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2014

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Articles 91 - 120 of 146

Full-Text Articles in Atmospheric Sciences

Impacts Of Aerosol Particle Size Distribution And Land Cover Land Use On Precipitation In A Coastal Urban Environment Using A Cloud-Resolving Mesoscale Model, Nathan Hosannah, Jorge Gonzalez Jan 2014

Impacts Of Aerosol Particle Size Distribution And Land Cover Land Use On Precipitation In A Coastal Urban Environment Using A Cloud-Resolving Mesoscale Model, Nathan Hosannah, Jorge Gonzalez

Publications and Research

Urban environments influence precipitation formation via response to dynamic effects, while aerosols are intrinsically necessary for rainfall formation; however, the partial contributions of each on urban coastal precipitation are not yet known.Here, the authors use aerosol particle size distributions derived from the NASA aerosol robotic network (AERONET) to estimate submicron cloud condensation nuclei (CCN) and supermicron CCN (GCCN) for ingestion in the regional atmospheric modeling system (RAMS). High resolution land data from the National Land Cover Database (NLCD) were assimilated into RAMS to provide modern land cover and land use (LCLU).Thefirst two of eight total simulationswere month long runs for …


Kenyan Climate Variation Assessment Through Rainfall Anomalies And Sea Surface Temperature (Sst) Correlations, Kimberly E. Lykens Jan 2014

Kenyan Climate Variation Assessment Through Rainfall Anomalies And Sea Surface Temperature (Sst) Correlations, Kimberly E. Lykens

STAR Program Research Presentations

The diverse and varied climate of Eastern Africa’s Kenya is home to an agriculturally dependent populace, in which farmers and other related economic sectors make up the majority of livelihoods and gross domestic product. Recurring droughts and severe flooding are major concerns for local farmers and governmental entities. The purpose of this study is to identify and categorize differences in rainfall trends over Kenya and to examine relationships between seasonal rainfall anomalies of sea surface temperature (SST), with an ultimate goal to improve predictions of wet season rainfall amounts. The analysis began with data from 27 national and cooperative weather …


Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Kilic, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu Jan 2014

Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindschadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, Desert Research Institute, Reno, Nv, C. O. Justice, Ayse Kilic, V. Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu

School of Natural Resources: Faculty Publications

Landsat 8, a NASA and USGS collaboration, acquires global moderate-resolution measurements of the Earth's terrestrial and polar regions in the visible, near-infrared, short wave, and thermal infrared. Landsat 8 extends the remarkable 40 year Landsat record and has enhanced capabilities including new spectral bands in the blue and cirrus cloud-detection portion of the spectrum, two thermal bands, improved sensor signal-to-noise performance and associated improvements in radiometric resolution, and an improved duty cycle that allows collection of a significantly greater number of images per day. This paper introduces the current (2012–2017) Landsat Science Team's efforts to establish an initial understanding of …


Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker Jan 2014

Data-Driven Diagnostics Of Terrestrial Carbon Dynamics Over North America, Jingfeng Xiao, Scott V. Ollinger, Steve Frolking, George Hurtt, David Y. Hollinger, Kenneth J. Davis, Yude Pan, Xiaoyang Zhang, Feng Deng, Jiquan Chen, Dennis D. Baldocchi, Beverly E. Law, M. Altaf Arain, Ankur R. Desai, Andrew D. Richardson, Ge Sun, Brian Amiro, Hank Margolis, Lianhong Gu, Russell L. Scott, Peter D. Blanken, Andrew E. Suyker

School of Natural Resources: Faculty Publications

The exchange of carbon dioxide is a key measure of ecosystem metabolism and a critical intersection between the terrestrial biosphere and the Earth’s climate. Despite the general agreement that the terrestrial ecosystems in North America provide a sizeable carbon sink, the size and distribution of the sink remain uncertain. We use a data-driven approach to upscale eddy covariance flux observations from towers to the continental scale by integrating flux observations, meteorology, stand age,aboveground biomass, and a proxy for canopy nitrogen concentrations from AmeriFlux and Fluxnet-Canada Research Network as well as a variety of satellite data streams from the MODIS sensors. …


Estimation Of Crop Gross Primary Production (Gpp): FaparChl Versus Mod15a2 Fpar, Qingyuan Zhang, Yen-Ben Cheng, A. I. Lyapustin, Yujie Wang, Feng Gao, Andrew E. Suyker, Shashi B. Verma, Elizabeth M. Middleton Jan 2014

Estimation Of Crop Gross Primary Production (Gpp): FaparChl Versus Mod15a2 Fpar, Qingyuan Zhang, Yen-Ben Cheng, A. I. Lyapustin, Yujie Wang, Feng Gao, Andrew E. Suyker, Shashi B. Verma, Elizabeth M. Middleton

School of Natural Resources: Faculty Publications

Photosynthesis (PSN) is a pigment level process in which antenna pigments (predominately chlorophylls) in chloroplasts absorb photosynthetically active radiation (PAR) for the photochemical process. PAR absorbed by foliar non-photosynthetic components is not used for PSN. The fraction of PAR absorbed (fAPAR) by a canopy/vegetation (i.e., fAPARcanopy) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) images, referred to as MOD15A2 FPAR, has been used to compute absorbed PAR (APAR) for PSN (APARPSN) which is utilized to produce the standard MODIS gross primary production (GPP) product, referred to as MOD17A2 GPP. In this study, the fraction of PAR …


Representation Of Ethiopian Wet Spells In Global And Nested Models, Mark Jury, Sen Chiao Jan 2014

Representation Of Ethiopian Wet Spells In Global And Nested Models, Mark Jury, Sen Chiao

Faculty Publications, Meteorology and Climate Science

Weather forecast and reanalysis models exhibit different performance in daily rainfall estimation over the Ethiopian highlands, 2000–2012, with ECMWF closer to observations than other models. Background is given to illustrate the Hadley circulation and easterly jets over Ethiopia, using sections on 37°E in July–August 2011. ECMWF reanalysis has a narrow band of rainfall >15 mm/day on 10°N, consistent with TRMM satellite estimates, associated with a steep gradient in meridional wind. MERRA and GFS models have a wider band of rainfall and weaker gradients in meridional winds. The contrasting background states influence a nested WRF model simulation of heavy rain in …


Prescribed Burning Of Logging Slash In The Boreal Forest Of Finland: Emissions And Effects On Meteorological Quantities And Soil Properties, A. Virkkula, J. Levula, T. Pohja, P. Aalto, P. Keronen, S. Schobesberger, Craig Clements, L. Pirjola, A. Kieloaho, L. Kulmala, H. Aaltonen, J. Patoskoski, J. Pumpanen, J. Rinne, T. Ruuskanen, M. Pihlatie, H. Mannien, V. Aaltonen, H. Junninen, T. Petaja, J. Backman, M. Dal Maso, T. Nieminen, T. Olsson, T. Grönholm, J. Aalto, T. Virtanen, M. Kajos, V. Kerminen, D. Shultz, J. Kukkonen, M. Sofiev, G. De Leeuw, J. Back, P. Hari, M. Kulmala Jan 2014

Prescribed Burning Of Logging Slash In The Boreal Forest Of Finland: Emissions And Effects On Meteorological Quantities And Soil Properties, A. Virkkula, J. Levula, T. Pohja, P. Aalto, P. Keronen, S. Schobesberger, Craig Clements, L. Pirjola, A. Kieloaho, L. Kulmala, H. Aaltonen, J. Patoskoski, J. Pumpanen, J. Rinne, T. Ruuskanen, M. Pihlatie, H. Mannien, V. Aaltonen, H. Junninen, T. Petaja, J. Backman, M. Dal Maso, T. Nieminen, T. Olsson, T. Grönholm, J. Aalto, T. Virtanen, M. Kajos, V. Kerminen, D. Shultz, J. Kukkonen, M. Sofiev, G. De Leeuw, J. Back, P. Hari, M. Kulmala

Faculty Publications, Meteorology and Climate Science

A prescribed fire experiment was conducted on 26 June 2009 in Hyytiälä, Finland, to study aerosol and trace gas emissions from prescribed fires of slash fuels and the effects of fire on soil properties in a controlled environment. A 0.8 ha forest near the SMEAR II measurement station (Station for Measuring Ecosystem-Atmosphere Relations) was cut clear; some tree trunks, all tree tops and branches were left on the ground and burned. The amount of burned organic material was ~46.8 tons (i.e., ~60 tons ha−1). The flaming phase lasted 2 h 15 min, the smoldering phase 3 h. Measurements were conducted …


Global Nightly Oh And O2 Mesospheric Airglow: Examining A Decade Of Measurements Using The Nasa Saber Satellite Sensor, Jonathan Price, Jordan C. Rozum, Gene Ware, Doran Baker Jan 2014

Global Nightly Oh And O2 Mesospheric Airglow: Examining A Decade Of Measurements Using The Nasa Saber Satellite Sensor, Jonathan Price, Jordan C. Rozum, Gene Ware, Doran Baker

Browse All Undergraduate research

The SABER instrument aboard the TIMED satellite is a multichannel radiometer and has been continuously measuring the altitude distribution of infrared airglow intensity in the mesosphere on a global basis since 2002. While the majority of these altitude distributions are Gaussian-like, a significant portion exhibit two or more local maxima, suggesting multiple airglow layers. To better understand the cause of this phenomenon, the global and temporal distributions of infrared OH andO2 scans resulting in multiple peak altitude profiles are being examined.


An Advanced Mesospheric Temperature Mapper For High-Latitude Airglow Studies, Pierre-Dominique Pautet, Michael J. Taylor, William R. Pendleton Jr., Yucheng Zhao, Tao Yuan, R. Esplin, D. Mclain Jan 2014

An Advanced Mesospheric Temperature Mapper For High-Latitude Airglow Studies, Pierre-Dominique Pautet, Michael J. Taylor, William R. Pendleton Jr., Yucheng Zhao, Tao Yuan, R. Esplin, D. Mclain

Publications

Over the past 60 years, ground-based remote sensing measurements of the Earth’s mesospheric temperature have been performed using the nighttime hydroxyl (OH) emission, which originates at an altitude of ∼87  km∼87  km. Several types of instruments have been employed to date: spectrometers, Fabry–Perot or Michelson interferometers, scanning-radiometers, and more recently temperature mappers. Most of them measure the mesospheric temperature in a few sample directions and/or with a limited temporal resolution, restricting their research capabilities to the investigation of larger-scale perturbations such as inertial waves, tides, or planetary waves. The Advanced Mesospheric Temperature Mapper (AMTM) is a novel infrared digital imaging …


A Review Of Passive Sampling Systems For Ambient Air Mercury Measurements, Jiaoyan Huang, Seth N. Lyman, Jelena Stamenkovic Hartman, Mae Sexauer Gustin Jan 2014

A Review Of Passive Sampling Systems For Ambient Air Mercury Measurements, Jiaoyan Huang, Seth N. Lyman, Jelena Stamenkovic Hartman, Mae Sexauer Gustin

USU Uintah Basin Faculty Publications

Atmospheric mercury (Hg) temporal and spatial patterns must be measured accurately in order to adequately understand the role of this pathway as it relates to Hg toxicity and exposure of humans and wildlife to Hg. It is also important to understand the distribution of the different chemical forms (elemental, oxidized, or particle bound) and specific compounds in air (e.g., HgCl2, HgBr2, HgO, Hg(NO3)2, and HgSO4). However, the current automated and passive sampling methods of measurement have limitations and artifacts impacting our ability to achieve this task. Both abiotic and biotic systems have been developed to measure the total gaseous Hg …


Investigating The Effect Of The ‘‘Land Between The Lakes’’ On Storm Patterns, Joshua D. Durkee, Ahmed M. Degu, Faisal Hossain, Rezaul Mahmood, Jesse Winchester, Themis Chronis Jan 2014

Investigating The Effect Of The ‘‘Land Between The Lakes’’ On Storm Patterns, Joshua D. Durkee, Ahmed M. Degu, Faisal Hossain, Rezaul Mahmood, Jesse Winchester, Themis Chronis

High Plains Regional Climate Center: Staff Publications

The artificially created region around the ‘‘Land between the Lakes’’ (LBL) in Kentucky represents unique land use and land cover (LULC) heterogeneities. Over a distance of 100 km, the LULC comprises artificially created open water bodies (i.e., two parallel large run-on-river dams separated by the LBL), mountainous terrain, forest cover, and extensive agricultural land. Such heterogeneities increase (decrease) moisture supply and sensible heat, resulting in a differential air mass boundary that helps to initiate (inhibit) convection. Hence, the LBL can potentially modify precipitation formation. Historical anecdotes reveal a tendency for storms to dissipate or reintensify near the LBL. The specific …


A Comparison Of The Mm5 And The Regional Atmospheric Modeling System Simulations For Land--Atmosphere Interactions Under Varying Soil Moisture, Astrid Suarez, Rezaul Mamood, Arturo I. Quintanar, Adriana Beltran-Prezekurat, Roger Pielke Sr. Jan 2014

A Comparison Of The Mm5 And The Regional Atmospheric Modeling System Simulations For Land--Atmosphere Interactions Under Varying Soil Moisture, Astrid Suarez, Rezaul Mamood, Arturo I. Quintanar, Adriana Beltran-Prezekurat, Roger Pielke Sr.

High Plains Regional Climate Center: Staff Publications

A comparison between two mesoscale models, Colorado State University Regional Atmospheric Modeling System (RAMS) version 4.4 coupled with the Land-Ecosystem--Atmosphere Feedback Model (LEAF2) and Penn State/NCAR’s Mesoscale Model (MM5) coupled with NOAH Land Surface Model, was conducted in order to assess the sensitivity of forecasted planetary boundary layer (PBL) variables to anomalous initial volumetric soil moisture conditions. The experiments were conducted using three synoptic events: June 11, 17 and 22, 2006. For each event, one control run and six additional simulations were completed using RAMS and MM5. In each of the events, initial volumetric soil moisture was increased and decreased …


Regional Dust Storm Modeling For Health Services: The Case Of Valley Fever, William A. Sprigg, Slobodan Nickovic, John N. Galgiani, Goran Pejanovic, Slavo Petkovic, Mirjam Vujadinovic, Ana Vukovic, Milan Dacic, Scott Dibiase, Anup K. Prasad, Hesham El-Askary Jan 2014

Regional Dust Storm Modeling For Health Services: The Case Of Valley Fever, William A. Sprigg, Slobodan Nickovic, John N. Galgiani, Goran Pejanovic, Slavo Petkovic, Mirjam Vujadinovic, Ana Vukovic, Milan Dacic, Scott Dibiase, Anup K. Prasad, Hesham El-Askary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

On 5 July 2011, a massive dust storm struck Phoenix, Arizona (USA), raising concerns for increased cases of valley fever (coccidioidomycosis, or, cocci). A quasi-operational experimental airborne dust forecast system predicted the event and provides model output for continuing analysis in collaboration with public health and air quality communities. An objective of this collaboration was to see if a signal in cases of valley fever in the region could be detected and traced to the storm - an American haboob. To better understand the atmospheric life cycle of cocci spores, the DREAM dust model (also herein, NMME-DREAM) was modified to …


Global And Regional Impacts Of Hono On The Chemical Composition Of Clouds And Aerosols, Yasin F. Elshorbany, P. J. Crutzen, B. Steil, A. Pozzer, H. Tost, J. Lelieveld Jan 2014

Global And Regional Impacts Of Hono On The Chemical Composition Of Clouds And Aerosols, Yasin F. Elshorbany, P. J. Crutzen, B. Steil, A. Pozzer, H. Tost, J. Lelieveld

USF St. Petersburg Campus Faculty Publications

Recently, realistic simulation of nitrous acid (HONO) based on the HONO / NOx ratio of 0.02 was found to have a significant impact on the global budgets of HOx (OH + HO2) and gas phase oxidation products in polluted regions, especially in winter when other photolytic sources are of minor importance. It has been reported that chemistry-transport models underestimate sulphate concentrations, mostly during winter. Here we show that simulating realistic HONO levels can significantly enhance aerosol sulphate (S(VI)) due to the increased formation of H2SO4. Even though in-cloud aqueous phase oxidation of dissolved SO2 (S(IV)) is the main source of …


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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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


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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 Jan 2014

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 …