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  • The extremeness of extreme events
  • Extreme events and the transformation of landscape
  • Concept ; Drainage network ; Exceptional event ; Human impact ; Man-environment relations ; Natural hazards ; Plant cover ; Precipitation ; Rill wash ; Soil erosion ; Watershed
  • of a) the interaction between extreme events and human activity; b) developments in hillslope hydrology, and c) emergences of our understanding of non-linear behaviour.
  • Extreme event in the last 200 years in the Upper Vistula Basin : their palaeohydrological implications
  • Exceptional event ; Hydrology ; Palaeogeography ; Palaeohydrology ; Poland ; Precipitation ; Upper valley ; Wisła
  • To provide characteristics of present-day extreme events which may serve as a key to better recognition of past hydrological changes, the upper Vistula basin was taken as an example. The observations are mainly related to last 100-150 years
  • of events. Only first half of 19-th century, the last phase of the Little Ice Age shows higher frequency of extreme events. This study shows also a great regional diversity in effects of extreme events. Therefore all recontruction of the humid phases during
  • . The A. distinguish the effects of heavy downpours, continuous rains and extreme rainy seasons, as well as snowmelt floods visible in transformation of slopes and river channels. This examination shows a random distribution in 20-th century with few clusterings
  • Postglacial extreme events and human action in the transformation of Estonian topography and landscapes
  • Extreme events and the transformation of landscape
  • In Estonia, extreme events have been caused by meteorite explosions, earthquakes, and neotectonic processes, heavy storms, karst phenomena and human impact. Investigation of past processes provides a major key in predicting the changes that could
  • Extreme events in the context of late Quaternary environmental change
  • Extreme events and the transformation of landscape
  • Climatic variation ; Exceptional event ; Fluvial processes ; Geomorphology ; Human impact ; Impact ; Landscape ; Landslide ; Plant canopy ; Quaternary ; Slope gradient
  • The significance of extreme events in landform change is discussed in the context of the late Quaternary. Millennia-scale cycles of climate change are less than the relaxation times of most landform systems and have led to widespread disequilibrium
  • time and research needs to establish the role of individual events within this timescale of enquiry.
  • Extreme precipitation events on the northern side of the Tatra Mountains
  • Extreme events and the transformation of landscape
  • This article reviews the occurrence and variability of extreme precipitation on the northern slope of the Tatra Mountains (southern Poland), using rainfall amounts of duration from 1 to 30 days. Daily data from 76 years (1927-2002) are used
  • Spatial and temporal characteristics of extreme-high-summer-temperature events in the south-central United States
  • Anomalie climatique ; Changement global ; Etats-Unis ; Etats-Unis du Sud ; Eté ; Humidité atmosphérique ; Précipitation ; Température ; Température extrême ; Variabilité climatique ; Variation spatiale
  • . Precipitation and rain days were significantly correlated with extreme temperature events. Hence, the precipitation climatology may be important to understand in the assessment of the future of extreme 38°C events.
  • This research identifies spatial and temporal patterns of extreme high summer temperatures in the south-central United States, a region that is susceptible to excessive heat: Arkansas, Louisiana, Mississippi, Oklahoma, Tennessee, and Texas
  • significant impact on organism range and success. The extreme-event approach suggests that a few unique events have the greatest impact. A review of the literature seems to indicate a movement of bioclimatologists toward the extreme-event approach.
  • Geomorphic effects of the extreme rainfall event of 20-21 July, 2004 in the Latnjavagge catchment, northern Swedish Lapland
  • Erosion ; Exceptional event ; Lapland ; Mass movement ; Mudflow ; Precipitation ; Sediment budget ; Suspended load ; Sweden ; Watershed
  • Mass transfers triggered by a rare rainfall event on 20-21 July, 2004, in the Latnjavagge catchment in the higher Abisko mountain region, are quantified and analysed in direct comparison with mean annual mass transfers in this drainage basin
  • . A reliable estimation of the recurrence intervals of such rare events is especially problematic. The general problem of defining an adequate length of process monitoring programmes is pointed out.
  • The role of extreme meteorological events in the shaping of mountain relief
  • On appelle généralement événement extrême un événement dont la fréquence est inférieure à 1fois par an. L'A. essaie d'évaluer l'impact d'un certain nombre d'événements météorologiques de ce type sur le relief et en particulier sur les versants. (Cch).
  • Intra-storm attributes of extreme storm events in the Drakensberg, South Africa
  • Atmospheric circulation ; Exceptional event ; KwaZulu-Natal ; Mountain ; Precipitation ; Rainstorm ; South Africa ; Spatial distribution ; Water erosion
  • Intra-storm rainfall attributes were analyzed for 49 extreme storm events at 5 locations in the KwaZulu-Natal Drakensberg. Three stations located in the mountain foothills and two stations sited on the escarpment edge above 2800 m a.s.l. provide
  • the first detailed intra-storm data for the Drakensberg. Extreme rainfall events were found to vary in duration and in depth, but all stations measure a clear exponential distribution of cumulative kinetic energy content of storm rainfall over time. Further
  • Extreme climate events over northern China during the last 50 years
  • Agroclimatologie ; Années 1956-2001 ; Chine ; Chine du Nord ; Climat ; Extrême climatique ; Pluie torrentielle ; Précipitation ; Série chronologique ; Température ; Tendance du climat
  • -September, the rainy season. Heavy rain evenys show no significant show no significant secular trend. There is a weak and non-significant upward trend in frequency of extremely high temperatures from the 1950s to the mid-1990s. But the number of hot events
  • Climate extremes for agricultural-pasture transitional zone, northern China are analyzed on the basis of daily mean temperature and precipitation observations for 31 stations in the period 1956-2001. Analysis season for precipitation is May
  • increases as much as twice since 1997. The frequency of low temperature events have been decreasing steadily since the 1950s.
  • Attributing weather extremes to climate change : A review
  • Action anthropique ; Adaptation ; Attribution ; Changement climatique ; Concept ; Dégât ; Extrême climatique ; Relation société-environnement
  • Adaptation ; Attribution ; Climate extreme ; Climatic change ; Concept ; Damage ; Human impact ; Society-environment relationship
  • In this progress report, the A. analyses the nascent science of extreme weather event attribution by examining the field in 4 stages : motivations for extreme weather attribution, methods of attribution, some example case studies and the politics
  • of weather event attribution. There remain outstanding political dangers and obstacles for extreme weather attribution if it is to be used, as some claim it can and should be, for guiding climate adaptation investments, for servicing the putative loss
  • and damage agenda of the UN Framework Convention on Climate Change or for underpinning legal claims for liability for damages caused by extreme weather.
  • The dynamics to selected extreme climatic events in Poland
  • Atmospheric circulation ; Climate ; Climatic variability ; Exceptional event ; Poland ; Precipitation ; Time series ; Twentieth Century ; Wind
  • This article presents the variability to selected extreme climatic phenomena in Poland in the second half of the 20th century. The main attention is paid to the search for exceptional values for indicators or trends that might be regarded as effects
  • Dam breach reconstruction of the Blažňov pond caused by extreme hydrologifcal event
  • Czech Republic ; Dam ; Exceptional event ; Flood ; Hydrodynamics ; Hydrology ; Model
  • of the flood extremity and flood extent the hydrodynamic model HEC-RAS was applied. - (EN)
  • Frequency of rare weather events during periods of extreme climate
  • This paper only deals with two types of extremes, namely low minimum temperatures during the growing season and, to some extent, extreme areal precipitation during 24 hours. The only parameter used to characterize the climate is the average
  • Modelling the geomorphological impact of climatic variability and extreme events in a semi-arid environment
  • properties and process is apparent in the results. The A. concludes with the observation that the majority of significant soil erosion events in Castilla La Mancha (CLM) occur as a result of extreme precipitation events rather than slow progressive land
  • degradation. In this way, badlands are the relic of past climatic extremes and not necessarilyan indicator of present-day desertification.
  • Holocene climate fluctuations and geomorphic impact of extreme events in Svalbard
  • intervals for debris flows and slush avalanches, and the life-expectancy of resulting landforms are estimated. Correlating extreme events and climate fluctuations in the Scandinavian mountains is difficult because of the low frequency of major slush stream
  • Geomorphological investigations, detailed mapping and lichenometrical surveys carried out at 27 sites located in northwest and central Spitsbergen provide new insight into the history of major slush stream and debris flow events. Recurrence
  • events and of the brief lifetime of debris flow features.
  • A regional analysis of the effects of largest events on soil erosion
  • Cultivated land ; Eastern United States ; Extreme event ; Precipitation ; Regional analysis ; Soil erosion ; Spatial analysis ; Time series ; United States of America
  • Analyse régionale ; Analyse spatiale ; Erosion des sols ; Etats-Unis ; Etats-Unis de l'Est ; Phénomène extrême ; Précipitation ; Sol cultivé ; Série chronologique
  • Alternatively, the AA. define extreme events as the largest events sorted by rank, whatever their absolute magnitude. The new approach applied to soil erosion is that, whatever the magnitude of soil eroded, erosion is a time compressed process
  • and the percentage contribution to total soil erosion by the few largest events (regardless of their magnitude) is negatively related to the total number of daily soil erosion events recorded. The AA. present here a geographical analysis of the effects of largest
  • daily event on soil erosion by comparing 594 erosion plots located in agricultural fields under various climatic temperate conditions across the central-east of the USA. It is shown that the n-largest events contribution not differ between regions of USA
  • . Time compression pattern is expressed by an empirical power law. Erosion research validation require a minimum number of daily events.
  • The relationship of extreme precipitation events to weather conditions in Nordland, Norway
  • The AA. examined the distribution of extreme daily precipitations events in relation to weather conditions, in the county of Nordland. Precipitation data included 88 weather stations and cover the period January 1964 - March 2002. Over this period
  • , extreme precipitations took 2 forms : frontal precipitation (associated with a warm or cold front) and warm sector precipitation (associated with the air masses between 2 fronts). The analyses show that 57% of the extreme daily precipitation situations
  • Differing responses to extreme rainfall events in headwater areas recorded by wood anatomy in roots (Gorce Mountains, Poland)
  • Carpathian Mountains ; Dendrogeomorphology ; Dendrology ; Extreme event ; Mass movement ; Poland ; Precipitation ; Root system ; Watershed
  • Années 1944-2001 ; Bassin-versant ; Carpates ; Dendrogéomorphologie ; Dendrologie ; Mouvement de masse ; Phénomène extrême ; Pologne ; Précipitation ; Système racinaire
  • Fieldwork was carried out in the Gorce Mountains, a range of flysch-type mountains in the Polish Carpathians. In order to date extreme geomorphic events precisely, a dendrogeomorphic approach was performed based on anatomical changes in exposed
  • continuous rainfalls in 1997 and 2001. This research provides a fundamental review of dendrogeomorphological methodology applied to the identification of extreme geomorphic events acting within headwater areas.
  • of the headwater area. In the upper part of the headwater area, anatomical changes within the roots were observed when heavy rainfall events occurred, i.e. in 1958, 1970, 1971, 1972, and 1985. Roots in the lower part of the headwater area had become exposed during