Nepal is a mountainous, less developed kingdom that straddles the boundary between the Indian and Himalayan tectonic plates. In Nepal, landslides represent a major constraint on development, causing high levels of economic loss and substantial numbers of fatalities each year. There is a general consensus that the impacts of landslides in countries such as Nepal are increasing with time, but until now there has been little or no quantitative data to support this view, or to explain the causes of the increases. In this paper, a database of landslide fatalities in Nepal has been compiled and analysed for the period 1978-2005. The database suggests that there is a high level of variability in the occurrence of landslides from year to year, but that the overall trend is upward. Analyses of the trends in the data suggest that there is a cyclicity in the occurrence of landslide fatalities that strongly mirrors the cyclicity observed in the SW (summer) monsoon in South Asia. Perhaps surprisingly the relationship is inverse, but this is explained through an inverse relationship between monsoon strength and the amount of precipitation in the Hill District areas of Nepal. It is also clear that in recent years the number of fatalities has increased dramatically over and above the effects of the monsoon cycle. Three explanations are explored for this: land-use change, the effects of the ongoing civil war in Nepal, and road building. It is concluded that a major component of the generally upward trend in landslide impact probably results from the rural roadbuilding programme, and its attendant changes to physical and natural systems.
meltwater channels, tunnel valleys, trimlines, limit of key glacigenic deposits, glaciolacustrine deposits, ice-dammed lakes, erratic dispersal patterns, shelf-edge fans, and the Loch LomondReadvance limit of the main ice cap. The GIS contains over 20000 features split into thematic layers (as above). Individual features are attributed such that they can be traced back to their published sources. Given that the published sources of information that underpin this work were derived by a piecemeal effort over 150 years then our main caveat is of data consistency and reliability. It is hoped that this compilation will stimulate greater scrutiny of published data, assist in palaeo-glaciological reconstructions, and facilitate use of field-evidence in numerical ice sheet modelling. It may also help direct field workers in their future investigations.
This paper reviews the evidence presently available (as at December 2003) in an effort to stimulate further research on the last British Ice Sheet and promote a reconstruction of ice sheet behaviour based on glacial geology and geomorphology. The wide range of evidence that has been scrutinized for inclusion on the glacial map is assessed with respect to the variability of its quality and quantity and the existing controversies in ice sheet reconstructions. Landforms interpreted as being of unequivocal ice-marginal origin (moraines, ice-contact glacifluvial landforms and lateral meltwater channels) and till sheet margins are used in conjunction with available chronological control to locate former glacier and ice-sheet margins throughout the last glacial cycle. Subglacial landforms (drumlins, flutings and eskers) have been used to demarcate former flow patterns within the ice sheet. The compilation of evidence in a regional map is crucial to any future reconstructions of palaeo-ice sheet dynamics and will provide a clearer understanding of ice sheet configuration, ice divide migration and ice thickness and coverage for the British Ice Sheet as it evolved through the last glacial cycle.2
meltwater channels, tunnel valleys, trimlines, limit of key glacigenic deposits, glaciolacustrine deposits, ice-dammed lakes, erratic dispersal patterns, shelf-edge fans, and the Loch LomondReadvance limit of the main ice cap. The GIS contains over 20000 features split into thematic layers (as above). Individual features are attributed such that they can be traced back to their published sources. Given that the published sources of information that underpin this work were derived by a piecemeal effort over 150 years then our main caveat is of data consistency and reliability. It is hoped that this compilation will stimulate greater scrutiny of published data, assist in palaeo-glaciological reconstructions, and facilitate use of field-evidence in numerical ice sheet modelling. It may also help direct field workers in their future investigations.
16The central sector of the last British-Irish Ice Sheet (BIIS) was characterised by considerable 17 complexity, both in terms of its glacial stratigraphy and geomorphological signature. This 18 complexity is reflected by the large number and long history of papers that have attempted to 19 decipher the glaciodynamic history of the region. Despite significant advances in our 20 understanding, reconstructions remain hotly debated and relatively local, thereby hindering 21 attempts to piece together BIIS dynamics. This paper seeks to address these issues by 22reviewing geomorphological mapping evidence of palimpsest flow signatures and providing 23 an up-to-date stratigraphy of the region. Reconciling geomorphological and sedimentological 24 evidence with relative and absolute dating constraints has allowed us to develop a new six-25 stage glacial model of ice-flow history and behaviour in the central sector of the last BIIS, 26 with three major phases of glacial advance. This includes: I. Eastwards ice flow through 27 prominent topographic corridors of the north Pennines; II. Cessation of the Stainmore ice 28 flow pathway and northwards migration of the North Irish Sea Basin ice divide; III. 29 Stagnation and retreat of the Tyne Gap Ice Stream; IV. Blackhall Wood-Gosforth Oscillation; 30 V. Deglaciation of the Solway Lowlands; and VI. Scottish Re-advance and subsequent final 31 retreat of ice out of the central sector of the last BIIS. The ice sheet was characterised by 32 considerable dynamism, with flow switches, initiation (and termination) of ice streams, draw-33 down of ice into marine ice streams, repeated ice-marginal fluctuations and the production of 34 large volumes of meltwater, locally impounded to form ice-dammed glacial lakes. 35Significantly, we tie this reconstruction to work carried out and models developed for the 36 entire ice sheet. This therefore situates research in the central sector within contemporary 37 understanding of how the last BIIS evolved over time. 38
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