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2021

Boundary layer (Meteorology)

Articles 1 - 6 of 6

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

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 …


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 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 …


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 …


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, …