Oceanography and Atmospheric Sciences and Meteorology Commons^™

Decomposition Of Atmospheric Aerosol Phase Function By Particle Size And Morphology Via Single Particle Scattering Measurements, Kevin B. Aptowicz, Jacqueline Sugar, Sean D. Martin, Richard K. Chang, Elena Fernandez, Yong-Le Pan, Ronald G. Pinnick

Physics & Engineering Faculty Publications

No abstract provided.

Winter Wind Chill Climatology For The High Plains Region, Holly B. Lussenden, Natalie A. Umphlett, Martha D. Shulski, Daniel Ebert

High Plains Regional Climate Center: Staff Publications

During the winter months in the High Plains region of the United States, wind chill temperatures can reach dangerous levels for humans and animals. Knowing the frequency in which extreme wind chill temperatures occur could help forecasters know when to issue wind chill advisories and also the general public understand just how rare, or common, certain wind chill temperatures are. A climatology spanning a 37-year period was created using data from 57 stations in and around the plains portion of the High Plains region from the Integrated Surface Hourly Database at National Climatic Data Center (NCDC). These climatologies were completed …

Climate Masters Of Nebraska: An Innovative Action-Based Approach For Climate Change Education, Tapan Pathak, Tonya Bernadt, Natalie A. Umphlett

High Plains Regional Climate Center: Staff Publications

Climate Masters of Nebraska is an innovative educational program that strategically trains community volunteers about climate change science and corresponding ways to reduce greenhouse gas emissions in an interactive and action-based teaching environment. As a result of the program, 91% of participants indicated that they made informed changes in their lives to reduce greenhouse gas emissions. Approximately 500 hours of volunteer work was reported by participants as an outreach for greenhouse gas emission reduction. The program can be easily replicated to other locales with an effective planning and with small leadership team.

Droughtscape, Winter 2014, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s report

Outlook & quarterly review . 2

Drought in 2013 review.

Quarterly impacts review . 5

Impacts in 2013 review.

Belmont Forum research0

USDM change maps 11

Central Asia drought planning

Kansas RC&D planning

Publication compares plans

Drought for planners webinar

Soil moisture networks

Kansas farm and ranch planning

$500 to develop leadership

Kids seek solutions

Plains symposium April 1-4

The Great 2012 Arctic Ocean Summer Cyclone Enhanced Biological Productivity On The Shelves, Jinlun Zhang, Carin Ashjian, Robert Campbell, Victoria Hill, Yvette H. Spitz, Michael Steele

OES Faculty Publications

A coupled biophysical model is used to examine the impact of the great Arctic cyclone of early August 2012 on the marine planktonic ecosystem in the Pacific sector of the Arctic Ocean (PSA). Model results indicate that the cyclone influences the marine planktonic ecosystem by enhancing productivity on the shelves of the Chukchi, East Siberian, and Laptev seas during the storm. Although the cyclone's passage in the PSA lasted only a few days, the simulated biological effects on the shelves last 1 month or longer. At some locations on the shelves, primary productivity (PP) increases by up to 90% and …

Distinguishing Molecular Characteristics Of Aerosol Water Soluble Organic Matter From The 2011 Trans-North Atlantic Us Geotraces Cruise, A. S. Wozniak, A. S. Willoughby, S. C. Gurganus, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The molecular characteristics of aerosol organic matter (OM) determines to a large extent its impacts on the atmospheric radiative budget and ecosystem function in terrestrial and aquatic environments, yet the OM molecular details of aerosols from different sources are not well established. Aerosol particulate samples with North American-influenced, North African-influenced, and marine (minimal recent continental influence) air mass back trajectories were collected as part of the 2011 trans-North Atlantic US GEOTRACES cruise and analyzed for their water soluble OM (WSOM) molecular characteristics using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Principal component analysis (PCA) separated the samples into …

Global View Of The Role Of The Itcz/Monsoon Trough In Tropical Cyclogenesis, Steven Fuhrman

Legacy Theses & Dissertations (2009 - 2024)

ABSTRACT

Northeast Cool-Season Cyclones Associated With Significant Upper-Level Easterly Wind Anomalies, Adrian Mitchell

Legacy Theses & Dissertations (2009 - 2024)

A subset of Northeast U.S. cool-season cyclones is associated with upper-level easterly flow and, occasionally, well-defined easterly jet streaks. These events occur approximately once per year and may be associated with retrograding surface cyclones and precipitation caused by northerly warm-air advection, leading to forecast challenges. The deepest extratropical cyclone that affected the Northeast U.S. during the 2009-2010 cool-season was associated with an upper-level easterly jet streak, and produced a record snowfall total of 85 cm in Burlington, Vermont. Orographic precipitation enhancement in this case resulted from an interaction of the low-level flow with the complex topography of northern Vermont. This …

Associations Between The Madden-Julian Oscillation, Equatorial Rossby Waves, And Extratropical Northern Hemisphere Predictability, Lawrence Gloeckler

Legacy Theses & Dissertations (2009 - 2024)

The Madden-Julian oscillation (MJO), the leading mode of tropical convective and circulation variability on intraseasonal time scales, has become increasingly leveraged to improve empirical prediction of the global atmospheric circulation. Significant progress has been made in recent years to advance subseasonal (10-30-day) prediction of atmospheric circulation anomalies, and much of this progress can be attributed to the inclusion of information about the phase and amplitude of the MJO in various forecast processes. Despite this progress, however, forecasts based only on the state of the MJO omit information about other important tropical convective and circulation anomalies, and coherent MJO signals are …

Seasonal Variations Of Wind Farm Impacts On Land Surface Temperature And Vegetation Over Northern Illinois, Lauren Slawsky

Legacy Theses & Dissertations (2009 - 2024)

Operating wind turbines enhance near surface turbulence and alter the exchanges of surface energy, water, and momentum, thus affecting local micrometeorology. Climatic impacts of three wind farms in northern Illinois are assessed using land surface temperature (LST) from the Moderate Resolution Imaging Spectroradiometer (MODIS) data onboard the Terra and Aqua satellites for the period 2003-2013. Changes in LST between two periods (before and after construction of the wind turbines) and between wind farm pixels (WFPs) and nearby non wind farm pixels (NNWFPs) are quantified. An increase in LST is observed at nighttime over each wind farm, with the pattern of …

A Climatology Of Central American Gyres, Philippe Pierre Papin

Legacy Theses & Dissertations (2009 - 2024)

Central American gyres (CAGs) are large, low-level, cyclonic circulations that are observed over Central America during the tropical cyclone (TC) season. CAGs often occur in conjunction with TCs, and can result in torrential rainfall over portions of Central America, the Caribbean Islands, and eastern United States. The lack of prior research on CAGs, their apparent links to TC activity, and their association with high- impact weather motivates this study.

Upper-Tropospheric Precursors Associated With Subtropical Cyclone Formation In The North Atlantic Basin, Alicia Marie Bentley

Legacy Theses & Dissertations (2009 - 2024)

Oceanic cyclones exhibiting properties of both tropical and extratropical systems have been categorized as subtropical cyclones (STCs) since the early 1950s. The opportunity to investigate the roles of baroclinic and diabatic processes during the evolution of STCs from a potential vorticity (PV) perspective motivates this study. This study investigates the roles of baroclinic and diabatic processes during the evolution of STCs by calculating three PV metrics from the National Centers for Environmental Prediction Climate Forecast System Reanalysis 0.5° gridded dataset. The three PV metrics quantify the relative contributions of lower-tropospheric baroclinic processes, midtropospheric diabatic heating, and upper-tropospheric dynamical processes during …

An Analysis Of Arctic Climate, The Intense Arctic Cyclone Of Early August 2012, And Middle To High Latitude Snowcover, Adam H. Turchioe

Legacy Theses & Dissertations (2009 - 2024)

On 03 August 2012, a cyclone formed over Central Siberia and progressed northeastwards. By 0000 UTC 05 August, the cyclone reached the Arctic Ocean with a mean sea-level pressure (MSLP) of 984 hPa. Once over the Arctic Ocean, the cyclone rapidly intensified and reached a minimum pressure of 966 hPa on 06 August near 83°N and 170°W. The cyclone slowly weakened, and on 0000 UTC 10 August once again had a minimum MSLP of 984 hPa. The motivation for this presentation is driven by the likelihood that this cyclone is one of the most intense storm systems to ever impact …

On The Mjo And Anticyclonic Wavebreaking, Kyle Macritchie

Legacy Theses & Dissertations (2009 - 2024)

The Madden Julian oscillation (MJO) is the primary mode of intraseasonal variability in the tropics. The MJO often couples with convection as it moves over the Indian Ocean and decouples as it leaves the west Pacific Ocean. The association between convection coupled to the MJO and the midlatitude flow pattern has been the primary focus of numerous studies. In particular, it has been shown that there is a statistical relationship between the position and strength of the MJO and anticyclonic wavebreaking (AWB). This study expands on this statistical relationship by examining, in detail, the two-way relationship between the MJO and …

Spatial And Seasonal Variability Of Cloud Condensation Nuclei Number Concentrations Over The Extended North African Continent And The Mediterranean, Hesham Abdel-Monem Afify Hassan

Legacy Theses & Dissertations (2009 - 2024)

The spatiotemporal variability of cloud condensation nuclei (CCN) number concentration is investigated over the extended domain of the North African continent and Mediterranean which is an essential step for better understanding of aerosol-cloud interactions and associated climate impacts over the region. The study is performed by analyzing the output for the period from 2004 to 2011 from the well-validated global chemistry and aerosol transport model GEOS-Chem-APM. The analysis shows that the dominant aerosol type for CCN number concentration is secondary particles all over the domain. Spatial analysis reveals the existence of four characteristic subdomains of variability: over the Mediterranean and …

A Climatology Of Lower-Stratospheric Fronts Over North America, Hannah Elizabeth Attard

Legacy Theses & Dissertations (2009 - 2024)

A two-part analysis, from a: (1) climatology and composite and (2) case study perspective, were used to examine robust lower-stratospheric fronts identified during eight winter seasons from 2004-2012 in North America. In Part 1, a climatology was constructed from the 184 identified cases of North American lower-stratospheric fronts associated with upper-level jet-front systems. The climatology and composite analyses of these identified cases reveal that there are substantial differences in the environmental characteristics and structure of lower-stratospheric fronts that develop in the Intermountain West and eastern North America regions. These differences exist in all flow directions and suggest that quasigeostrophic diagnostics …

The Spectrum Of Progressive Derecho Formation Environments, Corey Guastini

Legacy Theses & Dissertations (2009 - 2024)

Progressive derechos are severe mesoscale convective systems that often form east of the Rocky Mountains during the warm season (May–August) and cause, by definition, straight-line wind damage along paths upwards of 400 km long. This study develops a subjective, seven-category classification scheme that spans the spectrum of progressive derecho formation environments from those dominated by robust upper-level ridges to those characterized by vigorous upper-level troughs. A climatology of 256 progressive derecho events is created for 1996–2013 and is categorized according to the developed classification scheme. Derecho initiation-relative composites are constructed for each of the seven groups using 0.5° Climate Forecast …

Dynamical And Thermodynamic Processes Contributing To Thundersnow Events Over The Northeast U.S, Kyle Jacob Meier

Legacy Theses & Dissertations (2009 - 2024)

Thundersnow often occurs in conjunction with mesoscale snowbands and may be associated with regions of locally heavy snowfall (15-30 cm) and intense snowfall rates (5-10 cm/h). The availability of the National Lightning Detection Network (NLDN) system and operational Doppler weather radars during the past 20 years has allowed meteorologists to produce comprehensive national lightning maps and to identify localized areas of enhanced snowfall associated with thundersnow. The purpose of this thesis is to take advantage of the NLDN data and other contemporary observing systems in order to construct climatological, composite, and case study analyses of the atmospheric environment during thundersnow …

A Comparative Study Of Sea Level Reconstruction Techniques Using 20 Years Of Satellite Altimetry Data, M. W. Strassburg, B. D. Hamlington, R. R. Leben, K.-Y. Kim

CCPO Publications

Sea level reconstructions extend spatially dense data sets, such as those from satellite altimetry, by decomposing the data set into basis functions and fitting those functions to in situ tide gauge measurements with a longer temporal record. We compare and evaluate two methods for reconstructing sea level through an idealized study. The compared sea level reconstruction methods differ in the technique for calculating basis functions, i.e., empirical orthogonal functions (EOFs) versus cyclostationary EOFs (CSEOFs). Reconstructions are created using Archiving, Validation, and Interpretation of Satellite Oceanographic (AVISO) satellite altimetry data and synthetic tide gauges. Synthetic tide gauge records are simulated using …

Morphology And Mixing State Of Atmospheric Particles: Links To Optical Properties And Cloud Processing, Swarup China

Dissertations, Master's Theses and Master's Reports - Open

Atmospheric particles are ubiquitous in Earth’s atmosphere and impact the environment and the climate while affecting human health and Earth’s radiation balance, and degrading visibility. Atmospheric particles directly affect our planet’s radiation budget by scattering and absorbing solar radiation, and indirectly by interacting with clouds. Single particle morphology (shape, size and internal structure) and mixing state (coating by organic and inorganic material) can significantly influence the particle optical properties as well as various microphysical processes, involving cloud-particle interactions and including heterogeneous ice nucleation and water uptake. Conversely, aerosol cloud processing can affect the morphology and mixing of the particles. For …

Investigating The Role Of The Contact Line In Heterogeneous Nucleation With High Speed Imaging, Colin Gurganus

Dissertations, Master's Theses and Master's Reports - Open

While nucleation of solids in supercooled liquids is ubiquitous [15, 65, 66], surface crystallization, the tendency for freezing to begin preferentially at the liquid-gas interface, has remained puzzling [74, 18, 68, 69, 51, 64, 72, 16]. Here we employ high-speed imaging of supercooled water drops to study the phenomenon of heterogeneous surface crystallization. Our geometry avoids the "point-like contact" of prior experiments by providing a simple, symmetric contact line (triple line defined by the substrate-liquid-air interface) for a drop resting on a homogeneous silicon substrate. We examine three possible mechanisms that might explain these laboratory observations: (i) Line Tension at …

Validation Of Mipas Imk/Iaa V5r_O3_224 Ozone Profiles, A. Laeng, U. Grabowski, T. Von Clarmann, G. Stiller, N. Glatthor, M. Höpfner, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We present the results of an extensive validation program of the most recent version of ozone vertical profiles retrieved with the IMK/IAA (Institute for Meteorology and Climate Research/Instituto de Astrofisica de Andalucia) MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) research level 2 processor from version 5 spectral level 1 data. The time period covered corresponds to the reduced spectral resolution period of the MIPAS instrument, i.e., January 2005-April 2012. The comparison with satellite instruments includes all post-2005 satellite limb and occultation sensors that have measured the vertical profiles of tropospheric and stratospheric ozone: ACE-FTS, GOMOS, HALOE, HIRDLS, MLS, OSIRIS, POAM, …

Global Stratospheric Fluorine Inventory For 2004-2009 From Atmospheric Chemistry Experiment Fourier Transform Spectrometer (Ace-Fts) Measurements And Slimcat Model Simulations, A. T. Brown, M. P. Chipperfield, N. A. D. Richards, C. Boone, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Fluorine-containing species can be extremely effective atmospheric greenhouse gases. We present fluorine budgets using organic and inorganic species retrieved by the ACE-FTS satellite instrument supplemented with output from the SLIMCAT 3-D chemical transport model. The budgets are calculated between 2004 and 2009 for a number of latitude bands: 70-30 °N, 30-00 °N, 00 °N-30 °S, and 30-70°S. At lower altitudes total fluorine profiles are dominated by the contribution from CFC-12, up to an altitude of 20 km in the extra-tropics and 29 km in the tropics; above these altitudes the profiles are dominated by hydrogen fluoride (HF). Our data show …

Technical Note: Swift - A Fast Semi-Empirical Model For Polar Stratospheric Ozone Loss, M. Rex, S. Kremser, P. Huck, G. Bodeker, I. Wohltmann, M. L. Santee, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

An extremely fast model to estimate the degree of stratospheric ozone depletion during polar winters is described. It is based on a set of coupled differential equations that simulate the seasonal evolution of vortex-averaged hydrogen chloride (HCl), nitric acid (HNO3), chlorine nitrate (ClONO₂), active forms of chlorine (ClO_x = Cl+ClO+2ClOOCl) and ozone (O₃) on isentropic levels within the polar vortices. Terms in these equations account for the chemical and physical processes driving the time rate of change of these species. Eight empirical fit coefficients associated with these terms are derived by iteratively fitting the equations …

Derivation Of Tropospheric Methane From Tccon Ch4 And Hf Total Column Observations, K. M. Saad, D. Wunch, P. Bernath, C. Boone, B. Connor, N. M. Deutscher, D.W.T. Griffith, R. Kivi, J. Notholt, C. Roehl, M. Schneider, V. Sherlock, P. O. Wennberg

Chemistry & Biochemistry Faculty Publications

The Total Carbon Column Observing Network (TCCON) is a global ground-based network of Fourier transform spectrometers that produce precise measurements of column-averaged dry-air mole fractions of atmospheric methane (CH₄). Temporal variability in the total column of CH₄ due to stratospheric dynamics obscures fluctuations and trends driven by tropospheric transport and local surface fluxes that are critical for understanding CH₄ sources and sinks. We reduce the contribution of stratospheric variability from the total column average by subtracting an estimate of the stratospheric CH₄ derived from simultaneous measurements of hydrogen fluoride (HF). HF provides a proxy for …

Middle Atmospheric Changes Caused By The January And March 2012 Solar Proton Events, C. H. Jackman, C. E. Randall, V. L. Harvey, S. Wang, E. L. Fleming, M. López-Puertas, B. Funke, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

The recent 23-30 January and 7-11 March 2012 solar proton event (SPE) periods were substantial and caused significant impacts on the middle atmosphere. These were the two largest SPE periods of solar cycle 24 so far. The highly energetic solar protons produced considerable ionization of the neutral atmosphere as well as HOx (H, OH, HO2) and NOx (N, NO, NO2). We compute a NOx production of 1.9 and 2.1 Gigamoles due to these SPE periods in January and March 2012, respectively, which places these SPE periods among the 12 largest in the past 50 yr. Aura Microwave Limb Sounder (MLS) …

Light Scattering From Aerosol Particles In The El Paso Del Norte Region / The Effect Of Humidity, Richard Medina Calderon

Open Access Theses & Dissertations

Atmospheric aerosols play an important role in climate forcing, through scattering and absorption of the incoming solar radiation. The extinction of light by the presence of atmospheric aerosols was studied using two first-principle models, and corresponding computer codes. In the first model the extinction of light from irregularly shaped aerosol particles was analyzed. In the second model it was assumed that the irregularly shaped aerosol particles were covered by a film of water, and the hygroscopicity and the extinction of light by the aerosols was analyzed. These models were then applied to the Paso del Norte region and their light …

Characterizing The Tgt-Lightning Relationship Using Entln, Kareem Omar

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Impact Of Desert Dust And Biomass Burning On The Radiative Budget Of The Sahel, Christopher Phillips

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Two-Source Energy Balance Model To Calculate E, T, And Et: Comparison Of Priestley-Taylor And Penman-Monteith Formulations And Two Time Scaling Methods, Paul D. Colaizzi, Nurit Agam, Judy A. Tolk, Steven R. Evett, Terry A. Howell, Prasanna H. Gowda, Susan A. O'Shaughnessy, William P. Kustas, Martha C. Anderson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The two-source energy balance (TSEB) model calculates the energy balance of the soil-canopy-atmosphere continuum, where transpiration is initially determined by the Priestley-Taylor equation. The TSEB was revised recently using the Penman-Monteith equation to replace the Priestley-Taylor formulation, thus better accounting for the impact of large and varying vapor pressure deficits (VPD) typical of advective, semiarid climates. This study is a comparison of the Priestley- Taylor and Penman-Monteith versions of the TSEB (termed TSEB-PT and TSEB-PM, respectively). Evaporation (E), transpiration (T), and evapotranspiration (ET) calculated by the TSEB-PT and TSEB-PM versions were compared to measurements obtained with microlysimeters, sap flow gauges, …