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Full-Text Articles in Physical Sciences and Mathematics

Where To Find 1.5 Million Yr Old Ice For The Ipics "Oldest Ice" Ice Core, H. Fischer, J. Severinghaus, E. Brook, E. Wolff, M. Albert Nov 2013

Where To Find 1.5 Million Yr Old Ice For The Ipics "Oldest Ice" Ice Core, H. Fischer, J. Severinghaus, E. Brook, E. Wolff, M. Albert

Dartmouth Scholarship

Abstract. The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this pro- gression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic distur- bance and should be able to be recovered after careful pre- site selection studies. Based …


Exploring Greenhouse Gas Emissions From Beaver Ponds In Southern Rhode Island, Molly K. Welsh May 2013

Exploring Greenhouse Gas Emissions From Beaver Ponds In Southern Rhode Island, Molly K. Welsh

Senior Honors Projects

Climate change is one of the largest environmental issues facing humanity today, having the potential to alter fresh water availability, agricultural yields, forest productivity, and global sea levels. As climate change is likely to increase the intensity of extreme weather events, the potential for massive human and financial consequences is of further concern. The Intergovernmental Panel on Climate Change asserts that climate change is due to anthropogenic alterations of the atmosphere’s composition, with additional contributions from natural biochemical processes. In particular, the rapid increase in the concentrations of greenhouse gases (GHGs) in the atmosphere can trigger atmospheric warming as these …


Modeling Vulnerability Of Groundwater To Pollution Under Future Scenarios Of Climate Change And Biofuels-Related Land Use Change: A Case Study In North Dakota, Usa, Ruopu Li, James W. Merchant Mar 2013

Modeling Vulnerability Of Groundwater To Pollution Under Future Scenarios Of Climate Change And Biofuels-Related Land Use Change: A Case Study In North Dakota, Usa, Ruopu Li, James W. Merchant

School of Natural Resources: Faculty Publications

Modeling groundwater vulnerability to pollution is critical for implementing programs to protect groundwater quality.Most groundwater vulnerability modeling has been based on current hydrogeology and land use condi- tions. However, groundwater vulnerability is strongly dependent on factors such as depth-to-water, recharge and land use conditions thatmay change in response to future changes in climate and/or socio-economic condi- tions. In this research, a modeling framework, which employs three sets of models linked within a geographic information system (GIS) environment, was used to evaluate groundwater pollution risks under future climate and land use changes in North Dakota. The results showed that areas with …


Orbitally Paced Shifts In The Particle Size Of Antarctic Continental Shelf Sediments In Response To Ice Dynamics During The Miocene Climatic Optimum, Sandra Passchier, Candice J. Falk, Fabio Florindo Feb 2013

Orbitally Paced Shifts In The Particle Size Of Antarctic Continental Shelf Sediments In Response To Ice Dynamics During The Miocene Climatic Optimum, Sandra Passchier, Candice J. Falk, Fabio Florindo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The AND-2A drill hole (ANDRILL [Antarctic Geological Drilling Program] Southern McMurdo Sound Project), ∼10 km from the East Antarctica coastline, records nearly 6 m.y. of sedimentation across the Miocene climatic optimum at a high-latitude site. Sedimentological studies of bedforms and particle size distributions indicate that the paleoenvironment was strongly affected by waves and currents, consistent with deposition in a glacially influenced neritic environment. We document abrupt shifts in mud percent within glacial-interglacial cycles ca. 17.8 Ma and between ca. 16.7 and 15.7 Ma that we attribute to the hydrodynamic effects of wave stirring tied to episodes of ice growth and …


Water, Climate, And Social Change In A Fragile Landscape, William L. Hargrove, David M. Borrok, Josiah Mc C.C. Heyman, Craig E. Tweedie, Carlos Cabrera Ferregut Feb 2013

Water, Climate, And Social Change In A Fragile Landscape, William L. Hargrove, David M. Borrok, Josiah Mc C.C. Heyman, Craig E. Tweedie, Carlos Cabrera Ferregut

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

We present here and in the companion papers an analysis of sustainability in the Middle Rio Grande region of the U.S.-Mexico border and propose an interdisciplinary research agenda focused on the coupled human and natural dimensions of water resources sustainability in the face of climate and social change in an international border region. Key threats to water sustainability in the Middle Rio Grande River region include: (1) increasing salinization of surface and ground water, (2) increasing water demand from a growing population in the El Paso/Ciudad Juarez area on top of an already high base demand from irrigated agriculture, (3) …


Dynamic Diatom Response To Changing Climate 0-1.2 Ma At Lake El'gygytgyn, Far East Russian Arctic, Jeffrey Allan Snyder, M. V. Cheraponova, A. Bryan Jan 2013

Dynamic Diatom Response To Changing Climate 0-1.2 Ma At Lake El'gygytgyn, Far East Russian Arctic, Jeffrey Allan Snyder, M. V. Cheraponova, A. Bryan

School of Earth, Environment and Society Faculty Publications

The Lake El' gygytgyn sediment record contains an abundant diatom flora through most intervals of the lake's history, providing a means to create and test hypotheses concerning the lake's response to changing climates. The 0 1.2 Ma core interval is characterized by shifts in the dominant planktonic genera and events of exceptional concentration and diversity. Warm interglacial intervals have enhanced concentration and diversity of the plankton. This response is most extreme during exceptional events corresponding to marine isotope stages (MIS) 11 and 31. Diatom concentration and diversity also increase during some cold intervals (e.g., MIS 2), suggesting conditions of lake …


Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre Jan 2013

Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre

Daugherty Water for Food Global Institute: Faculty Publications

In 1950 the global population was just over 2.5 billion. Now, in 2013, it is around 7 billion. Although population growth is slowing, the world is projected to have around 9.6 billion inhabitants by 2050. Most of the population increase will be in developing countries where food is often scarce, and land and water are under pressure. To feed the global population in 2050 the world will have to produce more food without significantly expanding the area of cultivated land and, because of competition between a greater number of water users, with less freshwater. On top of land and water …


Ice-Age Megafauna In Arctic Alaska: Extinction, Invasion, Survival, Daniel H. Mann, Pamela Groves, Michael L. Kunz, Richard E. Reanier, Benjamin V. Gaglioti Jan 2013

Ice-Age Megafauna In Arctic Alaska: Extinction, Invasion, Survival, Daniel H. Mann, Pamela Groves, Michael L. Kunz, Richard E. Reanier, Benjamin V. Gaglioti

United States Geological Survey: Staff Publications

Radical restructuring of the terrestrial, large mammal fauna living in arctic Alaska occurred between 14,000 and 10,000 years ago at the end of the last ice age. Steppe bison, horse, and woolly mammoth became extinct, moose and humans invaded, while muskox and caribou persisted. The ice age mega fauna was more diverse in species and possibly contained 6x more individual animals than live in the region today. Mega faunal biomass during the last ice age may have been 30x greater than present. Horse was the dominant species in terms of number of individuals. Lions, short-faced bears, wolves, and possibly grizzly …


A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur Jan 2013

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …