Stratospheric And Tropospheric Contributions To The Poleward Energy Flux Across 70°N And 65°S In The Merra-2 And Cesm,
2018
University at Albany, State University of New York
Stratospheric And Tropospheric Contributions To The Poleward Energy Flux Across 70°N And 65°S In The Merra-2 And Cesm, Christopher Cardinale
Legacy Theses & Dissertations (2009 - 2024)
The flux of moist static energy (MSE) across 70°N and 65°S plays a key role in the energy budget and climate of the polar regions. This flux, which provides respectively 98 W m⁻² and 91 W m⁻² heating of the northern and southern polar caps, is usually studied from a vertically integrated perspective. Its vertical structure is examined using the NASA-MERRA-2 reanalysis to compute monthly fluxes of sensible, latent and potential energy across 70°N and 65°S for the period 1980-2016. The flux is bimodal, with peaks in the lower troposphere and in the middle stratosphere, and is near zero at …
Understanding The Relationship Between Winter Hawaii Precipitation And North Pacific Climate Variability For Past And Present Climate Conditions,
2018
University at Albany, State University of New York
Understanding The Relationship Between Winter Hawaii Precipitation And North Pacific Climate Variability For Past And Present Climate Conditions, Siyu Li
Legacy Theses & Dissertations (2009 - 2024)
Kona lows (KLs) are a type of seasonal cut-off cyclones in the North Pacific around the Hawaiian Islands during the cold season month (Oct.-Apr.). KLs are important for the annual rainfall budget of the Hawaiian Islands. This study investigates what controls the winter precipitation variability over the Hawaiian Islands in the present-day climate and within a long-term paleoclimate simulation. ERA-interim data from 1979-2014 are used for the present-day analysis of the large-scale circulation. The potential vorticity is used as a measure of extratropical synoptic activity. The Hawaii Rainfall Index is from the Rainfall Atlas of Hawaii (seasonal means, 1920-2012). For …
Influence Of Lightning-Producing Convection On Tropical Cyclone Intensity Change,
2018
University at Albany, State University of New York
Influence Of Lightning-Producing Convection On Tropical Cyclone Intensity Change, Stephanie Stevenson
Legacy Theses & Dissertations (2009 - 2024)
Lightning observations in tropical cyclones (TCs) over the ocean are a recent advance- ment, and while many studies have noted relationships between lightning and TC intensity change, the relationships are not consistent. This dissertation aims to understand the com- plexities of the relationships between lightning and TC intensity change, and associate the relationships to storm kinematic, thermodynamic, and microphysical processes.
Dry Air, Midlevel Flow, And The Persistence Of Deep Convection In Atlantic Tropical Disturbances,
2018
University at Albany, State University of New York
Dry Air, Midlevel Flow, And The Persistence Of Deep Convection In Atlantic Tropical Disturbances, Charles Helms
Legacy Theses & Dissertations (2009 - 2024)
An analysis of dropsonde-observed relative humidity in the Tropical Storm Gabrielle (2013) pregenesis disturbance suggests the presence of a layer of dry air that is being advected into the disturbance from the north. The focus of this study is on this and similar dry air layers, termed dry air inflow pathways (DAIPs), that are characterized by unidirectional disturbance-relative flow drawing dry air into a tropical disturbance. It is hypothesized that DAIPs act to prevent the establishment of persistent deep convection by importing midlevel
The Relationship Between Tropospheric Synoptic-Scale Events, Vertical Wave Activity Flux, And Sudden Stratospheric Warmings In The Boreal Winter,
2018
University at Albany, State University of New York
The Relationship Between Tropospheric Synoptic-Scale Events, Vertical Wave Activity Flux, And Sudden Stratospheric Warmings In The Boreal Winter, Hannah Elizabeth Attard
Legacy Theses & Dissertations (2009 - 2024)
Rapid breakdowns of the climatological mid-winter stratospheric polar vortex [i.e., sudden stratospheric warmings (SSWs)] are often preceded by tropospheric blocks. While some studies suggest that blocks can induce the upward wave activity flux (WAF) through the tropopause region that is necessary to trigger an SSW, other studies show no statistical relationship between tropospheric blocks and SSWs. One objective of this dissertation is to elucidate the dynamical relationship between tropospheric blocks and SSWs by exploring the relationship between blocks and tropopause-level upward WAF. Along with analyzing blocks, this dissertation also explores rapidly deepening extratropical cyclones (i.e., bombs) and tropical cyclones that …
Understanding Large Wind Farm Impacts On Regional Climate And Vegetation Growth From Observational And Modeling Perspectives,
2018
University at Albany, State University of New York
Understanding Large Wind Farm Impacts On Regional Climate And Vegetation Growth From Observational And Modeling Perspectives, Geng Xia
Legacy Theses & Dissertations (2009 - 2024)
In the most recent decade, wind energy has experienced exponential growth worldwide and this rapid increase is expected to continue, particularly over farmlands in the United States. This poses an important question regarding whether the widespread deployment of wind turbines (WTs) will influence surface/near-surface microclimate and vegetation growth. In this dissertation, I investigate the potential wind farm (WF) impacts on regional climate and vegetation growth from both observational and modeling perspectives. High resolution satellite, radiosonde and field observations are used to determine the magnitude and variability of WF-induced changes on surface/near-surface temperatures while the Weather Research and Forecasting (WRF) model …
Field Evaluation Of Portable Air Quality Monitors And Evaluation Of Short-Lived Plume Events Of Atmospheric Pollutants,
2018
University at Albany, State University of New York
Field Evaluation Of Portable Air Quality Monitors And Evaluation Of Short-Lived Plume Events Of Atmospheric Pollutants, Joseph Peter Marto
Legacy Theses & Dissertations (2009 - 2024)
Availability of low cost optical sensors has allowed for the supplementation of existing air quality infrastructure with portable, adaptive monitors. While these sensors generally cannot offer the same accuracy and precision as established analysis methods, they can still reliably detect changes in pollutant concentration. This study evaluates the performance of two portable air quality enclosures deployed at collocated research sites to determine their accuracy and usefulness in field deployments. One system deployed collocated sensors for measurement of particulate matter mass concentration (Thermo pDR 1500 and TSI DustTrak DRX for PM2.5) and the second system deployed sensors for measurement of black …
Tropical Cyclone Rapid Intensification In Environments Of Upper-Tropospheric Troughs : Environmental Influences And Convective Characteristics,
2018
University at Albany, State University of New York
Tropical Cyclone Rapid Intensification In Environments Of Upper-Tropospheric Troughs : Environmental Influences And Convective Characteristics, Michael Fischer
Legacy Theses & Dissertations (2009 - 2024)
Intensity forecasts for tropical cyclones that undergo a period of rapid intensification are particularly susceptible to large errors. For those storms that interact with an upper-tropospheric trough, tropical cyclone intensity forecasts are complicated, as upper-tropospheric troughs can provide unique intensification mechanisms, but are often associated with unfavorable environmental conditions. Although tropical cyclones in environments with nearby upper-tropospheric troughs are associated with lesser intensification rates than tropical cyclones in environments devoid of upper-tropospheric troughs, some tropical cyclone--trough interactions are associated with a period of rapid intensification. This dissertation utilizes reanalysis output, satellite observations, and ensemble modeling simulations to understand whether rapid …
Global Response To The Madden-Julian Oscillation As A Function Of Phase Speed In Era-Interim Reanalysis And Miroc5 Model Data,
2018
University at Albany, State University of New York
Global Response To The Madden-Julian Oscillation As A Function Of Phase Speed In Era-Interim Reanalysis And Miroc5 Model Data, Kaitlyn Krzyzaniak
Legacy Theses & Dissertations (2009 - 2024)
Many authors state that the phase speed of the Madden–Julian oscillation (MJO) is near 5ms–1, but observations suggest it varies considerably. MJO propagation typically sets off Rossby wave trains that interact with and alter this extratropical pattern; however, differences in the MJO phase speed could alter the Rossby wave response, leading to a unique response in the extratropics. An understanding of the mechanisms and extratropical responses to variable MJO phase speeds would provide innovative and invaluable insight for subseasonal forecasting.
The Upper-Level Turbulence, Static Stability And Tropopause Structure Of Tropical Cyclones,
2018
University at Albany, State University of New York
The Upper-Level Turbulence, Static Stability And Tropopause Structure Of Tropical Cyclones, Patrick Duran
Legacy Theses & Dissertations (2009 - 2024)
Upper-tropospheric thermodynamic processes can play an important role in tropical cyclone (TC) structure and evolution. Despite its importance, until recently few in-situ observations were available in the upper levels of TCs. Two recent field campaigns -- the National Aeronautics and Space Administration (NASA) Hurricane and Severe Storm Sentinel (HS3) and the Office of Naval Research Tropical Cyclone Intensity (TCI) experiment -- provided a wealth of high-altitude observations within TCs. These observations revealed that the upper-level static stability and tropopause structure of TCs can change dramatically with both space and time.
An Analysis Of The Linkages Between Large-Scale Flow Regime Transitions On The Spatiotemporal Distribution Of Clustered Extratropical Cyclone Events Over The Northern Hemisphere,
2018
University at Albany, State University of New York
An Analysis Of The Linkages Between Large-Scale Flow Regime Transitions On The Spatiotemporal Distribution Of Clustered Extratropical Cyclone Events Over The Northern Hemisphere, Eric Merton John Bunker
Legacy Theses & Dissertations (2009 - 2024)
An Analysis of the Linkages Between Large-Scale Flow Regime Transitions on the Spatiotemporal Distribution of Clustered Extratropical Cyclone Events over the Northern Hemisphere
What Affects The Phase Speed Of Madden-Julian Oscillation Convection,
2018
University at Albany, State University of New York
What Affects The Phase Speed Of Madden-Julian Oscillation Convection, Robert Setzenfand
Legacy Theses & Dissertations (2009 - 2024)
The Madden-Julian Oscillation (MJO) is the main source of convective and circulation variability on intraseasonal timescales and planetary spatial scales within the tropics. Although the phase speed of the MJO convective envelope is often stated as 5 m s–1, MJO events that occur over the Indo-Pacific warm pool can have a range of phase speeds. This study uses a wavelet to identify MJO convective events with specified phase speeds in a satellite-derived outgoing longwave radiation (OLR) dataset during boreal winter. The wavelet-filtered OLR index is then regressed against basic meteorological variables to extract information about MJO events or signals propagating …
Predictability Of African Easterly Waves In An Operational Ensemble Prediction System,
2018
University at Albany, State University of New York
Predictability Of African Easterly Waves In An Operational Ensemble Prediction System, Travis J. Elless
Legacy Theses & Dissertations (2009 - 2024)
African easterly waves (AEWs) are the primary synoptic-scale weather feature found in sub-Saharan Africa during boreal summer. Many studies have used observations and idealized models to highlight processes associated with the movement and growth of AEWs, yet there have been few studies documenting the performance of operational ensemble prediction systems (EPSs) for these phenomena. Here, the predictability of AEWs in ECMWF EPS forecasts is assessed during two periods of enhanced AEW activity (July--September 2007--2009 and 2011--2013). Specifically, AEW predictability is analyzed through three main areas of focus: 1) verifying AEW position and intensity forecasts, and assessing their relation to convective …
Projected Changes In Climate, Elevation-Dependent Warming, And Extreme Events Over Continental Ecuador For The Period 2041-2070,
2018
University at Albany, State University of New York
Projected Changes In Climate, Elevation-Dependent Warming, And Extreme Events Over Continental Ecuador For The Period 2041-2070, Oscar Chimborazo
Legacy Theses & Dissertations (2009 - 2024)
The climate over Ecuador is complex due to several interacting factors, such as its location at the equator, the Andean topography, and several modes of internal variability, including the El Niño–Southern Oscillation (ENSO), affecting the region. In addition, the rapid increase in greenhouse gas concentrations will continue to affect both the mean state and climate variability in Ecuador over the coming decades. Hence, a thorough understanding of both natural and anthropogenic forcings and how they combine to influence Ecuadorian climate is a necessity for decision-making and implementation of adequate adaptation measures. However, the lack of observational data, both in space …
Whole-Canopy Net Ecosystem Exchange And Water Use Efficiency In An Intermittent-Light Environment -- Dynamic Approach,
2018
University at Albany, State University of New York
Whole-Canopy Net Ecosystem Exchange And Water Use Efficiency In An Intermittent-Light Environment -- Dynamic Approach, Sergey Nikolayevich Kivalov
Legacy Theses & Dissertations (2009 - 2024)
An observed 20-30% increase in forest net ecosystem exchange (NEE) on partly cloudy days is often attributed to there being more uniform canopy illumination by diffuse radiation when clouds are present. However, the sky on such days is typically populated by fair-weather cumulus clouds, bringing dynamically changing shadow-to-light conditions on the order of minutes to the forest, with radiation alternating from 1000 W m^-2 in the clear sky to less than 400 W m^-2 in under-cloud shadows. These dynamically changing conditions cannot be investigated by the conventional time-averaged eddy-covariance flux method, which requires nearly steady-state turbulent conditions over much longer …
Polar Ozone Depletion: Mario J. Molina,
2018
Parkland College
Polar Ozone Depletion: Mario J. Molina, Kirsten Oberg
Natural Sciences Student Research Presentations
This poster for the Natural Sciences Poster Session at Parkland College features the contribution of Mario J. Molina to the field of atmospheric chemistry, especially in regards to the formation and decomposition aspects of the ozone layer.
Biomass Burning In The Conterminous United States: A Comparison And Fusion Of Active Fire Observations From Polar-Orbiting And Geostationary Satellites For Emissions Estimation,
2018
South Dakota State University
Biomass Burning In The Conterminous United States: A Comparison And Fusion Of Active Fire Observations From Polar-Orbiting And Geostationary Satellites For Emissions Estimation, Fangjun Li
Electronic Theses and Dissertations
Biomass burning is an important source of atmospheric greenhouse gases and aerosol emissions that significantly influence climate and air quality. Estimation of biomassburning emissions (BBE) has been limited to the conventional method in which parameters (i.e., burned area and fuel load) can be challenging to quantify accurately. Recent studies have demonstrated that the rate of biomass combustion is a linear function of fire radiative power (FRP), the instantaneous radiative energy released from actively burning fires, which provides a novel pathway to estimate BBE. To obtain accurate and timely BBE estimates for near real-time applications (i.e., air quality forecast), the satellite …
Mls Measurements Of Stratospheric Hydrogen Cyanide During The 2015-2016 El Niño Event,
2018
Old Dominion University
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,
2018
Lancaster Environment Centre
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,
2018
Old Dominion University
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 …
