@article {4758, title = {Patterns of interdisciplinary collaboration resemble biogeochemical relationships in the McMurdo Dry Valleys, Antarctica: A historical social network analysis of science, 1907{\textendash}2016}, journal = {Polar Research}, volume = {41}, year = {2022}, month = {04/2022}, pages = {8037}, abstract = {

Co-authorship networks can provide key insights into the production of scientific knowledge. This is particularly interesting in Antarctica, where most human activity relates to scientific research. Bibliometric studies of Antarctic science have provided a useful understanding of international and interdisciplinary collaboration, yet most research has focused on broad-scale analyses over recent time periods. Here, we take advantage of a \‘Goldilocks\’ opportunity in the McMurdo Dry Valleys, an internationally important region of Antarctica and the largest ice-free region on the continent. The McMurdo Dry Valleys have attracted continuous and diverse scientific activity since 1958. It is a geographically confined region with limited access, making it possible to evaluate the influence of specific events and individuals. We trace the history of environmental science in this region using bibliometrics and social network analysis. Our results show a marked shift in focus from the geosciences to the biosciences, which mirrors wider trends in the history of science. Collaboration among individuals and academic disciplines increased through time, and the most productive scientists in the network are also the most interdisciplinary. Patterns of collaboration among disciplines resemble the biogeochemical relationships among respective landscape features, raising interesting questions about the role of the material environment in the development of scientific networks in the region, and the dynamic interaction with socio-cultural and political factors. Our focused, historical approach adds nuance to broad-scale bibliometric studies and could be applied to understanding the dynamics of scientific research in other regions of Antarctica and elsewhere.

}, keywords = {LTER-MCM, critical physical geography, environmental history, history of science, science and technology studies, scientometrics, visual network analysis}, doi = {10.33265/polar.v41.8037}, url = {https://polarresearch.net/index.php/polar/article/view/8037}, author = {Chignell, Stephen M. and Howkins, Adrian and Gullett, Poppie and Andrew G Fountain} } @article {4643, title = {Long-term shifts in feedbacks among glacier surface change, melt generation, and runoff, McMurdo Dry Valleys, Antarctica}, journal = {Hydrological Processes}, year = {2021}, month = {07/2021}, abstract = {

Glaciers of the McMurdo Dry Valleys (MDVs) Antarctica are the main source of streamflow in this polar desert. Because summer air temperatures hover near 0\°C small changes in the energy balance strongly affect meltwater generation. Here we demonstrate that increased surface roughness, which alters the turbulent transfer of energy between the ice surface and atmosphere, yields a detectable increase in meltwater runoff. At low elevations on the glaciers, basin-like topography became significantly rougher over 13\ years between repeat lidar surveys, yielding greater melt. In contrast, the smoother ice at higher elevation exhibited no detectable change in roughness. We pose a conceptual model of the cycle of glacier surface change as a result of climate forcing whereby glacier surfaces transition from being dominated by sublimation to becoming increasingly melt-dominated, which is reversible under prolonged cool periods. This research advances our understanding of warm season effects on polar glaciers.

}, keywords = {LTER-MCM}, issn = {0885-6087}, doi = {10.1002/hyp.14292}, url = {https://onlinelibrary.wiley.com/doi/10.1002/hyp.14292}, author = {Bergstrom, Anna J. and Michael N. Gooseff and Andrew G Fountain and Hoffman, Matthew} } @article {4715, title = {Research sites get closer to field camps over time: Informing environmental management through a geospatial analysis of science in the McMurdo Dry Valleys, Antarctica}, journal = {PLOS ONE}, volume = {16}, year = {2021}, month = {11/2021}, pages = {e0257950}, abstract = {

As in many parts of the world, the management of environmental science research in Antarctica relies on cost-benefit analysis of negative environmental impact versus positive scientific gain. Several studies have examined the environmental impact of Antarctic field camps, but very little work looks at how the placement of these camps influences scientific research. In this study, we integrate bibliometrics, geospatial analysis, and historical research to understand the relationship between field camp placement and scientific production in the McMurdo Dry Valleys of East Antarctica. Our analysis of the scientific corpus from 1907\–2016 shows that, on average, research sites have become less dispersed and closer to field camps over time. Scientific output does not necessarily correspond to the number of field camps, and constructing a field camp does not always lead to a subsequent increase in research in the local area. Our results underscore the need to consider the complex historical and spatial relationships between field camps and research sites in environmental management decision-making in Antarctica and other protected areas.

}, keywords = {LTER-MCM}, doi = {10.1371/journal.pone.0257950}, url = {https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257950}, author = {Chignell, Stephen M. and Myers, Madeline and Howkins, Adrian and Andrew G Fountain} } @article {4438, title = {A digital archive of human activity in the McMurdo Dry Valleys, Antarctica}, journal = {Earth System Science Data}, volume = {12}, year = {2020}, month = {05/2020}, abstract = {

Over the last half century, the McMurdo Dry Valleys (MDV) of East Antarctica have become a globally important site for scientific research and environmental monitoring. Historical data can make important contributions to current research activities and environmental management in Antarctica but tend to be widely scattered and difficult to access. We address this need in the MDV by compiling over 5000 historical photographs, sketches, maps, oral interviews, publications, and other archival resources into an online digital archive. The data have been digitized and georeferenced using a standardized metadata structure, which enables intuitive searches and data discovery via an online interface. The ultimate aim of the archive is to create as comprehensive as possible a record of human activity in the MDV to support ongoing research, management, and conservation efforts. This is a valuable tool for scientists seeking to understand the dynamics of change in lakes, glaciers, and other physical systems, as well as humanistic inquiry into the history of the Southern Continent. In addition to providing benchmarks for understanding change over time, the data can help target field sampling for studies working under the assumption of a pristine landscape by enabling researchers to identify the date and extent of past human activities. The full database is accessible via a web browser-based interface hosted by the McMurdo Long Term Ecological Research site: http://mcmurdohistory.lternet.edu/ (last access: 5 May 2020). The complete metadata data for all resources in the database are also available at the Environmental Data Initiative: https://doi.org/10.6073/pasta/6744cb28a544fda827805db123d36557 (Howkins et al., 2019).

}, keywords = {LTER-MCM}, doi = {10.5194/essd-12-1117-2020}, url = {https://www.earth-syst-sci-data.net/12/1117/2020/}, author = {Howkins, Adrian and Chignell, Stephen M. and Gullett, Poppie and Andrew G Fountain and Brett, Melissa and Preciado, Evelin} } @mastersthesis {4451, title = {Glacial meltwater modeling to simulate lake water budget (1996-2013) in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2020}, month = {01/2020}, school = {Portland State University}, type = {masters}, address = {Portland, OR}, abstract = {

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 -18 ̊C. 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.

}, keywords = {LTER-MCM}, doi = {10.15760/etd.7237}, url = {https://archives.pdx.edu/ds/psu/30806}, author = {Cross, Julian M. and Andrew G Fountain} } @article {4079, title = {Drivers of solar radiation variability in the McMurdo Dry Valleys, Antarctica}, journal = {Scientific Reports}, volume = {8}, year = {2018}, month = {03/2018}, abstract = {

Annually averaged solar radiation in the McMurdo Dry Valleys, Antarctica has varied by over 20 W m\−2 during the past three decades; however, the drivers of this variability are unknown. Because small differences in radiation are important to water availability and ecosystem functioning in polar deserts, determining the causes are important to predictions of future desert processes. We examine the potential drivers of solar variability and systematically eliminate all but stratospheric sulfur dioxide. We argue that increases in stratospheric sulfur dioxide increase stratospheric aerosol optical depth\ and decrease solar intensity. Because of the polar location of the McMurdo Dry Valleys (77\–78\°S) and relatively long solar ray path through the stratosphere, terrestrial solar intensity is sensitive to small differences in stratospheric transmissivity. Important sources of sulfur dioxide include natural (wildfires and volcanic eruptions) and anthropogenic emission.

}, keywords = {LTER-MCM}, doi = {10.1038/s41598-018-23390-7}, url = {http://www.nature.com/articles/s41598-018-23390-7.pdf}, author = {Maciek K. Obryk and Andrew G Fountain and Peter T. Doran and W. Berry Lyons and Eastman, R.} } @inbook {4100, title = {The Climate of Snow and Ice as Boundary Condition for Microbial Life in Psychrophiles: From Biodiversity to Biotechnology}, year = {2017}, publisher = {Springer}, organization = {Springer}, edition = {2}, abstract = {

The microclimate and structure of snow and ice are a boundary condition as well as a matrix for a large spectrum of microbial life under alpine and polar conditions. Biological activity critically depends on the supply of energy, water and nutrients, with solar radiation as the prime source of energy, varying with latitude and altitude. The energy balance at the snow or ice surface provides the boundary condition for the fluxes of energy and water to the snow and ice, with important latitudinal differences from the temperate to the polar regions. The extreme situations of sunlit rocks surrounded by snow and the environment of Antarctic cryoconite holes, where ice, water, solar radiation and nutrients interact in particular ways, closes this review on ice and its effect on microbial life.

}, keywords = {LTER-MCM}, isbn = {978-3-319-57056-3}, doi = {10.1007/978-3-319-57057-010.1007/978-3-319-57057-0_1}, url = {http://link.springer.com/content/pdf/10.1007/978-3-319-57057-0}, author = {Kuhn, Michael and Andrew G Fountain}, editor = {R. Margesin} } @article {4022, title = {Decadal ecosystem response to an anomalous melt season in a polar desert in Antarctica}, journal = {Nature Ecology \& Evolution}, volume = {1}, year = {2017}, month = {09/2017}, pages = {1334-1338}, keywords = {LTER-MCM}, doi = {10.1038/s41559-017-0253-0}, url = {https://www.nature.com/articles/s41559-017-0253-0}, author = {Michael N. Gooseff and John E. Barrett and Byron Adams and Peter T. Doran and Andrew G Fountain and W. Berry Lyons and Diane M. McKnight and John C. Priscu and Eric R. Sokol and Cristina D. Takacs-Vesbach and Martijn L. Vandegehuchte and Ross A. Virginia and Diana H. Wall} } @article {4101, title = {High-resolution elevation mapping of the McMurdo Dry Valleys, Antarctica, and surrounding regions}, journal = {Earth System Science Data}, volume = {9}, year = {2017}, month = {07/2017}, pages = {435 - 443}, abstract = {

We present detailed surface elevation measurements for the McMurdo Dry Valleys, Antarctica derived from aerial lidar surveys flown in the austral summer of 2014\–2015 as part of an effort to understand geomorphic changes over the past decade. Lidar return density varied from 2 to \> 10 returns m\−2\ with an average of about 5 returns m\−2. Vertical and horizontal accuracies are estimated to be 7 and 3 cm, respectively. In addition to our intended targets, other ad hoc regions were also surveyed including the Pegasus flight facility and two regions on Ross Island, McMurdo Station, Scott Base (and surroundings), and the coastal margin between Cape Royds and Cape Evans. These data are included in this report and data release. The combined data are freely available at\ https://doi.org/10.5069/G9D50JX3.

}, keywords = {LTER-MCM}, doi = {10.5194/essd-9-435-2017}, url = {https://www.earth-syst-sci-data.net/9/435/2017/essd-9-435-2017.pdf}, author = {Andrew G Fountain and Fernandez-Diaz, Juan C. and Maciek K. Obryk and Joseph S. Levy and Michael N. Gooseff and David J. Van Horn and Morin, P and Shrestha, Ramesh} } @article {4032, title = {Impacts of permafrost degradation on a stream in Taylor Valley, Antarctica}, journal = {Geomorphology}, volume = {285}, year = {2017}, month = {05/2017}, pages = {205 - 213}, abstract = {

The McMurdo Dry Valleys (MDV) of Antarctica are an ice-free landscape that supports a complex, microbially dominated ecosystem despite a severely arid, cold environment (b 5 cm water equivalent/y, \− 18 \°C mean annual air temperature). Recent observations of permafrost degradation in the coastal zones of the MDV suggest that this region is nearing a threshold of rapid landscape change. In 2012, substantial thermokarst development was observed along several kilometers of the west branch of Crescent Stream in Taylor Valley mostly in the form of bank failures, whereas the adjacent east branch was unaffected. The objective of this study was to quantify the changes to the stream banks of the west branch of Crescent Stream and to determine the impacts on the composition of the stream bed material. Three annually repeated terrestrial LiDAR scans were compared to determine the rates of ground surface change caused by thermokarst formation on the stream bank. The areal extent of the thermokarst was shown to be decreasing; however, the average vertical rate of retreat remained constant. Field measurements of bed materials indicated that the west branch and the reach downstream of the confluence (of east and west branches) consistently contained more fines than the unaffected east branch. This suggests that the finer bed material is a result of the thermokarst development on the west branch. These finer bed material compositions are likely to increase the mobility of the bed material, which will have implications for stream morphology, stream algal mat communities, and downstream aquatic ecosystems.

}, keywords = {LTER-MCM}, doi = {10.1016/j.geomorph.2017.02.009}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0169555X16308467}, author = {Sudman, Zachary and Michael N. Gooseff and Andrew G Fountain and Joseph S. Levy and Maciek K. Obryk and David J. Van Horn} } @article {4020, title = {Glaciers in equilibrium, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {62}, year = {2016}, month = {07/2016}, pages = {976 - 989}, abstract = {

The McMurdo Dry Valleys are a cold, dry polar desert and the alpine glaciers therein exhibit small annual and seasonal mass balances, often \<\±0.06 m w.e. Typically, winter is the accumulation season, but significant snow storms can occur any time of year occasionally making summer the accumulation season. The yearly equilibrium line altitude is poorly correlated with mass balance because the elevation gradient of mass balance on each glacier can change dramatically from year to year. Most likely, winds redistribute the light snowfall disrupting the normal gradient of increasing mass balance with elevation. Reconstructed cumulative mass balance shows that the glaciers have lost \<2 m w.e. over the past half century and area changes show minimal retreat. In most cases these changes are less than the uncertainty and the glaciers are considered in equilibrium. Since 2000, however, the glaciers have lost mass despite relatively stable summer air temperatures suggesting a different mechanism in play. Whether this trend is a harbinger of future changes or a temporary excursion is unclear.

}, keywords = {LTER-MCM, Antarctica, glaciers, mass balance}, issn = {0022-1430}, doi = {10.1017/jog.2016.86}, url = {https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000861}, author = {Andrew G Fountain and Hassan J. Basagic and Niebuhr, Spencer} } @article {4102, title = {The Impact of a Large-Scale Climate Event on Antarctic Ecosystem Processes}, journal = {BioScience}, volume = {66}, year = {2016}, month = {10/2016}, pages = {848 - 863}, abstract = {

Extreme climate and weather events, such as a drought, hurricanes, or ice storms, can strongly imprint ecosystem processing and may alter ecosystem structure. Ecosystems in extreme environments are particularly vulnerable because of their adaptation to severe limitations in energy, water, or nutrients. The vulnerability can be expressed as a relatively long-lasting ecosystem response to a small or brief change in environmental conditions. Such an event occurred in Antarctica and affected two vastly different ecosystems: a marine-dominated coastal system and a terrestrial polar desert. Both sites experienced winds that warmed air temperatures above the 0\°C threshold, resulting in extensive snow and ice melt and triggering a series of cascading effects through the ecosystems that are continuing to play out more than a decade later. This highlights the sensitivity of Antarctic ecosystems to warming events, which should occur more frequently in the future with global climate warming.

}, keywords = {LTER-MCM}, issn = {0006-3568}, doi = {10.1093/biosci/biw110}, url = {http://academic.oup.com/bioscience/article-pdf/66/10/848/7510601/biw110.pdf}, author = {Andrew G Fountain and Saba, Grace and Byron Adams and Peter T. Doran and Fraser, William and Michael N. Gooseff and Maciek K. Obryk and John C. Priscu and Sharon E. Stammerjohn and Ross A. Virginia} } @article {3210, title = {Experimental formation of pore fluids in McMurdo Dry Valleys soils}, journal = {Antarctic Science}, volume = {27}, year = {2015}, month = {04/2015}, pages = {163 - 171}, abstract = {

The aim of the study was to determine if soil salt deliquescence and brine hydration can occur under laboratory conditions using natural McMurdo Dry Valleys soils. The experiment was a laboratory analogue for the formation of isolated patches of hypersaline, damp soil, referred to as \‘wet patches\’. Soils were oven dried and then hydrated in one of two humidity chambers: one at 100\% relative humidity and the second at 75\% relative humidity. Soil hydration is highly variable, and over the course of 20 days of hydration, ranged from increases in water content by mass from 0\–16\% for 122 soil samples from Taylor Valley. The rate and absolute amount of soil hydration correlates well with the soluble salt content of the soils but not with grain size distribution. This suggests that the formation of bulk pore waters in these soils is a consequence of salt deliquescence and hydration of the brine from atmospheric water vapour.

}, keywords = {LTER-MCM}, issn = {0954-1020}, doi = {10.1017/S0954102014000479}, url = {http://www.journals.cambridge.org/abstract_S0954102014000479}, author = {Joseph S. Levy and Andrew G Fountain and W. Berry Lyons and Kathleen A. Welch} } @article {3205, title = {Patterns and processes of salt efflorescences in the McMurdo region, Antarctica}, journal = {Artic, Antarctic and Alpine Research}, year = {2015}, abstract = {

Evaporite salts are abundant around the McMurdo region, Antarctica (~78\°S) due to very low precipitation, low relative humidity, and limited overland flow. Hygroscopic salts in the McMurdo Dry Valleys (MDVs) are preferentially formed in locations where liquid water is present in the austral summer, including along ephemeral streams, ice-covered lake boundaries, or shallow groundwater tracks. In this study, we collected salts from the Miers, Garwood, and Taylor Valleys on the Antarctic continent, as well as around McMurdo Station on Ross Island in close proximity to water sources with the goal of understanding salt geochemistry in relationship to the hydrology of the area. Halite is ubiquitous; sodium is the major cation (ranging from 70\%\–90\% of cations by meq kg\−1\ sediment) and chloride is the major anion (\>50\%) in nearly all samples. However, a wide variety of salt phases and morphologies are tentatively identified through scanning electron microscopy (SEM) and X-ray diffraction (XRD) work. We present new data that identifies trona (Na3(CO3)(HCO3)\·2H2O), tentative gaylussite (Na2Ca(CO3)2\·5H2O), and tentative glauberite (Na2Ca(SO4)2) in the MDV, of which the later one has not been documented previously. Our work allows for the evaluation of processes that influence brine evolution on a local scale, consequently informing assumptions underlying large-scale processes (such as paleoclimate) in the MDV. Hydrological modeling conducted in FREZCHEM and PHREEQC suggests that a model based on aerosol deposition alone in low elevations on the valley floor inadequately characterizes salt distributions found on the surfaces of the soil because it does not account for other hydrologic inputs/outputs. Implications for the salt distributions include their use as tracers for paleolake levels, geochemical tracers of ephemeral water tracks or \“wet patches\” in the soil, indicators of chemical weathering products, and potential delineators of ecological communities.

}, keywords = {LTER-MCM}, url = {http://aaarjournal.org/doi/abs/10.1657/AAAR0014-024}, author = {Bisson, K. M. and Kathleen A. Welch and Sue Welch and Sheets, J. M. and W. Berry Lyons and Joseph S. Levy and Andrew G Fountain} } @article {3209, title = {Hyperspectral measurements of wet, dry and saline soils from the McMurdo Dry Valleys: soil moisture properties from remote sensing}, journal = {Antarctic Science}, volume = {26}, year = {2014}, month = {10/2014}, pages = {565 - 572}, abstract = {

Soil moisture is a spatially heterogeneous quantity in the McMurdo Dry Valleys of Antarctica that exerts a large influence on the biological community and on the thermal state of Dry Valleys permafrost. The goal of this project was to determine whether hyperspectral remote sensing techniques could be used to determine soil moisture conditions in the Dry Valleys. We measured the spectral reflectance factors of wetted soil samples from the Dry Valleys under natural light conditions and related diagnostic spectral features to surface layer soil moisture content. Diagnostic water absorption features in the spectra at 1.4 \µm and 1.9 \µm were present in all samples, including samples doped with high concentrations of chloride salts. The depth of the 1.4 \µm absorption is shown to increase linearly with increasing gravimetric water content. These results suggest that airborne hyperspectral imaging of the Dry Valleys could generate soil moisture maps of this environment over large spatial areas using non-invasive remote-sensing techniques.

}, keywords = {LTER-MCM}, issn = {0954-1020}, doi = {10.1017/S0954102013000977}, url = {http://www.journals.cambridge.org/abstract_S0954102013000977}, author = {Joseph S. Levy and Nolin, Anne and Andrew G Fountain and Head, James W.} } @article {3202, title = {The McMurdo Dry Valleys: A landscape on the threshold of change}, journal = {Geomorphology}, volume = {225}, year = {2014}, month = {11/2014}, pages = {25 - 35}, abstract = {

Field observations of coastal and lowland regions in the McMurdo Dry Valleys suggest they are on the threshold of rapid topographic change, in contrast to the high elevation upland landscape that represents some of the lowest rates of surface change on Earth. A number of landscapes have undergone dramatic and unprecedented landscape changes over the past decade including, the Wright Lower Glacier (Wright Valley) \— ablated several tens of meters, the Garwood River (Garwood Valley) has incised \>\ 3\ m into massive ice permafrost, smaller streams in Taylor Valley (Crescent, Lawson, and Lost Seal Streams) have experienced extensive down-cutting and/or bank undercutting, and Canada Glacier (Taylor Valley) has formed sheer, \>\ 4\ meter deep canyons. The commonality between all these landscape changes appears to be sediment on ice acting as a catalyst for melting, including ice-cement permafrost thaw. We attribute these changes to increasing solar radiation over the past decade despite no significant trend in summer air temperature. To infer possible future landscape changes in the McMurdo Dry Valleys, due to anticipated climate warming, we map \‘at risk\’ landscapes defined as those with buried massive ice in relative warm regions of the valleys. Results show that large regions of the valley bottoms are \‘at risk\’. Changes in surface topography will trigger important responses in hydrology, geochemistry, and biological community structure and function.

}, keywords = {LTER-MCM}, issn = {0169555X}, doi = {10.1016/j.geomorph.2014.03.044}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0169555X14001780http://api.elsevier.com/content/article/PII:S0169555X14001780?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0169555X14001780?httpAccept=text/plain}, author = {Andrew G Fountain and Joseph S. Levy and Michael N. Gooseff and David J. Van Horn} } @article {1068, title = {Near-Surface Internal Melting - a Substantial Mass Loss on Antarctic Dry Valley Glaciers.}, journal = {Journal of Glaciology}, volume = {60}, year = {2014}, month = {04/2014}, pages = {361-374}, chapter = {361}, abstract = {The McMurdo Dry Valleys, southern Victoria Land, East Antarctica, are a polar desert, and melt from glacial ice is the primary source of water to streams, lakes and associated ecosystems. Previous work found that to adequately model glacier ablation and subsurface ice temperatures with a surface energy-balance model required including the transmission of solar radiation into the ice. Here we investigate the contribution of subsurface melt to the mass balance of (and runoff from) Dry Valley glaciers by including a drainage process in the model and applying the model to three glacier sites using 13years of hourly meteorological data. Model results for the smooth glacier surfaces common to many glaciers in the Dry Valleys showed that sublimation was typically the largest component of surface lowering, with rare episodes of surface melting, consistent with anecdotal field observations. Results also showed extensive internal melting 5-15 cm below the ice surface, the drainage of which accounted for 50\% of summer ablation. This is consistent with field observations of subsurface streams and formation of a weathering crust. We identify an annual cycle of weathering crust formation in summer and its removal during the 10 months of winter sublimation.}, keywords = {LTER-MCM}, doi = {10.3189/2014JoG13J095}, author = {Hoffman, M and Andrew G Fountain and Liston, G} } @article {3206, title = {Spring thaw ionic pulses boost nutrient availability and microbial growth in entombed Antarctic Dry Valley cryoconite holes}, journal = {Frontiers in Microbiology}, volume = {5}, year = {2014}, month = {12/2014}, abstract = {

The seasonal melting of ice entombed cryoconite holes on McMurdo Dry Valley glaciers provides oases for life in the harsh environmental conditions of the polar desert where surface air temperatures only occasionally exceed 0\°C during the Austral summer. Here we follow temporal changes in cryoconite hole biogeochemistry on Canada Glacier from fully frozen conditions through the initial stages of spring thaw toward fully melted holes. The cryoconite holes had a mean isolation age from the glacial drainage system of 3.4 years, with an increasing mass of aqueous nutrients (dissolved organic carbon, total nitrogen, total phosphorus) with longer isolation age. During the initial melt there was a mean nine times enrichment in dissolved chloride relative to mean concentrations of the initial frozen holes indicative of an ionic pulse, with similar mean nine times enrichments in nitrite, ammonium, and dissolved organic matter. Nitrate was enriched twelve times and dissolved organic nitrogen six times, suggesting net nitrification, while lower enrichments for dissolved organic phosphorus and phosphate were consistent with net microbial phosphorus uptake. Rates of bacterial production were significantly elevated during the ionic pulse, likely due to the increased nutrient availability. There was no concomitant increase in photosynthesis rates, with a net depletion of dissolved inorganic carbon suggesting inorganic carbon limitation. Potential nitrogen fixation was detected in fully melted holes where it could be an important source of nitrogen to support microbial growth, but not during the ionic pulse where nitrogen availability was higher. This study demonstrates that ionic pulses significantly alter the timing and magnitude of microbial activity within entombed cryoconite holes, and adds credence to hypotheses that ionic enrichments during freeze-thaw can elevate rates of microbial growth and activity in other icy habitats, such as ice veins and subglacial regelation zones

}, keywords = {LTER-MCM}, doi = {10.3389/fmicb.2014.00694}, url = {http://journal.frontiersin.org/article/10.3389/fmicb.2014.00694/abstract}, author = {Telling, J. and Alexandre M. Anesio and Martyn Tranter and Andrew G Fountain and Thomas H. Nylen and Hawkings, Jon and Singh, Virendra B. and Kaur, Preeti and Musilova, Michaela and Wadham, J. L.} } @article {1091, title = {Accelerated thermokarst formation in the McMurdo Dry Valleys, Antarctica}, journal = {Scientific Reports}, volume = {3}, year = {2013}, month = {07/2013}, keywords = {LTER-MCM}, doi = {10.1038/srep02269}, url = {http://www.nature.com/srep/2013/130724/srep02269/full/srep02269.html?WT.ec_id=SREP-20130730}, author = {Joseph S. Levy and Andrew G Fountain and Dickson, James L. and Head, James W. and Okal, Marianne and Marchant, David R. and Watters, Jaclyn} } @article {1082, title = {Do Cryoconite Holes have the Potential to be Significant Sources of C, N, and P to Downstream Depauperate Ecosystems of Taylor Valley, Antarctica?}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {45}, year = {2013}, month = {11/2013}, pages = {440 - 454}, keywords = {LTER-MCM}, doi = {10.1657/1938-4246-45.4.440}, author = {Bagshaw, Elizabeth and Martyn Tranter and Andrew G Fountain and Kathleen A. Welch and Hassan J. Basagic and W. Berry Lyons} } @article {1079, title = {Environmental factors influencing diatom communities in Antarctic cryoconite holes}, journal = {Environmental Research Letters}, volume = {8}, year = {2013}, month = {12/2013}, pages = {045006}, keywords = {LTER-MCM}, doi = {10.1088/1748-9326/8/4/045006}, url = {http://iopscience.iop.org/1748-9326/8/4/045006/pdf/1748-9326_8_4_045006.pdf}, author = {Lee F. Stanish and Bagshaw, Elizabeth and Diane M. McKnight and Andrew G Fountain and Martyn Tranter} } @article {1086, title = {Garwood Valley, Antarctica: A new record of Last Glacial Maximum to Holocene glaciofluvial processes in the McMurdo Dry Valleys}, journal = {Geological Society of America Bulletin}, volume = {125}, year = {2013}, month = {09/2013}, pages = {1484 - 1502}, keywords = {LTER-MCM}, doi = {10.1130/B30783.1}, url = {http://bulletin.geoscienceworld.org/content/early/2013/06/07/B30783.1.abstract}, author = {Joseph S. Levy and Andrew G Fountain and O{\textquoteright}Connor, J. E. and Kathleen A. Welch and W. Berry Lyons} } @article {1100, title = {Water track modification of soil ecosystems in the Lake Hoare basin, Taylor Valley, Antarctica}, journal = {Antarctic Science}, year = {2013}, pages = {1 - 10}, keywords = {LTER-MCM}, doi = {10.1017/S095410201300045X}, author = {Joseph S. Levy and Andrew G Fountain and Michael N. Gooseff and John E. Barrett and Robert Vantreese and Kathleen A. Welch and W. Berry Lyons and Uffe N. Nielsen and Diana H. Wall} } @article {1101, title = {Aeolian flux of biotic and abiotic material in Taylor Valley, Antarctica}, journal = {Geomorphology}, volume = {155-156}, year = {2012}, month = {6/2012}, pages = {102 - 111}, keywords = {LTER-MCM}, doi = {10.1016/j.geomorph.2011.12.009}, url = {http://www.sciencedirect.com/science/article/pii/S0169555X11006222}, author = {Marie {\v S}aback{\'a} and John C. Priscu and Hassan J. Basagic and Andrew G Fountain and Diana H. Wall and Ross A. Virginia and Mark C. Greenwood} } @article {1119, title = {The Disappearing Cryosphere: Impacts and Ecosystem Responses to Rapid Cryosphere Loss}, journal = {BioScience}, volume = {62}, year = {2012}, month = {04/2012}, pages = {405 - 415}, keywords = {LTER-MCM}, doi = {10.1525/bio.2012.62.4.11}, url = {http://bioscience.oxfordjournals.org/content/62/4/405.full}, author = {Andrew G Fountain and John L. Campbell and Edward A. G. Schuur and Sharon E. Stammerjohn and Mark W. Williams and Hugh W. Ducklow} } @article {1121, title = {Hypersaline {\textquotedblleft}wet patches{\textquotedblright} in Taylor Valley, Antarctica}, journal = {Geophysical Research Letters}, volume = {39}, year = {2012}, month = {03/2012}, keywords = {LTER-MCM}, doi = {10.1029/2012GL050898}, author = {Joseph S. Levy and Andrew G Fountain and Kathleen A. Welch and W. Berry Lyons} } @article {4062, title = {Seismic multiplet response triggered by melt at Blood Falls, Taylor Glacier, Antarctica}, journal = {Journal of Geophysical Research: Earth Surface}, volume = {117}, year = {2012}, month = {07/2012}, abstract = {

Meltwater input often triggers a seismic response from glaciers and ice sheets. It is difficult, however, to measure melt production on glaciers directly, while subglacial water storage is not directly observable. Therefore, we document temporal changes in seismicity from a dry-based polar glacier (Taylor Glacier, Antarctica) during a melt season using a synthesis of seismic observation and melt modeling. We record icequakes using a dense six-receiver network of three-component geophones and compare this with melt input generated from a calibrated surface energy balance model. In the absence of modeled surface melt, we find that seismicity is well-described by a diurnal signal composed of microseismic events in lake and glacial ice. During melt events, the diurnal signal is suppressed and seismicity is instead characterized by large glacial icequakes. We perform network-based correlation and clustering analyses of seismic record sections and determine that 18\% of melt-season icequakes are repetitive (multiplets). The epicentral locations for these multiplets suggest that they are triggered by meltwater produced near a brine seep known as Blood Falls. Our observations of the correspondingp-wave first motions are consistent with volumetric source mechanisms. We suggest that surface melt enables a persistent pathway through this cold ice to an englacial fracture system that is responsible for brine release episodes from the Blood Falls seep. The scalar moments for these events suggest that the volumetric increase at the source region can be explained by melt input.

}, keywords = {LTER-MCM}, doi = {10.1029/2011JF002221}, url = {http://onlinelibrary.wiley.com/doi/10.1029/2011JF002221/full}, author = {Carmichael, J. D. and Pettit, E. and Hoffman, M and Andrew G Fountain and Hallet, B.} } @article {1140, title = {Determination of Dissolved Oxygen in the Cryosphere: A Comprehensive Laboratory and Field Evaluation of Fiber Optic Sensors}, journal = {Environmental Science \& Technology}, volume = {45}, year = {2011}, month = {01/2011}, pages = {700 - 705}, keywords = {LTER-MCM}, doi = {10.1021/es102571j}, author = {Bagshaw, Elizabeth and Wadham, J. L. and Mowlem, M. and Martyn Tranter and Eveness, J. and Andrew G Fountain and Telling, J.} } @article {1137, title = {High-resolution monitoring reveals dissolved oxygen dynamics in an Antarctic cryoconite hole}, journal = {Hydrological Processes}, volume = {25}, year = {2011}, month = {08/2011}, pages = {2868 - 2877}, keywords = {LTER-MCM}, doi = {10.1002/hyp.8049}, author = {Bagshaw, Elizabeth and Martyn Tranter and Wadham, J. L. and Andrew G Fountain and Mowlem, M.} } @article {1135, title = {Hydrological Connectivity of the Landscape of the McMurdo Dry Valleys, Antarctica}, journal = {Geography Compass}, volume = {5}, year = {2011}, month = {09/2011}, pages = {666 - 681}, keywords = {LTER-MCM}, doi = {10.1111/j.1749-8198.2011.00445.x}, url = {http://onlinelibrary.wiley.com/doi/10.1111/j.1749-8198.2011.00445.x}, author = {Michael N. Gooseff and Diane M. McKnight and Peter T. Doran and Andrew G Fountain and W. Berry Lyons} } @article {1133, title = {Water tracks and permafrost in Taylor Valley, Antarctica: Extensive and shallow groundwater connectivity in a cold desert ecosystem}, journal = {Geological Society of America Bulletin}, volume = {123}, year = {2011}, month = {11/2011}, pages = {2295-2311}, keywords = {LTER-MCM}, doi = {10.1130/B30436.1}, url = {http://bulletin.geoscienceworld.org/content/123/11-12/2295.short}, author = {Joseph S. Levy and Andrew G Fountain and Michael N. Gooseff and Kathleen A. Welch and W. Berry Lyons} } @article {1151, title = {Antarctic lakes suggest millennial reorganizations of Southern Hemisphere atmospheric and oceanic circulation}, journal = {Proceedings of the National Academy of Sciences}, volume = {107}, year = {2010}, month = {12/2010}, pages = {21355 - 21359}, keywords = {LTER-MCM}, doi = {10.1073/pnas.1007250107}, url = {http://www.pnas.org/content/107/50/21355.full.pdf$\#$page=1\&view=FitH}, author = {Brenda L. Hall and George H. Denton and Andrew G Fountain and Chris H. Hendy and Gideon M. Henderson} } @inbook {1169, title = {The biogeochemistry and hydrology of Dry Valley glaciers: is there life on Martian ice now?}, booktitle = {Life in Antarctic Deserts and other Cold Dry Environments}, year = {2010}, pages = {195-220}, publisher = {Cambridge University Press}, organization = {Cambridge University Press}, address = {Cambridge}, keywords = {LTER-MCM}, author = {Martyn Tranter and Bagshaw, Elizabeth and Andrew G Fountain and Forman, C.} } @article {1162, title = {Dynamic behaviour of supraglacial lakes on cold polar glaciers: Canada Glacier, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {56}, year = {2010}, month = {06/2010}, pages = {366 - 368}, keywords = {LTER-MCM}, doi = {10.3189/002214310791968449}, author = {Bagshaw, Elizabeth and Martyn Tranter and Wadham, J. L. and Andrew G Fountain and Hassan J. Basagic} } @article {1165, title = {A dynamic physical model for soil temperature and water in Taylor Valley, Antarctica.}, journal = {Antarctic Science}, year = {2010}, month = {05/13/2010}, pages = {419-434}, type = {Journal}, keywords = {LTER-MCM}, doi = {10.1017/S0954102010000234}, author = {H. W. Hunt and Andrew G Fountain and Peter T. Doran and Hassan J. Basagic} } @mastersthesis {1230, title = {An Energy Balance Model of Melt-water Production for Polar Glaciers in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2010}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ebnet, J and Andrew G Fountain} } @article {1147, title = {Experimentally increased snow accumulation alters soil moisture and animal community structure in a polar desert}, journal = {Polar Biology}, volume = {33}, year = {2010}, month = {7/2010}, pages = {897 - 907}, keywords = {LTER-MCM}, doi = {10.1007/s00300-010-0766-3}, author = {Edward Ayres and Johnson N. Nkem and Diana H. Wall and Byron Adams and John E. Barrett and Breana L. Simmons and Ross A. Virginia and Andrew G Fountain} } @article {1166, title = {Snow in the McMurdo Dry Valleys, Antarctica.}, journal = {International Journal of Climatology}, volume = {30}, year = {2010}, month = {04/2010}, pages = {633-642}, type = {Journal}, abstract = {

Snowfall was measured at 11 sites in the McMurdo Dry Valleys to determine its magnitude, its temporal changes, and spatial patterns. Annual values ranged from 3 to 50 mm water equivalent with the highest values nearest the coast and decreasing inland. A particularly strong spatial gradient exists in Taylor Valley, probably resulting from local uplift conditions at the coastal margin and valley topography that limits migration inland. More snow occurs in winter near the coast, whereas inland no seasonal pattern is discernable. This may be due, again, to local uplift conditions, which are common in winter. We find no influence of the distance to the sea ice edge. Katabatic winds play an important role in transporting snow to the valley bottoms and essentially double the precipitation. That much of the snow accumulation sublimates prior to making a hydrologic contribution underscores the notion that the McMurdo Dry Valleys are indeed an extreme polar desert. Copyright \© 2009 Royal Meteorological Society

}, keywords = {LTER-MCM, Biggie}, doi = {10.1002/joc.1933}, author = {Andrew G Fountain and Thomas H. Nylen and Andrew Monaghan and Hassan J. Basagic and David Bromwich} } @inbook {1213, title = {Glacial ecosystems}, booktitle = {Ecological Monographs}, volume = {78}, year = {2008}, pages = {41-67}, edition = {1}, abstract = {
There is now compelling evidence that microbially mediated reactions impart a significant effect upon the dynamics, composition, and abundance of nutrients in glacial melt water. Consequently, we must now consider ice masses as ecosystem habitats in their own right and address their diversity, functional potential, and activity as part of alpine and polar environments. Although such research is already underway, its fragmentary nature provides little basis for developing modern concepts of glacier ecology. This paper therefore provides a much-needed framework for development by reviewing the physical, biogeochemical, and microbiological characteristics of microbial habitats that have been identified within glaciers and ice sheets. Two key glacial ecosystems emerge, one inhabiting the glacier surface (the supraglacial ecosystem) and one at the ice-bed interface (the subglacial ecosystem). The supraglacial ecosystem is characterized by a diverse consortium of microbes (usually bacteria, algae, phytoflagellates, fungi, viruses and occasional rotifers, tardigrades, and diatoms) within the snowpack, supraglacial streams, and melt pools (cryoconite holes). The subglacial system is dominated by aerobic/anaerobic bacteria and most probably viruses in basal ice/till mixtures and subglacial lakes. A third, so-called englacial ecosystem is also described, but it is demonstrated that conditions within glacier ice are sufficient to make metabolic activity and its impact upon nutrient dynamics negligible at the glacier scale.
Consideration of the surface and internal heat balances of the glacier show that all glacial ecosystems are sensitive to climate change, although at different timescales. Thus, while rapid, melt-driven habitat changes lead to melt-out, resuscitation, and redistribution of microorganisms in many supraglacial ecosystems, much slower climatic and glacial mass-balance processes effect such changes in the subglacial ecosystem. Paradoxically, it is shown that these forces have brought about net refreezing and the onset of cryostasis in the subglacial ecosystems of many Arctic glaciers subject to thinning in recent decades.
}, keywords = {LTER-MCM, Biggie, snow ecology}, doi = {10.1890/07-0187.1}, url = {http://dx.doi.org/10.1890/07-0187.1}, author = {Hodson, A and Alexandre M. Anesio and Martyn Tranter and Andrew G Fountain and Osborn, M and John C. Priscu and Johanna Laybourn-Parry and Sattler, B} } @article {1204, title = {Hydrologic response to extreme warm and cold summers in the McMurdo Dry Valleys, East Antarctica}, journal = {Antarctic Science}, volume = {20}, year = {2008}, month = {05/16/2008}, pages = {499-509}, type = {Journal}, keywords = {LTER-MCM, Climate Response, streams}, doi = {10.1017/S0954102008001272}, author = {Peter T. Doran and Christopher P. McKay and Andrew G Fountain and Thomas H. Nylen and Diane M. McKnight and Chris Jaros and John E. Barrett} } @inbook {1215, title = {Ice-based freshwater ecosystems}, booktitle = {Polar Lakes and Rivers: Limnology of Arctic and Antarctic Aquatic Ecosystems}, year = {2008}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {Oxford}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ian Hawes and Clive Howard-Williams and Andrew G Fountain}, editor = {Warwick F. Vincent and Johanna Laybourn-Parry} } @article {1217, title = {Introduction - The Biogeochemistry of Cryoconite Holes}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2008}, keywords = {LTER-MCM}, doi = {10.1029/2008JG000698}, author = {Andrew G Fountain and Martyn Tranter} } @article {1226, title = {Surface energy balance and melt thresholds over 11 years at Taylor Glacier, Antarctica}, journal = {Journal of Geophysical Research-Earth Surface}, volume = {113}, year = {2008}, keywords = {LTER-MCM}, doi = {10.1029/2008JF001029}, author = {Hoffman, M and Andrew G Fountain and Liston, G} } @article {1227, title = {Temporal variations in physical and chemical features of cryoconite holes on Canada Glacier, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2008}, pages = {G01S92}, keywords = {LTER-MCM}, doi = {10.1029/2008JG000698}, author = {Andrew G Fountain and Thomas H. Nylen and Martyn Tranter and Bagshaw, Elizabeth} } @article {1239, title = {The biogeochemical evolution of cryoconite holes on glaciers in Taylor Valley, Antarctica}, journal = {Journal of Geophysical Research}, volume = {113}, year = {2007}, pages = {G04S35}, keywords = {LTER-MCM}, doi = {LTER}, author = {Bagshaw, Elizabeth and Martyn Tranter and Andrew G Fountain and Kathleen A. Welch and Hassan J. Basagic and W. Berry Lyons} } @article {1236, title = {Biogeochemical stoichiometry of Antarctic Dry Valley ecosystems}, journal = {Journal of Geophysical Research}, volume = {112}, year = {2007}, month = {02/2007}, pages = {G01010+12}, abstract = {

Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P to nutrient concentrations in proportions far above or below ratios necessary to support balanced microbial growth. This polar desert provides an opportunity to evaluate stoichiometric approaches to understand nutrient cycling in an ecosystem where biological diversity and activity are low, and controls over the movement and mass balances of nutrients operate over 10\–106\ years. The simple organisms (microbial and metazoan) comprising dry valley foodwebs adhere to strict biochemical requirements in the composition of their biomass, and when activated by availability of liquid water, they influence the chemical composition of their environment according to these ratios. Nitrogen and phosphorus varied significantly in terrestrial and aquatic ecosystems occurring on landscape surfaces across a wide range of exposure ages, indicating strong influences of landscape development and geochemistry on nutrient availability. Biota control the elemental ratio of stream waters, while geochemical stoichiometry (e.g., weathering, atmospheric deposition) evidently limits the distribution of soil invertebrates. We present a conceptual model describing transformations across dry valley landscapes facilitated by exchanges of liquid water and biotic processing of dissolved nutrients. We conclude that contemporary ecosystem stoichiometry of Antarctic Dry Valley soils, glaciers, streams, and lakes results from a combination of extant biological processes superimposed on a legacy of landscape processes and previous climates.

}, keywords = {LTER-MCM, Biggie}, doi = {10.1029/2005JG000141}, author = {John E. Barrett and Ross A. Virginia and W. Berry Lyons and Diane M. McKnight and John C. Priscu and Andrew G Fountain and Diana H. Wall and Daryl L. Moorhead and Peter T. Doran} } @article {1237, title = {Solute and isotope geochemistry of subsurface ice melt seeps in Taylor Valley, Antarctica}, journal = {Geological Society of America Bulletin}, volume = {119}, year = {2007}, month = {01/2007}, pages = {548-555}, keywords = {LTER-MCM, Climate Response}, doi = {10.1130/B25913.1}, url = {http://gsabulletin.gsapubs.org/content/119/5-6/548.short}, author = {Harris, K and Anne E. Carey and Kathleen A. Welch and W. Berry Lyons and Andrew G Fountain} } @article {1259, title = {The aeolian flux of calcium, chloride and nitrate to the McMurdo Dry Valleys landscape: Evidence from snow pit analysis}, journal = {Antarctic Science}, volume = {18}, year = {2006}, pages = {497-505}, keywords = {LTER-MCM}, doi = {LTER}, author = {Witherow, R and Bertler, N and Kathleen A. Welch and W. Berry Lyons and Paul A. Mayewski and Sneed, S and Thomas H. Nylen and Handley, M and Andrew G Fountain} } @article {1267, title = {Experimental investigations into processes controlling stream and hyporheic temperatures, Fryxell Basin, Antarctica}, journal = {Advances in Water Resources}, volume = {29}, year = {2006}, pages = {130-153}, keywords = {LTER-MCM}, doi = {LTER}, author = {Cozzetto, K and Diane M. McKnight and Thomas H. Nylen and Andrew G Fountain} } @article {1270, title = {Glacier mass balances (1993-2001) Taylor Valley, McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {52}, year = {2006}, pages = {451}, keywords = {LTER-MCM}, doi = {LTER}, author = {Andrew G Fountain and Thomas H. Nylen and MacClune, K and Gayle L. Dana} } @article {1258, title = {A stable isotopic investigation of a polar desert hydrologic system, McMurdo Dry Valleys, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {38}, year = {2006}, month = {02/2006}, pages = {60-71}, keywords = {LTER-MCM}, doi = {10.1657/1523-0430(2006)038[0060:ASIIOA]2.0.CO;2}, author = {Michael N. Gooseff and W. Berry Lyons and Diane M. McKnight and Bruce H. Vaughn and Andrew G Fountain and Carolyn Dowling} } @article {1292, title = {The chemical composition of runoff from Canada Glacier, Antarctica: implications for glacier hydrology during a cool summer}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {15-19}, keywords = {LTER-MCM}, doi = {LTER}, author = {Martyn Tranter and Andrew G Fountain and W. Berry Lyons and Thomas H. Nylen and Kathleen A. Welch} } @article {1293, title = {Comment on {\textquoteleft}{\textquoteleft}El Ni{\~n}o suppresses Antarctic warming{\textquoteright}{\textquoteright} by N. Bertler et al.}, journal = {Geophysical Research Letters}, volume = {32}, year = {2005}, pages = {L07706}, keywords = {LTER-MCM, Tropical meteorology}, doi = {10.1029/2004GL021716}, author = {Peter T. Doran and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons and John C. Priscu and W. Berry Lyons and Walsh, J and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall} } @article {1294, title = {Dating water and solute additions to ice-covered Antarctic lakes}, journal = {Geochimica et Cosmochimica Acta}, volume = {69}, year = {2005}, pages = {A720}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Carolyn Dowling and Kathleen A. Welch and Snyder, G and Robert J. Poreda and Peter T. Doran and Andrew G Fountain} } @article {1297, title = {The Geochemistry of Supraglacial Streams of Canada Glacier, Taylor Valley (Antarctica), and their Evolution into Proglacial Waters}, journal = {Aquatic Geochemistry}, volume = {11}, year = {2005}, pages = {391-412}, keywords = {LTER-MCM}, author = {Sarah Fortner and Martyn Tranter and Andrew G Fountain and W. Berry Lyons and Kathleen A. Welch} } @article {1299, title = {Groundwater seeps in Taylor Valley Antarctica: An example of a subsurface melt event}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {200-206}, keywords = {LTER-MCM}, doi = {LTER}, author = {W. Berry Lyons and Kathleen A. Welch and Anne E. Carey and Diana H. Wall and Ross A. Virginia and Andrew G Fountain and Peter T. Doran and Csatho, B and Tremper, C} } @article {1290, title = {An index model of stream flow at below freezing-temperatures in Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, month = {01/2005}, pages = {76-82}, type = {Journal}, keywords = {LTER-MCM, Climate Response}, doi = {10.3189/172756405781813519}, url = {http://dx.doi.org/10.3189/172756405781813519}, author = {Ebnet, A and Andrew G Fountain and Thomas H. Nylen} } @article {1303, title = {The origin of channels on lower Taylor Glacier, McMurdo Dry Valleys Antarctica and their implication for water runoff}, journal = {Annals of Glaciology}, volume = {40}, year = {2005}, pages = {1-7}, keywords = {LTER-MCM}, doi = {LTER}, author = {Johnston, R and Andrew G Fountain and Thomas H. Nylen} } @article {1305, title = {Perturbation of hydrochemical conditions in natural microcosms entombed within Antarctic ice}, journal = {Ice and Climate News}, volume = {6}, year = {2005}, pages = {22-23}, keywords = {LTER-MCM}, author = {Martyn Tranter and Andrew G Fountain and Christian H. Fritsen and W. Berry Lyons and John C. Priscu and Stratham, P and Kathleen A. Welch} } @mastersthesis {1317, title = {A temperature-index model of stream flow in Taylor Valley, Antarctica}, volume = {M.S.}, year = {2005}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Ebnet, A} } @article {1323, title = {The Biodiversity and Biogeochemistry of Cryoconite Holes from McMurdo Dry Valley Glaciers, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {36}, year = {2004}, pages = {84-91}, keywords = {LTER-MCM}, author = {Porazinska, D and Andrew G Fountain and Thomas H. Nylen and Martyn Tranter and Ross A. Virginia and Diana H. Wall} } @article {1318, title = {Can warming induce advances of polar glaciers, Taylor Valley, Antarctica}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, month = {12/2004}, pages = {556-564}, keywords = {LTER-MCM}, doi = {10.3189/172756504781829701}, author = {Andrew G Fountain and Thomas A. Neumann and Paul L. Glenn and Trevor Chinn} } @article {1326, title = {Climatology of Katabatic Winds in the McMurdo Dry Valleys, Southern Victoria Land, Antarctica}, journal = {Journal of Geophysical Research}, volume = {109}, year = {2004}, keywords = {LTER-MCM}, author = {Thomas H. Nylen and Andrew G Fountain and Peter T. Doran} } @article {1327, title = {Cryoconite holes on polar glaciers and their importance for meltwater runoff}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, pages = {25-45}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Martyn Tranter and Thomas H. Nylen and Booth, D and Karen J. Lewis} } @mastersthesis {1350, title = {Development of large supraglacial channels in the polar environment}, volume = {M.S.}, year = {2004}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Johnston, R} } @article {1321, title = {Evolution of cryoconite holes and their contribution to meltwater runoff from glaciers in the McMurdo Dry Valleys, Antarctica}, journal = {Journal of Glaciology}, volume = {50}, year = {2004}, month = {01/2004}, pages = {35-45}, keywords = {LTER-MCM}, doi = {10.3189/172756504781830312}, author = {Andrew G Fountain and Martyn Tranter and Thomas H. Nylen and Karen J. Lewis and Derek R. Mueller} } @article {1331, title = {Extreme hydrochemical conditions in natural microcosms entombed within Antarctic ice.}, journal = {Hydrological Processes}, volume = {18}, year = {2004}, pages = {379-387}, keywords = {LTER-MCM}, author = {Martyn Tranter and Andrew G Fountain and Christian H. Fritsen and W. Berry Lyons and John C. Priscu and Stathan, P and Kathleen A. Welch} } @inbook {1359, title = {Century to millennial scale climate change and ecosystem response in Taylor Valley, Antarctica}, booktitle = {Climate Variability and Ecosystem Response at Long-Term Ecological Research Sites}, series = {Long-Term Ecological Research Network}, year = {2003}, pages = {319-340}, publisher = {Oxford University Press}, organization = {Oxford University Press}, address = {New York City}, keywords = {LTER-MCM, Climate Response}, isbn = {0195150597}, author = {Andrew G Fountain and W. Berry Lyons}, editor = {D. Greenland and D. G. Goodin and R. C. Smith} } @article {1364, title = {Glaciers of the McMurdo Dry Valleys: terrestrial analog for Martian polar sublimation}, journal = {Journal of Geophysical Research}, volume = {108}, year = {2003}, pages = {5031}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Kargel, J and MacAyeal, D} } @article {1365, title = {Map-based methods for estimating glacier equilibrium-line altitudes}, journal = {Journal of Glaciology}, volume = {49}, year = {2003}, pages = {329-336}, keywords = {LTER-MCM}, doi = {LTER}, author = {Leonard, K and Andrew G Fountain} } @article {1369, title = {Surface glaciochemistry of Taylor Valley, southern Victoria Land, Antarctica and its relationship to stream chemistry.}, journal = {Hydrological Processes}, volume = {17}, year = {2003}, pages = {115-130}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Kathleen A. Welch and Andrew G Fountain and Gayle L. Dana and Bruce H. Vaughn and Diane M. McKnight} } @article {1377, title = {Antarctic climate cooling and terrestrial ecosystem response}, journal = {Nature}, volume = {415}, year = {2002}, month = {01/2002}, pages = {517-520}, type = {Journal}, keywords = {LTER-MCM, Climate Response}, doi = {10.1038/nature710}, author = {Peter T. Doran and John C. Priscu and W. Berry Lyons and John E. Walsh and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons} } @article {1382, title = {Recent Temperature Trends in the Antarctic}, journal = {Nature}, volume = {418}, year = {2002}, pages = {291-292}, keywords = {LTER-MCM}, author = {John E. Walsh and Gary D. Clow and Christian H. Fritsen and Christopher P. McKay and Andrew N. Parsons and Peter T. Doran and John C. Priscu and W. Berry Lyons and Andrew G Fountain and Diane M. McKnight and Daryl L. Moorhead and Ross A. Virginia and Diana H. Wall} } @article {1383, title = {Satellite-Derived Indices of Stream Discharge in Taylor Valley,Antarctica.}, journal = {Hydrological Processes}, volume = {16}, year = {2002}, pages = {1603-1616}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Davis, R and Andrew G Fountain and Robert A. Wharton Jr.} } @article {1376, title = {Snow patch influence on soil biogeochemical processes and invertebrate distribution in the McMurdo Dry Valleys, Antarctica}, journal = {Arctic, Antarctic, and Alpine Research}, volume = {35}, year = {2002}, month = {02/2003}, pages = {91-99}, type = {Journal}, keywords = {LTER-MCM, Biggie}, doi = {10.1657/1523-0430(2003)035[0091:SPIOSB]2.0.CO;2}, url = {http://instaar.metapress.com/content/r086455ju7213711/}, author = {Michael N. Gooseff and John E. Barrett and Peter T. Doran and Andrew G Fountain and W. Berry Lyons and Andrew N. Parsons and Porazinska, D and Ross A. Virginia and Diana H. Wall} } @article {1384, title = {Synthetic aperture radar detection of the snowline on Commonwealth and Howard Glaciers, Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {34}, year = {2002}, pages = {177-183}, keywords = {LTER-MCM}, author = {Bardel, P and Andrew G Fountain and Hall, D and Kwok, R} } @article {1374, title = {Valley floor climate observations from the McMurdo Dry Valleys, Antarctica, 1986-2000}, journal = {Journal of Geophysical Research}, volume = {107}, year = {2002}, month = {12/2002}, pages = {4772-4784}, type = {Journal}, abstract = {

Climate observations from the McMurdo dry valleys, East Antarctica are presented from a network of seven valley floor automatic meteorological stations during the period 1986 to 2000. Mean annual temperatures ranged from \−14.8\°C to \−30.0\°C, depending on the site and period of measurement. Mean annual relative humidity is generally highest near the coast. Mean annual wind speed increases with proximity to the polar plateau. Site-to-site variation in mean annual solar flux and PAR is due to exposure of each station and changes over time are likely related to changes in cloudiness. During the nonsummer months, strong katabatic winds are frequent at some sites and infrequent at others, creating large variation in mean annual temperature owing to the warming effect of the winds. Katabatic wind exposure appears to be controlled to a large degree by the presence of colder air in the region that collects at low points and keeps the warm less dense katabatic flow from the ground. The strong influence of katabatic winds makes prediction of relative mean annual temperature based on geographical position (elevation and distance from the coast) alone, not possible. During the summer months, onshore winds dominate and warm as they progress through the valleys creating a strong linear relationship (r2\ = 0.992) of increasing potential temperature with distance from the coast (0.09\°C km\−1). In contrast to mean annual temperature, summer temperature lends itself quite well to model predictions, and is used to construct a statistical model for predicting summer dry valley temperatures at unmonitored sites.

}, keywords = {LTER-MCM, Biggie}, doi = {10.1029/2001JD002045}, author = {Peter T. Doran and Christopher P. McKay and Gary D. Clow and Gayle L. Dana and Andrew G Fountain and Thomas H. Nylen and W. Berry Lyons} } @phdthesis {1415, title = {Energy balance of a rough glacier surface, Canada Glacier, McMurdo Dry Valleys, Antarctica}, volume = {Ph.D.}, year = {2001}, school = {Portland State University}, type = {doctoral}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis} } @mastersthesis {1420, title = {Synthetic aperture radar imagery of polar glaciers}, volume = {M.S.}, year = {2001}, school = {Portland State University}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Bardel, P} } @inbook {1426, title = {Climate and hydrologic variations and implications for lake and stream ecological response in the McMurdo Dry Valleys, Antarctica}, booktitle = {Climate Variability and Ecosystem Response at Long Term Ecological Research Sites}, year = {2000}, pages = {174-195}, publisher = {Oxford University Press}, organization = {Oxford University Press}, keywords = {LTER-MCM}, author = {Kathleen A. Welch and W. Berry Lyons and Diane M. McKnight and Chris Jaros and Andrew G Fountain and Thomas H. Nylen and Peter T. Doran and Clive Howard-Williams}, editor = {D. Greenland and D. G. Goodin and R. C. Smith} } @article {1432, title = {The importance of landscape position and legacy: The evolution of the Taylor Valley Lake District, Antarctica.}, journal = {Freshwater Biology}, volume = {43}, year = {2000}, pages = {355-367}, keywords = {LTER-MCM}, author = {W. Berry Lyons and Andrew G Fountain and Peter T. Doran and John C. Priscu and Klaus Neumann and Kathleen A. Welch} } @article {1461, title = {The importance of terminus cliff melt on stream flow, Taylor Valley, McMurdo Dry Valleys}, journal = {Global and Planetary Change}, volume = {22}, year = {1999}, pages = {105-115}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis and Andrew G Fountain and Paul Langevin} } @article {1447, title = {Physical controls on the Taylor Valley Ecosystem, Antarctica}, journal = {BioScience}, volume = {49}, year = {1999}, month = {12/1999}, pages = {961-972}, type = {Journal}, keywords = {LTER-MCM, Water availability}, author = {Andrew G Fountain and W. Berry Lyons and Melody B. Burkins and Gayle L. Dana and Peter T. Doran and Karen J. Lewis and Diane M. McKnight and Daryl L. Moorhead and Andrew N. Parsons and John C. Priscu and Diana H. Wall and Robert A. Wharton Jr. and Ross A. Virginia} } @article {1495, title = {Energy balance studies of Canada Glacier, Taylor Valley, McMurdo Dry Valleys, Antarctica}, journal = {Annals of Glaciology}, volume = {27}, year = {1998}, pages = {603-609}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis and Andrew G Fountain and Gayle L. Dana} } @inbook {1500, title = {Glaciers of the McMurdo Dry Valleys, Southern Victoria Land, Antarctica}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {65-75}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Gayle L. Dana and Karen J. Lewis and Bruce H. Vaughn and Diane M. McKnight} } @inbook {1501, title = {Hydrologic Processes Influencing Streamflow Variation in Fryxell Basin, Antarctica}, booktitle = {Ecosystem Processes in a Polar Desert: The McMurdo Dry Valleys, Antarctica}, series = {Antarctic Research Series}, volume = {72}, year = {1998}, pages = {93-108}, keywords = {LTER-MCM}, author = {Peter A. Conovitz and Diane M. McKnight and Lee H. MacDonald and Andrew G Fountain}, editor = {Harold R. House} } @article {1512, title = {McMurdo Dry Valleys LTER: Solar radiation on glaciers in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {191-193}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Robert A. Wharton Jr. and Andrew G Fountain} } @article {1513, title = {McMurdo Dry Valleys LTER: Spatial variation of glacier mass balance in Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {194-195}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Karen J. Lewis and Gayle L. Dana} } @article {1514, title = {McMurdo Dry Valleys LTER: The role of terminus cliff melt in streamflow, Taylor Valley, Antarctica}, journal = {Antarctic Journal of the United States - 1996 Review Issue (NSF 98-28)}, volume = {31}, year = {1998}, pages = {189-190}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Paul Langevin} } @article {1533, title = {Surface energy balance and meltwater production for a Dry Valley glacier, Taylor Valley, Antarctica}, journal = {Annals of Glaciology}, volume = {27}, year = {1998}, pages = {603-609}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Andrew G Fountain and Gayle L. Dana} } @inbook {1439, title = {A Temperature area index of stream discharge in Taylor Valley, Antarctica}, booktitle = {Applications of Remote Sensing in Hydrology}, year = {1998}, pages = {29-39}, publisher = {National Water Research Institute , Environment Canada}, organization = {National Water Research Institute , Environment Canada}, keywords = {LTER-MCM}, author = {Gayle L. Dana and Davis, R and Andrew G Fountain and Robert A. Wharton Jr.}, editor = {A. Pietroniro and R. Granger and T.J. Pultz} } @mastersthesis {1586, title = {Surface energy balance and meltwater production for a dry valley glacier, Taylor Valley, Antarctica}, volume = {M.S.}, year = {1996}, school = {University of Colorado}, type = {masters}, keywords = {LTER-MCM}, doi = {LTER}, author = {Karen J. Lewis} } @article {1595, title = {McMurdo LTER: The surface-energy balance of the Canada Glacier, Taylor Valley}, journal = {Antarctic Journal of the United States}, volume = {30}, year = {1995}, pages = {280-282}, keywords = {LTER-MCM}, author = {Karen J. Lewis and Gayle L. Dana and Scott W. Tyler and Andrew G Fountain} } @article {1616, title = {McMurdo LTER: Glacier mass balances of Taylor Valley, Antarctica}, journal = {Antarctic Journal of the U.S.}, volume = {29}, year = {1994}, pages = {226-228}, keywords = {LTER-MCM}, author = {Andrew G Fountain and Bruce H. Vaughn and Gayle L. Dana} } @inbook {1655, title = {Glaciers of the southern hemisphere}, booktitle = {Global and Planetary Change}, volume = {22}, year = {1990}, keywords = {LTER-MCM}, doi = {LTER}, author = {Andrew G Fountain} }