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Umphlett Qci June 2018, Natalie Umphlett

High Plains Regional Climate Center: Staff Publications

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Odu, Mit Solve And Rise Co-Host Workshop For Local Entrepreneurs Focused On Coastal Resilience Solutions, Betsy Hnath

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Description And Mechanisms Of The Mid-Year Upwelling In The Southern Caribbean Sea From Remote Sensing And Local Data, Digna T. Rueda-Roa, Tal Ezer, Frank E. Muller-Karger

CCPO Publications

The southern Caribbean Sea experiences strong coastal upwelling between December and April due to the seasonal strengthening of the trade winds. A second upwelling was recently detected in the southeastern Caribbean during June-August, when local coastal wind intensities weaken. Using synoptic satellite measurements and in situ data, this mid-year upwelling was characterized in terms of surface and subsurface temperature structures, and its mechanisms were explored. The mid-year upwelling lasts 6-9 weeks with satellite sea surface temperature (SST) ~1-2°C warmer than the primary upwelling. Three possible upwelling mechanisms were analyzed: cross-shore Ekman transport (csET) due to alongshore winds, wind curl (Ekman …

Formation Of Evolved Rocks At Gale Crater By Crystal Fractionation And Implications For Mars Crustal Composition, Arya Udry, Esteban Gazel, Harry Y. Mcsween Jr.

Geoscience Faculty Research

The recent discovery of some ancient evolved rocks in Gale crater by the Curiosity rover has prompted the hypothesis that continental crust formed in early Martian history. Here we present petrological modeling that attempts to explain this lithological diversity by magma fractionation. Using the thermodynamical software MELTS, we model fractional crystallization of different Martian starting compositions that might generate felsic igneous compositions like those analyzed at Gale crater using different variables, such as pressure, oxygen fugacities, and water content. We show that similar chemical and mineralogical compositions observed in Gale crater felsic rocks can readily be obtained through different degrees …

Seasonal Propagation Characteristics Of Mstids Observed At High Latitudes Over Central Alaska Using The Poker Flat Incoherent Scatter Radar, Michael R. Negale, Michael J. Taylor, M. J. Nicolls, Sharon L. Vadas, Kim Nielsen, Craig J. Heinselman

Publications

Near‐continuous electron density measurements obtained over a ∼3 year period, 2010–2013, using the Poker Flat Incoherent Scatter Radar (PFISR) in central Alaska (69°N, 147°W) have been analyzed to quantify the properties of over 650 high‐latitude medium‐scale traveling ionospheric disturbances (MSTIDs). Our analysis focused on the altitude range 100–300 km encompassing the lower ionosphere/thermosphere and yielded first full seasonal day/night distributions of MSTIDs at high northern latitudes with mean values: horizontal wavelength 446 km, horizontal phase speed 187 m/s, and period 41 min. These year‐round measurements fill an important summertime gap in existing MSTID measurements revealing predominantly eastward wave propagation during …

A Diagnostic Metric For Predicting Tropical Cyclone And Mid-Latitude Floods, Jonathon Klepatzki, Shawn M. Milrad

Beyond: Undergraduate Research Journal

This study details a dynamic and thermodynamic metric (i.e., Extreme Flood Index [EFI]) designed to diagnose the frequency and intensity of extreme precipitation events associated with stagnant mid-latitude flow patterns (i.e., Rex blocks). As the global climate warms, rapid Arctic warming may be helping to slow the mid-latitude westerly jet stream, resulting in increased mid-latitude flow stagnation. The combination of long-duration ascent associated with easterly winds and warm moist air increases the severity of extreme precipitation events; as such, the EFI is specifically designed to detect this potent combination of ingredients. In 2013, a Rex block stalled a low-pressure system …

Predicting Spatial Patterns In Precipitation Isotope (Δ2h And Δ18o) Seasonality Using Sinusoidal Isoscapes, Scott T. Allen, James W. Kirchner, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding how precipitation isotopes vary spatially and temporally is important for tracer applications. We tested how well month‐to‐month variations in precipitation δ18O and δ2H were captured by sinusoidal cycles, and how well spatial variations in these seasonal cycles could be predicted, across Switzerland. Sine functions representing seasonal cycles in precipitation isotopes explained between 47% and 94% of the variance in monthly δ18O and δ2H values at each monitoring site. A significant sinusoidal cycle was also observed in line‐conditioned excess. We interpolated the amplitudes, phases, and offsets of these sine functions across the landscape, using multiple linear …

Effect Of Storage Time And Temperature On Germination Ability Of Escoecaria Bussei, F Genes, Agnes Ms Nyomora

Tanzania Journal of Science

This study was conducted in Botany Department Nursery to evaluate the effect of storage time and temperature on germinability of Excoecaria bussei.   The orthodox seeds, collected from Dodoma and Singida regions were germinated monthly from September 2013 through June 2014. Each time, seeds were soaked in water for 6 hours to soften then sown in sterile potting media. A Split-Split plot was used to compare temperature [(15°C) and (30°C)] as main plots, populations (Maktupa, Kisalu and Ilola) as Sub plots and storage time (September 2013 through June 2014) as Sub-Sub-plots on percentage seed germination.  ANOVA revealed average germination percentages of …

Development Of The Wrf-Co2 4d-Var Assimilation System V1.0, Tao Zheng, Nancy H. F. French, Martin Baxter

Michigan Tech Publications, Part 1

Regional atmospheric CO2 inversions commonly use Lagrangian particle trajectory model simulations to calculate the required influence function, which quantifies the sensitivity of a receptor to flux sources. In this paper, an adjoint-based four-dimensional variational (4D-Var) assimilation system, WRF-CO2 4D-Var, is developed to provide an alternative approach. This system is developed based on the Weather Research and Forecasting (WRF) modeling system, including the system coupled to chemistry (WRF-Chem), with tangent linear and adjoint codes (WRFPLUS), and with data assimilation (WRFDA), all in version 3.6. In WRF-CO2 4D-Var, CO2 is modeled as a tracer and its feedback to meteorology is ignored. This …

Adam J. Liska: Curriculum Vitae, Adam Liska

Adam Liska Papers

Associate Professor, George Dempster Smith Chair of Industrial Ecology, Departments of Biological Systems Engineering and Agronomy & Horticulture, University of Nebraska-Lincoln 236 L.W. Chase Hall, Lincoln, NE 68583-0726, Ph: (402) 472-8744, e-mail: [email protected]

Ph.D. 2003 Biology (magna cum laude), Max Planck Institute of Molecular Cell Biology & Genetics, Technische Universität Dresden, Dresden, Germany

Assessing Effective Rhetoric On Twitter In Relation To Forecast Uncertainty In Hurricane Tracks, Erin K. Lynch

Atmospheric & Environmental Sciences

A forecast is only as good as the way it is communicated. As the National Weather Service (NWS) transitions to an Impact-Based Communication style, the new public forecasts discuss how to effectively prepare and protect oneself from harm in the face of severe and significant weather. After severe events, meteorologists need to take the time to analyze the language and style of the rhetoric to assess how effective it was at getting people in harm’s way to take protective actions. It is even more important to understand how information was communicated when there is large uncertainty in the forecast. Uncertainty …

Differences Between High Shear / Low Cape Environments In The Northeast Us Favoring Straight-Line Damaging Winds Versus Tornadoes, Michael E. Main, Ross A. Lazear, Lance F. Bosart

Atmospheric & Environmental Sciences

High shear / low CAPE (HSLC) environments are common in the Northeast US and can occur at any time of year. Severe weather in HSLC environments is notoriously hard to predict, often catching both forecasters and the general public off-guard. The goal of this project is to help forecasters to identify HSLC environments favorable for severe weather in the Northeast US, and to discriminate between HSLC environments that are supportive of tornadoes versus those that favor straight-line damaging winds (SDW). A 10-year HSLC severe weather environmental climatology was created for the Northeast US (New England, New York, New Jersey, Pennsylvania). …

Understanding Microphysical Processes Occurring In Lake-Effect Snowbands Using Quasi-Vertical Profiles Of Wsr-88d Parameters, Marquette Rocque

Atmospheric & Environmental Sciences

Knowing the composition and microphysical processes that occur in lake-effect precipitation systems is important in making sure models capture these processes accurately, and could aid forecasters in predicting snow totals and snow water equivalents. Many studies have shown that processes such as riming and dendritic growth can be seen in dual-polarization radar data through parameters such as equivalent radar reflectivity factor, differential reflectivity (ZDR), correlation coefficient, and differential phase. This research examines WSR-88D data from the KTYX (Montague, NY) radar located on the Tug Hill Plateau for several long-lake-axis-parallel lake-effect systems from the Ontario Winter Lake-effect Systems (OWLeS) field campaign …

Numerical Study Of The Interplay Between Thermo-Topographic Slope Flow And Synoptic Flow On Canopy Transport Processes, Xiyan Xu, Chuixiang Yi, Leonardo Montagnani, Eric Kutter

Publications and Research

Canopy flow resulting from interaction between thermo-topographic slope flow and large-scale synoptic flow is very complicated and has been poorly understood. We apply a Reynolds-averaged Navier-Stokes (RANS) turbulence model to investigate how the interactions between local flow and synoptic winds affect CO₂ movement in the canopy layer at the Renon site in the Italian Alps. Since the RANS simulations are compared to the data measured by multiple-tower experiments conducted during CarboEurope-IP advection campaigns (ADVEX) at Renon, our study can be viewed as a case study of a relatively common wooded slope. The thermal condition in the canopy is directly …

Statistical Analysis And Comparison Of Optical Classification Of Atmospheric Aerosol Lidar Data, Kwasi Gyening Afrifa

Electrical & Computer Engineering Projects for D. Eng. Degree

This dissertation presents a new study for the analysis and classification of atmospheric aerosols in remote sensing LIDAR data. Information on particle size and associated properties are extracted from these remote sensing atmospheric data which are collected by a ground-based LIDAR system. This study first considers optical LIDAR parameter-based classification methods for clustering and classification of different types of harmful aerosol particles in the atmosphere. Since accurate methods for aerosol prediction behaviors are based upon observed data, computational approaches must overcome design limitations, and also consider appropriate calibration and estimation accuracy. Consequently, two statistical methods based on generalized linear models …

Advancing The Understanding Of Environmental Transformations, Bioavailability And Effects Of Nanomaterials, An International Us Environmental Protection Agency—Uk Environmental Nanoscience Initiative Joint Program, Mitch M. Lasat, Kian Fan Chung, Jamie Lead, Steve Mcgrath, Richard J. Owen, Sophie Rocks, Jason M. Unrine, Junfeng Zhang

Plant and Soil Sciences Faculty Publications

Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United …

Atmospheric Radiation And Tgfs: Unexplained Radiation In Our Skies, Adrian Gallegos

Honors College Research

There is a significant correlation between atmospheric electrification via thunderstorms and the occurrence of large emissions of x-ray and gamma ray radiation known as Terrestrial Gamma Ray Flashes (TGFs). Some physical phenomenon may be explained by either the RREA or Thermal Runaway models, but the scientific community as a whole is still largely at work on the theoretical frameworks.

Multidecadal Variability In The Subseasonal Peak Of Low-Level Convergence Over The Pacific Warm Pool, Yen-Heng Lin, Shih-Yu (Simon) Wang

Plants, Soils, and Climate Faculty Publications

In the Western North Pacific (WNP), the atmospheric low-level convergence is one of the main factors that influences the genesis of tropical cyclones (TC). It has been observed that the timing of the seasonal maxima in the low-level convergence and TC genesis has shifted since the mid-1990s from mid-August to late-July, with this shift having also affected the number of TC. A multidecadal frequency of 20 years was revealed in the timing variation of the tropical intraseasonal oscillation (ISO) in the Western Pacific, in which a weak WNP low-level convergence in spring may trigger an advanced ISO phase in summer …

Effects Of Magnetic Fields On An Unsteady Mixed Convective Boundary Layer Flow Of An Electrically Conducting Fluid With Temperature Dependent Properties, Raymond Kitengeso, Eunice Mureithi, Makungu James, John Mango

Tanzania Journal of Science

A mixed convective boundary layer flow of an electrically conducting fluid with temperature dependent properties over an inclined plate is investigated. The magnetohydrodynamic boundary layer governing equations are derived by using Boussinesq and boundary layer approximations. The equations are transformed to similarity form using a similarity transformation variable and the resulting boundary value problem is solved numerically. The effects of magnetic fields, unsteadiness, mixed convection and variable fluid properties on velocity and temperature in the boundary layer are analysed. The effects of pertinent parameters on skin friction and heat transfer are also analysed

Error Analysis Of Multi-Needle Langmuir Probe Measurement Technique, Aroh Barjatya, William Merritt

Publications

Multi-needle Langmuir probe is a fairly new instrument technique that has been flown on several recent sounding rockets and is slated to fly on a subset of QB50 CubeSat constellation. This paper takes a fundamental look into the data analysis procedures used for this instrument to derive absolute electron density. Our calculations suggest that while the technique remains promising, the current data analysis procedures could easily result in errors of 50% or more. We present a simple data analysis adjustment that can reduce errors by at least a factor of five in typical operation.