Glacial and Periglacial Environments
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The University of Manchester Research Glacial and Periglacial Environments Link to publication record in Manchester Research Explorer Citation for published version (APA): Hughes, P. D., & Woodward, J. C. (Ed.) (2009). Glacial and Periglacial Environments. In The Physical Geography of the Mediterranean Basin (1st ed., pp. 353-383). Oxford University Press. Published in: The Physical Geography of the Mediterranean Basin Citing this paper Please note that where the full-text provided on Manchester Research Explorer is the Author Accepted Manuscript or Proof version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version. 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Oct. 2021 12-Woodward-C12 9780199268030-Jamie-Woodward (Typeset by SPi, Chennai) 353 of 384 April 15, 2009 13:21 12 Glacial and Periglacial Environments Philip Hughes and Jamie Woodward Introduction are most clearly evident in the Mediterranean moun- Traditionally, glacial and periglacial geomorphology has tains where the erosional and depositional legacy is not featured prominently in discussions about the phys- frequently well preserved. Cirques, glacial lakes, ice- ical geography of the Mediterranean basin. It is now scoured valleys, moraines, pronival ramparts, relict clear, however, that on numerous occasions during the rock glaciers, and other glacial and periglacial fea- Pleistocene, and to a lesser extent during the Little Ice tures can be found in many Mediterranean moun- Age (LIA), glacial and periglacial activity was wide- tain ranges (Hughes et al. 2006a). Upland limestone spread in many of the region’s mountain ranges (Hughes terrains are widespread across the Mediterranean and et al. 2006a; Hughes and Woodward 2008). Even today, many of these landscapes have been shaped by a com- small glaciers and active periglacial features can be bination of glacial and karstic processes (Chapter 10). found on the highest peaks. Many mountain landscapes In fact, glacio-karst is probably the dominant land- in the Mediterranean basin are therefore the product scape in many mountain regions, including the Dinaric of glacial and periglacial processes that have fluctu- Alps of Croatia/Bosnia/Montenegro (Nicod 1968), the ated in intensity and spatial extent through the Quater- Cantabrian Mountains of Spain (Smart 1986) and nary. Glacial processes are defined here as those occur- the Pindus Mountains of Greece (Waltham 1978; ring as a result of dynamic glacier ice. The periglacial Woodward et al. 2004; Hughes et al. 2006b). Glaciated zone is sometimes defined as non-glacial areas where mountain landscapes are also found in other rock the mean annual temperature is less than 3◦C (French types including granite (e.g. Monte Cinto, Corsica) 1996: 20). However, cryogenic processes can be impor- (Conchon 1978) and ophiolite (e.g. Mount Smolikas, tant in landform development, even in areas of shallow Greece) (Hughes et al.2006c). frost over a wide range of mean annual temperatures. Glacial and periglacial landforms provide an impor- Thus, the term ‘periglacial’ is applied here to areas char- tant record of environmental change and can be used acterized by cold-climate processes—where frost and to reconstruct past glacial climates. This chapter exam- nival processes are important—but where glaciers are ines the evidence for both past and present glacial absent. and periglacial activity in the Mediterranean moun- Glacial and periglacial processes in the uplands can tains and assesses its wider significance in the region. exert considerable influence upon geomorphological All the sites referred to in this chapter are shown in systems at lower elevations. Fluvial systems, for exam- Figure 12.1 and all elevations are given in metres above ple, over a range of timescales have been shown to sea level. This chapter is divided into three main parts. be especially sensitive to changes in sediment supply These consider, in turn, glacial and periglacial envi- and water discharge from glaciated mountain headwa- ronments of the present, during the Holocene (with ters (Gurnell and Clark 1987; Woodward et al. 2008). emphasis on the LIA), and during the cold stages of the Nonetheless, the geomorphological impacts of glaciation Pleistocene. 12-Woodward-C12 9780199268030-Jamie-Woodward (Typeset by SPi, Chennai) 354 of 384 April 15, 2009 13:21 354 Philip Hughes and Jamie Woodward 13 3 4 2 9 8 1 6 5 14 10 11 18 22 16 7 15 21 20 12 19 25 26 24 17 27 23 11 Currently glacierized areas 0 1000 km 1 Other mountain areas 1 Serra da Estrela 7 Sierra Nevada 13 Julian Alps 19 Western Taurus 25 Djurdjura Massif 2 Serra do Gêres 8 Pyrenees 14 Dinaric Alps 20 Central Taurus 26 Middle Atlas 3 Serra de Queixa 9 Alpes Maritimes 15 Pindus Mountains 21 Eastern Taurus 27 High Atlas 4 Cantabrian Mountains 10 Corsica 16 Mount Olympus 22 Pontic Mountains 5 Sierra de Gredos 11 Italian Apennines 17 Crete 23 Jbel Liban 6 Peñalara Massif 12 Mount Etna 18 Pirin/Rila Mountains 24 Aurès Massif Fig. 12.1. Map of the Mediterranean showing the main mountain areas referred to in this chapter. Currently glacierized areas are indicated. Modern Glacial and Periglacial TABLE 12.1. Modern glaciers in the Mediterranean Environments Mountain area Number Total ELA (m) Maximum of glacier glacier Modern glaciers are rare in the Mediterranean because glaciers area length most mountains do not reach the snowline. Glaciers are (km2) (km) present, however, under modern climatic conditions in Pyrenees 41 11.43 2,320–3,005 2.0 the Pyrenees, Alpes Maritimes, Italian Apennines, Julian Alpes Maritimes 6 0.31 2,800 <0.5 Alps, and in the mountains of Montenegro and Turkey Apennines 1 0.045 2,750 0.4 . < . (Table 12.1 and Figure 12.1). These glaciers are mainly Julian Alps 1 0 0303 2,500 0 5 Turkey 40+ 22.9 2,900–4,100 4.0 small cirque glaciers on mountains above 2,500 m, but Montenegro 1 0.05 2,150 <0.5 extensive valley glaciers and small ice caps are present Sources: Based on data provided in Serrat and Ventura (1993), J. M. on some of the highest mountains (>4,000 m). Grove (2004), Gellatly et al. (1994), Gabrovec (1998), Çiner (2004), Kurter and Periglacial processes are much more widespread and Sungur (1980), and Hughes (2007). are active above 2,000 m in areas as far south as the Moroccan Atlas and at lower elevations in the northern Mediterranean. Snowfall is heavy in many of the Mediter- ranean mountains with most falling during the winter glaciers occur in the mountains of eastern Turkey months between November and March (Chapter 3). (Akçar and Schlüchter 2005). The presence of glaciers in these mountains was noted in the nineteenth century by Ainsworth (1842) and Palgrave (1872). In 1980, Turkey glaciers covered a total area of c.22.9 km2 (Kurter and Thirty-eight modern glaciers have been identified in the Sungur 1980), although almost everywhere glaciers mountains of Turkey and the largest Mediterranean are in retreat (Çiner 2004). Periglacial activity is also 12-Woodward-C12 9780199268030-Jamie-Woodward (Typeset by SPi, Chennai) 355 of 384 April 15, 2009 13:21 Glacial and Periglacial Environments 355 likely to be a major influence on modern landform snow, firn, and ice has been reported from this site in a development in these areas, but its effects have not been deep karstic shaft at c.3,400 m (Bayari et al. 2003). studied in detail. The northern slopes of the Pontic Mountains drain Mount Ararat (Agri˘ Dagi),˘ a dormant stratovolcano into the Black Sea and receive some of the highest pre- situated in the easternmost Taurus Mountains, is the cipitation levels in Turkey. In the east of this area, for highest peak in Turkey (5,137 m) and is covered by example, mean annual precipitation exceeds 2,000 mm an ice cap of about 10 km2. This represents the largest (Kurter 1991). As a result, the snowline on the north- single ice mass on any Mediterranean mountain. The ern slopes is between 3,100 and 3,400 m and this is ice cap extends down to c.4,100 m and has a snow- considerably lower than on most other mountains in line altitude of c.4,300 m (Kurter and Sungur 1980). Turkey. At least twelve small glaciers exist in the Pontic Glaciers are found on other Turkish volcanoes, including Mountains and, together, they cover an area of about Mount Süphan (4,058 m) and Mount Erciyes (3,917 m). 2.54 km2 (Çiner 2004). On Mount Süphan, several glaciers occur in the crater, the largest being on a north-facing slope with a length of 1.5 km (Kurter 1991; Çiner 2004). The glacier on The Balkans Mount Erciyes has been the focus of studies throughout Modern glaciers are not present in Greece since the the twentieth century and is known to have retreated permanent snowline is situated well above most of the from a length of 700 m in 1905 to a length of only 380 m highest peaks. The snowline is above 3,000 m in the Pin- by 1983 (Sarikaya 2003; Çiner 2004). These three vol- dus Mountains of northern Greece and above 3,500 m canoes are now dormant, but K-Ar isotope age dating across Crete (Messerli 1980).