A severe rainstorm of high intensity occurred on 20th-21st November 2000, in the region of Pistoia, Tuscany, Italy, which triggered, within the entire province, over 50 landslides. These landslides can be broadly defined as complex earth slides-earth flows,originating as rotational slides that develop downslope into a flow. In this paper, two such landslides have been investigated by modelling the process of rainwater infiltration, the variations in both the positive and negative pore water pressures and their effect on slope stability during the storm. For both sites, results from morphometric and geotechnical analyses were used as a direct input to the numerical modelling. A modified Chu, 1978 approach was used to estimate the surface infiltration rate by adapting the original Green and Ampt, 1911 equations for unsteady rainfall intensity in conjunction with the surficial water balance. For transient conditions, a finite element analysis was used to model the fluctuations in pore water pressure during the storm, with the computed surface infiltration rate as the surface boundary condition. This was then followed by the application of the limit equilibrium Morgenstern and Price, 1965 slope-stability method, using the temporal pore water pressure distributions derived from the seepage analysis. From this methodology, a trend for the factor of safety was produced for both landslide sites. These results indicate that the most critical time step for failure was a few hours following the rainfall peak.

An analysis of landslide occurrence in the low permeability terrain of Porretta-Vergato, Italy, related to prolonged rainfall patterns is presented. Data sets collected over nearly a century are statistically analysed. The pattern of the landslide hazard is considered and related to precipitation at the basin scale in order to enhance the understanding between the two parameters and assess their temporal changes, as well as interrelationships. Landslide incidence generally follows the periodic pattern of precipitation with a lag of approximately six months, which is believed to relate to the time necessary for the ground water to reach a critical level to initiate slope failure. There also appears to be a two-stage pattern of precipitation which induces most landslides: a preparatory period, where the landslide is destabilized and conditioned for slope failure, followed by a more intense period of rainfall that triggers or provokes the event. These initial findings point to the need for further studies to verify such unstable situations.

Coastal fortifications in South East England have been continuously built and rebuilt over the centuries according to the ebb and flow of politics in Europe. This paper covers an extensive historical period from the influx of the Romans to the present day, detailing how landslides and coastal erosion have affected the numerous constructions along this stretch of coastline. Principal landslide-prone strata form extensive sections of this part of the coast with the tendency to be weak and highly susceptible to marine attack and cliff retreat. Fortifications have been built out of necessity in strategic positions without full consideration of the ground upon which they have been constructed. The continual construction of fortifications along this section of coastline constitutes an unparalleled archaeological record, but it is one that is under continuous threat from coastal erosion and landsliding.

Abstract:The southern coast of the Caspian Sea in northern Iran is bordered by a mountain range with forested catchments which are susceptible to droughts and floods. This paper examines possible changes to runoff patterns from one of these catchments in response to climate change scenarios. The HEC-HMS rainfall-runoff model was used with downscaled future rainfall and temperature data from 13 Global Circulation Models, and meteorological and hydrometric data from the Casilian (or 'Kassilian') Catchment. Annual and seasonal predictions of runoff change for three future emissions scenarios were obtained, which suggest significantly higher spring rainfall with increased risk of flooding and significantly lower summer rainfall leading to a higher probability of droughts. "Flash floods" arising from extreme rainfall may become more frequent, occurring at any time of year. These findings indicate a need for strategic planning of water resource management and mitigation measures for increasing flood hazards. Prediction of climate change effects on the runoff regime of a forested catchment in northern Iran AbstractThe southern coast of the Caspian Sea in northern Iran is bordered by a mountain range with forested catchments which are susceptible to droughts and floods. This paper examines possible changes to runoff patterns from one of these catchments in response to climate change scenarios. The HEC-HMS rainfall-runoff model was used with downscaled future rainfall and temperature data from 13 Global Circulation Models, and meteorological and hydrometric data from the Casilian (or 'Kassilian') Catchment. Annual and seasonal predictions of runoff change for three future emissions scenarios were obtained, which suggest significantly higher spring rainfall with increased risk of flooding and significantly lower summer rainfall leading to a higher probability of droughts. "Flash floods" arising from extreme rainfall may become more frequent, occurring at any time of year. These findings indicate a need for strategic planning of water resource management and mitigation measures for increasing flood hazards.

The coastline of Southeast Britain is formed in sedimentary rocks of Jurassic, Cretaceous and Tertiary age, the majority of these deposits containing thick strata of mudrocks, which have very low angles of dip. Where these strata are appropriately exposed, particularly at the foot of a coastal slope, they give rise to landslides where all or part of the sliding surface follows a single bed of mudrock. Where the dip of the bedding is steep, such landslides are referred to as dip-slope failures. However, landslides where the basal sliding surface is controlled by the location and orientation of a single argillaceous bed in the sequence are better termed bedding-controlled landslides. In addition, where coastal slopes contain several layers of mudrocks, geometrically similar landslides may occur with perched slide surfaces breaking out at a higher level within the slopes. Landslides with strong bedding-controlled basal shear surfaces are the predominant form of instability along the southeast coastline of Britain. Many of the individual landslide cases used in this paper have been studied separately over many years. The general similarity of the different records is discussed, drawing important inferences on a number of aspects of these landslides with a variety of basal sliding surface geometries.Keywords Landslides · Bedding-control · Southeast Britain · Coast IntroductionThe coastal zone of Southeast Britain has been a proving ground for landslide research for decades and, in some respects and locations, for centuries. The combination of sequences of sedimentary rocks within which there are appreciable thicknesses of mudrocks (i.e. stiff fissured clays), relatively low angles of dip, generally wet climate, and active coastal erosion leads to the occurrence of particular landslide types. These are generally bedding-controlled landslides with rotational and translational elements (Bromhead and Harris 1999). They are sometimes formed either wholly or mainly of large, displaced blocks of the parent rock mass, a situation which is commonest where the landslides have occurred comparatively recently. Alternatively, the landslide mass may be primarily formed from debris, and the landslide may represent the sum total of many instances of failure over long periods of time. Mudslides are also very common along the coastline and are usually associated with strongly localised water inputs to the slope. Less commonly, coastal slopes exhibit toppling behaviour, and there are stretches of coastal cliffs (usually in a single lithology) where rockfalls occur. Other common morphologies found along this stretch of coastline are low-lying tracts of land with coastal mudflats and marshes (sometimes reclaimed), shingle spits and beaches, as well as drowned valleys. Figure 1 identifies the major locations mentioned in the text and the region of the southeast coastline considered, between the