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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

The Contributions Of Dynamical And Diabatic Processes Preceding And Accompanying Major Greenland Ice-Melt Events, Scott Feldman Dec 2021

The Contributions Of Dynamical And Diabatic Processes Preceding And Accompanying Major Greenland Ice-Melt Events, Scott Feldman

Legacy Theses & Dissertations (2009 - 2024)

Extratropical cyclones and/or short-wave disturbances can reinforce Greenland blocking through upper-level flow amplification and can increase poleward heat and moisture transport into the Arctic. Increased poleward heat and moisture transport into the Arctic may enhance Greenland ice melt during the spring, summer, and fall months. The need to better understand the underlying dynamical and diabatic processes that may contribute to Greenland ice melt motivates this thesis. The purpose of this thesis is to investigate: 1) the role of advective warming due to poleward heat and moisture transport into the Arctic in facilitating Greenland ice melt, 2) the role of adiabatic …


The Impacts Of Transported Wildfire Smoke Aerosol On Surface Air Quality In New York State, Wei-Ting Hung Dec 2021

The Impacts Of Transported Wildfire Smoke Aerosol On Surface Air Quality In New York State, Wei-Ting Hung

Legacy Theses & Dissertations (2009 - 2024)

In New York State (NYS), summertime long-range transported smoke plumes and high fine mode particulate matter (PM2.5) concentration during the smoke episodes have been reported. Since the frequency, intensity, and burned area of wildfires over Northern America have increased in recent years, the contribution of transported smoke aerosols to local air quality could become more significant. This study aimed to characterize the transport of smoke aerosols and quantify their impacts on the local air quality over NYS. A case study of a transported smoke event in mid-August of 2018 and multi-year analysis of the smoke cases during the summer seasons …


The Effect Of Differential Friction On Tropical Cyclone Development Close To Land, Minghao Zhou Aug 2021

The Effect Of Differential Friction On Tropical Cyclone Development Close To Land, Minghao Zhou

Legacy Theses & Dissertations (2009 - 2024)

Hurricane Karl (2010) underwent unexpected rapid intensification in the Bay of Campeche while remaining in close proximity (within 150 km) to land. It is hypothesized that the frictionally-enhanced inflow contributed positively to this evolution, despite reduced surface fluxes and increased momentum loss over land. In this study, the role of differential friction in the development of a tropical cyclone (TC) tracking parallel to a coastline is examined based on this prototype.A series of high-resolution, semi-idealized numerical simulations with full physics were conducted on a β-plane with curvature effects of the Earth. After initializing a TC from a synoptic-scale thermal perturbation, …


Exploring Environmental And Methodological Sensitivities Of Forecasted And Observed Surface Winds And Gusts Using Underutilized Datasets, Alex Roslyn Gallagher Aug 2021

Exploring Environmental And Methodological Sensitivities Of Forecasted And Observed Surface Winds And Gusts Using Underutilized Datasets, Alex Roslyn Gallagher

Legacy Theses & Dissertations (2009 - 2024)

Accurate forecasts and reliable observations of surface mean winds and gusts inhabit a vast and essential role in meteorological applications that range from wind energy, atmospheric transport, fire weather, and hazard assessment. This dissertation aims to address and explore known shortfalls in the prediction of mean winds and gusts as well as enhance evaluation and understanding of observed surface wind measurements. A variety of forecasts, methodologies, and observational dataset, many of which have been previously un- or under-utilized, are leveraged to tackle the differing needs of assessing mean winds, gusts, and the surface environment.Detailed verifications of HRRR (version 3 and …


Objective Methodology To Identify The Sea Breeze Circulation And Associated Low-Level Jet In The New York Bight, Elizabeth J. Mccabe Aug 2021

Objective Methodology To Identify The Sea Breeze Circulation And Associated Low-Level Jet In The New York Bight, Elizabeth J. Mccabe

Legacy Theses & Dissertations (2009 - 2024)

While the sea breeze has been studied for decades, in a complicated mid-latitude coastal region such as the New York Bight (NYB), the general thermodynamic structure and dynamics of the circulation is poorly characterized. The East Coast of the United States has become a critical area for offshore wind farm development, including a generally favorable wind resource, relatively shallow waters on an extensive continental shelf, frequent warm season sea breezes, and proximity to large populated areas. Thus the sea breeze will play a key role in the new energy economy, given the favorable wind speeds and capacity factors during periods …


It Takes Two To Tango : Understanding The Processes That Lead To Simultaneous Changes In Tropical Cyclone Intensity And Size And Communicating The Associated Hazards To Emergency Managers, Emily A. Paltz Aug 2021

It Takes Two To Tango : Understanding The Processes That Lead To Simultaneous Changes In Tropical Cyclone Intensity And Size And Communicating The Associated Hazards To Emergency Managers, Emily A. Paltz

Legacy Theses & Dissertations (2009 - 2024)

The severity of tropical cyclone (TC) hazards is modulated by both TC intensity and size. More intense TCs produce stronger storm surges and increase wind damage. Larger TCs potentially impact more people, increase the duration of TC hazards, produce stronger storm surges and increase the amount of rainfall and flooding. Thus, accurately forecasting both TC intensity and size and effectively communicating those forecasts are critical to properly preparing communities for TC impacts. Forecast accuracy can be improved by enhancing our understanding about the processes that cause changes in TC intensity and size. This research divides the Extended Best Track dataset …


Theoretical And Observational Analysis Of Ice Particles For Improvement Of Ice Microphysical Models, Vanessa Przybylo Aug 2021

Theoretical And Observational Analysis Of Ice Particles For Improvement Of Ice Microphysical Models, Vanessa Przybylo

Legacy Theses & Dissertations (2009 - 2024)

Frozen hydrometeors can grow to acquire a multitude of shapes and sizes, which influence the distribution of mass within cloud systems. Aggregates have a variety of formations based on initial ice particle size, shape, falling orientation, and the number of particles that collect. This work employs the theoretical Ice Particle and Aggregate Simulator (IPAS) as a statistical tool to repetitively collect ice crystals to derive bulk aggregate characteristics.


Predictability Issues Associated With Near-Freezing Precipitation Type In Complex Terrain, Matthew Seymour Aug 2021

Predictability Issues Associated With Near-Freezing Precipitation Type In Complex Terrain, Matthew Seymour

Legacy Theses & Dissertations (2009 - 2024)

Predictability challenges are heightened in winter weather forecasting when the environment for high-impact weather is marginal or varies over short distances. High-resolution numerical weather prediction (NWP), such as the High-Resolution Rapid Refresh (HRRR), and ensemble forecast systems, such as the Global Ensemble Forecast System (GEFS), are useful for constraining forecasts. However, their use can be challenging in marginal, near-freezing, situations when precipitation type is uncertain. Uncertainties in planetary boundary layer (PBL) and microphysics (MP) parameterizations and subtle synoptic-scale model errors brought on by differences in initial and lateral boundary conditions (IC/BCs) complicate the p-type forecast. Further, complex terrain, such as …


A Mechanism For Upscale Growth Of Convection In The Complex Terrain Of The Northeast U.S, Brennan Joseph Stutsrim Aug 2021

A Mechanism For Upscale Growth Of Convection In The Complex Terrain Of The Northeast U.S, Brennan Joseph Stutsrim

Legacy Theses & Dissertations (2009 - 2024)

Upstate New York has a variety of complex terrain that can interact with the background flow to create mesoscale heterogeneities in the lower troposphere. The major valleys of Upstate New York, the Hudson and Mohawk Valleys, often have increased moisture content and stronger surface winds than the higher terrain surrounding them. These features can have a profound effect on the evolution of convective storms, especially in cases characterized by low-to-moderate shear, which tends to favor pulse-like or multicellular convection. Analysis of composite radar imagery has indicated that convective storms often change mode while descending from the Catskills Mountains into the …


Diagnosing High Sinuosity Regimes Associated With Anomalous Greenland Ice-Melt Events Using Self-Organizing Maps, Mansour El Riachy May 2021

Diagnosing High Sinuosity Regimes Associated With Anomalous Greenland Ice-Melt Events Using Self-Organizing Maps, Mansour El Riachy

Legacy Theses & Dissertations (2009 - 2024)

Sinuosity, a metric that describes the waviness of the circumpolar flow, is adapted to quantify modification of the tropospheric polar vortex within longitudinal sectors by localized incursions of warm, moist air from middle latitudes associated with Arctic cyclones (ACs). In this thesis, we identify four corridors of high AC track frequency, on which we center 90° longitudinal sectors comprising the following regions: Pacific, West of Greenland, Atlantic, and Asian. Sectorial sinuosity is calculated for the West of Greenland sector and is used to quantify the amplitude of the 300-hPa flow associated with anomalous Greenland ice-melt events.


On The Structure And Phase Speeds Of The Kelvin Waves And Mjo Over The Indian Ocean, Ahmed Shaaban May 2021

On The Structure And Phase Speeds Of The Kelvin Waves And Mjo Over The Indian Ocean, Ahmed Shaaban

Legacy Theses & Dissertations (2009 - 2024)

Kelvin waves in the stratosphere are well known to behave as radiative gravity waves. Yet, the tropospheric component of these Kelvin waves (and other tropical modes) has often been described as superpositions between the baroclinic modes. By decomposing the Kelvin waves into upward and downward-phase components, we found that only upward-phase Kelvin waves occupy the troposphere, indicating that the tropospheric Kelvin waves are not vertical standing oscillations as previously thought. Fast Kelvin waves were found to obey the structure of radiating gravity waves, like their stratospheric counterpart, more than the moist waves. The unexpected lack of variation in vertical tilt …


Seasonal Differences In The Impacts Of Ipo And Amo On Temperature And Precipitation Over South America, Thomas Favata May 2021

Seasonal Differences In The Impacts Of Ipo And Amo On Temperature And Precipitation Over South America, Thomas Favata

Legacy Theses & Dissertations (2009 - 2024)

The Atlantic Multidecadal Oscillation (AMO) and Interdecadal Pacific Oscillation (IPO) have been shown to impact temperature and precipitation across the globe. However, the seasonal differences in their impacts are not well studied. This study analyzes the seasonal differences in the impacts of the AMO and IPO on South American temperature and precipitation. Observational and reanalysis data with enough temporal coverage to isolate the multidecadal modes were used first to identify the regions impacted by the AMO and IPO through a correlation analysis. Then Empirical Orthogonal Functions (EOF) and a Maximum Covariance Analysis (MCA) were used to determine the seasonal spatial …


An Examination Of The Arctic Environment And Arctic Cyclones During Periods Of Low And High Forecast Skill Of The Synoptic-Scale Flow, Kevin Biernat Jan 2021

An Examination Of The Arctic Environment And Arctic Cyclones During Periods Of Low And High Forecast Skill Of The Synoptic-Scale Flow, Kevin Biernat

Legacy Theses & Dissertations (2009 - 2024)

This dissertation compares Arctic environmental conditions and Arctic cyclones (ACs) between periods of low and high forecast skill of the synoptic-scale flow over the Arctic during summer, hereafter referred to as low-skill periods and high-skill periods, respectively. This dissertation also examines features and processes influencing the evolution and forecast skill of selected categories of ACs.


A Comparison Of The Upscale Influence Of Various Planetary Boundary Layer Turbulence Parameterizations On The Evolution Of Extratropical Cyclones, Matthew Vaughan Jan 2021

A Comparison Of The Upscale Influence Of Various Planetary Boundary Layer Turbulence Parameterizations On The Evolution Of Extratropical Cyclones, Matthew Vaughan

Legacy Theses & Dissertations (2009 - 2024)

Subgrid-scale turbulence in numerical weather prediction models is typically handled by a PBL parameterization. These schemes attempt to represent turbulent mixing processes occurring below the resolvable scale of the model grid in the vertical direction, and they act upon temperature, moisture, and momentum within the boundary layer. This dissertation utilizes idealized and full-physics numerical model simulations to understand how variations in turbulent mixing parameterizations may influence sensible weather forecasts of baroclinic cyclones across a variety of spatial and temporal scales. Furthermore, a primary pathway through which PBL turbulence projects upscale during baroclinic cyclone events is identified using a combination of …


Seasonal Variations And Long-Term Trend Of Mineral Dust And The Effects Of Dust On Cloud And Precipitations, Yanda Zhang Jan 2021

Seasonal Variations And Long-Term Trend Of Mineral Dust And The Effects Of Dust On Cloud And Precipitations, Yanda Zhang

Legacy Theses & Dissertations (2009 - 2024)

For its enormous emission rate and long-range transport ability, mineral dust is one of the most abundant aerosol species, contributing to about half of the global atmospheric aerosol dry mass burden. A series of studies demonstrated the significant influences of mineral dust on air quality, public health, biogeochemical cycles, and climate systems. In the atmosphere, mineral dust is known to have important impacts on the Earth system through direct effects (scattering and absorbing shortwave and longwave radiations), semi-direct effects (changing atmospheric temperature structure and cloud lifetime), and indirect effects (influencing cloud microphysics processes as cloud condensation nuclei (CCN) and ice-nucleating …


Aerosol And Terrain Effects On Winter Cloud And Precipitation Over New York State, Yuyi Du Jan 2021

Aerosol And Terrain Effects On Winter Cloud And Precipitation Over New York State, Yuyi Du

Legacy Theses & Dissertations (2009 - 2024)

Prediction of regional weather and climate regarding precipitation for a region such as the Northeast US with its complex terrain and aerosol environment constitutes a major challenge. Furthermore, complex thermodynamic structures occur in and around New York State (NYS) owing to its complex topography paired with its coastal regions, ultimately affecting cloud and precipitation microphysics. The microphysical processes within the weather systems that produce orographic precipitation are not fully understood. These processes include, but are not limited to, liquid-ice interactions, ice growth through vapor deposition, riming, and aggregation, cloud-aerosol interactions, and melting and refreezing upon sedimentation to the surface. These …


The Sensitivity Of Convection To Boundary Layer Parameterization In Hurricanes Harvey And Irma 2017, Dylan Card Jan 2021

The Sensitivity Of Convection To Boundary Layer Parameterization In Hurricanes Harvey And Irma 2017, Dylan Card

Legacy Theses & Dissertations (2009 - 2024)

Tropical cyclones (TCs) pose a significant threat to life and property, and exhibit many severe weather hazards as they make landfall, such as storm surge, strong winds, flooding rains, and tornadoes. TC convection is associated with nearly all of these hazards, which can extend hundreds of kilometers inland; thus, understanding the characteristics and organization of convective cells is important to mitigating risk. Observational studies have noted that TC convection tends to organize downshear and that rotating thunderstorms tend to occur in the downshear-right quadrant of the TC. Modeling studies have also shown that convective cells tend to form upshear right …


Identifying The Microphysical Sensitivities Of Mesoscale And Synoptic Precipitation Using An Ensemble Framework, Lauriana Gaudet Jan 2021

Identifying The Microphysical Sensitivities Of Mesoscale And Synoptic Precipitation Using An Ensemble Framework, Lauriana Gaudet

Legacy Theses & Dissertations (2009 - 2024)

Through ensemble sensitivity analysis, this dissertation aims to identify the amount of forecast uncertainty that stems from the representation of mixed-phase cloud microphysics within the Weather Research and Forecasting Model (WRF). The first research thrust focuses on how the evolution of ice crystal shape and choice of ice nucleation parameterization in the Adaptive Habit Microphysics Model (AHM) influences the lake-effect storm that occurred during Intensive Operating Period 4 (IOP4) of the Ontario Winter Lake Effect Systems (OWLeS) Field Campaign. This localized snowstorm produced total liquid-equivalent precipitation amounts up to 17.92 mm during a 16-hour time period, providing a natural laboratory …


Process-Based Evaluation Of Stochastic Perturbed Parameterization Tendencies On Ensemble Forecasts Of Heavy Rainfall Events, Kevin Michael Lupo Jan 2021

Process-Based Evaluation Of Stochastic Perturbed Parameterization Tendencies On Ensemble Forecasts Of Heavy Rainfall Events, Kevin Michael Lupo

Legacy Theses & Dissertations (2009 - 2024)

Stochastic model error schemes, such as the stochastic perturbed parameterization tendencies (SPPT) and independent SPPT (iSPPT) schemes, have become an increasingly utilized method to represent model error associated with uncertain subgrid-scale processes in ensemble prediction systems (EPSs). While much of the current literature focuses on how stochastic methods influence ensemble skill, relatively less attention is given to the processes by which these schemes lead to forecast variability. In this vein, this dissertation examines the physical processes by which the application of SPPT and iSPPT to the microphysics, planetary boundary layer (PBL), and radiation parameterization schemes yields rainfall forecast variability. These …


Physical Characteristics And Microphysical Processing Of Atmospheric Aerosol In Rural And Urban New York State, Joseph Marto Jan 2021

Physical Characteristics And Microphysical Processing Of Atmospheric Aerosol In Rural And Urban New York State, Joseph Marto

Legacy Theses & Dissertations (2009 - 2024)

Atmospheric aerosol has profound impacts on air quality, though particles of differing sizes can have profoundly different characteristics which are understated when measurements are reported as a single parameter (typically number concentration or total mass). To address some of these concerns and to better understand the nature of atmospheric aerosol, continuous particle size distributions have been measured at two sites in New York State. Measurement was performed for particle diameters between 7.6nm - 20µm at Pinnacle State Park (Addison, New York; March 2017-April 2018) and Queens College (May 2018-September 2019) at a 5-minute time resolution. At Pinnacle State Park, aerosol …


Evaluating The Performance Of National Water Model Snow Simulations In The Northeastern United States Using Advanced Mesonet Observations, Patrick William Naple Jan 2021

Evaluating The Performance Of National Water Model Snow Simulations In The Northeastern United States Using Advanced Mesonet Observations, Patrick William Naple

Legacy Theses & Dissertations (2009 - 2024)

Snow is a critical component in the hydrologic cycle and critical to runoff in many regions. While not as deep or persistent as snow in the Western United States (WUS) , snow in the Northeastern US (NEUS) is critical to water resource management and flood forecasting. For hydrological applications, snow is simulated using coupled hydrology models . These models couple numerical weather models, land surface models, and channel routing models that simulate water transport. One such coupled hydrology model is the NOAA National Water Model (NWM), implemented in 2016. The NWM runs a specific configuration of the WRF-Hydro community model. …


The Role Of Ammonia In Atmospheric New Particle Formation And Implications For Cloud Condensation Nuclei, Arshad Arjunan Nair Jan 2021

The Role Of Ammonia In Atmospheric New Particle Formation And Implications For Cloud Condensation Nuclei, Arshad Arjunan Nair

Legacy Theses & Dissertations (2009 - 2024)

Atmospheric ammonia has received recent attention due to (a) its increasing trend across various regions of the globe; (b) the associated direct and indirect (through PM2.5) effects on human health, the ecosystem, and climate; and (c) recent evidence of its role in significantly enhancing atmospheric new particle formation (NPF or nucleation) rates. The mechanisms behind nucleation in the atmosphere are not fully understood, although over the last decade there have been significant developments in our understanding. This dissertation aims at improving our understanding of atmospheric ammonia in the atmosphere, its spatiotemporal variability, its role in atmospheric new particle formation, and …


The Impact Of North Pacific And North Atlantic Baroclinic Cyclones On Downstream Predictability, Adam Wayne Sisco Jan 2021

The Impact Of North Pacific And North Atlantic Baroclinic Cyclones On Downstream Predictability, Adam Wayne Sisco

Legacy Theses & Dissertations (2009 - 2024)

Baroclinic cyclogenesis can act as an impulsive disturbance along the midlatitude waveguide and promote the dispersion of Rossby waves, potentially impacting the predictability of the downstream midlatitude flow. Indeed, several studies have traced medium-range forecast errors and uncertainties to upstream cyclone development, especially when diabatic processes are involved in modifying the upper-tropospheric potential vorticity (PV) distribution. However, it remains unclear why some forecasts downstream of cyclogenesis are particularly uncertain while others are not. This study uses a 30-yr (1985–2014) sample of cool-season North Pacific and North Atlantic baroclinic cyclones and forecasts from the second-generation Global Ensemble Forecast System (GEFS) reforecast …


Land-Atmosphere-Cloud Interaction : Sensitivity Of Weather Forecast Models To Complex Land Surface Conditions In New York State, Lanxi Min Jan 2021

Land-Atmosphere-Cloud Interaction : Sensitivity Of Weather Forecast Models To Complex Land Surface Conditions In New York State, Lanxi Min

Legacy Theses & Dissertations (2009 - 2024)

The land-atmosphere coupling system is important for the simulation of key quantities like surface temperature, precipitation, and radiative energy. Over the complex terrain of New York State, the land-atmosphere coupling process is quite complex and misrepresenting the coupling processes could lead to strong biases. Evaluating the weather forecasting models is vital for enhancing understanding of physical and processes and further improving the model forecasting. A comprehensive observation network, the New York State Mesonet (NYSM) provides a great opportunity to investigate how the land atmosphere coupling process are simulated over complex terrain region. This research includes three components. In first part, …