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Centennial Eolian Cyclicity In The Great Plains, Usa: A Dominant Climate Pattern Of Wind Transport Over The Past 4000 Years?, Antje Schwalb, Walter E. Dean, Sherilyn C. Fritz, Christoph E. Geiss, Bernd Kromer 2010 Technische Universität Braunschweig

Centennial Eolian Cyclicity In The Great Plains, Usa: A Dominant Climate Pattern Of Wind Transport Over The Past 4000 Years?, Antje Schwalb, Walter E. Dean, Sherilyn C. Fritz, Christoph E. Geiss, Bernd Kromer

Papers in the Earth and Atmospheric Sciences

Proxy evidence at decadal resolution from Late Holocene sediments from Pickerel Lake, northeastern South Dakota, shows distinct centennial cycles (400-700 years) in magnetic susceptibility; contents of carbonate, organic carbon, and major elements; abundance in ostracodes; and δ18O and δ13C values in calcite. Proxies indicate cyclic changes in eolian input, productivity, and temperature. Maxima in magnetic susceptibility are accompanied by maxima in aluminum and iron mass accumulation rates (MARs), and in abundances of the ostracode Fabaeformiscandona rawsoni. This indicates variable windy, and dry conditions with westerly wind dominance, including during the Medieval Climate Anomaly. Maxima in carbonates ...


Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens 2010 University of Nebraska-Lincoln

Millennial-Scale Climate Variability During The Last Glacial Period In The Tropical Andes, Sherilyn C. Fritz, P. A. Baker, E. Ekdahl, G. O. Seltzer, L. R. Stevens

Papers in the Earth and Atmospheric Sciences

Millennial-scale climate variation during the Last Glacial period is evident in many locations worldwide, but it is unclear if such variation occurred in the interior of tropical South America, and, if so, how the low-latitude variation was related to its high-latitude counterpart. A high-resolution record, derived from the deep drilling of sediments on the floor of Lake Titicaca in the southern tropical Andes, is presented that shows clear evidence of millennial-scale climate variation between ~60 and 20 ka BP. This variation is manifested by alternations of two interbedded sedimentary units. The two units have distinctive sedimentary, geochemical, and paleobiotic properties ...


Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren 2010 Brown University

Climatic And Environmental Controls On The Occurrence And Distributions Of Long Chain Alkenones In Lakes Of The Interior United States, Jaime L. Toney, Yongsong Huang, Sherilyn C. Fritz, Paul A. Baker, Eric Grimm, Paul Nyren

Papers in the Earth and Atmospheric Sciences

Long chain alkenones (LCA) are temperature-sensitive lipids with great potential for quantitative reconstruction of past continental climate. We conducted the first survey for alkenone biomarkers from 55 different lakes in the Northern Great Plains and Nebraska Sand Hills of the United States. Among those surveyed, we found 13 lakes that contain LCAs in the surface sediments. The highest concentrations of alkenones in sediments are found in cold (mean annual air temperature ~11 °C versus 17 °C in our warmest sites), brackish to mesosaline (salinity = 8.5–9.7 g/L), and alkaline (pH = 8.4–9.0) lakes with high ...


Groundwater Recharge In Natural Dune Systems And Agricultural Ecosystems In The Thar Desert Region, Rajasthan, India, Bridget Scanlon, Abhijit Mukherjee, John B. Gates, Robert C. Reedy, Amarendra K. Sinha 2010 University of Texas at Austin

Groundwater Recharge In Natural Dune Systems And Agricultural Ecosystems In The Thar Desert Region, Rajasthan, India, Bridget Scanlon, Abhijit Mukherjee, John B. Gates, Robert C. Reedy, Amarendra K. Sinha

Papers in the Earth and Atmospheric Sciences

Water and nutrient availability for crop production are critical issues in (semi)arid regions. Unsaturated-zone Cl tracer data and nutrient (NO3 and PO4) concentrations were used to quantify recharge rates using the Cl mass balance approach and nutrient availability in the Thar Desert, Rajasthan, India. Soil cores were collected in dune/interdune settings in the arid Thar Desert (near Jaisalmer) and in rain-fed (nonirrigated) and irrigated cropland in the semiarid desert margin (near Jaipur). Recharge rates were also simulated using unsaturated zone modeling. Recharge rates in sparsely vegetated dune/interdune settings in the Jaisalmer study area are 2 ...


Inferring Lake Depth Using Diatom Assemblages In The Shallow, Seasonally Variable Lakes Of The Nebraska Sand Hills (Usa): Calibration, Validation, And Application Of A 69-Lake Training Set, Avery L. C. Shinneman, Danuta M. Bennett, Sherilyn C. Fritz, Jens Schmieder, Daniel R. Engstrom, Aris Efting, John Holz 2010 University of Nebraska–Lincoln

Inferring Lake Depth Using Diatom Assemblages In The Shallow, Seasonally Variable Lakes Of The Nebraska Sand Hills (Usa): Calibration, Validation, And Application Of A 69-Lake Training Set, Avery L. C. Shinneman, Danuta M. Bennett, Sherilyn C. Fritz, Jens Schmieder, Daniel R. Engstrom, Aris Efting, John Holz

Papers in the Earth and Atmospheric Sciences

The Nebraska Sand Hills are a distinctive eco-region in the semi-arid Great Plains of the western United States. The water table underlying the Sand Hills is part of the High Plains/ Ogallala aquifer, an important water resource for the central Great Plains. Lake levels are affected directly by fluctuations in the water table, which is recharged primarily by local precipitation and responds quickly to climatically induced changes in regional water balance. Instrumental records are available for only 50–100 years, and paleolimnological data provide important insights into the extremes and variability in moisture balance over longer time scales. A set ...


Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack 2010 University of Nebraska-Lincoln

Stratigraphic Signature Of The Late Palaeozoic Ice Age In The Parmeener Supergroup Of Tasmania, Se Australia, And Inter-Regional Comparisons, Christopher R. Fielding, Tracy D. Frank, John L. Isbell, Lindsey C. Henry, Eugene W. Domack

Papers in the Earth and Atmospheric Sciences

Recent research in eastern Australia has established that rather than being a single, long-lived epoch, the late Palaeozoic Ice Age comprised a series of glacial intervals each 1–8 million years in duration, separated by non-glacial intervals of comparable duration. In order to test whether the glacial events recognized in New South Wales and Queensland have broader extent, we conducted a reappraisal of the Parmeener Supergroup of Tasmania, southeast Australia. A facies analysis of the Pennsylvanian to Permian section was carried out, allowing rationalization of the succession into four recurrent facies associations: a) glacigenic facies association, restricted to the basal ...


Seasonal Hydrologic Trends In Iowa Watersheds Over The Last Half Of The 20th Century, Kayla Jo Conrad 2010 Iowa State University

Seasonal Hydrologic Trends In Iowa Watersheds Over The Last Half Of The 20th Century, Kayla Jo Conrad

Graduate Theses and Dissertations

Climate change is expected to cause significant changes in the global hydrologic cycle, yet the impact to regional hydrology is not well known for the Midwest U.S. As a first step in understanding the impact of climate change in Iowa watersheds, historical streamflow observations and model-derived time series of soil moisture, frozen ground and snow cover for ten Iowa watersheds were analyzed. The modeled data were generated using precipitation and temperature data spanning 1948 to 2003 as inputs to the conceptually-based hydrologic models of the National Weather Service river forecasting system. The models were calibrated for each watershed using ...


A Dynamic Physical Model For Soil Temperature And Water In Taylor Valley, Antarctica, H. W. Hunt, Andrew G. Fountain, Peter T. Doran, Hassan J. Basagic 2010 Colorado State University - Fort Collins

A Dynamic Physical Model For Soil Temperature And Water In Taylor Valley, Antarctica, H. W. Hunt, Andrew G. Fountain, Peter T. Doran, Hassan J. Basagic

Geography Faculty Publications and Presentations

We developed a simulation model for terrestrial sites including sensible heat exchange between the atmosphere and ground surface, inter- and intra-layer heat conduction by rock and soil, and shortwave and longwave radiation. Water fluxes included snowmelt, freezing/thawing of soil water, soil capillary flow, and vapour flows among atmosphere, soil, and snow. The model accounted for 96-99% of variation in soil temperature data. No long-term temporal trends in soil temperature were apparent. Soil water vapour concentration in thawed surface soil in summer often was higher than in frozen deeper soils, leading to downward vapour fluxes. Katabatic winds caused a reversal ...


Combined Effects Of Heat Waves And Droughts On Avian Communities Across The Conterminous United States, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Brian D. Wardlow, Curtis H. Flather, Patrick D. Culbert, Volker C. Radeloff 2010 University of Wisconsin-Madison

Combined Effects Of Heat Waves And Droughts On Avian Communities Across The Conterminous United States, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Brian D. Wardlow, Curtis H. Flather, Patrick D. Culbert, Volker C. Radeloff

Drought Mitigation Center Faculty Publications

Increasing surface temperatures and climatic variability associated with global climate change are expected to produce more frequent and intense heat waves and droughts in many parts of the world. Our goal was to elucidate the fundamental, but poorly understood, effects of these extreme weather events on avian communities across the conterminous United States. Specifically, we explored: (1) the effects of timing and duration of heat and drought events, (2) the effects of jointly occurring drought and heat waves relative to these events occurring in isolation, and (3) how effects vary among functional groups related to nest location and migratory habit ...


Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff 2010 University of Wisconsin-Madison

Effects Of Drought On Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Brian D. Wardlows, Volker C. Radeloff

Drought Mitigation Center Faculty Publications

Droughts are expected to become more frequent under global climate change. Avifauna depend on precipitation for hydration, cover, and food. While there are indications that avian communities respond negatively to drought, little is known about the response of birds with differing functional and behavioral traits, what time periods and indicators of drought are most relevant, or how response varies geographically at broad spatial scales. Our goals were thus to determine (1) how avian abundance and species richness are related to drought, (2) whether community variations are more related to vegetation vigor or precipitation deviations and at what time periods relationships ...


Mined-Over Matter, Judy McIlrath 2010 University of South Florida

Mined-Over Matter, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

No abstract provided.


Glacier (?) National Park, Judy McIlrath 2010 University of South Florida

Glacier (?) National Park, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

In this Spreadsheets Across the Curriculum activity, students examine data pertaining to the disappearing glaciers in Glacier National Park. After calculating percentage change of the number of glaciers from 1850 (150) to 1968 (50) and 2009 (26), they move on to the main glacier-monitoring content of the module--area vs. time data for the Grinnell Glacier, one of 26 glaciers that remain in the park. Using a second-order polynomial (quadratic function) fitted to the data, they extrapolate to estimate when there will be no Grinnell Glacier remaining (illustrating the relevance of the question mark in the title of the module). Introductory ...


Yellowstone! A National Park On A Hot Spot, Judy McIlrath 2010 University of South Florida

Yellowstone! A National Park On A Hot Spot, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

This Spreadsheets Across the Curriculum activity introduces Geology of National Parks students to Yellowstone National Park. The module takes a broad overview of volcanic features of the park, including the line of calderas along the up-drift hot spot trace, the mapped area of tuffs produced by their cataclysmic eruptions, and the hydrothermal features for which the park is so well known. Students calculate the rate that the North American Plate has been moving over the hot spot, the relative volume of the materials produced in the cataclysmic eruptions, their recurrence interval, and probability of eruption in any given year. The ...


Planning The Future Of Geocybereducation, Jeffrey G. Ryan, Susan Eriksson 2010 University of South Florida

Planning The Future Of Geocybereducation, Jeffrey G. Ryan, Susan Eriksson

Geology Faculty Publications

No abstract provided.


Geophysical Analysis Of Seasonal Montandon Gravel Ridge Water Table Fluctuation And Moisture Gradient Variation Due To Storm Events, Annie Strader 2010 Bucknell University

Geophysical Analysis Of Seasonal Montandon Gravel Ridge Water Table Fluctuation And Moisture Gradient Variation Due To Storm Events, Annie Strader

Honors Theses

The purpose of this research project is to continue exploring the Montandon Long-Term Hydrologic Research Site(LTHR) by using multiple geophysical methods to obtain more accurate and precise information regarding subsurface hydrologic properties of a local gravel ridge,which are important to both the health of surrounding ecosystems and local agriculture. Through using non-invasive geophysical methods such as seismic refraction, Direct Current resistivity and ground penetrating radar (GPR) instead of invasive methods such as boreholedrilling which displace sediment and may alter water flow, data collection is less likely to bias the data itself. In addition to imaging the gravel ridge ...


Higher-Order Physic For Modeling Ice Streams In Ice Sheets, Debra A. Kenneway 2010 The University of Maine

Higher-Order Physic For Modeling Ice Streams In Ice Sheets, Debra A. Kenneway

Electronic Theses and Dissertations

Ice streams are transitional between inland glaciers and ice shelves. Hence no stresses can be neglected. Ice streams are important dynamic features of a glacier; it is well known that ice streams drain up to 90% of the ice from an ice sheet. Herein I model ice streams as a multiphysics system of coupled components. This includes treating ice as a non-Newtonian fluid since empirical measurements show a power law relation between stress and strain rate. Sliding is a physical feature that must be included. This is done with a novel approach to sliding by way of a slippery layer ...


Climate Investigations Using Ice Sheet And Mass Balance Models With Emphasis On North American Glaciation, Sean David Birkel 2010 The University of Maine

Climate Investigations Using Ice Sheet And Mass Balance Models With Emphasis On North American Glaciation, Sean David Birkel

Electronic Theses and Dissertations

This dissertation describes the application of the University of Maine Ice Sheet Model (UM-ISM) and Environmental Change Model (UM-ECM) to understanding mechanisms of ice-sheet/climate integration during ice ages. The UM-ECM, written by the author for this research, calculates equilibrium biome and snow/ice mass balance solutions for the globe based on modern input climatology and user-defined parameter values. The program was produced in conjunction with a National Science Foundation ITEST grant meant to seed inquiry-based classroom study of Earth systems using computer models. To that end, the UM-ECM serves as both a research and teaching tool. The model has ...


Droughtscape- Winter 2010, Kelly Smith 2010 University of Nebraska-Lincoln

Droughtscape- Winter 2010, Kelly Smith

Droughtscape, Quarterly Newsletter of NDMC, 2007-

USDM Forum Highlights

Drought Likely to Ease

Research Shows Birds Vulnerable to Drought

Drought Recedes in 2009

CA, TX Suffer Impacts from Ongoing Drought

NDMC Wishes Ryu Well

Conferees Pick SPI for Global Drought Index


Examining The Effects Of Climate Change And Urban Development On Water Demand: A Multi-Scale Analysis Of Future Water Demand In Hillsboro, Oregon, Lily House-Peters 2010 Portland State University

Examining The Effects Of Climate Change And Urban Development On Water Demand: A Multi-Scale Analysis Of Future Water Demand In Hillsboro, Oregon, Lily House-Peters

Dissertations and Theses

In the Portland, Oregon, metropolitan area, suburban cities such as Hillsboro are projected to grow as people seek affordable housing near a rapidly growing metropolis. This thesis examines the combined impact of'c1imate change and urban development on both neighborhood and municipal scale residential water demand in Hillsboro, Oregon. I use two models, a surface energy balance model, Local-scale Urban Meteorological Parameterization Scheme (LUMPS), and a system dynamics model, CCDomestic, to investigate changes in residential water demand in the 2040s at two distinct spatial scales, the neighborhood and the municipality. I calibrate and validate each model to the reference period ...


On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church 2010 Old Dominion University

On The Fractional Solubillity Of Copper In Marine Aerosols: Toxicity Of Aeolian Copper Revisited, Edward R. Sholkovitz, Peter N. Sedwick, Thomas M. Church

OEAS Faculty Publications

Paytan et al. (2009) argue that the atmospheric deposition of aerosols lead to copper concentrations that are potentially toxic to marine phytoplankton in a large area of tropical and subtropical North Atlantic Ocean. A key assumption in their model is that all marine aerosols (mineral dust and anthropogenic particles) have a high (40%) fractional solubility of copper. Our data show that the fractional solubility of copper for Saharan dust over the Sargasso Sea and Bermuda is significantly lower (1-7%). In contrast, anthropogenic aerosols with non-Saharan sources have significantly higher values (10-100%). Hence, the potential Cu toxicity in the tropical and ...


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