![]() ![]() ![]() Célérier and Charton ( 1922) and De Martonne ( 1924) reported glacial deposits in the headwaters of the Imenane and Rheraia (or Rhéraya) Valleys on the northern slopes of the Toubkal massif. 199) noted that ‘ there is undoubted evidence of a Glacial period in the later history of the mountains, in the shape of moraine-heaps and ice-worn rocks and boulders in their glens and valleys’. 205) was sceptical of some of Maw’s glacial interpretations. Maw (1878) wrote a geological appendix in Hooker and Ball’s ( 1878) book ‘ Journal of a tour in Marocco and the Great Atlas’. Some of the earliest observations of glacial features in the Atlas Mountains were reported by Hooker and Ball ( 1878). In 77 AD, Pliny the Elder described them as the “the most fabulous Mountains of Africa” and recalled the observations of Suetonius Paulinus, the first Roman commander to cross the Atlas, of an unknown summit as “covered with deep snowdrifts, even in summer” (Pliny translated in Rackham 1942, p. The Atlas Mountains contain the highest peaks of North Africa. A particular focus of this research is to utilise geomorphological and geochronological evidence to understand fluctuations in snow and ice through the Holocene and link this to continuous records of environmental change in the High Atlas region. A new research programme is underway investigating the history of late-lying snow and cirque glaciers in the High Atlas. However, inter-annual changes in snowpack mass balance are affected by very large variations (> 400% variability) in winter precipitation. The disappearance of many perennial snowpatches in the last few decades coincides with a strong trend towards warmer summer air temperatures since the 1970s (> 2 ☌). In addition to strong shading, many of the current late-lying snowpatches are fed by long deep gullies which funnel avalanching snow from the cirque backwalls. ![]() The niche glaciers and late-lying snowpatches survived below the regional equilibrium line altitude because of strong local topoclimatic controls. These landforms most likely record the positions of former niche glaciers and late-lying snowpatches in the Little Ice Age. Coarse sediment ridges interpreted as moraines or pronival ramparts enclose most of these snowpatches. Many other sites also support non-perennial late-lying snow below steep shaded north and northeast-facing cliffs at altitudes > 3100 m. However, there is evidence that niche glaciers and late-lying snowpatches in the High Atlas were present as recently as the last century and there are at least four sites where snowpatches appear to survive some summer seasons today. There are no glaciers today in the High Atlas, Morocco. ![]()
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