Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Institution
Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson
Uv-B Screening Potential Is Higher In Two Cosmopolitan Moss Species Than In A Co-Occurring Antarctic Endemic Moss – Implications Of Continuing Ozone Depletion, J. L. Dunn, Sharon A. Robinson
Faculty of Science - Papers (Archive)
Concentrations of UV-B absorbing pigments and anthocyanins were measured in three moss species, over a summer growing season in Antarctica. Pigment concentrations were compared with a range of climatic variables to determine if there was evidence that pigments were induced by UV-B radiation, or other environmental parameters, and secondly if there were differences between species in their pigment responses. Significant seasonal differences in the potential UV-B screening pigments were found, with the two cosmopolitan species Bryum pseudotriquetrum and Ceratodon purpureus appearing better protected from the potentially damaging effects of ozone depletion than the Antarctic endemic Schistidium antarctici. Bryum pseudotriquetrum accumulated …
Collaborative Research: Millennial-Scale Fluctuations Of Dry Valleys Lakes: Implications For Regional Climate Variability And The Interhemispheric (A)Synchrony Of Climate Change, Brenda Hall, Glenn Berger
Collaborative Research: Millennial-Scale Fluctuations Of Dry Valleys Lakes: Implications For Regional Climate Variability And The Interhemispheric (A)Synchrony Of Climate Change, Brenda Hall, Glenn Berger
University of Maine Office of Research Administration: Grant Reports
This award supports a project to add to the understanding of what drives glacial cycles. Most researchers agree that Milankovitch seasonal forcing paces the ice ages but how these insolation changes are leveraged into abrupt global climate change remains unknown. A current popular view is that the climate of Antarctica and the Southern Ocean leads that of the rest of the world by a couple thousand years at Termination I and by even greater margins during previous terminations. This project will integrate the geomorphological record of glacial history with a series of cores taken from the lake bottoms in the …
Some Like It Wet – Biological Characteristics Underpinning Tolerance Of Extreme Water Stress Events In Antarctic Bryophytes., J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Some Like It Wet – Biological Characteristics Underpinning Tolerance Of Extreme Water Stress Events In Antarctic Bryophytes., J. Wasley, Sharon A. Robinson, C. E. Lovelock, M. Popp
Faculty of Science - Papers (Archive)
Antarctic bryophyte communities presently tolerate physiological extremes in water availability, surviving both desiccation and submergence events. This study investigated the relative ability of three Antarctic moss species to tolerate physiological extremes in water availability and identified physiological, morphological, and biochemical characteristics that assist species performance under such conditions. Tolerance of desiccation and submergence was investigated using chlorophyll fluorescence during a series of field- and laboratory-based water stress events. Turf water retention and degree of natural habitat submergence were determined from gametophyte shoot size and density and ?13C signatures respectively. Finally, compounds likely to assist membrane structure and function during desiccation …
An Unusual Mesospheric Bore Event Observed At High Latitudes Over Antarctica, K. Nielsen, Michael J. Taylor, R G. Stockwell, M. J. Jarvis
An Unusual Mesospheric Bore Event Observed At High Latitudes Over Antarctica, K. Nielsen, Michael J. Taylor, R G. Stockwell, M. J. Jarvis
All Physics Faculty Publications
All-sky CCD observations of short-period mesospheric gravity waves have been made from Halley Station, Antarctica (76S, 27W). On 27 May, 2001, an unusual wave event exhibiting several features characteristic of a ‘‘bore’’ was observed in the OH, Na, and O2 nightglow emissions. Mesospheric bores are rare wave events that have previously been observed at mid- and low-latitudes. This event was particular interesting as: (1) it initially appeared as a single, high contrast, linear front, accompanied by a sharp enhancement in intensity in all three emissions, (2) a number of trailing wave crests were observed to form with a measured growth …
Iron In Ice Cores From Law Dome: A Record Of Atmospheric Iron Deposition For Maritime East Antarctica During The Holocene And Last Glacial Maximum, Ross Edwards, Peter N. Sedwick, Vin Morgan, Claude Boutron
Iron In Ice Cores From Law Dome: A Record Of Atmospheric Iron Deposition For Maritime East Antarctica During The Holocene And Last Glacial Maximum, Ross Edwards, Peter N. Sedwick, Vin Morgan, Claude Boutron
OES Faculty Publications
Total dissolvable iron (TDFe) was measured in sections of ice cores recovered from Law Dome on the coast of Wilkes Land, East Antarctica. These samples include ice dating from the Last Glacial Maximum (LGM), the Last Deglaciation, and the early and mid Holocene as well as samples from the Anthropocene that have been dated with seasonal to annual resolution. Combining our TDFe concentration data with estimates of the ice accumulation rate, we estimate the atmospheric iron deposition for Law Dome and the adjacent Southern Ocean during these periods. Our results indicate that the atmospheric iron deposition flux to this region …