Massrörelser i förändring: Ett dynamiskt perspektiv till riskanalyser av slamströmmar i Abiskoområdet
Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
Areas that seemingly have stable slopes may evolve to be areas with unstable slopes. Rapidchanges in stability can cause mass movements, which in turn can cause death and damage tobuildings and infrastructure. The alpine area Abisko-Björkliden in Northern Sweden, have thetopography and the rainfall needed to trigger debris flows and other mass movements. In thearea, there has, in recent years, been an expansion in terms of both buildings and transportation.The combination of natural geomorphological hazards and risks and social needs means thatrisk assessments are central. Risk analysis however relies on static conditions, which means thatthey are only reliable to planning if the climate and other physical parameters are unchanged.An increase in global average temperatures and changing rainfall can alter the physicalparameters and result in secondary effects such as slope instability and resulting debris flows.Climate scenarios indicate that it is likely that sub-Arctic latitudes are experiencing the biggestchange. This study aims to provide a dynamic perspective to an analysis aiming for anidentification of areas in Abisko where debris flows may occur, and thus identify future objectsat risk.In GIS a cost raster was produced by combining and weighing different physical parameters,based on their importance to debris flow initiation. A high-resolution (2 m) digital elevationmodel (DEM) was central to the identification of areas where the potential for debris flowstoday is high. By then modifying parameters such as rainfall, vegetation and permafrost, whichare considered important for slope stability, a map of future areas with potential for debris flowswere given.The results indicate an increase in areas of high potential for debris flows. The new areashowever, lie adjacent to the current high potential areas. Although the distribution increases, itmay be the frequency that becomes higher until new equilibrium conditions are reached. Anincreased potential for debris flows could be followed by an increase in risk, unless adjustmentsof society are made to cope with the new conditions. The identification of future debris flowprone areas can contribute to such adaptation.
Place, publisher, year, edition, pages
Other Earth and Related Environmental Sciences
IdentifiersURN: urn:nbn:se:su:diva-106530OAI: oai:DiVA.org:su-106530DiVA: diva2:736987