Please note that this session was withdrawn and is no longer available in the respective programme. This withdrawal might have been the result of a merge with another session.
GM4.1 | El Niño drivers of surface processes and hazards in mountain regions
El Niño drivers of surface processes and hazards in mountain regions
Convener: Rebekah HarriesECSECS | Co-conveners: Albert Cabre, Elizabeth OrrECSECS, Michelle FameECSECS, Germán Aguilar
Extreme weather events are impacting catchments across North and South America, Africa and East Asia while we prepare for the next EGU meeting in 2024. These events have been linked to a strong warm phase of the El Niño Southern Oscillation (ENSO) and to date, have initiated cascades of impacts along river systems in many southern hemisphere countries. Enhanced periods of geomorphic change, characterised by hazardous processes (flash floods, debris flows, landslides etc.) have been previously identified in Holocene sedimentary archives as linked to the persistence of this climatic phenomenon. An improved understanding of how such periods of more frequent extreme hydrological events impact and propagate through river systems is needed to constrain their evolving hazard potential. These cascading impacts may include changes in snowmelt and run off, groundwater flows, vegetation cover and land use, which together alter glacial and periglacial processes, permafrost dynamics, hillslope activity, sediment export, river channel evolution and drive hazardous events, including floods, debris flows and landslides.

In this session, we welcome abstracts investigating the impact of ENSO on the geomorphic evolution of river systems and consider the risk posed to riverine communities and infrastructure. This assessment requires cross-disciplinary approaches to disentangle the impact of such extreme events on landscape evolution and explore unprecedented hazard scenarios. These approaches might draw, for example, on catchment hydrology, remote sensing and monitoring, geochronology, and landscape evolution modeling and explore a range of mountain environments.