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Articles 301 - 330 of 965
Full-Text Articles in Earth Sciences
Investigations Into The Regional And Local Timescale Variations Of Subglacial Drainage Networks, Justin Hiester
Investigations Into The Regional And Local Timescale Variations Of Subglacial Drainage Networks, Justin Hiester
Dissertations and Theses
Subglacial water plays an important role in the regulation of an ice sheet's mass balance. It may be the dominant control on the velocities of ice streams and outlet glaciers on scales of months to millennia. Recent satellite observations of ice surface elevation changes have given researchers new insights into how subglacial water is stored and transported. Localized uplift and settling of the ice surface implies that lakes exist beneath the ice sheet that are being filled and drained on relatively short time scales. %At the base of an ice sheet water can be transported through a variety of drainage …
Oil-Source Rock Correlation In The Late Paleozoic, Denver Basin, Nebraska: The Search For A Negative Δ¹³C Anomaly In Pennsylvanian–Permian Cyclothems, John P. Still
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
Late Paleozoic sedimentation in the Denver basin occurred in two environmentally distinct depocenters. The northern-most Alliance Basin has been interpreted to have a restricted character: anhydrite-bearing mudstones are present in cyclothems comprising wackestone, packstone and mudstone. The source of petroleum produced from these intervals is considered to be organic-rich units within these cyclothems. Oil recovered from late Paleozoic reservoirs has δ13C values that range from -30.8‰ to -28.8‰: values that are lower than those reported previously for prospective source rocks from this interval. Cores from seven wells that penetrate upper Pennsylvanian to lower Permian rocks have been chosen for analysis. …
Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman
Lower San Luis Obispo Creek Stewardship Plan, Raven Lukehart, Daniel Bohlman
Natural Resources Management and Environmental Sciences
No abstract provided.
Transforming The Teaching Of Geoscience And Sustainability, David Gosselin, Cathy Manduca, Timothy J. Bralower, David Mogk
Transforming The Teaching Of Geoscience And Sustainability, David Gosselin, Cathy Manduca, Timothy J. Bralower, David Mogk
School of Natural Resources: Faculty Publications
The geosciences have an important role to play in addressing whether humans can live sustainably on Earth. From water to energy, from climate change to natural hazards, geoscience is central to solving a wide range of problems.
Two projects funded by the National Science Foundation (NSF) support faculty in incorporating aspects of sustainability in their teaching: the Interdisciplinary Teaching of Geoscience for a Sustainable Future ( InTeGrate) Center in the Geosciences and the On the Cutting Edge Faculty Development Program in the Geosciences. The former is funded by NSF’s Science Technology, Engineering, and Mathematics (STEM) Faculty Development Program, and the …
Morphodynamic Signatures Of Braiding Mechanisms As Expressed Through Change In Sediment Storage In A Gravel-Bed River, Joseph Michael Wheaton, James Brasington, Stephen Darby, Alan Kasprak, David Sear, Damiá Vericat
Morphodynamic Signatures Of Braiding Mechanisms As Expressed Through Change In Sediment Storage In A Gravel-Bed River, Joseph Michael Wheaton, James Brasington, Stephen Darby, Alan Kasprak, David Sear, Damiá Vericat
Watershed Sciences Faculty Publications
[1] Previous flume-based research on braided channels has revealed four classic mechanisms that produce braiding: central bar development, chute cutoff, lobe dissection, and transverse bar conversion. The importance of these braiding mechanisms relative to other morphodynamic mechanisms in shaping braided rivers has not yet been investigated in the field. Here we exploit repeat topographic surveys of the braided River Feshie (UK) to explore the morphodynamic signatures of different mechanisms of change in sediment storage. Our results indicate that, when combined, the four classic braiding mechanisms do indeed account for the majority of volumetric change in storage in the study reach …
Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend
Late-Quaternary Channel Migration In Red Rock Canyon State Park, California; Implications For Regional Tectonics, Kirk Forrest Townsend
Natural Resources Management and Environmental Sciences
The Iron Canyon Valley, located at the southern end of the eastern Sierra Nevada at the boundary between the Mojave and Basin and Range tectonic provinces, exhibits clear evidence, over graded timescales, of development through monoclinal shifting, which is the tendency of streams flowing parallel to strike over sedimentary rocks to shift down-dip. Although the character of the valley and bedrock dip indicates development through monoclinal shifting, the current stream network is located up-dip on the east side of the valley. Mapping the surficial geology of the valley revealed the presence of dissected alluvial surfaces approximately 85 meters above modern …
Toward Global Drought Early Warning Capability: Expanding International Cooperation For The Development Of A Framework For Monitoring And Forecasting, Will Pozzi, Justin Sheffield, Robert Stefanski, Douglas Cripe, Roger Pulwarty, Jürgen V. Vogt, Richard R. Heim Jr., Michael J. Brewer, Mark Svoboda, Rogier Westerhoff, Albert I. J. M. Van Dijk, Benjamin Lloyd-Hughes, Florian Pappenberger, Micha Werner, Emanuel Dutra, Fredrik Wetterhall, Wolfgang Wagner, Siegfried Schubert, Kingtse Mo, Margaret Nicholson, Lynette Bettio, Liliana Nunez, Rens Van Beek, Marc Bierkens, Luis Gustavo Goncalves De Goncalves, João Gerd Zell De Mattos, Richard Lawford
Toward Global Drought Early Warning Capability: Expanding International Cooperation For The Development Of A Framework For Monitoring And Forecasting, Will Pozzi, Justin Sheffield, Robert Stefanski, Douglas Cripe, Roger Pulwarty, Jürgen V. Vogt, Richard R. Heim Jr., Michael J. Brewer, Mark Svoboda, Rogier Westerhoff, Albert I. J. M. Van Dijk, Benjamin Lloyd-Hughes, Florian Pappenberger, Micha Werner, Emanuel Dutra, Fredrik Wetterhall, Wolfgang Wagner, Siegfried Schubert, Kingtse Mo, Margaret Nicholson, Lynette Bettio, Liliana Nunez, Rens Van Beek, Marc Bierkens, Luis Gustavo Goncalves De Goncalves, João Gerd Zell De Mattos, Richard Lawford
National Drought Mitigation Center: Faculty Publications
The need for a global drought early warning framework. Drought has had a significant impact on civilization throughout history in terms of reductions in agricultural productivity, potable water supply, and economic activity, and in extreme cases this has led to famine. Every continent has semiarid areas, which are especially vulnerable to drought. The Intergovernmental Panel on Climate Change has noted that average annual river runoff and water availability are projected to decrease by 10%–13% over some dry and semiarid regions in mid and low latitudes, increasing the frequency, intensity, and duration of drought, along with its associated impacts. The sheer …
Molecular Detection Of Campylobacter Spp. And Fecal Indicator Bacteria During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Jingrang Lu, Hodon Ryu, Jason R. Vogel, Jorge Santo Domingo, Nicholas J. Ashbolt
Molecular Detection Of Campylobacter Spp. And Fecal Indicator Bacteria During The Northern Migration Of Sandhill Cranes (Grus Canadensis) At The Central Platte River, Jingrang Lu, Hodon Ryu, Jason R. Vogel, Jorge Santo Domingo, Nicholas J. Ashbolt
United States Environmental Protection Agency: Publications
The risk to human health of the annual sandhill crane (Grus canadensis) migration through Nebraska, which is thought to be a major source of fecal pollution of the central Platte River, is unknown. To better understand potential risks, the presence of Campylobacter species and three fecal indicator bacterial groups (Enterococcus spp., Escherichia coli, and Bacteroidetes) was assayed by PCR from crane excreta and water samples collected during their stopover at the Platte River, Nebraska, in 2010. Genus-specific PCR assays and sequence analyses identified Campylobacter jejuni as the predominant Campylobacter species in sandhill crane excreta. Campylobacter …
The Missing Piece: Drought Impacts Monitoring Report From A Workshop In Tucson, Az March 5-6, 2013, Kirsten Lackstrom, Amanda Brennan, Daniel Ferguson, Mike Crimmins, Lisa Darby, Kirstin Dow, Keith Ingram, Alison Meadow, Henry Reges, Mark Shafer, Kelly Helm Smith
The Missing Piece: Drought Impacts Monitoring Report From A Workshop In Tucson, Az March 5-6, 2013, Kirsten Lackstrom, Amanda Brennan, Daniel Ferguson, Mike Crimmins, Lisa Darby, Kirstin Dow, Keith Ingram, Alison Meadow, Henry Reges, Mark Shafer, Kelly Helm Smith
National Drought Mitigation Center: Faculty Publications
Based on a shared interest to better understand the impacts of drought and the potential utility of using drought impacts reporting as a tool for monitoring conditions, researchers from the Carolinas RISA (Dow, Lackstrom, and Brennan), the Climate Assessment for the Southwest (Crimmins and Ferguson), and the Southwest Climate Science Center (Meadow) decided to convene a workshop in Tucson in March 2013. The primary goal was to assemble a small group of university and agency scientists involved with drought impacts monitoring to discuss opportunities and barriers associated with drought impacts reporting, recommend best practices for implementing a drought impacts reporting …
Guidance Statement On Undertaking Seismic Surveys In Western Australian Waters, Department Of Fisheries
Guidance Statement On Undertaking Seismic Surveys In Western Australian Waters, Department Of Fisheries
Fisheries Occasional Publications
No abstract provided.
The Geology Of The South Antelope Pass Area Of The Southern Peloncillo Mountains, Hidalgo County, New Mexico, John A. Yellich
The Geology Of The South Antelope Pass Area Of The Southern Peloncillo Mountains, Hidalgo County, New Mexico, John A. Yellich
Masters Theses
Volcanic activity during the middle and late Tertiary has been recorded in the mountain ranges of the southwestern United States and northern Mexico and the two provinces of prominent volcanic activity, the Sierra Madre Occidental and the Mogollon Plateau, dominantly rhyolitic in composition, are connected by the Peloncillo Range. The predominant rock chemistry of the south Antelope Pass area is “rhyolitic”; however, lava rock types dominate over welded tuff rock types of the two provinces. There is a limited pre-Tertiary rock record of limestones and sandstones in the northeastern part of the study area. The rest of the study area …
Evidence For Reactive Reduced Phosphorus Species In The Early Archean Ocean, Matthew A. Pasek, Jelte P. Hammeijer, Roger Buick, Maheen Gull, Zachary D. Atlas
Evidence For Reactive Reduced Phosphorus Species In The Early Archean Ocean, Matthew A. Pasek, Jelte P. Hammeijer, Roger Buick, Maheen Gull, Zachary D. Atlas
School of Geosciences Faculty and Staff Publications
It has been hypothesized that before the emergence of modern DNA–RNA–protein life, biology evolved from an “RNA world.” However, synthesizing RNA and other organophosphates under plausible early Earth conditions has proved difficult, with the incorporation of phosphorus (P) causing a particular problem because phosphate, where most environmental P resides, is relatively insoluble and unreactive. Recently, it has been proposed that during the Hadean–Archean heavy bombardment by extraterrestrial impactors, meteorites would have provided reactive P in the form of the iron–nickel phosphide mineral schreibersite. This reacts in water, releasing soluble and reactive reduced P species, such as phosphite, that could then …
Decomposition And Nutrient Release Of Different Cover Crops In Organic Farm Systems, Jianru Shi
Decomposition And Nutrient Release Of Different Cover Crops In Organic Farm Systems, Jianru Shi
School of Natural Resources: Dissertations, Theses, and Student Research
Cover crops act as green manure adding organic matter to agricultural-soils. For legume green manures to be an effective nitrogen (N) source for organic farming systems, their N release must be in synchrony with crop N demand. The objectives of this study were 1) determine the decomposition rates of three common cover crops (white clover, (Trifolium repens,L ) red clover (Trifolium pratense L.) and soybean (Glycine max L) in order to determine when most N was released and its synchrony with subsequent corn crop uptake; 2) we focused on the effect of cover crops on soil …
Were All Devonian Seeds Cupulate? A Reinvestigation Of Pseudosporogonites Hallei, Xenotheca Bertrandii, And Aglosperma Spp., Cyrille Prestianni, Jason Hilton, Walter L. Cressler
Were All Devonian Seeds Cupulate? A Reinvestigation Of Pseudosporogonites Hallei, Xenotheca Bertrandii, And Aglosperma Spp., Cyrille Prestianni, Jason Hilton, Walter L. Cressler
Earth & Space Sciences Faculty Publications
No abstract provided.
A Study Of Knickpoint Formation: Geomorphic Analysis Of San Simeon Creek, Keith Moffatt
A Study Of Knickpoint Formation: Geomorphic Analysis Of San Simeon Creek, Keith Moffatt
Natural Resources Management and Environmental Sciences
The highest point of orogeny in the Santa Lucia range occurs 50-60km from the nearest active faulting. This orogeny is believed to have occurred hear due to relatively weak Franciscan Mélange versus the granitic material at the fault boundary. This paper studies the development of a knickpoint in San Simeon creek to identify the role of relatively recent (graded time) tectonic activity in orogeny of the Santa Lucia range.
The 2003 earth quake is evidence of recent base level change with the occurrence of orogeny supporting the theory of continuous orogeny in recent and graded time scale. Although the knickpoint …
Examining Antarctica From A Geodynamic Perspective: Backstripping, Ice Thickness, Tectonics And Erosion, Travis Gary Hayden
Examining Antarctica From A Geodynamic Perspective: Backstripping, Ice Thickness, Tectonics And Erosion, Travis Gary Hayden
Dissertations
I have applied the principles of basin analysis and geodynamics to several cores recovered from on or near the Antarctic continent to answer 2 independent questions about the tectonic evolution of Antarctica; as well as estimate the thickness of the Antarctic Ice Sheet at the Last Glacial Maximum.
I developed, and applied a modification of the backstripping modeling technique to compensate for the loading and erosion of glacial ice at the AND-1B site by combining a backstripping driven inverse model, with a driven ice-load model. This modification allowed me to identify and constrain the timing of major pulses of subsidence …
Abundance, Distribution, And Habitat Of The Threatened Minnows Campostoma Ornatum And Notropis Chihuahua In The Trans-Pecos Region Of Texas, Seiji Miyazono, Christopher M. Taylor
Abundance, Distribution, And Habitat Of The Threatened Minnows Campostoma Ornatum And Notropis Chihuahua In The Trans-Pecos Region Of Texas, Seiji Miyazono, Christopher M. Taylor
School of Earth, Environmental, & Marine Sciences Faculty Publications
The Rio Grande and its tributaries in the Trans-Pecos region of Texas have been impacted by a variety of anthropogenic activities such as dewatering and the introduction of nonnative species. These environmental manipulations have negatively affected the native fishes leading to extirpations and declining populations throughout the region. Campostoma ornatum and Notropis chihuahua inhabit tributary streams of the Rio Grande in the Trans-Pecos region and are considered as state-listed threatened species. Little is known about their status and ecological requirements in the region. We hypothesized that the distribution and abundance of these threatened minnows in these spring-fed habitats can be …
Pushing The Envelope? Maize Production Intensification And The Role Of Cattle Manure In Recovery Of Degraded Soils In Smallholder Farming Areas Of Zimbabwe, Leonard Rusinamhodzi, Marc Corbeels, Shamie Zingore, Justice Nyamangara, Ken E. Giller
Pushing The Envelope? Maize Production Intensification And The Role Of Cattle Manure In Recovery Of Degraded Soils In Smallholder Farming Areas Of Zimbabwe, Leonard Rusinamhodzi, Marc Corbeels, Shamie Zingore, Justice Nyamangara, Ken E. Giller
All Peer-Reviewed Publications
Soil fertility decline is a major constraint to crop productivity on smallholder farms in Africa. The objective of this study was to evaluate the long-term (up to nine years) impacts of nutrient management strategies and their local feasibility on crop productivity, soil fertility status and rainfall infiltration on two contrasting soil types and different prior management regimes in Murehwa, Zimbabwe. The nutrient management strategies employed in the study were: a control with no fertiliser, amendments of 100kg Nha-1, 100kg N+lime, three rates of manure application (5, 15 and 25tha-1) in combination with 100kg Nha-1, and three rates of P fertiliser …
Evidence Of Songbird Intoxication From Rozol Application At A Black-Tailed Prairie Dog Colony, Nimish B. Vyas, Craig S. Hulse, Carol U. Meteyer, Clifford P. Rice
Evidence Of Songbird Intoxication From Rozol Application At A Black-Tailed Prairie Dog Colony, Nimish B. Vyas, Craig S. Hulse, Carol U. Meteyer, Clifford P. Rice
United States Geological Survey: Staff Publications
Concerns about avian poisonings from anticoagulant rodenticides have traditionally focused on secondary poisoning of raptors exposed by feeding on contaminated mammalian prey. However, ground foraging songbirds can be directly poisoned from operational applications of the anticoagulant rodenticide RozolH (0.005% chlorophacinone, active ingredient) applied as a grain bait, at black-tailed prairie dog Cynomys ludovicianus colonies. A dead western meadowlark Sturnella neglecta recovered from the study prairie dog colony displayed hemorrhaging in brain and pectoral muscle tissue, and it contained chlorophacinone residue concentrations of 0.59 and 0.49 mg/g (wet weight) in the liver and intestinal contents, respectively. Chlorophacinone residues from two Rozol-colored …
Exploring Connections Between A Very Large Volume Ignimbrite And An Intracaldera Pluton: Intrusions Related To The Oligocene Wah Wah Springs Tuff, Western Us, Chloe Noelle Skidmore
Exploring Connections Between A Very Large Volume Ignimbrite And An Intracaldera Pluton: Intrusions Related To The Oligocene Wah Wah Springs Tuff, Western Us, Chloe Noelle Skidmore
Theses and Dissertations
The Wah Wah Springs Tuff and the Wah Wah Springs Intrusive Granodiorite Porphyry(Wah Wah Springs Intrusion) both originated from the Indian Peak caldera complex, which wasa major focus of explosive silicic activity in the middle Cenozoic Great Basin ignimbrite flareup. This caldera formed 30.0 Ma when an estimated 5,900 km3 of crystal-rich dacitic magma erupted to create the Wah Wah Springs Tuff. The Wah Wah Springs Intrusion later intruded the tuff, causing resurgence of the caldera. Field, modal, and geochemical evidence suggest the tuff and intrusion are cogenetic. The mineral assemblages of the two rocks are similar: both include similar …
Detrital Zircon U/Pb Age Determination: Understanding The Provenance Of The Upper Cretaceous Shumagin Formation, Alaska, Carly F. Roe
Detrital Zircon U/Pb Age Determination: Understanding The Provenance Of The Upper Cretaceous Shumagin Formation, Alaska, Carly F. Roe
Lawrence University Honors Projects
The tectonic evolution of the Chugach-Prince William Terrane (CPW), an accretionary complex along the southern Alaskan margin, has been the subject of much debate. There are two prevailing hypotheses for the location of the CPW at the time of its intrusion by the plutons of the Sanak-Baranof belt, and both require distinctly different source regions for the sediment of the CPW flysch. Therefore, a better understanding of the provenance of these sediments will help constrain the location of the CPW at the time of the deposition of its sediments. This study presents an analysis of new U/Pb detrital zircon, mineralogical …
U.S. Drought Monitor, May 28, 2013, Brad Rippey
U.S. Drought Monitor, May 28, 2013, Brad Rippey
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for May 28, 2013 (5/28/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
White Papers: Drilling Active Tectonics And Magmatism (Volcanics, Geoprisms, And Fault Zones Post-Safod), John W. Shervais, James P. Evans, Amanda Clark, John C. Eichelberger, James Kirkpatrick, Virginia Toy
White Papers: Drilling Active Tectonics And Magmatism (Volcanics, Geoprisms, And Fault Zones Post-Safod), John W. Shervais, James P. Evans, Amanda Clark, John C. Eichelberger, James Kirkpatrick, Virginia Toy
Geosciences Faculty Publications
No abstract provided.
Impacts Of Soil-Acquifer Heat And Water Fluxes On Simulated Global Climate, Nir Krakauer, M. J. Puma, B. I. Cook
Impacts Of Soil-Acquifer Heat And Water Fluxes On Simulated Global Climate, Nir Krakauer, M. J. Puma, B. I. Cook
Publications and Research
Climate models have traditionally only represented heat and water fluxes within relatively shallow soil layers, but there is increasing interest in the possible role of heat and water exchanges with the deeper subsurface. Here, we integrate an idealized 50m deep aquifer into the land surface module of the GISS ModelE general circulation model to test the influence of aquifer-soil moisture and heat exchanges on climate variables. We evaluate the impact on the modeled climate of aquifer-soil heat and water fluxes separately, as well as in combination. The addition of the aquifer to ModelE has limited impact on annual-mean climate, with …
Discontinuities And Alfvenic Fluctuations In The Solar Wind, G. Paschmann, S. Haaland, B. Sonnerup, T. Knetter
Discontinuities And Alfvenic Fluctuations In The Solar Wind, G. Paschmann, S. Haaland, B. Sonnerup, T. Knetter
Dartmouth Scholarship
We examine the Alfvenicity of a set of 188 solar wind directional discontinuities (DDs) identified in the Cluster data from 2003 by Knetter (2005), with the objective of separating rotational discontinuities (RDs) from tangential ones (TDs). The DDs occurred over the full range of solar wind velocities and magnetic shear angles. By performing the Walen test in the de Hoffmann–Teller (HT) frame, we show that 77 of the 127 crossings for which a good HT frame was found had plasma flow speeds exceeding 80 % of the Alfven speed at an average angular deviation of 7.7◦; 33 cases had speeds …
U.S. Drought Monitor, May 21, 2013, Brad Rippey
U.S. Drought Monitor, May 21, 2013, Brad Rippey
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for May 21, 2013 (5/21/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Mechanisms Of Nutrient Limitation And Nutrient Acquisition In Managed And Unmanaged Forest Ecosystems, Matthew A. Vadeboncoeur
Mechanisms Of Nutrient Limitation And Nutrient Acquisition In Managed And Unmanaged Forest Ecosystems, Matthew A. Vadeboncoeur
Doctoral Dissertations
Understanding the interactions between global change, human and natural disturbances, and other factors on biogeochemical processes in forests is necessary to ensure the sustainability of forest management. Here I report the results of several investigations into nutrient acquisition processes in the forests of New Hampshire. I begin with a meta-analysis of fertilization studies showing that phosphorus (P) and calcium (Ca) as well as nitrogen (N) may limit primary production in deciduous forests of the region. Because these limiting nutrients are all removed from the ecosystem when trees are harvested, I compared nutrient budgets under a range of harvesting scenarios with …
U.S. Drought Monitor, May 14, 2013, Rich Tinker
U.S. Drought Monitor, May 14, 2013, Rich Tinker
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for May 14, 2013 (5/14/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Quantifying The Effects Of Pesticide Exposure On Annual Reproductive Success Of Birds, Matthew A. Etterson, Richard S. Bennett
Quantifying The Effects Of Pesticide Exposure On Annual Reproductive Success Of Birds, Matthew A. Etterson, Richard S. Bennett
United States Environmental Protection Agency: Publications
The Markov chain nest productivity model (MCnest) was developed for quantifying the effects of specific pesticide‐use scenarios on the annual reproductive success of simulated populations of birds. Each nesting attempt is divided into a series of discrete phases (e.g., egg laying, incubation, nestling rearing), and results from avian toxicity tests are used to represent the types of effects possible in the field during each breeding phase. The expected exposure dose each day throughout the breeding season can be compared to the toxicity thresholds assigned to each breeding phase to determine whether the nest attempt is at risk. The primary output …
Increasing Ca2+ Deposition In The Western Us: The Role Of Mineral Aerosols, Janice Brahney, Ashley P. Ballantyne, C. Sievers, Jason C. Neff
Increasing Ca2+ Deposition In The Western Us: The Role Of Mineral Aerosols, Janice Brahney, Ashley P. Ballantyne, C. Sievers, Jason C. Neff
Watershed Sciences Faculty Publications
Considerable research has focused on the role of industrial emissions in controlling the acidity of precipitation; however, much less research has focused on the role of mineral aerosols emitted from soils. According to data published by the National Atmospheric Deposition Network (NADP), over the past 17 years Ca2+ deposition has increased over large regions of the US. A trend analysis to determine regions of significant change in Ca2+ deposition revealed statistically significant increases in three broad regions within the western half of the country: the inter-mountain west, the midwest, and the northwest. We evaluated potential changes in sources of calcium …