Active subglacial lakes and channelized water flow beneath the Kamb Ice Stream
| Autor: | Ted Scambos, Byeong-Hoon Kim, Won Sang Lee, Ki-Weon Seo, Choon-Ki Lee |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
lcsh:GE1-350
geography geography.geographical_feature_category 010504 meteorology & atmospheric sciences Water flow Ice stream lcsh:QE1-996.5 Channelized STREAMS 15. Life on land 010502 geochemistry & geophysics 01 natural sciences Ice shelf Subglacial stream lcsh:Geology 13. Climate action Subglacial eruption Subglacial lake Geomorphology Geology lcsh:Environmental sciences 0105 earth and related environmental sciences Earth-Surface Processes Water Science and Technology |
| Zdroj: | The Cryosphere, Vol 10, Iss 6, Pp 2971-2980 (2016) |
| ISSN: | 1994-0424 1994-0416 |
| Popis: | We identify two previously unknown subglacial lakes beneath the stagnated trunk of the Kamb Ice Stream (KIS). Rapid fill-drain hydrologic events over several months are inferred from surface height changes measured by CryoSat-2 altimetry and indicate that the lakes are probably connected by a subglacial drainage network, whose structure is inferred from the regional hydraulic potential and probably links the lakes. The sequential fill-drain behavior of the subglacial lakes and concurrent rapid thinning in a channel-like topographic feature near the grounding line implies that the subglacial water repeatedly flows from the region above the trunk to the KIS grounding line and out beneath the Ross Ice Shelf. Ice shelf elevation near the hypothesized outlet is observed to decrease slowly during the study period. Our finding supports a previously published conceptual model of the KIS shutdown stemming from a transition from distributed flow to well-drained channelized flow of subglacial water. However, a water-piracy hypothesis in which the KIS subglacial water system is being starved by drainage in adjacent ice streams is also supported by the fact that the degree of KIS trunk subglacial lake activity is relatively weaker than those of the upstream lakes. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|