Atmospheric Sciences Commons^™

Atmospheric Circulation Change In The Central Himalayas Indicated By A High-Resolution Ice Core Deuterium Excess Record, Hongxi Pang, Shugui Hou, Susan Kaspari, Paul Mayewski, Douglas Introne, Valérie Masson-Delmotte, Jean Jouzel, Zhenchao Li, Yuanqing He, Sungmin Hong, Dahe Qin

All Faculty Scholarship for the College of the Sciences

Continuous measurements of both δD and δ18O were performed along a 108.8 m ice core recovered from the East Rongbuk Glacier on the northeast saddle of Mt. Qomolangma (Everest) (28.03° N, 86.96° E, 6518 m above sea level) in September 2002. They provide the first high-resolution historical record of deuterium excess (d) in the central Himalayas. In this paper, we focus on d variability from 1951 to 2001 and its relationship with large scale atmospheric circulation. The d record exhibits significant seasonal variations, with low values in summer and high values in winter, reflecting the atmospheric circulation shift between winter …

Gravity Wave Propagation In A Diffusively Separated Gas: Effects On The Total Gas, Michael P. Hickey Ph.D., R. L. Walterscheid

Publications

We present a full-wave model that simulates acoustic-gravity wave propagation in a binary-gas mixture of atomic oxygen and molecular nitrogen, including molecular viscosity and thermal conductivity appropriately partitioned between the two gases. Compositional effects include the collisional transfer of heat and momentum by mutual diffusion between the two gases. An important result of compositional effects is that the velocity and temperature summed over species can be significantly different from the results of one-gas models with the same height dependent mean molecular weight (M(z)). We compare the results of our binary-gas model to two one-gas full-wave models: one where M is …

Large, Long-Lived Convective Systems Over Subtropical South America And Their Relationships With Atmospheric Teleconnections, Kyle Mattingly

Mahurin Honors College Capstone Experience/Thesis Projects

This study provides a climatological assessment of persistent elongated convective systems (PECS) over subtropical South America during the austral warm seasons of 1998-2007 and a comparison of PECS frequency and physical characteristics to mesoscale convective complexes (MCCs) in the region. Relationships between the Antarctic Oscillation (AAO) and El Niño – Southern Oscillation (ENSO) teleconnections and large, long-lived convective systems (LLCSs) are explored. An average of 143 PECS and 37 MCCs occurred per warm season. PECS lasted longer on average than MCCs (17 hrs. vs. 14 hrs.) and reached a greater average maximum cloud-shield extent than MCCs (297,300 km2 vs. 256,500 …

An Evaluation Of Cape Tendency In Tornado Outbreaks, Timothy W. Humphrey, Lance F. Bosart

Atmospheric & Environmental Sciences

Previous studies (e.g., Rasmussen, 2003; Thompson et al., 2003) have examined the impact that instability has on the occurrence of tornadic supercells. However, few studies (e.g., Calas et al., 2000) have examined the impact that the rate of destabilization has on the development of severe convection. Utilizing a CAPE tendency equation derived by Emanuel (1994), this study examines the impact of the rate of atmospheric destabilization on the severity of convection. Comparing six hour analyses of CAPE tendency with observed tornado tracks from the 4-6 May 2007, 5-6 February 2008, and 17 June 2010 tornado outbreaks reveals a potential correlation …

Largescale Precursors To Major Lake Effect Snowstorms Lee Of Lake Erie, Hannah E. Attard, Ross A. Lazear

Atmospheric & Environmental Sciences

Lake‐effect snowstorms are primarily a mesoscale feature; however, major lakeeffect snowstorms are linked closely to their synoptic environment. Thus, a lakeeffect system which lasts for more than 24 h cannot only be explained by the boundary layer; it is also associated with the upper tropospheric flow. This research will address whether major lake‐effect snow events off of Lake Erie can also be associated with large‐scale planetary features several days prior to event onset. The goal is to aid in the forecast process by increasing the accuracy and leadtime of lake‐effect snow forecasts. This study includes 31 cases recorded from the …

The Rapid Intensification Of Hurricane Gustav (2008), Jason H. Keefer

Atmospheric & Environmental Sciences

Hurricane Gustav was one of two major hurricanes that occurred in the Atlantic basin during the 2008 hurricane season. The storm caused more than $6 billion U. S. dollars of damage in Haiti, Jamaica, Cuba, and along the coast of the Gulf of Mexico from 25 August 2008 to 5 September 2008. The greatest amount of damage and highest number of casualties produced by the storm can be attributed to the rapid intensification of the hurricane. Rapid intensification (RI) of a tropical cyclone is defined as an increase in maximum sustained winds by 15.4 m s⁻¹ (30 kts) in a …

Variability Of Black Carbon Deposition To The East Antarctic Plateau, 1800-2000 Ad, M. M. Bisiaux, R. Edwards, J. R. Mcconnell, M. R. Albert

Dartmouth Scholarship

Refractory black carbon aerosols (rBC) from biomass burning and fossil fuel combustion are deposited to the Antarctic ice sheet and preserve a history of emissions and long-range transport from low- and mid-latitudes. Antarctic ice core rBC records may thus provide information with respect to past combustion aerosol emissions and atmospheric circulation. Here, we present six East Antarctic ice core records of rBC concentrations and fluxes covering the last two centuries with approximately annual resolution (cal. yr. 1800 to 2000). The ice cores were drilled in disparate regions of the high East Antarctic ice sheet, at different elevations and net snow …

An Assessment Of The Relationship Between Air Mass Frequency And Extreme Drought In The Midwest United States, Curtis Walker, Erin Potter, Nicholas Esposito, Melissa Godek

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The Midwest of the United States is a region extensively utilized for agriculture and livestock production despite great susceptibility to widespread and persistent drought. While the location and duration of droughts are related to dynamic meteorological factors, pinpointing when and where a drought will commence, how long it will persist, and when the drought will end, remains a challenge. This investigation examines significant Midwest drought events from a synoptic meteorological perspective through an assessment of air mass frequency over the past decade. A synoptic approach is useful since air masses characteristically describe multiple weather and climate parameters at the same …

Observations With The Most Sensitive Rayleigh-Scatter Lidar, Leda Sox, Vincent B. Wickwar, Joshua P. Herron, Marcus J. Bingham

Graduate Student Posters

The mesosphere is the most unexplored region of the atmosphere. Its altitude range of 50-85 km lies in between the reaches of data collecting instruments like weather balloons and satellites. For this reason, remote sensing systems, such as lidar, which are able to employ ground-based instruments to make extensive measurements in this difficult to detect region. The Rayleigh-scatter lidar at USU is currently being redeveloped to be the most powerful and sensitive of its kind. This type of lidar exploits light and particle interactions, like those that account for the blue color of the sky, to make relative density and …

Periodicities Of Peak Current And Flash Multiplicity In Cloud To Ground Lightning, Alexander R. Gibbs

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Research on lightning has been conducted on various topics including thunderstorm electrification and climatology of lightning strikes however; there are still some characteristics of lightning that are not well known, such as flash multiplicity and peak current as a function of individual thunderstorms. These characteristics are the leading cause of injuries and damage each year. This study examines a severe weather event in Minnesota on 16 September 2006, in order to determine what may cause peak current and flash multiplicity. Cycles in peak current and flash multiplicity are identified and then associated with CAPE to determine if a thunderstorm’s updraft …

Droughtscape, Spring 2012, National Drought Mitigation Center

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

Contents

Director’s report.

Climate Masters 1

Ranch plan workshop . 3

Winter climate summary 4

Winter impacts summary . 6

Zhao research.

Getachew research 0

Other international news

Wardlow move 13

IPCC disaster report .

The Carrington Event Not Observed In Most Ice Core Nitrate Records, E W. Wolff, M Bigler, M. A. J. Curran, Jack E. Dibb, M M. Frey, M Legrand, J R. Mcconnell

Earth Sciences

The Carrington Event of 1859 is considered to be among the largest space weather events of the last 150 years. We show that only one out of 14 well-resolved ice core records from Greenland and Antarctica has a nitrate spike dated to 1859. No sharp spikes are observed in the Antarctic cores studied here. In Greenland numerous spikes are observed in the 40 years surrounding 1859, but where other chemistry was measured, all large spikes have the unequivocal signal, including co-located spikes in ammonium, formate, black carbon and vanillic acid, of biomass burning plumes. It seems certain that most spikes …

Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Vegetation and climate both play integral roles in water availability, particularly for arid to semi-arid regions. Changes in these variables can lead to extreme shortages in water for regions that rely on water for crop irrigation (i.e., the Great Plains). The objective of this study is to evaluate the impacts of vegetation on water availability in the Republican River basin in central Nebraska. Decreases in streamflow have been observed in the river basin for many years and, as a result, an invasive riparian plant species (Phragmites australis) is being removed in an effort to reduce evapotranspiration and reclaim …

Ladar Performance Simulations With A High Spectral Resolution Atmospheric Transmittance And Radiance Model- Leedr, Benjamin D. Roth

Theses and Dissertations

In this study of atmospheric effects on Geiger Mode laser ranging and detection (LADAR), the parameter space is explored primarily using the Air Force Institute of Technology Center for Directed Energy's (AFIT/CDE) Laser Environmental Effects Definition and Reference (LEEDR) code. The LADAR system is assessed at operationally representative wavelengths of 1.064, 1.56 and 2.039 μm with several up and down looking engagement geometries at locations worldwide. Results computed with LEEDR are compared to standard atmosphere and Fast Atmospheric Signature Code (FASCODE) assessments. Results show significant climate dependence, but large variances between climatological and standard atmosphere assessments. An overall average absolute …

Unveiling Assigned Amount Unit (Aau) Trades: Current Market Impacts And Prospects For The Future, Elizabeth Lokey Aldrich, Cassandra L. Koerner

CAES Energy Policy Institute Faculty Publications and Presentations

The sale of assigned amount units (AAUs) from countries whose emissions have declined since their baseline year under the Kyoto Protocol has led critics to be skeptical of carbon markets due to the lack of actual emission reductions that occur as a result of these trades. This policy review describes the historical context of AAU trading, current market price and volumes, and environmental and economic impacts of the current AAU trading rules. Options for how to handle current, and prevent the creation of future, surplus AAUs are discussed.

Evaluating Modeled Intra- To Multidecadal Climate Variability Using Running Mann–Whitney Z Statistics, Steven A. Mauget, Eugene C. Cordero, Patrick T. Brown

Faculty Publications, Meteorology and Climate Science

An analysis method previously used to detect observed intra- to multidecadal (IMD) climate regimes was adapted to compare observed and modeled IMD climate variations. Pending the availability of the more appropriate phase 5 Coupled Model Intercomparison Project (CMIP-5) simulations, the method is demonstrated using CMIP-3 model simulations. Although the CMIP-3 experimental design will almost certainly prevent these model runs from reproducing features of historical IMD climate variability, these simulations allow for the demonstration of the method and illustrate how the models and observations disagree. This method samples a time series’s data rankings over moving time windows, converts those ranking sets …

Application Of A Mini-Unmanned Aircraft System For In Situ Monitoring Of Fire Plume Thermodynamics Properties, Caroline Keifer, Craig Clements, Brian Potter

Faculty Publications, Meteorology and Climate Science

Direct measurements of wildland fire plume properties are rare because of difficult access to regions near the fire front and plume. Moisture released from combustion, in addition to added heat, can enhance buoyancy and convection, influencing fire behavior. In this study, a mini unmanned aircraft system (miniUAS) was used to obtain in situ measurements of temperature and relative humidity during a prescribed fire. The miniUAS was successfully maneuvered through the plume and its associated turbulence and provided observations of temperature and humidity profiles from near the centerline of the plume. Within the plume, the water vapor mixing ratio increased by …

Global Variations Of Hdo And Hdo/H2o Ratios In The Upper Troposphere And Lower Stratosphere Derived From Ace-Fts Satellite Measurements, William J. Randel, Elisabeth Moyer, Mijeong Park, Eric Jensen, Peter Bernath

Chemistry & Biochemistry Faculty Publications

High-quality satellite observations of water and deuterated water in the upper troposphere and lower stratosphere (UTLS) from the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS) are used to map global climatological behavior. Spatial and temporal variability in these data suggest that convection plays a significant role in setting water vapor isotopic composition in these regions. In many instances, enhancements in HDO/H₂O (i.e., δD) are closely tied to patterns of climatological deep convection and uncorrelated with water vapor, although convection appears to have different isotopic effects in different locations. The ACE-FTS data reveal seasonal variations in the tropics …

Gravity-Wave-Induced Variations In Exothermic Heating In The Low-Latitude, Equinox Mesophere And Lower Thermosphere Region, Michael P. Hickey Ph.D., Tai-Yin Huang

Publications

We investigate gravity-wave-induced variations in exothermic heating in the OH nightglow region at a latitude of 18° in the Northern and Southern Hemispheres during March. An OH nightglow chemistry model with gravity wavefields from a spectral full-wave model is used for the investigation. Our simulation results show that the wave packet induces a large secular increase in the number densities of the minor species involved in the OH chemistry, a 50% increase in O3, 42% in O, and 29% in OH (v= 8), and the ultimate driver for these increases is the wave-driven downward transport of O. We find that …

Analysis Of Satellite-Derived Arctic Tropospheric Bro Columns In Conjunction With Aircraft Measurements During Arctas And Arcpac, S Choi, Yuhang Wang, R J. Salawitch, T Canty, J Joiner, T Zeng, T P. Kurosu, K Chance, A Richter, L Gregory Huey, J Liao, J A. Neuman, J Nowak, Jack E. Dibb, Andrew Weinheimer, Glenn Diskin, Thomas B. Ryerson, Arlindo Da Silva, J Curry, D Kinnison, S Tilmes, P F. Levelt

Earth Sciences

We derive tropospheric column BrO during the ARCTAS and ARCPAC field campaigns in spring 2008 using retrievals of total column BrO from the satellite UV nadir sensors OMI and GOME-2 using a radiative transfer model and stratospheric column BrO from a photochemical simulation. We conduct a comprehensive comparison of satellite-derived tropospheric BrO column to aircraft in-situ observations of BrO and related species. The aircraft profiles reveal that tropospheric BrO, when present during April 2008, was distributed over a broad range of altitudes rather than being confined to the planetary boundary layer (PBL). Perturbations to the total column resulting from tropospheric …