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2012

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Full-Text Articles in Physical Sciences and Mathematics

Interactions Of Aqueous Ag+ With Fulvic Acids: Mechanisms Of Silver Nanoparticle Formation And Investigation Of Stability, Nathaniel F. Adegboyega, Virender K. Sharma, Karolina Siskova, Radek Zboril, Mary Sohn, Brian J. Schultz, Sarbajit Banerjee Dec 2012

Interactions Of Aqueous Ag+ With Fulvic Acids: Mechanisms Of Silver Nanoparticle Formation And Investigation Of Stability, Nathaniel F. Adegboyega, Virender K. Sharma, Karolina Siskova, Radek Zboril, Mary Sohn, Brian J. Schultz, Sarbajit Banerjee

Chemistry and Chemical Engineering Faculty Publications

This study investigated the possible natural formation of silver nanoparticles (AgNPs) in Ag+ −fulvic acid (FA) solutions under various environmentally relevant conditions (temperature, pH, and UV light). Increase in temperature (24−90 °C) and pH (6.1−9.0) of Ag+ −Suwannee River fulvic acid (SRFA) solutions accelerated the appearance of the characteristic surface plasmon resonance (SPR) of AgNPs. The rate of AgNP formation via reduction of Ag+ in the presence of different FAs (SRFA, Pahokee Peat fulvic acid, PPFA, Nordic lake fulvic acid, NLFA) and Suwannee River humic acid (SRHA) followed the order NLFA > SRHA > PPFA > SRFA. This order was found to be …


Seasonal Dimorphism In The Horny Bills Of Sparrows, Russell Greenberg, Matthew Etterson, Raymond M. Danner Dec 2012

Seasonal Dimorphism In The Horny Bills Of Sparrows, Russell Greenberg, Matthew Etterson, Raymond M. Danner

United States Environmental Protection Agency: Staff Publications

Bill size is often viewed as a species-specific adaptation for feeding, but it sometimes varies between sexes, suggesting that sexual selection or intersexual competition may also be important. Hypotheses to explain sexual dimorphism in avian bill size include divergence in feeding niche or thermoregulatory demands, intrasexual selection based on increased competition among males, or female preference. Birds also show seasonal changes in bill size due to shifts in the balance between growth rate and wear, which may be due to diet or endogenous rhythms in growth. Insight into the function of dimorphism can be gained using the novel approach of …


U.S. Drought Monitor, December 11, 2012, Rich Tinker Dec 2012

U.S. Drought Monitor, December 11, 2012, Rich Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 11, 2012 (12/11/12) 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: Hay, Cattle, Winter wheat.


A Regionalized National Universal Kriging Model Using Partial Least Squares Regression For Estimating Annual Pm2.5 Concentrations In Epidemiology, Paul D. Sampson, Mark Richards, Adam A. Szpiro, Silas Bergen, Lianne Sheppard, Timothy V. Larson, Joel Kaufman Dec 2012

A Regionalized National Universal Kriging Model Using Partial Least Squares Regression For Estimating Annual Pm2.5 Concentrations In Epidemiology, Paul D. Sampson, Mark Richards, Adam A. Szpiro, Silas Bergen, Lianne Sheppard, Timothy V. Larson, Joel Kaufman

UW Biostatistics Working Paper Series

Many cohort studies in environmental epidemiology require accurate modeling and prediction of fine scale spatial variation in ambient air quality across the U.S. This modeling requires the use of small spatial scale geographic or “land use” regression covariates and some degree of spatial smoothing. Furthermore, the details of the prediction of air quality by land use regression and the spatial variation in ambient air quality not explained by this regression should be allowed to vary across the continent due to the large scale heterogeneity in topography, climate, and sources of air pollution. This paper introduces a regionalized national universal kriging …


Symbolic Model-Checking Of Stateful Timed Csp Using Bdd And Digitization, Truong Khanh Nguyen, Jun Sun, Yang Liu, Jin Song Dong Dec 2012

Symbolic Model-Checking Of Stateful Timed Csp Using Bdd And Digitization, Truong Khanh Nguyen, Jun Sun, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Stateful Timed CSP has been recently proposed to model (and verify) hierarchical real-time systems. It is an expressive modeling language which combines data structure/operations, complicated control flows (modeled using compositional process operators adopted from Timed CSP), and real-time requirements like deadline and within. It has been shown that Stateful Timed CSP is equivalent to closed timed automata with silent transitions, which implies that the timing constraints of Stateful Timed CSP can be captured using explicit tick events, through digitization. In order to tackle the state space explosion problem, we develop a BDD-based symbolic model checking approach to verify Stateful Timed …


A Centre-Stable Manifold For The Energy-Critical Wave Equation In R^3 In The Symmetric Setting, Marius Beceanu Dec 2012

A Centre-Stable Manifold For The Energy-Critical Wave Equation In R^3 In The Symmetric Setting, Marius Beceanu

Mathematics and Statistics Faculty Scholarship

Consider the focusing semilinear wave equation in R^3 with energy-critical nonlinearity \partial_t^2 \psi - \Delta \psi - \psi^5 = 0, \psi(0) = \psi_0, \partial_t \psi(0) = \psi_1. This equation admits stationary solutions of the form \phi(x, a) := (3a)^{1/4} (1+a|x|^2)^{-1/2}, called solitons, which solve the elliptic equation -\Delta \phi - \phi^5 = 0. Restricting ourselves to the space of symmetric solutions \psi for which \psi(x) = \psi(-x), we find a local centre-stable manifold, in a neighborhood of \phi(x, 1), for this wave equation in the weighted Sobolev space ^{-1} \dot H^1 \times< x>^{-1} L^2. Solutions with initial data on the …


Walmart's Sustainability Journey: Andy Ruben And The Design Of Organizational Structures And Systems (B), David G. Hyatt, Andrew Spicer Dec 2012

Walmart's Sustainability Journey: Andy Ruben And The Design Of Organizational Structures And Systems (B), David G. Hyatt, Andrew Spicer

Wal-Mart Sustainability Case Project

The case “Andy Ruben and the Design of Strategic Goals and Processes” flows from the previous discussion, by moving from the development of an ambitious vision to the challenges of adopting strategic policies and processes to reach those aspirations in practice. This case puts students into the role of Andy Ruben, Walmart’s first Vice-President for Sustainability , asking them to make concrete decisions about what should be done, in what order, and by what process if they were to implement an ambitious corporate sustainability strategy. In the case, Ruben confronts specific choices about how to define the responsibilities of the …


Walmart's Sustainability Journey: Lee Scott's Founding Vision, Andrew Spicer, Laura Lambdin Dec 2012

Walmart's Sustainability Journey: Lee Scott's Founding Vision, Andrew Spicer, Laura Lambdin

Wal-Mart Sustainability Case Project

The first case—“Lee Scott’s Founding Vision”—takes the perspective from the apex of the organization as Walmart’s CEO, Lee Scott, develops and articulates his vision of what Walmart hopes to achieve by pursuing an aggressive sustainability strategy. This case explores the pressures that led Scott to announce the company’s ambitious sustainability goals: achieving zero waste, 100% renewable energy, and selling sustainable products. It also explores the choices made when defining and communicating the scope of the strategy, particularly through an in-depth analysis of his announcement of Walmart’s new goals in his October 2005, “Twenty-First Century Leadership” speech.


Walmart's Sustainability Journey: Andy Ruben And The Design Of Organizaional Structures And Systems (A), Andrew Spicer, Laura Lambdin Dec 2012

Walmart's Sustainability Journey: Andy Ruben And The Design Of Organizaional Structures And Systems (A), Andrew Spicer, Laura Lambdin

Wal-Mart Sustainability Case Project

The case “Andy Ruben and the Design of Strategic Goals and Processes” flows from the previous discussion, by moving from the development of an ambitious vision to the challenges of adopting strategic policies and processes to reach those aspirations in practice. This case puts students into the role of Andy Ruben, Walmart’s first Vice-President for Sustainability , asking them to make concrete decisions about what should be done, in what order, and by what process if they were to implement an ambitious corporate sustainability strategy. In the case, Ruben confronts specific choices about how to define the responsibilities of the …


Consumers And Sustainability At Walmart: A Student's Perspective, Kealy Carter, Satish Jayachandran Dec 2012

Consumers And Sustainability At Walmart: A Student's Perspective, Kealy Carter, Satish Jayachandran

Wal-Mart Sustainability Case Project

To further encourage students to analyze initial goals in comparison with outcomes over time, we have developed a consumer-oriented case—“Consumers and Sustainability at Walmart: A Student’s Perspective”—that moves beyond the perspective of internal Walmart participants to explores issues of sustainability from the point of view of a typical Walmart shopper. In this case, we examine the experience of a fictional student shopper who goes to Walmart and wants to buy sustainable products, which helps raise questions for students about what Walmart’s actions mean to them as consumers, citizens as well as business professionals. The case also asks students to evaluate …


Walmart's Sustainability Journey: Defining Sustainable Products (B), David G. Hyatt, Andrew Spicer Dec 2012

Walmart's Sustainability Journey: Defining Sustainable Products (B), David G. Hyatt, Andrew Spicer

Wal-Mart Sustainability Case Project

In “Defining Sustainable Products (A),” we examine Walmart’s search for a systemic solution to define a sustainable product precisely. In this case, Matt Kistler, who succeeded Andy Ruben as the company sustainability leader in 2007, knows that the company is lagging behind on its espoused goal of selling sustainable products. The case asks students step into Kistler’s shoes as he leads Walmart’s sustainability office through a systematic review of the different models and frameworks available for measuring the sustainability of products presently in use. Eventually, the students face a decision about what Walmart should do to make systemic progress with …


Walmart's Sustainability Journey: Defining Sustainable Products (A), David G. Hyatt, Andrew Spicer Dec 2012

Walmart's Sustainability Journey: Defining Sustainable Products (A), David G. Hyatt, Andrew Spicer

Wal-Mart Sustainability Case Project

In “Defining Sustainable Products (A),” we examine Walmart’s search for a systemic solution to define a sustainable product precisely. In this case, Matt Kistler, who succeeded Andy Ruben as the company sustainability leader in 2007, knows that the company is lagging behind on its espoused goal of selling sustainable products. The case asks students step into Kistler’s shoes as he leads Walmart’s sustainability office through a systematic review of the different models and frameworks available for measuring the sustainability of products presently in use. Eventually, the students face a decision about what Walmart should do to make systemic progress with …


Walmart's Sustainability Journey: Peter Redmond And The Search For Sustainable Seafood, David G. Hyatt Dec 2012

Walmart's Sustainability Journey: Peter Redmond And The Search For Sustainable Seafood, David G. Hyatt

Wal-Mart Sustainability Case Project

In “Peter Redmond and the Search for Sustainable Seafood,” students examine the responses of Peter Redmond, Vice President and Divisional Merchandise Manager of Deli and Seafood, to organizational pressures to make seafood more sustainable at Walmart.


Lake Padden Monitoring Project 2012 Final Report, Robin A. Matthews, Joan Vandersypen, Laura Junge Dec 2012

Lake Padden Monitoring Project 2012 Final Report, Robin A. Matthews, Joan Vandersypen, Laura Junge

Lake Padden

The Lake Padden monitoring project was initiated in 2011 by the citizens group, People for Lake Padden (P4LP), to provide an intensive water quality study of Lake Padden. Water samples were collected between June and December 2011 by AndrewMajeske, a student intern working with the Institute forWatershed Studies (IWS) and the Nooksack Salmon Enhancement Association (NSEA). The results from this project were summarized by Majeske et al. (2012). The water quality monitoring was funded for a second year by P4LP, which provided funding for IWS student intern Laura Junge. Additional funding was provided by the City of Bellingham to identify …


Cloud Computing For Environment-Friendly Data Centers, Michael Pawlish, Aparna Varde, Stefan Robila Dec 2012

Cloud Computing For Environment-Friendly Data Centers, Michael Pawlish, Aparna Varde, Stefan Robila

Department of Computer Science Faculty Scholarship and Creative Works

The purpose of this paper is to analyze the carbon footprint and utilization rates in a data center. The long-term goal of this work is to give data center administrators an enhanced perspective of data center operations to allow for more energy efficient operation, to lower the carbon footprint, and to promote green data centers. Previous literature shows that low utilization rates in data centers are due to the forecasting of demand to meet spikes in data center use. This management policy has led to many servers running idle the majority of the time which is a waste of resources. …


Ferroelectric Instability Under Screened Coulomb Interactions, Yong Wang, Xiaohui Liu, John D. Burton, Sitaram S. Jaswal, Evgeny Y. Tsymbal Dec 2012

Ferroelectric Instability Under Screened Coulomb Interactions, Yong Wang, Xiaohui Liu, John D. Burton, Sitaram S. Jaswal, Evgeny Y. Tsymbal

Evgeny Tsymbal Publications

We explore the effect of charge carrier doping on ferroelectricity using density functional calculations and phenomenological modeling. By considering a prototypical ferroelectric material, BaTiO3, we demonstrate that ferroelectric displacements are sustained up to the critical concentration of 0.11 electron per unit cell volume. This result is consistent with experimental observations and reveals that the ferroelectric phase and conductivity can coexist. Our investigations show that the ferroelectric instability requires only a short-range portion of the Coulomb force with an interaction range of the order of the lattice constant. These results provide a new insight into the origin of ferroelectricity …


Bf2obn∙Oet2: A Novel Lewis Acid And Its Use In A Regio- And Stereo-Selective Opening Of Trisubstituted Epoxides And Its Application Towards Amphidinolide C, Nicholas A. Morra, Brian Pagenkopf Dec 2012

Bf2obn∙Oet2: A Novel Lewis Acid And Its Use In A Regio- And Stereo-Selective Opening Of Trisubstituted Epoxides And Its Application Towards Amphidinolide C, Nicholas A. Morra, Brian Pagenkopf

Chemistry Publications

The generation of a new Lewis acid (BF2OBn·OEt2) has been reported, and its usefulness has been demonstrated in the regio- and stereoselective ring-opening of trisubstituted epoxides. This Lewis acid is one in a series of new Lewis acids generated from BF3·OEt2 that display varying levels of Lewis acidity. When paired with a modified Shi epoxidation protocol, highly functionalized propionate units, such as those found in a wide variety of natural products, can be accessed. In conjunction with a Mukaiyama oxidative cyclization employing our second generation catalyst Co(nmp)2, this procedure ultimately culminated in the shortest and highest yielding route towards the …


Changes In Thermospheric Temperature Induced By High-Speed Solar Wind Streams, Larry Gardner, Jan Josef Sojka, Robert W. Schunk, Rod Heelis Dec 2012

Changes In Thermospheric Temperature Induced By High-Speed Solar Wind Streams, Larry Gardner, Jan Josef Sojka, Robert W. Schunk, Rod Heelis

All Physics Faculty Publications

During high-speed stream (HSS) events the solar wind speed increases, and the cross polar cap potential increases, leading to increased Joule heating at high latitudes. The heat input at high latitudes heats the polar regions, which then conducts to lower latitudes, producing global heating. The heating occurs during the risetime of the cross polar cap potential and throughout the period of high cross polar cap potential as seen in our simulation. These simulations are performed using the Utah State University global thermosphere model driven by Joule heating rates that are consistent with electric fields observed by DMSP-15 observations of HSS …


Unresolved Question Of The 10he Ground State Resonance, Z. Kohley, J. Snyder, T. Baumann, G. Christian, P.A. Deyoung, J.E. Finck, R.A. Haring-Kaye, M. Jones, E. Lunderberg, B. Luther, S. Mosby, A. Simon, J.K. Smith, A. Spyrou, Sharon L. Stephenson, M. Thoennessen Dec 2012

Unresolved Question Of The 10he Ground State Resonance, Z. Kohley, J. Snyder, T. Baumann, G. Christian, P.A. Deyoung, J.E. Finck, R.A. Haring-Kaye, M. Jones, E. Lunderberg, B. Luther, S. Mosby, A. Simon, J.K. Smith, A. Spyrou, Sharon L. Stephenson, M. Thoennessen

Physics and Astronomy Faculty Publications

The group state of 10He was populated using a 2p2n-removal from a 59 MeV/u 14Be beam. The decay energy of the three body system, 8He + n + n, was measured and a resonance was observed at E = 1.60(25) MeV with a 1.8(4) MeV width. This result is in agreement with previous invariant mass spectroscopy measurements, using the 11Li(-p) reaction, but is consistent with recent transfer reaction results. The proposed explanation that the difference, about 500 keV, is due to the effect of the extended halo nature of 11Li in the one-proton knockout reaction is …


The Fierce Green Fire: Vol. 3 Issue 12, Wofford College Environmental Studies Program Dec 2012

The Fierce Green Fire: Vol. 3 Issue 12, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Agenda: The Future Of Natural Resources Policy, University Of Colorado Boulder. Natural Resources Law Center Dec 2012

Agenda: The Future Of Natural Resources Policy, University Of Colorado Boulder. Natural Resources Law Center

The Future of Natural Resources Policy (December 6)

This forum will provide a post-election perspective on some of the challenges and opportunities that natural resources, public lands, and energy policymakers in Washington are likely to face in the next four years. An expert panel will discuss the dynamics in the Department of the Interior, the Department of Agriculture, and Congress, and how their evolving policies are likely to affect Colorado in the coming years.

Moderator: Dean Phil Weiser, University of Colorado Law School

Panelists:

Jay Jensen, Associate Director for Land & Water Ecosystems, White House Council on Environmental Quality

Scott Miller, Visiting Assistant Professor, University of Colorado Law …


Background Reading: Department Of The Interior, 2013 Departmental Overview, United States. Department Of The Interior, Ken Salazar Dec 2012

Background Reading: Department Of The Interior, 2013 Departmental Overview, United States. Department Of The Interior, Ken Salazar

The Future of Natural Resources Policy (December 6)

18 pages (DO-5 through DO-22).

"Background Reading"

The Future of Natural Resources Policy: This forum will provide a post-election perspective on some of the challenges and opportunities that natural resources, public lands, and energy policymakers in Washington are likely to face in the next four years. An expert panel will discuss the dynamics in the Department of the Interior, the Department of Agriculture, and Congress, and how their evolving policies are likely to affect Colorado in the coming years.


Background Reading: Department Of Agriculture, 2013 Budget Overview, United States. Forest Service, United States. Department Of Agriculture Dec 2012

Background Reading: Department Of Agriculture, 2013 Budget Overview, United States. Forest Service, United States. Department Of Agriculture

The Future of Natural Resources Policy (December 6)

57 pages.

"Fiscal Year 2013 Budget Overview"

"February 2012"

"Background Reading"

The Future of Natural Resources Policy: This forum will provide a post-election perspective on some of the challenges and opportunities that natural resources, public lands, and energy policymakers in Washington are likely to face in the next four years. An expert panel will discuss the dynamics in the Department of the Interior, the Department of Agriculture, and Congress, and how their evolving policies are likely to affect Colorado in the coming years.


Dissolved Organic Matter Composition And Bioavailability Reflect Ecosystem Productivity In The Western Arctic Ocean, Yuan Shen, Cedric Fichot, Ronald Benner Dec 2012

Dissolved Organic Matter Composition And Bioavailability Reflect Ecosystem Productivity In The Western Arctic Ocean, Yuan Shen, Cedric Fichot, Ronald Benner

Faculty Publications

Dissolved organic carbon (DOC) and total dissolved amino acids (TDAA) were measured in high (Chukchi Sea) and low (Beaufort Sea) productivity regions of the western Arctic Ocean to investigate the composition and bioavailability of dissolved organic matter (DOM). Concentrations and DOC-normalized yields of TDAA in Chukchi surface waters were relatively high, indicating an accumulation of bioavailable DOM. High concentrations and yields of TDAA were also observed in the upper halocline of slope and basin waters, indicating off-shelf transport of bioavailable DOM from the Chukchi Sea. In contrast, concentrations and yields of TDAA in Beaufort surface waters were relatively low, indicting …


Sensitivity Analysis For Causal Inference Under Unmeasured Confounding And Measurement Error Problems, Iván Díaz, Mark J. Van Der Laan Dec 2012

Sensitivity Analysis For Causal Inference Under Unmeasured Confounding And Measurement Error Problems, Iván Díaz, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

In this paper we present a sensitivity analysis for drawing inferences about parameters that are not estimable from observed data without additional assumptions. We present the methodology using two different examples: a causal parameter that is not identifiable due to violations of the randomization assumption, and a parameter that is not estimable in the nonparametric model due to measurement error. Existing methods for tackling these problems assume a parametric model for the type of violation to the identifiability assumption, and require the development of new estimators and inference for every new model. The method we present can be used in …


Computationally Efficient Confidence Intervals For Cross-Validated Area Under The Roc Curve Estimates, Erin Ledell, Maya L. Petersen, Mark J. Van Der Laan Dec 2012

Computationally Efficient Confidence Intervals For Cross-Validated Area Under The Roc Curve Estimates, Erin Ledell, Maya L. Petersen, Mark J. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

In binary classification problems, the area under the ROC curve (AUC), is an effective means of measuring the performance of your model. Most often, cross-validation is also used, in order to assess how the results will generalize to an independent data set. In order to evaluate the quality of an estimate for cross-validated AUC, we must obtain an estimate for its variance. For massive data sets, the process of generating a single performance estimate can be computationally expensive. Additionally, when using a complex prediction method, calculating the cross-validated AUC on even a relatively small data set can still require a …


A National Model Built With Partial Least Squares And Universal Kriging And Bootstrap-Based Measurement Error Correction Techniques: An Application To The Multi-Ethnic Study Of Atherosclerosis, Silas Bergen, Lianne Sheppard, Paul D. Sampson, Sun-Young Kim, Mark Richards, Sverre Vedal, Joel Kaufman, Adam A. Szpiro Dec 2012

A National Model Built With Partial Least Squares And Universal Kriging And Bootstrap-Based Measurement Error Correction Techniques: An Application To The Multi-Ethnic Study Of Atherosclerosis, Silas Bergen, Lianne Sheppard, Paul D. Sampson, Sun-Young Kim, Mark Richards, Sverre Vedal, Joel Kaufman, Adam A. Szpiro

UW Biostatistics Working Paper Series

Studies estimating health effects of long-term air pollution exposure often use a two-stage approach, building exposure models to assign individual-level exposures which are then used in regression analyses. This requires accurate exposure modeling and careful treatment of exposure measurement error. To illustrate the importance of carefully accounting for exposure model characteristics in two-stage air pollution studies, we consider a case study based on data from the Multi-Ethnic Study of Atherosclerosis (MESA). We present national spatial exposure models that use partial least squares and universal kriging to estimate annual average concentrations of four PM2.5 components: elemental carbon (EC), organic carbon (OC), …


College Of Engineering Senior Design Competition Fall 2012, University Of Nevada, Las Vegas Dec 2012

College Of Engineering Senior Design Competition Fall 2012, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Senior Design Experience

Part of every UNLV engineering student's academic experience, the Senior Design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs and prototypes a product in this required element of the curriculum. Working in teams, the senior design project encourages students to use everything learned in the engineering and computer design programs to create a practical, real world solution to an engineering challenge.

Beyond the classroom ...

Because of the requirement to work in teams, students also build good communication skills, presentation skills and even business writing skills. They also have to …


Spatial Filter Approach To Evaluating The Role Of Convection On The Evolution Of A Mesoscale Vortex, Glenn A. Creighton, Robert E. Hart, Philip Cunningham Dec 2012

Spatial Filter Approach To Evaluating The Role Of Convection On The Evolution Of A Mesoscale Vortex, Glenn A. Creighton, Robert E. Hart, Philip Cunningham

Department of Earth and Atmospheric Sciences: Faculty Publications

A new spatial filter is proposed that exploits a spectral gap in power between the convective scale and the system (‘‘vortex’’) scale during tropical cyclone (TC) genesis simulations. Using this spatial separation, this study analyzes idealized three-dimensional numerical simulations of deep moist convection in the presence of a symmetric midlevel vortex to quantify and understand the energy cascade between the objectively defined convective scale and system scale during the early stages of tropical cyclogenesis. The simulations neglect surface momentum, heat, and moisture fluxes to focus on generation and enhancement of vorticity within the interior to more completely close off the …


U.S. Drought Monitor, December 4, 2012, Rich Tinker Dec 2012

U.S. Drought Monitor, December 4, 2012, Rich Tinker

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 4, 2012 (12/4/12) 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: Hay, Cattle, Winter wheat.