Atmospheric Sciences Commons^™

Civil Engineering Ph.D. Student Puts Virginia Sea Grant Graduate Fellowship To Work On Living Shorelines, Keith Pierce

News Items

No abstract provided.

2017 Costliest Year Ever For Weather-Related Disasters, Betsy Hnath

News Items

No abstract provided.

Global Sea-Level Budget 1993-Present, Wcrp Global Sea Level Budget Group, Benjamin Hamlington

CCPO Publications

Global mean sea level is an integral of changes occurring in the climate system in response to unforced climate variability as well as natural and anthropogenic forcing factors. Its temporal evolution allows changes (e.g.,acceleration) to be detected in one or more components. Study of the sea-level budget provides constraints on missing or poorly known contributions, such as the unsurveyed deep ocean or the still uncertain land water component. In the context of the World Climate Research Programme Grand Challenge entitled "Regional Sea Level and Coastal Impacts", an international effort involving the sea-level community worldwide has been recently initiated with the …

Mls Measurements Of Stratospheric Hydrogen Cyanide During The 2015-2016 El Niño Event, Hugh C. Pumphrey, Norbert Glatthor, Peter F. Bernath, Christopher D. Boone, James W. Hannigan, Ivan Ortega, Nathaniel J. Livesey, William G. Read

Chemistry & Biochemistry Faculty Publications

It is known from ground-based measurements made during the 1982-1983 and 1997-1998 El Niño events that atmospheric hydrogen cyanide (HCN) tends to be higher during such years than at other times. The Microwave Limb Sounder (MLS) on the Aura satellite has been measuring HCN mixing ratios since launch in 2004; the measurements are ongoing at the time of writing. The winter of 2015- 2016 saw the largest El Niño event since 1997-1998. We present MLS measurements of HCN in the lower stratosphere for the Aura mission to date, comparing the 2015- 2016 El Niño period to the rest of the …

Stratospheric Ozone And Hcl Trends (2000-2016): How Significant Is Recent Growth In Chlorinated Very Short-Lived Substances, Ryan Hossaini, Martyn Chipperfield, Peter Bernath, Anton Fernando, Sandip Dhomse, Wuhu Feng

Chemistry & Biochemistry Faculty Publications

[Introduction] Chlorinated very short-lived substances (VSLS), such as dichloromethane (CH₂CL₂), chloroform (CHCl₃₎ and perchloroethylene (C₂Cl₄) constitute a small, but growing source of stratospheric chlorine (e.g. WMO, 2014). High-altitude aircraft observations provide some constraint on the stratospheric source gas injection of chlorine from these compounds, though product gas injection - from VSLS-derived phosgene and HCl produced in the troposphere - is uncertain. Furthermore, in addition to an overall paucity of atmospheric VSLS observations, the impact of VSLS growth on stratospheric composition trends in the recent past (e.g. ozone, HCl) remains poorly constrained.

Analysis Of The Red And Green Optical Absorption Spectrum Of Gas Phase Ammonia, Nikolai F. Zobov, Phillip A. Coles, Roman I. Ovsyannikov, Aleksandra A. Kyuberis, Robert J. Hargreaves, Peter F. Bernath, Jonathan Tennyson, Sergei N. Yurchenko, Oleg L. Polyansky

Chemistry & Biochemistry Faculty Publications

Room temperature NH₃ absorption spectra recorded at the Kitt Peak National Solar Observatory in 1980 are analyzed. The spectra cover two regions in the visible: 15,200 - 15,700 cm^-1 and 17,950 - 18,250 cm^-1. These high overtone rotation-vibration spectra are analyzed using both combination differences and variational line lists. Two variational line lists were computed using the TROVE nuclear motion program: one is based on an ab initio potential energy surface (PES) while the other used a semi-empirical PES. Ab initio dipole moment surfaces are used in both cases. 95 energy levels with J = 1 …

President Broderick's Leadership In Sea Level Rise Initiative Featured In Nation's Top Higher Education Publication, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Community Invited To Discuss King Tide Event, Amy Matzke-Fawcett

News Items

No abstract provided.

Odu Sea Level Rise Initiative Featured In Premier Higher Education Publication, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Community Discussion: Catch The King Tide, Amy Matzke-Fawcett

News Items

No abstract provided.

Deglacial Tropical Atlantic Subsurface Warming Links Ocean Circulation Variability To The West African Monsoon, Matthew W. Schmidt, Ping Chang, Andrew O. Parker, Link Ji, Feng He

OES Faculty Publications

Multiple lines of evidence show that cold stadials in the North Atlantic were accompanied by both reductions in Atlantic Meridional Overturning Circulation (AMOC) and collapses of the West African Monsoon (WAM). Although records of terrestrial change identify abrupt WAM variability across the deglaciation, few studies show how ocean temperatures evolved across the deglaciation. To identify the mechanism linking AMOC to the WAM, we generated a new record of subsurface temperature variability over the last 21 kyr based on Mg/Ca ratios in a sub-thermocline dwelling planktonic foraminifera in an Eastern Equatorial Atlantic (EEA) sediment core from the Niger Delta. Our subsurface …

Life In Hampton Roads: Sea Level Rise And Flooding, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

A Near-Global Atmospheric Distribution Of N2o Isotopologues, Peter F. Bernath, Mahdi Yousefi, Eric Buzan, Chris D. Boone

Chemistry & Biochemistry Faculty Publications

The distributions of the four most abundant isotopologues and isotopomers (N₂O, ¹⁵NNO, N¹⁵NO, and NN¹⁸O of nitrous oxide have been measured in the Earth's stratosphere by infrared remote sensing with the Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer. These satellite observations have provided a near-global picture of N₂O isotopic fractionation. The relative abundances of the heavier species increase with altitude and with latitude in the stratosphere as the air becomes older. The heavy isotopologues are enriched by 20-30% in the upper stratosphere and even more over the poles. These observations are …

Major Hurricane Impact: Is Hampton Roads Ready?, Jon Cawley

News Items

No abstract provided.

Odu Researcher: Hampton Roads A Poster-Child For Sea Level Rise Threat, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Mipas Imk/Iaa Carbon Tetrachloride (Ccl4) Retrieval And First Comparison With Other Instruments, Ellen Eckert, Thomas Von Clarmann, Alexandra Laeng, Gabriele P. Stiller, Bernd Funke, Norbert Glatthor, Udo Grabowski, Sylvia Kellmann, Michael Kiefer, Andrea Linden, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

MIPAS thermal limb emission measurements were used to derive vertically resolved profiles of carbon tetrachloride (CCl₄). Level-1b data versions MIPAS/5.02 to MIPAS/5.06 were converted into volume mixing ratio profiles using the level-2 processor developed at Karlsruhe Institute of Technology (KIT) Institute of Meteorology and Climate Research (IMK) and Consejo Superior de Investigaciones Cientificas (CSIC), Instituto de Astrofisica de Andalucia (IAA). Consideration of peroxyacetyl nitrate (PAN) as an interfering species, which is jointly retrieved, and CO₂ line mixing is crucial for reliable retrievals. Parts of the CO₂ Q-branch region that overlap with the CCl₄ signature were …

High Resolution Spectra Of Carbon Monoxide, Propane And Ammonia For Atmospheric Remote Sensing, Christopher Andrew Beale

OES Theses and Dissertations

Spectroscopy is a critical tool for analyzing atmospheric data. Identification of atmospheric parameters such as temperature, pressure and the existence and concentrations of constituent gases via remote sensing techniques are only possible with spectroscopic data. These form the basis of model atmospheres which may be compared to observations to determine such parameters. To this end, this dissertation explores the spectroscopy of three molecules: ammonia, propane and carbon monoxide.

Infrared spectra have been recorded for ammonia in the region 2400-9000 cm^-1. These spectra were recorded at elevated temperatures (from 293-973 K) using a Fourier Transform Spectrometer (FTS). Comparison between …

Improved Ballistic Wind Prediction Using Projectile Tracking Data, William Arthur Kenney

Computational Modeling & Simulation Engineering Theses & Dissertations

The United States Air Force AC-130 gunships have been in operation since the Vietnam War and have seen frequent use during recent conflicts. They are able to employ gun weapon systems from above a target in a way that maximizes possible time on target. When firing, the gun operators must deal with miss distances caused by winds acting on the projectile in flight. Operators currently perform a “tweak” to predict a ballistic wind affecting fired rounds which is then used in the fire-control to correct for the real winds and bring shots onto target. This correction, a single-point wind prediction, …

Observations Of Greenhouse Gas Isotopologues With Ace-Fts And Waccm, Eric Michael Buzan

Chemistry & Biochemistry Theses & Dissertations

Increases in greenhouse gas concentrations in the atmosphere are the major driver of climate change. Quantifying the sources and sinks of these gases is a major focus of research. Measuring isotopologues, or molecules that differ in isotopic composition, is one useful way of constraining the budget of a molecule as they are highly sensitive to different sources and sinks. However, measurements above the surface have been restricted to a few locations and have only reached the lower stratosphere. Satellite-based remote sensing can achieve nearly global measurement coverage, but so far no satellites have measured isotopologues.

Presented here are measurements of …

Comment On "Using An Adcp To Estimate Turbulent Kinetic Energy Dissipation Rate In Sheltered Coastal Waters", Ann E. Gargett

CCPO Publications

Greene et al. revisit the suggestion that the turbulent kinetic energy dissipation rate could be estimated through a "large-eddy estimate," employing acoustic measurements of velocity fields associated with the largest energy-containing scales of ocean turbulence. While the large-eddy estimate as originally proposed used vertical velocity and a vertical eddy length scale, Greene et al. chose instead to substitute a horizontal length scale for the latter. This comment argues that combining a horizontal scale for length with a vertical velocity scale produces a large-eddy estimate of the dissipation rate that is accurate only if the energy-containing eddies are isotropic, and that …

Depletion Of Ozone And Reservoir Species Of Chlorine And Nitrogen Oxide In The Lower Antarctic Polar Vortex Measured From Aircraft, T. Jurkat, C. Voigt, S. Kaufmann, J.-U. Grooß, H. Ziereis, A. Dörnbrack, P. Hoor, H. Bozem, A. Engel, H. Bönisch, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Novel airborne in situ measurements of inorganic chlorine, nitrogen oxide species, and ozone were performed inside the lower Antarctic polar vortex and at its edge in September 2012. We focus on one flight during the Transport and Composition of the LMS/Earth System Model Validation (TACTS/ESMVal) campaign with the German research aircraft HALO (High-Altitude LOng range research aircraft), reaching latitudes of 65°S and potential temperatures up to 405 K. Using the early winter correlations of reactive trace gases with N₂O from the Atmospheric Chemistry Experiment-Fourier Transform Spectrometer (ACE-FTS), we find high depletion of chlorine reservoir gases up to ∼40% …

Proposed Legislation Seeks To Stimulate Investment In Coastal Resiliency, Jon Cawley

News Items

No abstract provided.

The Role Of Sulfur Dioxide In Stratospheric Aerosol Formation Evaluated By Using In Situ Measurements In The Tropical Lower Stratosphere, A. W. Rollins, T. D. Thornberry, L. A. Watts, P. Yu, K. H. Rosenlof, M. Mills, E. Baumann, F. R. Giorgetta, T. V. Bui, M. Höpfner, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO₂) in maintaining background SAs has been debated for decades without in situ measurements of SO₂ at the tropical tropopause to inform this issue. Here we clarify the role of SO₂ in maintaining SAs by using new in situ SO₂ measurements to evaluate climate models and satellite retrievals. We then use the observed tropical tropopause SO₂ mixing ratios to estimate the global flux of …

A Predictor Analysis Framework For Surface Radiation Budget Reprocessing Using Design Of Experiments, Patricia Allison Quigley

Engineering Management & Systems Engineering Theses & Dissertations

Earth’s Radiation Budget (ERB) is an accounting of all incoming energy from the sun and outgoing energy reflected and radiated to space by earth’s surface and atmosphere. The National Aeronautics and Space Administration (NASA)/Global Energy and Water Cycle Experiment (GEWEX) Surface Radiation Budget (SRB) project produces and archives long-term datasets representative of this energy exchange system on a global scale. The data are comprised of the longwave and shortwave radiative components of the system and is algorithmically derived from satellite and atmospheric assimilation products, and acquired atmospheric data. It is stored as 3-hourly, daily, monthly/3-hourly, and monthly averages of 1°x1° …

Multiple Metabolisms Constrain The Anaerobic Nitrite Budget In The Eastern Tropical South Pacific, Andrew R. Babbin, Brian D. Peters, Calvin W. Mordy, Brittany Widner, Karen L. Casciotti, Bess B. Ward

OES Faculty Publications

The Eastern Tropical South Pacific is one of the three major oxygen deficient zones (ODZs) in the global ocean and is responsible for approximately one third of marine water column nitrogen loss. It is the best studied of the ODZs and, like the others, features a broad nitrite maximum across the low oxygen layer. How the microbial processes that produce and consume nitrite in anoxic waters interact to sustain this feature is unknown. Here we used ¹⁵N-tracer experiments to disentangle five of the biologically mediated processes that control the nitrite pool, including a high-resolution profile of nitrogen loss rates. …

Spaceborne Synthetic Aperture Radar Survey Of Subsidence In Hampton Roads, Virginia (Usa), D.P.S. Bekaert, B. D. Hamlington, B. Buzzanga, C. E. Jones

CCPO Publications

Over the past century, the Hampton Roads area of the Chesapeake Bay region has experienced one of the highest rates of relative sea level rise on the Atlantic coast of the United States. This rate of relative sea level rise results from a combination of land subsidence, which has long been known to be present in the region, and rising seas associated with global warming on long timescales and exacerbated by shifts in ocean dynamics on shorter timescales. An understanding of the current-day magnitude of each component is needed to create accurate projections of future relative sea level rise upon …

Pathways And Supply Of Dissolved Iron In The Amundsen Sea (Antarctica), P. St-Laurent, P. L. Yager, R. M. Sherrell, S. E. Stammerjohn, M. S. Dinniman

CCPO Publications

Numerous coastal polynyas fringe the Antarctic continent and strongly influence the productivity of Antarctic shelf systems. Of the 46 Antarctic coastal polynyas documented in a recent study, the Amundsen Sea Polynya (ASP) stands out as having the highest net primary production per unit area. Incubation experiments suggest that this productivity is partly controlled by the availability of dissolved iron (dFe).As a first step toward understanding the iron supply of the ASP, we introduce four plausible sources of dFe and simulate their steady spatial distribution using conservative numerical tracers. The modeled distributions replicate important features from observations including dFe maxima at …

Observations And Operational Model Simulations Reveal The Impact Of Hurricane Matthew (2016) On The Gulf Stream And Coastal Sea Level, Tal Ezer, Larry P. Atkinson, Robert Tuleya

CCPO Publications

In October 7–9, 2016, Hurricane Matthew moved along the southeastern coast of the U.S., causing major flooding and significant damage, even to locations farther north well away from the storm’s winds. Various observations, such as tide gauge data, cable measurements of the Florida Current (FC) transport, satellite altimeter data and high-frequency radar data, were analyzed to evaluate the impact of the storm. The data show a dramatic decline in the FC flow and increased coastal sea level along the U.S. coast. Weakening of the Gulf Stream (GS) downstream from the storm’s area contributed to high coastal sea levels farther north. …

New And Improved Infra-Red Absorption Cross Sections And Ace-Fts Retrievals Of Carbon Tetrachloride (Ccl4), Jeremy J. Harrison, Christopher D. Boone, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Carbon tetrachloride (CCl₄) is one of the species regulated by the Montreal Protocol on account of its ability to deplete stratospheric ozone. As such, the inconsistency between observations of its abundance and estimated sources and sinks is an important problem requiring urgent attention (Carpenter et al., 2014) [5]. Satellite remote-sensing has a role to play, particularly limb sounders which can provide vertical profiles into the stratosphere and therefore validate stratospheric loss rates in atmospheric models. This work is in two parts. The first describes new and improved high-resolution infra-red absorption cross sections of carbon tetrachloride/dry synthetic air over …

The Hitran2016 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, C. Hill, R. V. Kochanov, Y. Tan, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance

Chemistry & Biochemistry Faculty Publications

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional …