Journal Article

Repeated glacial-lake outburst floods in Patagonia: an increasing hazard

Dussaillant, Alejandro, Espinoza, Fabián, Meier, Claudio, Benito, Gerardo, Buytaert, Wouter, Carling, Paul

2010

نظرة عامة

Five similar glacial-lake outburst floods (GLOFs) occurred in April, October, December 2008, March and September 2009 in the Northern Patagonia Icefield. On each occasion, Cachet 2 Lake, dammed by the Colonia Glacier, released circa 200-million m³ water into the Colonia River. Refilling has occurred rapidly, such that further outbreak floods can be expected. Pipeflow calculations of the subglacial tunnel drainage and 1D hydraulic models of the river flood give consistent results, with an estimated peak discharge surpassing 3,000 m³ s⁻¹. These floods were larger in magnitude than any flood on record, according to gauged data since 1963. However, geomorphological analysis of the Colonia valley shows physical evidence of former catastrophic outburst floods from a larger glacial-lake, with flood discharges possibly as high as 16,000 m³ s⁻¹. Due to potential impacts of climate change on glacier dynamics in the area, jökulhlaups may increase future flood risks for infrastructure and population. This is particularly relevant in view of the current development of hydropower projects in Chilean Patagonia.

• الناشر: Dordrecht : Springer Netherlands,Springer Netherlands,Springer,Springer Nature B.V
• موضوع: Civil Engineering / Climate change / Earth and Environmental Science / Earth Sciences / Earth, ocean, space / Engineering and environment geology. Geothermics / Environmental Management / Exact sciences and technology / Floods / Freshwater / Geomorphology / Geophysics/Geodesy / Geotechnical Engineering & Applied Earth Sciences / Glacial-lake / Glaciers / Hazards / Hydrogeology / Hydrology / Jökulhlaup / Lakes / Natural Hazards / Natural hazards: prediction, damages, etc / Original Paper / Outburst flood / Outbursts / Risk / Rivers / Valleys