Declining discharge of glacier outburst floods through the Holocene in central Patagonia
| Autor: | Varyl R. Thorndycraft, Alejandro Dussaillant, Carlos Sancho, María José Machado, Gerardo Benito, Alicia Medialdea |
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| Přispěvatelé: | Ministerio de Ciencia, Innovación y Universidades (España), University of London |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
010506 paleontology
Archeology Global and Planetary Change geography geography.geographical_feature_category 010504 meteorology & atmospheric sciences Flood myth Magnitude (mathematics) Geology Glacier Geomorphology Outburst flood South America 01 natural sciences GLOFs Interglacial Palaeohydrology Physical geography Glacial period Ecology Evolution Behavior and Systematics Holocene 0105 earth and related environmental sciences Palaeosols |
| Zdroj: | Digital.CSIC. Repositorio Institucional del CSIC instname Digital.CSIC: Repositorio Institucional del CSIC Consejo Superior de Investigaciones Científicas (CSIC) |
| Popis: | Glacier outburstfloods are a major hazard in glacierized catchments. Global analyses have shownreduced frequency of glacierfloods over recent decades but there is limited longer-term data on eventmagnitude and frequency. Here, we present a Holocene palaeoflood record from the Río Baker (ChileanPatagonia), quantifying the discharge and timing of glacierfloods over millennial timescales. A cata-strophicflood of 110,000 m3/s (0.11 Sv) occurred at 9.6±0.8 ka, duringfinal stages of the Late GlacialInterglacial Transition, followed byfiveflood-phases coeval or post-dating Holocene neoglacials. Highestflood frequencies occurred at 4.3e4.4 ka, with 26floods of minimum discharges of 10,000e11,000 m3/s,and 0.6 ka with 10floods exceeding 4600e5700 m3/s. The largest modern outburstflood recordedsurpassed ~3810 m3/s. Thus glacierflood magnitude declines from the order of 0.1 to 0.01 Sv over theEarly to Mid Holocene, and to 0.001 Sv in the instrumental record. GB was supported by the Spanish Ministry of Science, Innovation and Universities. VT would like to thank the Natural Resources Defence Council and Royal Holloway University of London Research Strategy Fund (RHUL-RSF) for funding initialfield visits that led tothis research. AD thanks equipment and field support from CIEP, B.Reid, DGA-Aysen, J. Tureo, C. Meier, C. Olivares, H. Soto, M. Williams(U Greenwich) and NERC-GEF. Xavier Rodriguez-Lloveras providedfield assistance duringfield work in April 2014. |
| Databáze: | OpenAIRE |
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