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This commentary uses Google Books N-grams to briefly explore the changing use of the word geomorphology in books published in British English and American English. Both show a decline in the use of the term geomorphology in recent years. A singular feature of the British data is a very sharp rise and fall in the use of term geomorphology in books published since 1980. The steep falling limb (post 1993) of this curve is of particular concern and several possible explanations are put forward including, since 1986, the influence exerted by Research Assessment Exercises on publication practice in UK universities. The N-gram trends pose important questions for all geomorphologists and we should monitor them to gain a better understanding of where we need to be most visible to ensure the long-term health of our discipline. Copyright © 2014 John Wiley & Sons, Ltd.

A major reduction in summer temperatures during a Middle Pleistocene glacial cycle caused the most extensive glaciation recorded in the Mediterranean region. Glaciers in the mountains of Greece formed during marine isotope stage (MIS) 12 (474 000-427 000 years BP) under climatic conditions characterised by mean summer temperatures at least 11 °C cooler than today and annual precipitation of ≤ 2300 mm at the equilibrium line altitude (1741 m a.s.l.). This represents the coldest mean summer temperatures recorded in Greece during at least the last 430 000 years. Later Pleistocene glaciations (MIS 6 and 5d-2) were characterised by warmer summer temperatures and higher annual precipitation. © 2006 Elsevier B.V. All rights reserved.

Glacial and periglacial landforms are widespread in the mountains of the Mediterranean region. The evidence for glacial and periglacial activity has been studied for over 120 years and it is possible to identify three phases of development in this area of research. First, a pioneer phase characterized by initial descriptive observations of glacial landforms; second, a mapping phase whereby the detailed distribution of glacial landforms and sediments have been depicted on geomorphological maps; and, third, an advanced phase characterized by detailed understanding of the geochronology of glacial sequences using radiometric dating alongside detailed sedimentological and stratigraphical analyses. It is only relatively recently that studies of glaciated mountain terrains in the Mediterranean region have reached an advanced phase and it is now clear from radiometric dating programmes that the Mediterranean mountains have been glaciated during multiple glacial cycles. The most extensive phases of glaciation appear to have occurred during the Middle Pleistocene. This represents a major shift from earlier work whereby many glacial sequences were assumed to have formed during the last cold stage. Glacial and periglacial deposits from multiple Quaternary cold stages constitute a valuable palaeoclimatic record. This is especially so in the Mediterranean mountains, since mountain glaciers in this latitudinal zone would have been particularly sensitive to changes in the global climate system. © 2006 Edward Arnold (Publishers) Ltd.

Relict rock glaciers have been identified and mapped in the high cirques of Mount Tymphi, in the Pindus mountains of northwest Greece. They are periglacial forms and represent the most recent cold-stage landforms in an area that displays widespread evidence of Pleistocene glaciation. It is likely that these features formed during the Last Glacial Maximum (Late Wurmian) as talus rock glaciers, and beneath small cirque glaciers as debris rock glaciers. Comparisons with modern rock glacier–climate relationships suggests mean annual temperatures of ca. 8–9°C lower than present at their time of formation. This temperature reconstruction is in good agreement with recent palaeoclimatic reconstructions for the northern Mediterranean based on a general circulation model. Moreover, as rock glaciers are typical of cold and relatively dry mountain regions, their presence is consistent with palaeobotanical and lake-level data suggesting a cold and relatively dry climate for the Last Glacial Maximum in Greece. However, the presence of small cirque glaciers above some rock glaciers suggests that although precipitation must have been low enough to preclude glacier extension down to lower altitudes, it was not so low as to inhibit glacier formation entirely. Copyright © 2003 John Wiley & Sons, Ltd.

Strontium isotopic and petrologic information, obtained from sediment cores collected in the Nile delta of Egypt, indicate that paleoclimatic and Nile baseflow conditions changed considerably from about 4200 to 4000 cal yr B.P. in the Nile basin. Our study records a higher proportion of White Nile sediment transported during the annual floods at ca. 6100 cal yr B.P. than towards 4200 cal yr B.P., at which time suspended sediment from the Blue Nile formed a significantly larger fraction of the total load. This resulted from a decrease in vegetative cover and an increase in erosion rate accompanying the marked decline in rainfall. These new geoscience data indicate major changes in annual flooding and baseflow of the river Nile, marked short-term paleoclimatic-related events that may in part have led to the collapse of the Old Kingdom. © 2003 Wiley Periodicals, Inc.

It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rocksheiter and cave sediment records of the area. In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record. © 2001 John Wiley & Sons, Inc.

Evidence for large floods in the Pindus Mountains of Northwest Greece during the Lateglacial period is provided by a sequence of fine-grained slackwater sediments preserved beneath the Late Upper Paleolithic deposits at Boila rockshelter in the Voidomatis River basin. We have applied a quantitative sediment fingerprinting approach to estimate the relative contributions from different catchment sediment sources to these flood sediments. Our approach utilizes recent developments in hydrology and fluvial geomorphology where researchers have used sediment properties to establish the source of suspended sediments transported in rivers during present-day flood events. The data set used to create the composite sediment source fingerprint comprised nine tracer properties including eight trace elements (determined by X-ray fluorescence techniques) and magnetic susceptibility. The Boila sequence has been dated by conventional and AMS radiocarbon techniques, and the central and upper part of the flood sediments were deposited between ca. 14,310 ± 200 and 13,960 ± 260 radiocarbon yr B.P. These flood events took place during the global cooling associated with Heinrich event 1, although the sediment fingerprinting data indicate that glacial activity in the Voidomatis basin was no longer supplying large volumes of sediment to the fluvial system at this time. The slackwater deposits are mainly derived from flysch sediments and soils from nonglaciated parts of the Voidomatis River basin. The results of this approach compare well with lithological estimates based on micromorphological analyses and are in good agreement with existing data on the Late Pleistocene and Holocene behavior of this river system. The slackwater sediments offer important insights into the nature of the river environment and the wider catchment system during the Lateglacial period when the Klithi rockshelter (ca. 2 km upstream of Boila) was the focus of Paleolithic activity in the Voidomatis Gorge. In appropriate depositional contexts, quantitative sediment fingerprinting constitutes a valuable geoarchaeological tool for the investigation of rockshelter and cave sediment records that can improve our understanding of site formation processes and their broader environmental context. This approach is a valuable complement to the micromorphological investigation of rockshelter sediment records. © 2001 John Wiley & Sons, Inc.

diffraction (XRD) of the fine matrix component of four alluvial units and modern channel sediments in the Voidomatis River Basin of northwest Greece shows that fine sediment sources have changed considerably during the late Quaternary. The matrix fraction of the modern channel sediments is derived predominantly from erosion of local flysch rocks and soils. During the last glaciation, however, the fine sediment load of the Voidomatis River was dominated by glacially-ground, finely comminuted limestone materials. Limestone-derived fine sediment is not produced in significant amounts under modern climatic conditions. By combining this XRD work with a detailed programme of clast lithologic 1 analysis we have reconstructed former bedload and fine sediment load composition. The lithological properties of both the coarse (8-256 mm) and fine (< 63 μm) elements of the sediment load have varied markedly during the late Quaternary. A simple, semiquantitative assessment of fine sediment mineralogy, using diffractogram peak-height data, has provided a valuable complement to the information gathered from more traditional clast lithological techniques. Together, in favourable geological settings, fine fraction mineralogy and clast lithological analysis can provide a valuable tool for the reconstruction of late Quaternary alluvial environments.

Recent research in the mountains of the Mediterranean has attempted to establish the timing of the maximum extent of glaciers during the last cold stage. Several dating methods have been utilised and new dating frameworks have emerged in key areas. In several places, multiple dating techniques (radiocarbon, optically stimulated luminescence, U-series) applied to glacial and associ- ated sediments suggest that local glacier maxima preceded the global Last Glacial Maximum (LGM, ca. 18 14 C ka BP/ 21 cal. ka BP) by at least several thousand years. Studies in Spain, the Pyrenees, the Maritime Alps and Turkey utilising cosmogenic isotope analyses ( 10 Be and 36 Cl), have yielded glacial geochronologies with maxima that correlate closely with the marine isotope record of ice volume and the global LGM. In some cases, the use of different geochronological techniques has led to conflicting evidence for the timing of the local last glacier maxima in the same area. From a palaeoclimate perspective, glacier-climate reconstructions for the local last glacier maxima in the mountains of central Italy, northern Greece and western Turkey indicate that climate was wet and cold. In Italy and Greece the local glacier maxima preceded the driest part of the last cold stage - as indicated by palaeoecological records - by several thousand years. For western Turkey, however, recent cosmo- genic exposure ages combined with glacier modelling suggest a local last glacier maximum charac- terised by cold and wet conditions coinciding with the global LGM. The available evidence indicates that a dichotomy is emerging, not only in our understanding of the timing of glaciation across the Mediterranean, but also in the palaeoclimatic interpretations derived from glacial and palaeoecolo- gical records. Copyright # 2008 John Wiley & Sons, Ltd.

Detailed sedimentological analyses of diamicton sequences in two areas of the Pindus Mountains, Greece, indicate multiple episodes of glacier advance and retreat during cold stages of the Middle-Pleistocene. These glacial sequences represent some of the most southerly in Europe and are important archives of regional and global climate change. The Pindus glaciers were relatively small by world standards and would have been highly responsive to changes in air temperature and precipitation. On Mount Tymphi, at least three phases of glacier advance are recorded within deposits assigned to the Skamnellian Stage (MIS 12). Further north on Mount Smolikas, a thick multiple diamicton sequence records evidence for multiple glacier advances during both the Skamnellian Stage and the Vlasian Stage (MIS 6). These records highlight the dynamic nature of glacier behaviour in the Mediterranean mountains during the Middle Pleistocene and provide new evidence for unstable cold stage climates.

Glacial deposits in locally-glaciated mountain regions are often expressed through their surface form and the study of these deposits constitutes a major branch of geomorphology. Studies of glacial depositional records in mountain areas have often neglected formal stratigraphical procedure resulting in an ad hoc development of quasi-stratigraphical nomenclature. Here, a formal stratigraphical procedure is recommended, since this enables a systematic approach to the subdivision of glacial deposits in mountain regions. Moreover, such an approach facilitates, in some instances, the development of a formal chronostratigraphy that can be compared to regional and global geological time scales. This is important in locally-glaciated mountain regions where glacial deposits represent one of the most important records of cold stage environments. Given that glacial landforms represent a key component of the Quaternary record, maintaining a formal link between geomorphological and geological stratigraphical procedure is a fundamental requirement of a consistent and comparable stratigraphical framework.