Skip to main content
U.S. flag

An official website of the United States government

Conference Papers

Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.

Filter Total Items: 5500

Net carbon exchange across the Arctic tundra-boreal forest transition in Alaska 1981-2000 Net carbon exchange across the Arctic tundra-boreal forest transition in Alaska 1981-2000

Shifts in the carbon balance of high-latitude ecosystems could result from differential responses of vegetation and soil processes to changing moisture and temperature regimes and to a lengthening of the growing season. Although shrub expansion and northward movement of treeline should increase carbon inputs, the effects of these vegetation changes on net carbon exchange have not been...
Authors
Catharine Copass Thompson, A. D. McGuire, Joy S. Clein, F. S. Chapin, J. Beringer

New ghost-node method for linking different models with varied grid refinement New ghost-node method for linking different models with varied grid refinement

A flexible, robust method for linking grids of locally refined ground-water flow models constructed with different numerical methods is needed to address a variety of hydrologic problems. This work outlines and tests a new ghost-node model-linking method for a refined "child" model that is contained within a larger and coarser "parent" model that is based on the iterative method of...
Authors
S.C. James, J.E. Dickinson, S.W. Mehl, M. C. Hill, S. A. Leake, G.A. Zyvoloski, A.-A. Eddebbarh

Numerical modeling of magnetic moments for UXO applications Numerical modeling of magnetic moments for UXO applications

The surface magnetic anomaly observed in UXO clearance is mainly dipolar and, consequently, the dipole is the only magnetic moment regularly recovered in UXO applications. The dipole moment contains information about intensity of magnetization but lacks information about shape. In contrast, higher-order moments, such as quadrupole and octupole, encode asymmetry properties of the...
Authors
V. Sanchez, Y. Li, M. Nabighian, D. Wright

Oil resources - Estimates and uncertainties Oil resources - Estimates and uncertainties

Oil reserves are reasonably well known, but they are not a reliable indicator of longterm supply. Future oil availability will depend upon reserve additions, which are highly uncertain. New reserves will come from three sources: 1) new field discoveries, 2) growth of reserves in existing fields, and 3) development of unconventional resources. U.S. Geological Survey estimates of global...
Authors
D. L. Gautier

Organic geochemistry - A retrospective of its first 70 years Organic geochemistry - A retrospective of its first 70 years

Organic geochemistry had its origin in the early part of the 20th century when organic chemists and geologists realized that detailed information on the organic materials in sediments and rocks was scientifically interesting and of practical importance. The generally acknowledged "father" of organic geochemistry is Alfred E. Treibs (1899-1983), who discovered and described, in 1936...
Authors
K.A. Kvenvolden

Overview of selected surrogate technologies for continuous suspended-sediment monitoring Overview of selected surrogate technologies for continuous suspended-sediment monitoring

Surrogate technologies for inferring selected characteristics of suspended sediments in surface waters are being tested by the U.S. Geological Survey and several partners with the ultimate goal of augmenting or replacing traditional monitoring methods. Optical properties of water such as turbidity and optical backscatter are the most commonly used surrogates for suspended-sediment...
Authors
J. R. Gray, J. W. Gartner

Panel: Eco-informatics and decision making managing our natural resources Panel: Eco-informatics and decision making managing our natural resources

This panel responds to the December 2004 workshop on Eco-Informatics and Decision Making [1], which addressed how informatics tools can help with better management of natural resources and policy making. The workshop was jointly sponsored by the NSF, NBII, NASA, and EPA. Workshop participants recommended that informatics research in four IT areas be funded: modeling and simulation, data...
Authors
J.B. Gushing, T. Wilson, F. Martin, J. Schnase, S. Spengler, L. Sugarbaker, T. Pardo

Polar bear research in Alaska Polar bear research in Alaska

Since the 13th Working Meeting of the Polar Bear Specialist Group the U.S. Geological Survey (USGS) has seen the completion of many research projects and the start of many new ones. Much has been accomplished and yet we have new challenges awaiting us. This report summarises our focal questions and progress in those areas.
Authors
George M. Durner, Steven C. Amstrup, Geoff S. York, Eric V. Regehr, Kristin S. Simac, Tom S. Smith, Steven T. Partridge, Torsten Bentzen, Kristin S. Amstrup, David C. Douglas

Postrelease movements and survival of adult and young black-footed ferrets Postrelease movements and survival of adult and young black-footed ferrets

A successful captive breeding program for highly endangered black-footed ferrets (Mustela nigripes) has resulted in surplus animals that have been released at multiple sites since 1991. Because reproductive output of captive ferrets declines after several years, many adult ferrets must be removed from captive breeding facilities annually to keep total production high. Adults are...
Authors
Dean E. Biggins, Jerry L. Godbey, Travis M. Livieri, Marc R. Matchett, Brent D. Bibles

Prediction and discovery of new geothermal resources in the Great Basin: Multiple evidence of a large undiscovered resource base Prediction and discovery of new geothermal resources in the Great Basin: Multiple evidence of a large undiscovered resource base

Geothermal potential maps by themselves cannot directly be used to estimate undiscovered resources. To address the undiscovered resource base in the Great Basin, a new and relatively quantitative methodology is presented. The methodology involves three steps, the first being the construction of a data-driven probabilistic model of the location of known geothermal systems using weights of...
Authors
M.F. Coolbaugh, G. L. Raines, R. E. Zehner, L. Shevenell, C.F. Williams
Was this page helpful?