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Jaromy R. Green

Publications and source records attributed to Jaromy R. Green.

5 recordsLinked to original sources
USGS2005

Development of a local meteoric water line for southeastern Idaho, western Wyoming, and south-central Montana

Linear-regression analysis was applied to stable hydrogen (H) and oxygen (O) isotope data in 72 snow-core and precipitation samples collected during 1999-2001 to determine the Local Meteoric Water Line (LMWL) for southeastern Idaho, western Wyoming, and south-central Montana. On the basis of (1) residuals from the regression model, (2) comparison of study-area deuterium-excess (d-excess) values with the global range of d-excess values, and (3) outlier analysis by means of Chauvenet's Criterion, values of four samples were excluded from final regression analysis of the dataset. Regression results for the 68 remaining samples yielded a LMWL defined by the equation ?H = 7.95 18O + 8.09 (r? = 0.98). This equation will be useful as a reference point for future studies in this area that use stable isotopes of H and O to determine sources of ground-water recharge, to determine water-mineral exchange, to evaluate surface-water and groundwater interaction, and to analyze many other geochemical and hydrologic problems.

Scientific Investigations Report↗
USGS2003

Reevaluation of background iodine-129 concentrations in water from the Snake River Plain aquifer, Idaho, 2003

Background concentrations of iodine-129 (129I, half-life = 15.7 million years) resulting from natural production in the earth?s atmosphere, in situ production in the earth by spontaneous fission of uranium-238(238U), and fallout from nuclear weapons tests conducted in the 1950s and 1960s were reevaluated on the basis of 52 analyses of ground- and surface-water samples collected from the eastern Snake River Plain in southeastern Idaho. The background concentration estimated using the results of a subset of 30 ground-water samples analyzed in this reevaluation is 5.4 attocuries per liter (aCi/L; 1 aCi = 10-18 curies) and the 95-percent nonparametric confidence interval is 5.2 to 10.0 aCi/L. In a previous study, a background 129I concentration was estimated on the basis of analyses of water samples from 16 sites on or tributary to the eastern Snake River Plain. At the 99-percent confidence level, background concentrations of 129I in that study were less than or equal to 8.2 aCi/L. During 1993?94, 34 water samples from 32 additional sites were analyzed for 129I to better establish the background concentrations in surface and ground water from the eastern Snake River Plain that is presumed to be unaffected by wastedisposal practices at the Idaho National Engineering and Environmental Laboratory (INEEL). Surface water contained larger 129I concentrations than water from springs and wells contained. Because surface water is more likely to be affected by anthropogenic fallout and evapotranspiration, background 129I concentrations were estimated in the current research using the laboratory results of ground-water samples that were assumed to be unaffected by INEEL disposal practices.

Idaho↗
USGS2002

Atmospheric mercury deposition during the last 270 years: A glacial ice core record of natural and anthropogenic sources

Mercury (Hg) contamination of aquatic ecosystems and subsequent methylmercury bioaccumulation are significant environmental problems of global extent. At regional to global scales, the primary mechanism of Hg contamination is atmospheric Hg transport. Thus, a better understanding of the long-term history of atmospheric Hg cycling and quantification of the sources is critical for assessing the regional and global impact of anthropogenic Hg emissions. Ice cores collected from the Upper Fremont Glacier (UFG), Wyoming, contain a high-resolution record of total atmospheric Hg deposition (ca. 1720−1993). Total Hg in 97 ice-core samples was determined with trace-metal clean handling methods and low-level analytical procedures to reconstruct the first and most comprehensive atmospheric Hg deposition record of its kind yet available from North America. The record indicates major atmospheric releases of both natural and anthropogenic Hg from regional and global sources. Integrated over the past 270-year ice-core history, anthropogenic inputs contributed 52%, volcanic events 6%, and background sources 42%. More significantly, during the last 100 years, anthropogenic sources contributed 70% of the total Hg input. Unlike the 2−7-fold increase observed from preindustrial times (before 1840) to the mid-1980s in sediment-core records, the UFG record indicates a 20-fold increase for the same period. The sediment-core records, however, are in agreement with the last 10 years of this ice-core record, indicating declines in atmospheric Hg deposition.

Environmental Science & Technology↗
USGS2000

Global ice-core research: Understanding and applying environmental records of the past

One way to study Earth’s past environmental conditions is to look at ice cores recovered from glaciers. Every year a layer of snow accumulates on glaciers, like a page in a history book, and eventually turns to ice. Like reading the pages of a history book, analyzing the layers in a glacial ice core for specific chemical and physical components is a way of “reading” the environmental changes of the past. Information from ice cores collected from Greenland and Antarctica already has provided important historical clues toward a better understanding of modern global environmental changes (Dansgaard and Oeschger, 1989; Lorius and others, 1989). Environmental changes are of major concern at low- or mid-latitude regions of our Earth simply because this is where 80 to 90 percent of the world’s human population live. Ice cores collected from isolated polar regions are, at best, proxy indicators of low- and mid-latitude environmental changes. Because polar icecore research is limiting in this sense, ice cores from low- and mid-latitude glaciers are being used to study past environmental changes in order to better understand and predict future environmental changes that may affect the populated regions of the world.

Idaho;Wyoming↗