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The University of Maine

1995

Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Damariscotta River Estuary: A Management Plan, Fran Rudoff, Jenny Ruffing, Tom Ford Dec 1995

Damariscotta River Estuary: A Management Plan, Fran Rudoff, Jenny Ruffing, Tom Ford

Documents from Environmental Organizations

One purpose ofthe Damariscotta River Estuary Project has been to ask and answer these and other questions. A second and equally important purpose ofthe Project has been to help the seven estuary communities improve communication and the ability to coordinate land and water use decisions to ensure the future good health of the estuary’s resources.

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Landscape Evolution Of The Dry Valleys, Transantarctic Mountains: Tectonic Implications, David E. Sugden, George H. Denton, David R. Marchant Jun 1995

Landscape Evolution Of The Dry Valleys, Transantarctic Mountains: Tectonic Implications, David E. Sugden, George H. Denton, David R. Marchant

Earth Science Faculty Scholarship

There are different views about the amount and timing of surface uplift in the Transantarctic Mountains and the geophysical mechanisms involved. Our new interpretation of the landscape evolution and tectonic history of the Dry Valleys area of the Transantarctic Mountains is based on geomorphic mapping of an area of 10,000 km(2). The landforms are dated mainly by their association with volcanic ashes and glaciomarine deposits and this permits a reconstruction of the stages and timing of landscape evolution. Following a lowering of base level about 55 m.y. ago, there was a phase of rapid denudation associated with planation and escarpment …

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Global Perspective Of Nitrate Flux In Ice Cores, Qinzhao Yang, Paul Andrew Mayewski, Sallie Whitlow, Michael Morrison, Robert Talbot, Jack Dibb, Ernst Linder Mar 1995

Global Perspective Of Nitrate Flux In Ice Cores, Qinzhao Yang, Paul Andrew Mayewski, Sallie Whitlow, Michael Morrison, Robert Talbot, Jack Dibb, Ernst Linder

Earth Science Faculty Scholarship

The relationships between the concentration and the flux of chemical species(Cl-, NO3-, SO42-, Na+, K+, NH4+, Mg2+, Ca2+) versus snow accumulation rate were examined at GISP2 and 20D in Greenland, Mount Logan from the St. Elias Range, Yukon Territory, Canada, and Sentik Glacier from the northwest end of the Zanskar Range in the Indian Himalayas. At all sites, only nitrate flux is significantly(α = 0.05) related to snow accumulation rate. Of all the chemical series, only nitrate concentration data are normally …

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A Wavelet Analysis Of Pliopleistocene Climate Indicators: A New View Of Periodicity Evolution, Edward W. Bolton, Kirk A. Maasch, Jonathan M. Lilly Jan 1995

A Wavelet Analysis Of Pliopleistocene Climate Indicators: A New View Of Periodicity Evolution, Edward W. Bolton, Kirk A. Maasch, Jonathan M. Lilly

Earth Science Faculty Scholarship

Wavelet analysis offers an alternative to Fourier based time-series analysis, and is particularly useful when the amplitudes and periods of dominant cycles are time dependent. We analyse climatic records derived from oxygen isotopic ratios of marine sediment cores with modified Morlet wavelets. We use a normalization of the Morlet wavelets which allows direct correspondence with Fourier analysis. This provides a direct view of the oscillations at various frequencies, and illustrates the nature of the time-dependence of the dominant cycles.

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Derived Bedrock Elevations, Strain Rates And Stresses From Measured Surface Elevations And Velocities - Jakobshavns-Isbrae, Greenland, J. L. Fastook, H. H. Brecher, Terence J. Hughes Jan 1995

Derived Bedrock Elevations, Strain Rates And Stresses From Measured Surface Elevations And Velocities - Jakobshavns-Isbrae, Greenland, J. L. Fastook, H. H. Brecher, Terence J. Hughes

Earth Science Faculty Scholarship

Jakobshavns Isbrae (69 degrees 10'N, 49 degrees 5'W) drains about 6.5% of the Greenland ice sheet and is the fastest ice stream known. The Jakobshavns Isbrae basin of about 10 000 km(2) was mapped photogrammetrically from four sets of aerial photography, two taken in July 1985 and two in July 1986. Positions and elevations of several hundred natural features on the ice surface were determined for each epoch by photogrammetric block-aerial triangulation, and surface velocity vectors were computed from the positions. The two flights in 1985 yielded the best results and provided most common points (716) for velocity determinations and …

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Paleoglaciologys Grand Unsolved Problem, Mikhail G. Grosswald, Terence J. Hughes Jan 1995

Paleoglaciologys Grand Unsolved Problem, Mikhail G. Grosswald, Terence J. Hughes

Earth Science Faculty Scholarship

The paleoglaciological concept that during the Pleistocene glacial hemi-cycles a super-large, structurally complex ice sheet developed in the Arctic and behaved as a single dynamic system, as the Antarctic ice sheet does today, has not yet been subjected to concerted studies designed to test the predictions of this concept. Yet, it may hold the keys to solutions of major problems of paleoglaciology, to understanding climate and sea-level changes. The Russian Arctic is the least-known region exposed to paleoglaciation by a hypothetical Arctic ice sheet but now it is more open to testing the concept. Implementation of these tests is a …

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Changes In Continental And Sea-Salt Atmospheric Loadings In Central Greenland During The Most Recent Deglaciation: Model-Based Estimates, R. B. Alley, R. C. Finkel, K. Nishizumi, A. Anandakrishnan, C. A. Shuman, G. Mershon, G. A. Zielinski, Paul Andrew Mayewski Jan 1995

Changes In Continental And Sea-Salt Atmospheric Loadings In Central Greenland During The Most Recent Deglaciation: Model-Based Estimates, R. B. Alley, R. C. Finkel, K. Nishizumi, A. Anandakrishnan, C. A. Shuman, G. Mershon, G. A. Zielinski, Paul Andrew Mayewski

Earth Science Faculty Scholarship

By fitting a very simple atmospheric impurity model to high-resolution data on ice accumulation and contaminant f1uxes in the GISP2 ice core, we have estimated changes in the atmospheric concentrations of soluble major ions, insoluble particulates and 10Be during the transition from glacial to Holocene conditions. For many species, changes in concentration in the ice typically overestimate atmospheric changes, and changes in flux to the ice typically underestimate atmospheric changes, because times of increased atmospheric contaminant loading are also times of reduced snowfall. The model interpolates between the flux and concentration records by explicitly allowing [or wet- and dry- …

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Bioarchaeological And Climatological Evidence For The Fate Of Norse Farmers In Medieval Greenland, P. C. Buckland, T. Amorosi, L. K. Barlow, A. J. Dugmore, Paul Andrew Mayewski, T. H. Mcgovern, A. E. J. Ogilvie, J. P. Sadler, P. Skidmore Jan 1995

Bioarchaeological And Climatological Evidence For The Fate Of Norse Farmers In Medieval Greenland, P. C. Buckland, T. Amorosi, L. K. Barlow, A. J. Dugmore, Paul Andrew Mayewski, T. H. Mcgovern, A. E. J. Ogilvie, J. P. Sadler, P. Skidmore

Earth Science Faculty Scholarship

Greenland, far north land of the Atlantic, has often been beyond the limit of European farming settlement. One of its Norse settlements, colonized just before AD 1000, is — astonishingly — not even at the southern tip, but a way up the west coast, the 'Western Settlement'. Environmental studies show why its occupation came to an end within five centuries, leaving Greenland once more a place of Arctic-adapted hunters.

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The Divided Information Superhighway, Robert Kuttner Jan 1995

The Divided Information Superhighway, Robert Kuttner

Maine Policy Review

This issue marks the introduction of the Margaret Chase Smith Essay, which will be a feature in each issue honoring Sen. Smith by focusing on issues related to citizenship, ethics in government, and integrity as a virtue of public leadership. In this first essay, economist Robert Kuttner asks some important ethical questions about the new world of electronic communications. He suggests that who plays and who pays are very important issues that have not been adequately considered in the highly technical and competitive world that will mark the 21st century. [This essay originally appeared as a column in the …

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Electric Market Restructuring: Environmental Considerations, Armond Cohen Jan 1995

Electric Market Restructuring: Environmental Considerations, Armond Cohen

Maine Policy Review

In the past few years,Maine's electric utilities have begun to face the forces of competition.Maineis experiencing the effects of a national trend, a shift from a traditional and regulated system to a more innovative and competitive one. Armond Cohen explores the environmental impacts that are at stake in restructuring and offers some possible solutions. This article is taken from the author’s presentation at a December 1994 conference entitled ”Retail Wheeling,” sponsored by the Margaret Chase Smith Center for Public Policy's Project for the Study of Regulation and the Environment.

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Evolution Of Maine’S Electric Utility Industry, 1975-1995, Carroll R. Lee, Richard C. Hill Jan 1995

Evolution Of Maine’S Electric Utility Industry, 1975-1995, Carroll R. Lee, Richard C. Hill

Maine Policy Review

Recent articles in Maine Policy Review have focused on the sweeping changes taking place in Maine’s electric industry. We continue the dialogue with this article by Carroll Lee, Vice President-Operations at Bangor Hydro-Electric Company and Richard Hill, retired University of Maine Professor. Lee and Hill trace the electric industry evolution back 20 years and offer a comprehensive and integrated perspective on how this industry has progressed from a monopoly to one with significant elements of competition.

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Why Conservation Matters And What We Can Do About It, John C. Sawhill Jan 1995

Why Conservation Matters And What We Can Do About It, John C. Sawhill

Maine Policy Review

While environmental and economic needs have long been considered to be in direct opposition to one another, a new approach to environmental conservation is emerging. Called the "ecosystem" approach, it focuses not only on protecting the environment and its species, but also seeks new ways of balancing these interests with human needs. The article is drawn from a speech delivered by John C. Sawhill at the Summer Lecture Series of the College of the Atlantic,Bar Harbor,Maine, on August 2, 1994. Sawhill outlines the conservation principles that guide The Nature Conservancy and provides examples of how the ecosystem approach has led …

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The Complexities Of Decision-Making Related To Health Risk Assessments, Barbara A. Knuth Jan 1995

The Complexities Of Decision-Making Related To Health Risk Assessments, Barbara A. Knuth

Maine Policy Review

Maine, like the nation, has focused a great deal of recent attention on determining acceptable levels of environmental and human health risk. Barbara discusses the role and uses of scientific information in risk assessment and public policy debate. Similar to Kevin Boyle's previous article (featured in the December 1994 issue of Maine Policy Review), Knuth discusses the 1992 Maine Board of Environmental Protection hearings which focused on the human consumption of fish potentially contaminated with dioxin.

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