AAAR publishes peer-reviewed interdisciplinary papers including original research papers, short communications and review articles. Rapid environmental change occurring in cold regions today highlights the global importance of this research. The mission of Arctic, Antarctic, and Alpine Research (AAAR) is to advance understanding of cold region environments by publishing original scientific research from past, present and future high-latitude and mountain regions. Inter-annual comparisons of lake profiles suggest that lake waters are directly influenced by the isotopic composition and amount of stream flow during a season. Furthermore, the results show that lake waters directly reflect their glacial ice sources, despite fractionation during stream transport. ![]() In-stream enrichment occurs through direct evaporation fractionation from the channel and hyporheic exchange with isotopically enriched waters in the near-stream subsurface during transport from the glacial source to lake. These results demonstrate the importance of in-stream fractionation at the valley scale. Within the lake basins, glacial ice source waters are depleted by as much as $111\textperthousand \delta D$ and $20\textperthousand \delta^O$ compared to lake waters. Snow pack in glacial accumulation zones is heterogeneous, likely a result of varying storm sources (continental versus coastal), and, in general, snow pits, fresh snow samples, and glacier ice are more depleted than stream waters. At the valley scale, glacial ice, snow, stream, and lake waters become more depleted in δ D with increasing distance from McMurdo Sound (further inland). The three major Taylor Valley lakes are not connected to one another hydrologically, and their levels are maintained by glacial meltwater inflow and perennial ice-cover sublimation. This data set provides a survey of the distribution of natural water isotope abundances within the well-defined dry valley hydrologic system in Taylor Valley, which extends 20 km inland from McMurdo Sound. During the austral summers from 00 to 2002-2003, fresh snow, snow pits, glacier ice, stream water, and lake waters were sampled for the stable isotopes deuterium (D) and 18O in order to resolve sources of meltwater and the interactions among the various hydrologic reservoirs in the dry valleys. ![]() The hydrologic system of the coastal McMurdo Dry Valleys, Antarctica, is defined by snow accumulation, glacier melt, stream flow, and retention in closed-basin, ice-covered lakes.
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