Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica
The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow fro...
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ftportlandstate:oai:pdxscholar.library.pdx.edu:open_access_etds-6436 2023-05-15T13:52:19+02:00 Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica Cross, Julian Michael 2020-01-03T08:00:00Z application/pdf https://pdxscholar.library.pdx.edu/open_access_etds/5364 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=6436&context=open_access_etds English eng PDXScholar https://pdxscholar.library.pdx.edu/open_access_etds/5364 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=6436&context=open_access_etds In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). Dissertations and Theses Meltwater -- Antarctica -- Taylor Valley Hydrologic models Lakes -- Antarctica -- Taylor Valley Geography Hydrology text 2020 ftportlandstate 2022-01-09T20:05:13Z The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E = 0.47; nRMSE = 0.73). After 2008 the meltwater model significantly under-predicted streamflow and only through decreasing albedo by -30% (equivalent to a decrease of -0.18 on average) did the results match observations (E = 0.79; nRMSE = 0.45). This study provides the first estimate of direct (unmeasured) glacier inflow to the lakes, 69%, 73% and 28%, and sublimation loss rates, 0.37 m yr-1, 0.24 m yr-1 and 0.16 m yr-1, for lakes Bonney, Hoare and Fryxell, respectively. Despite similar meltwater volumes entering lakes Bonney and Fryxell, the difference in basin hypsometry results in a much faster lake rise at Bonney from 2002-13. If future climate conditions match current (1996-2013) conditions, all lakes will rise through the end of the century. Text Antarc* Antarctica McMurdo Dry Valleys polar desert Portland State University: PDXScholar Bonney ENVELOPE(162.417,162.417,-77.717,-77.717) Fryxell ENVELOPE(163.183,163.183,-77.617,-77.617) Hoare ENVELOPE(162.850,162.850,-77.633,-77.633) McMurdo Dry Valleys Taylor Valley ENVELOPE(163.000,163.000,-77.617,-77.617) |
institution |
Open Polar |
collection |
Portland State University: PDXScholar |
op_collection_id |
ftportlandstate |
language |
English |
topic |
Meltwater -- Antarctica -- Taylor Valley Hydrologic models Lakes -- Antarctica -- Taylor Valley Geography Hydrology |
spellingShingle |
Meltwater -- Antarctica -- Taylor Valley Hydrologic models Lakes -- Antarctica -- Taylor Valley Geography Hydrology Cross, Julian Michael Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
topic_facet |
Meltwater -- Antarctica -- Taylor Valley Hydrologic models Lakes -- Antarctica -- Taylor Valley Geography Hydrology |
description |
The McMurdo Dry Valleys (MDV), the largest ice-free region (4,500 km2) in Antarctica, are a polar desert with an average annual temperature of -18ºC. In Taylor Valley, one of the MDV, closed-basin, perennially ice-covered lakes occupy the valley floor. Their water balance is controlled by inflow from glacial meltwater runoff and loss due to sublimation, making them sensitive indicators of climate. In this study, a physically-based model of glacier meltwater and lake ice sublimation is adapted to explain modern (1996 to 2013) lake-level variations. Meltwater model results were improved by the inclusion of MODIS remotely-sensed albedo measurements (E = 0.47; nRMSE = 0.73). After 2008 the meltwater model significantly under-predicted streamflow and only through decreasing albedo by -30% (equivalent to a decrease of -0.18 on average) did the results match observations (E = 0.79; nRMSE = 0.45). This study provides the first estimate of direct (unmeasured) glacier inflow to the lakes, 69%, 73% and 28%, and sublimation loss rates, 0.37 m yr-1, 0.24 m yr-1 and 0.16 m yr-1, for lakes Bonney, Hoare and Fryxell, respectively. Despite similar meltwater volumes entering lakes Bonney and Fryxell, the difference in basin hypsometry results in a much faster lake rise at Bonney from 2002-13. If future climate conditions match current (1996-2013) conditions, all lakes will rise through the end of the century. |
format |
Text |
author |
Cross, Julian Michael |
author_facet |
Cross, Julian Michael |
author_sort |
Cross, Julian Michael |
title |
Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
title_short |
Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
title_full |
Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
title_fullStr |
Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
title_full_unstemmed |
Glacial Meltwater Modeling to Simulate Lake Water Budget (1996-2013) in Taylor Valley, Antarctica |
title_sort |
glacial meltwater modeling to simulate lake water budget (1996-2013) in taylor valley, antarctica |
publisher |
PDXScholar |
publishDate |
2020 |
url |
https://pdxscholar.library.pdx.edu/open_access_etds/5364 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=6436&context=open_access_etds |
long_lat |
ENVELOPE(162.417,162.417,-77.717,-77.717) ENVELOPE(163.183,163.183,-77.617,-77.617) ENVELOPE(162.850,162.850,-77.633,-77.633) ENVELOPE(163.000,163.000,-77.617,-77.617) |
geographic |
Bonney Fryxell Hoare McMurdo Dry Valleys Taylor Valley |
geographic_facet |
Bonney Fryxell Hoare McMurdo Dry Valleys Taylor Valley |
genre |
Antarc* Antarctica McMurdo Dry Valleys polar desert |
genre_facet |
Antarc* Antarctica McMurdo Dry Valleys polar desert |
op_source |
Dissertations and Theses |
op_relation |
https://pdxscholar.library.pdx.edu/open_access_etds/5364 https://pdxscholar.library.pdx.edu/cgi/viewcontent.cgi?article=6436&context=open_access_etds |
op_rights |
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). |
_version_ |
1766256599104487424 |