of soft tissue indicate that the pre-Hispanic population from Gran Canaria relied on agriculture throughout the 7th to mid-14th cen- tury. However, a significant contribution of seafood to the diet of the pre-Hispanic population is observed at archaeological sites located close to the shore. These results suggest cultural resilience in the pre-Hispanic population of Gran Canaria, reflected in the relative constancy of their diet in light of climate change.
... We propose that environmental conditions could be one of the factors to explain this late presence of domesticates at Leopard Cave. Indeed, several authors have argued that the medieval warm period (occurring before the Little Ice Age) may have favoured increased precipitation in southern Africa between 1000 and 700 BP [75][76][77] . Wetter conditions may have created watering holes and improved grazing land availability and, thus, better environmental conditions for the management of livestock in the Namib region, particularly within each of the three inselbergs of Brandberg, Spitzkoppe, and Erongo. ...
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The advent of domestication is a major step that transformed the subsistence strategies of past human societies. In Africa, domestic caprines (sheep and goat) were introduced in the northeastern part of the continent from the Near East more than 9000 years ago. However, their diffusion southwards was slow. They are thought to have made their first appearance in the southern part of the continent ca. 2000 years ago, at a few Later Stone Age sites, including Leopard Cave (Erongo region, Namibia), which provided the oldest directly dated remains assigned to sheep or goat on the basis of morphology of bones and teeth. However, similarities in morphology, not only between these two domesticated caprine species, but also between them and the small wild antelopes, raised questions about the morphological species attribution of these remains. Additionally, the high fragmentation of the site's osteological remains makes it difficult to achieve species-level taxonomic identification by comparative anatomy. In this paper, we report molecular species identification of the Leopard Cave remains using palaeoproteomics, a method that uses protein markers in bone and tooth collagen to achieve taxonomic identification of archaeological remains. We also report new direct radiocarbon dates. Wild antelope remains from museum collections were used to enrich the available protein record and propose de novo type I collagen sequences. Our results demonstrate that the remains morphologically described as domesticates actually belong to a wild antelope species and that domestic caprines first appeared at Leopard Cave 1500 years later than previously thought. This study illustrates that the use of palaeoproteomics coupled with direct radiocarbon dates is particularly suited to complement classic zooarchaeological studies, in this case concerning the arrival of the first herding practices in arid environments.
... Foden et al. [41] showed that the temperature increase in Namibia during the last two or three decades is roughly three times more than the global mean temperature increase reported for the 20th century. Several authors [42][43][44] showed that drastic temperature increases and drier conditions were present in southern Africa on a number of occasions during the last few centuries. It is further proposed that the decomposition of the dead plants altered the chemical properties of the sand which manifested in the hydrophobicity of FC soil. ...
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