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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Climate From The Mcmurdo Dry Valleys, Antarctica, 1986–2017: Surface Air Temperature Trends And Redefined Summer Season, Maciej K. Obryk, Peter T. Doran, Andrew G. Fountain, M. Myers, Christopher P. Mckay May 2020

Climate From The Mcmurdo Dry Valleys, Antarctica, 1986–2017: Surface Air Temperature Trends And Redefined Summer Season, Maciej K. Obryk, Peter T. Doran, Andrew G. Fountain, M. Myers, Christopher P. Mckay

Geology Faculty Publications and Presentations

The weather of the McMurdo Dry Valleys, Antarctica, the largest ice‐free region of the Antarctica, has been continuously monitored since 1985 with currently 14 operational meteorological stations distributed throughout the valleys. Because climate is based on a 30‐year record of weather, this is the first study to truly define the contemporary climate of the McMurdo Dry Valleys. Mean air temperature and solar radiation based on all stations were −20°C and 102 Wm−2, respectively. Depending on the site location, the mean annual air temperatures on the valleys floors ranged between −15°C and −30°C, and mean annual solar radiation varied …


Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer Jan 2020

Deuterium Excess And 17o-Excess Variability In Meteoric Water Across The Pacific Northwest, Usa, John Bershaw, Dougal Hansen, Andrew Schauer

Geology Faculty Publications and Presentations

High-precision triple oxygen isotope analysis of water has given rise to a novel second-order parameter, 17O-excess (often denoted as δ17O), which describes the deviation from a reference relationship between δ18O and δ17O. This tracer, like deuterium excess (d-excess), is affected by kinetic fractionation (diffusion) during phase changes within the hydrologic cycle. However, unlike d-excess, 17O-excess is present in paleowater proxy minerals and is not thought to vary significantly with temperature. This makes it a promising tool in paleoclimate research, particularly in relatively arid continental regions where traditional approaches have produced equivocal results. …


Controls On Deuterium Excess Across Asia, John Bershaw Jul 2018

Controls On Deuterium Excess Across Asia, John Bershaw

Geology Faculty Publications and Presentations

Deuterium excess (d-excess) is a second-order stable isotope parameter measured in meteoric water to understand both the source of precipitation and the evolution of moisture during transport. However, the interpretation of d-excess patterns in precipitation is often ambiguous, as changes in moisture source and processes during vapor transport both affect d-excess in non-unique ways. This is particularly true in Asia where continental moisture travels a long distance across diverse environments from unique moisture sources before falling as precipitation. Here, I analyzed published d-excess records from meteoric water throughout Asia to better characterize what influences d-excess values. I conclude that, (1) …


Environmental Factors Influencing Diatom Communities In Antarctic Cryoconite Holes, Lee F. Stanish, Elizabeth A. Bagshaw, Diane M. Mcknight, Andrew G. Fountain, Martyn Tranter Oct 2013

Environmental Factors Influencing Diatom Communities In Antarctic Cryoconite Holes, Lee F. Stanish, Elizabeth A. Bagshaw, Diane M. Mcknight, Andrew G. Fountain, Martyn Tranter

Geology Faculty Publications and Presentations

Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by an ice lid that prevents the exchange of material and gases with the surrounding atmosphere and aquatic environment. Diatoms have been documented in cryoconite holes, and recent findings suggest that these habitats may harbour a distinctive diatom flora compared to the surrounding aquatic environments. In this study, we examined diatom community composition in cryoconite holes and environmental correlates across three glaciers in Taylor Valley, Antarctica. The diatom communities were …


Impacts Of Predicted Global Sea-Level Rise On Oregon Beaches And Tidelands, Curt D. Peterson Jan 2013

Impacts Of Predicted Global Sea-Level Rise On Oregon Beaches And Tidelands, Curt D. Peterson

Geology Faculty Publications and Presentations

Forward by:

Phillip Johnson, Executive Director Oregon Shores Conservation Coalition

The Oregon Shores Conservation Coalition’s "Coastal Climate Change Adaptation Project" is under development as an experiment in grassroots organizing for adaptive planning for expected climate change impacts. Oregon Shores is a regional conservation group with a 40-year history of working to protect marine, shoreline, estuarine and other coastal habitats. The organization’s board and staff came to recognize that the likely effects of climate change—rising sea levels, more intensive storm surges, increased erosion, lower-river flooding, among others—would affect every aspect of the group’s work. Consequently, a new program, the Climate Action …


Seaside, Oregon, Tsunami Pilot Study : Modernization Of Fema Flood Hazard Maps, Frank I. González, Eric L. Geist, Costas Synolakis, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Bruce Jaffe, Jeff Johnson, Utku Kânoğlu, Harold O. Mofjeld, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Vasily V. Titov, Angie J. Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner Aug 2006

Seaside, Oregon, Tsunami Pilot Study : Modernization Of Fema Flood Hazard Maps, Frank I. González, Eric L. Geist, Costas Synolakis, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Bruce Jaffe, Jeff Johnson, Utku Kânoğlu, Harold O. Mofjeld, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Vasily V. Titov, Angie J. Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner

Geology Faculty Publications and Presentations

FEMA Flood Insurance Rate Map (FIRM) guidelines do not currently exist for conducting and incorporating tsunami hazard assessments that reflect the substantial advances in tsunami research achieved in the last two decades; this conclusion is the result of two FEMA-sponsored workshops and the associated Tsunami Focused Study (Chowdhury et al., 2005). Therefore, as part of FEMA's Map Modernization Program, a Tsunami Pilot Study was carried out in the Seaside/Gearhart, Oregon, area to develop an improved Probabilistic Tsunami Hazard Assessment (PTHA) methodology and to provide recommendations for improved tsunami hazard assessment guidelines. The Seaside area was chosen because it is typical …