Earth Sciences Commons^™

Vegetation Controls On Weathering Intensity During The Last Deglacial Transition In Southeast Africa, Sarah J. Ivory, Michael M. Mcglue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens

Earth and Environmental Sciences Faculty Publications

Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems behaved in the past and may alter in the future. We use high-resolution records of pollen, clay mineralogy, and particle size from a drill core from Lake Malawi, southeast Africa, to examine atmosphere-biosphere-geosphere interactions during the last deglaciation (~ 18-9 ka), a period of dramatic temperature and hydrologic changes. The …

Collaborative Research: Timing And Structure Of The Last Glacial Maximum And Termination In Southern Peru: Implications For The Role Of The Tropics In Climate Change, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

The role of the tropics in climate change has important implications for understanding both orbital-scale and abrupt climate variations. Yet our ability to assess tropical behavior during major climate events, such as the last glacial maximum (LGM), is limited by poor spatial coverage and insufficient control on sample ages. This project will address this problem by developing well-dated records of glacial fluctuations from the LGM through the termination and late-glacial period at Nevados Coropuna and Allinccapac in southern Peru and use these data in numerical simulations of glacier mass balance and local climate. These sites allow an examination of glacier …

Sensitivity Of The Antarctic Ice Sheet To Climate Change Over The Last Two Glacial/Interglacial Cycles, Brenda Hall, George H. Denton

University of Maine Office of Research Administration: Grant Reports

This project was designed to develop knowledge of the extent of the Ross Sea ice sheet during the last two glaciations and to develop a chronology for the last glacial maximum and penultimate glaciation. To this end, we had the following goals:

1) Map the extent of the Ross Sea ice sheet along the western coast of McMurdo Sound from Taylor Valley to the southern Royal Society Range.
2) Develop a radiocarbon chronology for the last glacial maximum from dates of algal mats within moraines.
3) Produce a uranium-thorium chronology to gain information on the timing of the penultimate glaciation. …

Sensitivity Of The Antarctic Ice Sheet To Climate Change Over The Last Two Glacial/Interglacial Cycles, Brenda L. Hall, George H. Denton

University of Maine Office of Research Administration: Grant Reports

This award supports a project to investigate the sensitivity of the Antarctic ice sheet (AIS) to global climate change over the last two Glacial/Interglacial cycles. The intellectual merit of the project is that despite its importance to Earth's climate system, we currently lack a full understanding of AIS sensitivity to global climate change. This project will reconstruct and precisely date the history of marine-based ice in the Ross Sea sector over the last two glacial/interglacial cycles, which will enable a better understanding of the potential driving mechanisms (i.e., sea-level rise, ice dynamics, ocean temperature variations) for ice fluctuations. This will …

Assessing The Impacts Of Climate Change, Urbanization, And Filter Strips On Water Quality Using Swat, Mike Psaris, Heejun Chang

International Journal of Geospatial and Environmental Research

Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess potential changes in stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA. We evaluate …

Hudson Museum Collection: Byrd's Second Antarctic Expedition, 1933-1935, John L. Herrman, Harold Borns

UMaine Video

Dr. Harold Borns, Professor Emeritus at the University of Maine Climate Change Institute, narrates original footage of Richard E. Byrd's second Antarctic expedition, 1933-1935. The footage was filmed by John L. Herrmann of Paramount Pictures. The original footage presented was transferred from 16mm film in January 2002 by Northeast Historic Film in Bucksport, Maine, and narration by Dr. Harold Borns added in August 2014. The original film footage is held by the Hudson Museum, University of Maine.

Changes In Tundra Plant And Soil Organic Geochemical Composition In Response To Long-Term Increased Winter Precipitation In N. Alaska, Olivia Miller

Open Access Theses

Tundra ecosystem soils store half of the global soil organic carbon (SOC) pool and have the potential to release large amounts of greenhouse gases, primarily CH₄ and CO₂. As climates warm and permafrost thaws, the emissions of these gases as organic matter decomposition rates increase may become increasingly important to the chemistry of the atmosphere. Increases in precipitation that accompany warming, may shift tundra vegetative composition from moss/graminoid- to shrub-dominated systems. These vegetation shifts may result in important feedback effects as altered plant and litter chemistry may affect SOC storage in soils. Questions investigated include: 1) How …

Wetlands On The Thousand Lake Mountain Mega-Landslide As Paleoclimate Proxies, Ryan Andros Shurtliff

Theses and Dissertations

The Windy Ridge mega-landslide in Wayne and Sevier Counties originated in Lates tPleistocene time as established by 14C ages on basal organic-rich clay and peat sediment from bogs that developed on the slide. The contact depth between bog and landslide was estimated using high-resolution seismic reflection to find the thickest sediment. Four bogs were cored at their depocenters, and organic material at the slide contact was used for age determinations. The oldest bog sediments ages are 10,600 ± 46, 10,556 ± 34, 12,511 ± 134, and 12,886 ± 91 calibrated years BP. Ages represent two sliding events. First, at the …

Collaborative Research: St. Elias Erosion And Tectonics Project (Steep), Peter O. Koons, Phaedra Upton

University of Maine Office of Research Administration: Grant Reports

1) Refinement of a regional scale model to include an approximation of the true 3D geometry of the orogen.

2) Develop a new local-scale model that incorporates topography, GPS data, and glacial erosion processes to refine the initial results.

3) Develop a modeling experiment to test the hypothesis that the rise and fall of ice masses during glacial cycles might influence where deformation is focused at any given time.

Colle Gnifetti Ice Core (Kcc) Progress Report (Year One)—Arcadia Ice Core Proposal: Initiatives On The Science Of The Human Past, Paul Mayewski

University of Maine Office of Research Administration: Grant Reports

The Colle Gnifetti glacier of the Monta Rosa Massif on the Swiss-Italian border is perfectly situated to offer insight into the intersection of environment (climate) and culture (history of the economy, political stability, pollution, disease) in medieval Europe. While ice cores previously collected at Colle Gnifetti were sampled at state-of-the-art resolution for the time, it was nevertheless impossible to differentiate annual or finer layering in the period older than 1500 A.D. The 2013 Colle Gnifetti expedition thus sought to collect a new ice core that could be analyzed using the ultra-high-resolution laser based technology developed in the Climate Change Institute’s …

Impact Of Climate Change On Wheat Production In Kentucky, Kathleen Russell, Chad Lee, Rebecca L. Mcculley, David Van Sanford

Plant and Soil Sciences Research Report

Summary:

• From 2002 to 2012, Kentucky winter wheat ranged in value from $52 million to $209 million.
• Climate change and variability have the potential to significantly impact this important economic enterprise within our state.
• This report summarizes the current state of knowledge of the potential of climate change to impact wheat production in Kentucky and surrounding states.

Wetland Issues Affecting Waterfowl Conservation In North America, Heath M. Hagy, Scott C. Yaich, John W. Simpson, Eduardo Carrera, David A. Haukos, W.Carter Johnson, Charles R. Loesch, Fritz A. Reid, Scott E. Stephens, Ralph W. Tiner, Brett A. Werner, Greg S. Yarris

Natural Resource Management Faculty Publications

This paper summarises discussions by invited speakers during a special session at the 6th North American Duck Symposium on wetland issues that affect waterfowl, highlighting current ecosystem challenges and opportunities for the conservation of waterfowl in North America. Climate change, invasive species, U.S. agricultural policy (which can encourage wetland drainage and the expansion of row-crop agriculture into grasslands), cost and competition for water rights, and wetland management for non-waterfowl species were all considered to pose significant threats to waterfowl populations in the near future. Waterfowl populations were found to be faced with significant threats in several regions, including: the Central …