Rio Colonia, a tributary of the Baker River, drains the Northern Patagonia Icefield, and is experiencing a new cycle of Glacial-Lake Outburst Floods (GLOFs). The sudden draining of c. 200 hm3 from glacier-dammed Cachet 2 Lake, results in a 3-5 fold increase in discharge in Baker River, Chile's largest. Suspended sediment concentration also increases 8-fold and load 10 to 20-fold, totalling almost 5% of the annual load.Yet baseline studies of one of the dams of a US$7 billion hydropower project to flood the confluence doesn't consider GLOF dynamics. Moreover, Patagonia, the world largest complex of icefields and temperate glaciers, is experiencing warming trends and higher glacial-river flows. And the region is one of the largest unknowns in the global sediment flux to oceans. Here we compare present morphology and dynamics with the 1967-2007 outburst-free period and the previous outburst cycle that ended in 1968, with particular focus on the Colonia/Baker river confluence. Floodplain vegetation cover shows significant changes. Implications for a recently approved Baker dam are discussed.
Scheda prodotto non validato
I dati visualizzati non sono stati ancora sottoposti a validazione formale da parte dello Staff di IRIS, ma sono stati ugualmente trasmessi al Sito Docente Cineca (Loginmiur).
Titolo: | Glacial-lake outburst flood effects on Colonia River morphology, Chilean Patagonia |
Autori: | E., Bastianon; Bertoldi, Walter; A., Dussaillant |
Autori Unitn: | |
Titolo del volume contenente il saggio: | River Flow 2012 - Proceedings of the International Conference on Fluvial Hydraulics |
Luogo di edizione: | London |
Casa editrice: | Taylor & Francis Group |
Anno di pubblicazione: | 2012 |
Codice identificativo Scopus: | 2-s2.0-84867948915 |
Codice identificativo ISI: | WOS:000347871500076 |
ISBN: | 9780415621298 |
Handle: | http://hdl.handle.net/11572/94611 |
Appare nelle tipologie: | 04.1 Saggio in atti di convegno (Paper in proceedings) |