Late Pleistocene glaciers and climate in the High Atlas, North Africa

Author(s):  
Philip D. Hughes ◽  
David Fink ◽  
William J. Fletcher
2012 ◽  
Vol 12 ◽  
pp. 53-64 ◽  
Author(s):  
Laine Ann Clark-Balzan ◽  
Ian Candy ◽  
Jean-Luc Schwenninger ◽  
Abdeljalil Bouzouggar ◽  
Simon Blockley ◽  
...  

2014 ◽  
Vol 44 (2) ◽  
pp. 207-221 ◽  
Author(s):  
Rachid Ridouane

Berber (or Tamazight) is an Afro-Asiatic language spoken by an estimated 15–25 million in North Africa. It is mainly spoken in Morocco, Algeria, and by the Touareg population in Niger and Mali. Berber is also a native language of populations living in Libya, Tunisia and Egypt, though their numbers are less significant. Large Berber communities also live in Diasporas mainly in France, Spain, Holland, and Belgium. Three varieties of Berber are spoken in Morocco: Tarifit, spoken in northern Morocco, Tamazight, spoken in the Middle-Atlas, and Tashlhiyt, spoken in southern Morocco. Tashlhiyt, the variety presented here, is sufficiently homogeneous for all native speakers, who number an estimated 7–9 million, to communicate without difficulties (Stroomer 2008). There is nonetheless a measure of sub-dialectal variation, which affects mainly the way some stop consonants are produced. Three subsystems, corresponding roughly to three distinct geographical locations, can be identified: the ‘occlusive’ subsystem spoken in Agadir and its suburbs, the ‘fricative’ subsystem spoken mainly in the High-Atlas area, which spirantizes noncoronal obstruents /bkg/ in some contexts, and the ‘sibilant’ subsystem spoken in the Anti-Atlas area, where /t/ and /d/ are realized in some contexts as [s] and [z], respectively (Boukous 1994). This study is based on the speech of Tashlhiyt speakers who originate from Agadir. The text of ‘The North Wind and the Sun’ was read by a 27-year-old female speaker.


2016 ◽  
Author(s):  
Gonçalo Vieira ◽  
Carla Mora ◽  
Ali Faleh

Abstract. Relict and present-day periglacial activity have been reported in the literature for the upper reaches of the High Atlas mountains, the highest range in North Africa (Djebel Toubkal – 4,167 m a.s.l.). Lobate features in the Irhzer Ikbi South at 3,800 m a.s.l. have been previously interpreted as an active rock glacier, but no measurements of ground or air temperatures are known to exist for the area. In order to assess on the possible presence of permafrost, analyse data from June 2015 to June 2016 from two air temperature sites at 2,370 and 3,200 m a.s.l., and from four ground surface temperature (GST) sites at 3,200, 3,815, 3,980 and 4,160 m a.s.l. allowing to characterize conditions along an altitudinal gradient along the Oued Ihghyghaye valley to the summit of the Djebel Toubkal. GST were collected at 1-hour intervals and the presence of snow cover at the monitoring sites was validated using Landsat-8 and Sentinel-2 imagery. Two field visits allowed for logger installation and collection and for assessing the geomorphological features in the area. The results show that snow plays a major role on the thermal regime of the shallow ground, inducing important spatial variability. The lowest site at 3,210 m showed a regime characterized by frequent freeze-thaw cycles during the cold season but with a small number of days of snow. When snow sets, the ground remains isothermal at 0 °C and the thermal regime indicates the absence of permafrost. The highest sites at 3,980 and 4,160 m a.s.l. showed very frequent freeze-thaw cycles and a small influence of the snow cover on GST, reflecting the lack of snow accumulation due to the their wind-exposed settings in a ridge and in the summit plateau. The site located at 3,815 m in the Irhzer Ikbi South valley showed a stable thermal regime from December to March with GST varying from −4.5 to −6 °C, under a continuous snow cover. The site's location in a concave setting favours snow accumulation and lower incoming solar radiation due to the effect of a southwards ridge, favouring the maintenance of a thick snow pack. The stable and low GST are interpreted as a strong indicator of the probable presence of permafrost at this site, an interpretation which is supported by the presence of lobate and arcuate forms in the talus deposits. These results are still a first approach and observations through geophysics and boreholes are foreseen. This is the first time that probable permafrost is reported from temperature observations in the mountains of North Africa.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10504
Author(s):  
David M. Cooper ◽  
Andrew J. Dugmore ◽  
Andrew C. Kitchener ◽  
Marc J. Metzger ◽  
Antonio Trabucco

Aim We use ecological niche models and environmental stratification of palaeoclimate to reconstruct the changing range of the lion (Panthera leo) during the late Pleistocene and Holocene. Location The modern (early 21st century) range of the lion extends from southern Africa to the western Indian Subcontinent, yet through the 20th century this range has been drastically reduced in extent and become increasingly fragmented as a result of human impacts. Methods We use Global Environmental Stratification with MaxEnt ecological niche models to map environmental suitability of the lion under current and palaeoclimatic scenarios. By examining modelled lion range in terms of categorical environmental strata, we characterise suitable bioclimatic conditions for the lion in a descriptive manner. Results We find that lion habitat suitability has reduced throughout the Holocene, controlled by pluvial/interpluvial cycles. The aridification of the Sahara  6ka dramatically reduced lion range throughout North Africa. The association of Saharan aridification with the development of pastoralism and the growth of sedentary communities, who practised animal husbandry, would have placed additional and lasting anthropogenic pressures on the lion. Main Conclusions This research highlights the need to integrate the full effects of the fluctuating vegetation and desiccation of the Sahara into palaeoclimatic models, and provides a starting point for further continental-scale analyses of shifting faunal ranges through North Africa and the Near East during the Holocene. This scale of ecological niche modelling does not explain the current pattern of genetic variation in the lion, and we conclude that narrow but substantial physical barriers, such as rivers, have likely played a major role in population vicariance throughout the Late Pleistocene.


2017 ◽  
Vol 11 (4) ◽  
pp. 1691-1705 ◽  
Author(s):  
Gonçalo Vieira ◽  
Carla Mora ◽  
Ali Faleh

Abstract. Relict and present-day periglacial features have been reported in the literature for the upper reaches of the High Atlas mountains, which is the highest range in North Africa (Djebel Toubkal – 4167 m a.s.l.). A lobate feature in the Irhzer Ikhibi south at 3800 m a.s.l. has been previously interpreted as an active rock glacier, but no measurements of ground or air temperatures are known to exist for the area. In order to assess the possible presence of permafrost, we analyse data from June 2015 to June 2016 from two air temperature measurement sites at 2370 and 3210 m a.s.l. and from four ground surface temperature (GST) sites at 3220, 3815, 3980 and 4160 m a.s.l. to characterize conditions along an altitudinal gradient along the Oued Ihghyghaye valley to the summit of the Djebel Toubkal. GSTs were collected at 1 h intervals, and the presence of snow cover at the monitoring sites was validated using Landsat 8 and Sentinel-2 imagery. Two field visits allowed for logger installation and collection and for assessing the geomorphological features in the area. The results show that snow plays a major role on the thermal regime of the shallow ground, inducing important spatial variability. The lowest site at 3220 m had a thermal regime characterized by frequent freeze–thaw cycles during the cold season but with few days of snow. When snow settled, the ground surface remained isothermal at 0 °C , indicating the absence of permafrost. The highest sites at 3980 and 4160 m a.s.l. showed very frequent freeze–thaw cycles and a small influence of the snow cover on GST, reflecting the lack of snow accumulation due to the wind-exposed settings on a ridge and on the summit plateau. The site located at 3815 m in the Irhzer Ikhibi south valley had a cold, stable thermal regime with GST varying from −4.5 to −6 °C from December to March, under a continuous snow cover. The site's location in a concave setting favours wind-driven snow accumulation and lower incoming solar radiation due to the shading effect of a ridge, inducing the conservation of a thick snow pack. The stable and low GSTs are interpreted as a strong indicator of the probable presence of permafrost at this site, which is an interpretation supported by the presence of lobate and arcuate features in the talus deposits. We present first results and further observations using geophysics, and borehole measurements are foreseen. This is the first time that probable permafrost has been reported from temperature observations in the mountains of North Africa.


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