JÖkulhlaups: A reassessment of floodwater flow through glaciers
Tóm tắt
In glaciated catchments, glacier‐generated floods (jökulhlaups) put human activity at risk with large, sporadic jökulhlaups accounting for most flood‐related fatalities and damage to infrastructure. In studies of jökulhlaup hydrodynamics the view predominates that floodwater travels within a distinct conduit eroded into the underside of a glacier. However, some jökulhlaups produce subglacial responses wholly inconsistent with the conventional theory of drainage. By focusing on Icelandic jökulhlaups this article reassesses how floodwater flows through glaciers. It is argued that two physically separable classes of jökulhlaup exist and that not all jökulhlaups are an upward extrapolation of processes inherent in events of lesser magnitude and smaller scale. The hydraulic coupling of multiple, nonlinear components to the flood circuit of a glacier can induce extreme responses, including pressure impulses in subglacial drainage. Representing such complexity in mathematical form should be the basis for upcoming research, as future modeling results may help to determine the glaciological processes behind Heinrich events. Moreover, such an approach would lead to more accurate, predictive models of jökulhlaup timing and intensity.
Từ khóa
Tài liệu tham khảo
Austmann J., 1907, Safn til Sögu Íslands og íslenskra Bókmennta, 252
Baker V. R., 2002, Floods and Megaflood Deposits: Recent and Ancient Examples, 3
Björnsson H., 1974, Explanation of jökulhlaups from Grímsvötn, Vatnajökull, Iceland, Jökull, 24, 1, 10.33799/jokull1974.24.001
Björnsson H., 1975, Subglacial water reservoirs, jökulhlaups and volcanic eruptions, Jökull, 25, 1, 10.33799/jokull1975.25.001
Björnsson H., 1976, Marginal and supraglacial lakes in Iceland, Jökull, 26, 40, 10.33799/jokull1976.26.040
Björnsson H., 1977, The cause of jökulhlaups in the Skaftá River, Vatnajökull, Jökull, 27, 71, 10.33799/jokull1977.27.071
Björnsson H., 1988, Hydrology of Ice Caps in Volcanic Regions
Björnsson H., 2004, Mountain Geomorphology, 155
Chow V. T., 1959, Open‐Channel Hydraulics
Desloges J. R., 1989, Estimates of peak discharge from the drainage of ice‐dammed Ape Lake, British Columbia, Canada, J. Glaciol., 35, 349, 10.3189/S0022143000009278
Elvehøy H., 2002, Extremes of the Extremes: Extraordinary Floods, 31
Fisher D., 1973, Symposium on the Hydrology of Glaciers, 111
Gilbert R., 1971, Observations on ice‐dammed Summit Lake, British Columbia, Canada, J. Glaciol., 10, 351, 10.3189/S0022143000022048
Glazyrin G. E., 1976, Vozmozhnost prognoza kharakteristik pavodov, vyzyvaemykh proryvami lednikovykh ozer, Mater. Gliatsiolog. Issled., 26, 78
Larson G., 2000, Holocene eruptions within the Katla volcanic system, south Iceland: Characteristics and environmental impact, Jökull, 49, 1, 10.33799/jokull2000.49.001
Lawson D. E.(1993) Glaciohydrologic and glaciohydraulic effects on runoff and sediment yield in glacierized basins Monogr. 93‐02 Cold Reg. Res. Eng. Lab. Hanover N. H.
Liestøl O., 1977, Setevatnet, a glacier dammed lake in Spitsbergen, Skr. Nor. Polarinst., 1975, 31
Maizels J. K., 1992, Quaternary Proceedings
Mathews W. H., 1973, Symposium on the Hydrology of Glaciers, 99
McAdam W. H., 1951, Heat Transmission
Nolan M., 1999, Seismic detection of transient changes beneath Black Rapids Glacier, Alaska, U.S.A.: I. Techniques and observations, J. Glaciol., 45, 119, 10.3189/S0022143000003105
Paige R. A., 1955, Subglacial stopping or block calving: A type of glacier ablation, J. Glaciol., 2, 727, 10.3189/S0022143000024977
Paterson W. S. B., 1994, The Physics of Glaciers
Pierson T. C., 1989, Hydrology of Disasters, 220
Raymond C. F., 2000, Debris‐Covered Glaciers, 199
Reid J. R., 1963, Observations of rapid water‐level fluctuations in ice sink‐hole lakes, Martin River Glacier, Alaska, J. Glaciol., 4, 650, 10.3189/S0022143000028239
Richardson D., 1968, Glacier outburst floods in the Pacific Northwest, U.S. Geol. Surv. Prof. Pap., 600, D79
Rist S., 1973, Jökulhlaupannáll 1971, 1972, 1973, Jökull, 23, 55
Röthlisberger H., 1987, Glacio‐fluvial Sediment Transfer: An Alpine Perspective, 207
Shaw J., 1996, Geomorphology Sans Frontières, 181
Sigurðsson O., 2000, Jökulhlaup úr Sólheimajökuli 18. júlí 1999, Jökull, 49, 75, 10.33799/jokull2000.49.075o
Smellie J. L., 2002, Volcano‐Ice Interactions on Earth and Mars, 59
Snorrason Á., 2000, Floods, 198
Snorrason Á., 2002, Floods and Megaflood Deposits: Recent and Ancient Examples, 55
Stefánsdóttir M. B., 1999, Geochemistry of the Earth's Surface, 539
Thórarinsson S., 1939, The ice‐dammed lakes of Iceland with particular reference to their value as indicators of glacier oscillations, Geogr. Ann., 21, 216
Thórarinsson S., 1957, The jökulhlaup from the Katla area in 1955 compared with other jökulhlaups in Iceland, Jökull, 7, 21, 10.33799/jokull1957.07.021
Thórarinsson S., 1958, The Öræfajökull eruption of 1362, Acta Nat., 2
Thórarinsson S., 1974, Vötnin Stríð: Saga Skeiðarárhlaupa og Grímsvatnagosa
Thouret J. C., 1995, Steepland Geomorphology, 63
Walder J. S., 1995, Frequent outburst floods from south Tahoma Glacier, Mount Rainier, U.S.A.: Relation to debris flows, meteorological origin and implications for subglacial hydrology, J. Glaciol., 41, 1, 10.3189/S0022143000017718
Walder J. S., 1997, Destructive Water: Water‐Caused Natural Disasters—Their Abatement and Control, 107
Walski T. M., 2003, Advanced Water Distribution Modeling and Management, 573
Warburton J., 1994, Unusual flood events from an Alpine glacier: Observations and deductions on generating mechanism, J. Glaciol., 40, 176, 10.3189/S0022143000003956
Weertman J., 1962, Variations of the Regime of Existing Glaciers, 31
Wilson L., 2002, Volcano‐Ice Interactions on Earth and Mars, 5
Wolf L. W., 1986, Glacier‐generated earthquakes from Prince William Sound, Alaska, Bull. Seismol. Soc. Am., 76, 367, 10.1785/BSSA0760020367
Zóphóníasson S.(2002) Rennsli í Skaftárhlaupum 1995–2002 Rep. SZ2002/01 Natl. Energy Auth. Reykjavík Iceland.