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Full-Text Articles in Earth Sciences
The 19th Annual International Conference On Soils, Sediments And Water
The 19th Annual International Conference On Soils, Sediments And Water
Annual Conference on Soils, Sediments and Water: Abstracts
Conference at a Glance Monday, October 20, 2003 Workshops Workshops #1-2: 10:00am – 5:00pm Workshops # 3-4: 1:00 – 5:00pm Workshop # 5: 1:00 – 3:00pm Workshop # 6: 3:00 – 5:00pm Workshop # 1: Theory and Use of Field Portable X-ray Fluorescence for Soil Analysis Workshop # 2: In-Situ Chemical Oxidation Workshop Workshop # 3: TBA/MTBE Remediation Seminar Workshops # 4: A Practical Approach for Assessing Upward Vapor Instrusion Risk Workshop # 5: The Arsenic Nobody Wanted: Now What? A Panel Discussion on Arsenic in Communities Workshop # 6: Implementing the Massachusetts DEP's New Data Enhancement Policy - PRACTICAL …
Review Of Irwin M. Brodo, Sylvia Duran Sharnoff, Stephen Sharnoff: Lichens Of North America, Lynn Margulis
Review Of Irwin M. Brodo, Sylvia Duran Sharnoff, Stephen Sharnoff: Lichens Of North America, Lynn Margulis
Lynn Margulis (1938 - 2011)
No abstract provided.
Optimal Surface Temperature Reconstructions Using Terrestrial Borehole Data, M. E. Mann, S. Rutherford, Raymond S. Bradley, M. K. Hughes, F. T. Keimig
Optimal Surface Temperature Reconstructions Using Terrestrial Borehole Data, M. E. Mann, S. Rutherford, Raymond S. Bradley, M. K. Hughes, F. T. Keimig
Raymond S Bradley
We derive an optimal Northern Hemisphere mean surface temperature reconstruction from terrestrial borehole temperature profiles spanning the past five centuries. The pattern of borehole ground surface temperature (GST) reconstructions displays prominent discrepancies with instrumental surface air temperature (SAT) estimates during the 20th century, suggesting the presence of a considerable amount of noise and/or bias in any underlying spatial SAT signal. The vast majority of variance in the borehole dataset is efficiently retained by its two leading eigenvectors. A sizable share of the variance in the first eigenvector appears to be associated with non-SAT related bias in the borehole data. A …
Watershed-Scale Effects Of Urbanization On Sediment Export: Assessment And Policy, Timothy O. Randhir
Watershed-Scale Effects Of Urbanization On Sediment Export: Assessment And Policy, Timothy O. Randhir
Timothy O. Randhir
Built components of watersheds are associated with impervious surfaces that alter hydrology, disrupt ecosystems, and affect water quality. This study focuses on the impervious factor as a tool for assessment and policy design to address water quality impacts. The empirical model uses a combination of watershed simulation and statistical regression modeling to study sediment loading at various stages of urbanization. The policy design is based on private behavior in a watershed setting to develop appropriate economic approaches. The incentives through taxes, subsidies, and cost sharing are based on water quality impacts. It was observed that nonlinearity in response functions resulted …
Variability Of Snow Accumulation And Isotopic Composition On Nevado Sajama, Bolivia, D. R. Hardy, M. Vuille, Raymond S. Bradley
Variability Of Snow Accumulation And Isotopic Composition On Nevado Sajama, Bolivia, D. R. Hardy, M. Vuille, Raymond S. Bradley
Raymond S Bradley
High-elevation ice caps develop an archive of atmospheric constituents and properties through the accumulation of snowfall. The timing of precipitation events, therefore, fundamentally governs the environmental information that ice core records can provide. These events are often highly seasonal, as are various postdepositional processes influencing the snow's physical and chemical properties. Knowledge of climatic conditions at an ice core site is essential to a full understanding of the ice core record. This work reports on 4 years of meteorological measurements near the summit of Nevado Sajama, an ice-capped peak rising ∼2500 m above the South American Altiplano (elevation 6542 m), …
Rapid Lacustrine Response To Recent High Arctic Warming: A Diatom Record From Sawtooth Lake, Ellesmere Island, Nunavut, Bianca B. Perren, Raymond S. Bradley, Pierre Francus
Rapid Lacustrine Response To Recent High Arctic Warming: A Diatom Record From Sawtooth Lake, Ellesmere Island, Nunavut, Bianca B. Perren, Raymond S. Bradley, Pierre Francus
Raymond S Bradley
Diatoms from Sawtooth Lake (79 20'N, 81 51'W) on the Fosheim Peninsula in Central Ellesmere Island, Canada were analyzed to assess the temporal extent and magnitude of climatic change in the High Arctic during the late Holocene. Diatom results from the sediment cores show an absence of diatoms throughout the last ;2.5 ka (4.6 m) until the 1920s. However, ca. 1926 (5.3-cm depth), a rapid colonization of diatoms in the lake occurred. Within the uppermost section of the core (;1920 to ;1997), the diatom flora shift from a small Fragilaria-dominated assemblage to a more diverse assemblage that is dominated by …
Reply To Comment By N. D. Marsh And H. Svensmark On “Solar Influences On Cosmic Rays And Cloud Formation: A Reassessment”, B. Sun, Raymond S. Bradley
Reply To Comment By N. D. Marsh And H. Svensmark On “Solar Influences On Cosmic Rays And Cloud Formation: A Reassessment”, B. Sun, Raymond S. Bradley
Raymond S Bradley
No abstract provided.
Modeling Δ18o In Precipitation Over The Tropical Americas: 1. Interannual Variability And Climatic Controls, M. Vuille, Raymond S. Bradley, M. Werner, R. Healy, F. Keimig
Modeling Δ18o In Precipitation Over The Tropical Americas: 1. Interannual Variability And Climatic Controls, M. Vuille, Raymond S. Bradley, M. Werner, R. Healy, F. Keimig
Raymond S Bradley
We use two atmospheric general circulation models (AGCMs), the ECHAM-4 and the GISS II models, to analyze the interannual variability of δ18O in precipitation over the tropical Americas. Several different simulations with isotopic tracers forced with observed global sea surface temperatures (SST) between 1950 and 1998 reveal the influence of varying temperature, precipitation amount, and moisture source contributions on the predicted δ18O distribution. Observational evidence from climatic (NCEP-NCAR) and sparse stable isotope (IAEA-GNIP) data is used to evaluate model performance. The models capture the essential features of surface climate over the tropical Americas in terms of both their spatial and …
Modeling Δ18o In Precipitation Over The Tropical Americas: 2. Simulation Of The Stable Isotope Signal In Andean Ice Cores, M. Vuille, Raymond S. Bradley, R. Healy, M. Werner, D. R. Hardy, L. G. Thompson, F. Keimig
Modeling Δ18o In Precipitation Over The Tropical Americas: 2. Simulation Of The Stable Isotope Signal In Andean Ice Cores, M. Vuille, Raymond S. Bradley, R. Healy, M. Werner, D. R. Hardy, L. G. Thompson, F. Keimig
Raymond S Bradley
We use the ECHAM-4 and the GISS II atmospheric general circulation models (AGCM) with incorporated stable isotopic tracers and forced with observed global sea surface temperatures (SST) between 1979 and 1998, to simulate the δ18O signal in three tropical Andean ice cores, from Huascarán (Peru), Quelccaya (Peru), and Sajama (Bolivia). In both models, the simulated stable isotopic records compare favorably with the observational data, when the seasonality of precipitation and dry season loss due to sublimation and wind scour are taken into account. Our simulations indicate a significant influence of the local climatic conditions (temperature and precipitation amount) on the …