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Probabilistic Forecasting Of Winter Mixed Precipitation Types In New York State Utilizing A Random Forest, Brian Chandler Filipiak
Probabilistic Forecasting Of Winter Mixed Precipitation Types In New York State Utilizing A Random Forest, Brian Chandler Filipiak
Legacy Theses & Dissertations (2009 - 2024)
Operational forecasters face a plethora of challenges when making a forecast; they must consider multiple data sources ranging from radar and satellites to surface and upper air observations, to numerical weather prediction output. Forecasts must be done in a limited window of time, which adds an additional layer of difficulty to the task. These challenges are exacerbated by winter mixed precipitation events where slight differences in thermodynamic profiles or changes in terrain create different precipitation types across small areas. In addition to being difficult to forecast, mixed precipitation events can have large-scale impacts on our society.
Large-Scale Flow Patterns Conducive To Central American Extreme Precipitation Events During Autumn, Alexander Kyle Mitchell
Large-Scale Flow Patterns Conducive To Central American Extreme Precipitation Events During Autumn, Alexander Kyle Mitchell
Legacy Theses & Dissertations (2009 - 2024)
Extreme precipitation events (EPEs), characterized by daily widespread heavy rainfall exceeding the 95th percentile across Central America, can have large impacts on agriculture, life, and property during the rainy season. EPEs during the Northern Hemisphere (NH) autumn, however, have been observed to be influenced by both tropical and extratropical originating phenomena such as easterly waves and cold surges, respectively. Given the limited research in this area, the novelty of this work is to apply a systematic approach for identifying and better understanding EPEs, and investigating their associated synoptic-scale variability using daily high-resolution observations and reanalysis products over Central America. An …
The Simulated Sensitivity Of The North American Monsoon At Convection-Permitting Scales, Brendan Wallace
The Simulated Sensitivity Of The North American Monsoon At Convection-Permitting Scales, Brendan Wallace
Legacy Theses & Dissertations (2009 - 2024)
The North American Monsoon (NAM) is a major contributor to annual rainfall for large portions of the North American Southwest. Much of the prior work examining the NAM using numerical models has been done at scales exceeding 20-km grid spacing. At these coarse scales, unresolved processes and poorly resolved geographic features can impact model performance. This can present a problem when simulating the NAM particularly with regard to orographic precipitation, precipitation on sub-daily timescales, and land surface-atmosphere interactions. This dissertation seeks to better understand the NAM through examination of several sets of convection-permitting regional climate model output. The primary goal …
Changes In Large-Scale Extreme Precipitation In Over Taiwan And The Northeast United States : Past And Future, Lexi Henny
Legacy Theses & Dissertations (2009 - 2024)
Large-scale extreme precipitation over (1) the mid-Atlantic and Northeast United States and (2) Taiwan is attributed to weather types such as atmospheric river (AR), TC, and extreme integrated vapor transport (IVT). Statistically significant increases in season-total EP day precipitation are seen at many GHCN stations in winter, summer, and fall in the mid-Atlantic and Northeast region, and at certain high-elevation grid points in Taiwan Mei-yu season. During the cold season of winter and spring, the U.S.-based changes come from AR-associated EP days and are associated with strengthened southwesterly winds and IVT either within EP days, in the season mean, or …
Understanding Changes In Precipitation, Wildfires, And Possible Governing Factors Over Central Equatorial Africa, Yan Jiang
Legacy Theses & Dissertations (2009 - 2024)
Tropical rainforests are global epicenters of biodiversity and modulators of climate. A long-term drying trend has occurred in the Congo Basin since the 1980s and this raises great concerns for sustaining the Congolese rainforest and local rain-fed agriculture. Motivated by documented rainfall changes and the need to improve understanding of main factors influencing precipitation variability and changes in Central Equatorial Africa (CEA), this dissertation conducts synthesized studies on 1) quantifying variations in precipitation seasonality by focusing on dry season duration, 2) estimating cascading wildfire risks associated with changes in precipitation patterns, and estimating impacts of 3) the tropical Indian Ocean …
Seasonal Differences In The Impacts Of Ipo And Amo On Temperature And Precipitation Over South America, Thomas Favata
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 …
Seasonal Variations And Long-Term Trend Of Mineral Dust And The Effects Of Dust On Cloud And Precipitations, Yanda Zhang
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 …
Dynamical Downscaling Of Near-Term Climate Variability And Change For The Main Hawaiian Islands Using Wrf, Katrina Marie Fandrich
Dynamical Downscaling Of Near-Term Climate Variability And Change For The Main Hawaiian Islands Using Wrf, Katrina Marie Fandrich
Legacy Theses & Dissertations (2009 - 2024)
As climate models continue to improve, the demand from resource managers and decision-makers for more accurate climate projections is increasing. However, natural climate variability poses a limit to the confidence in regional climate change projections, particularly for the mid-21st century. The unique geographic location of the Hawaiian Islands and its regional climate provide a challenging opportunity for climate modelers. The goal of this project is to examine both the Pacific Decadal Oscillation (PDO) and anthropogenic climate change for their impacts on near-term rainfall and temperature projections for the Hawaiian Islands. Of primary interest are the questions 1) is there a …
Convection-Permitting Ensemble Forecasts Of The 10-12 December 2013 Lake-Effect Snow Event: : Sensitivity To Microphysical, Planetary Boundary Layer, And Surface Layer Parameterizations, William Massey Bartolini
Convection-Permitting Ensemble Forecasts Of The 10-12 December 2013 Lake-Effect Snow Event: : Sensitivity To Microphysical, Planetary Boundary Layer, And Surface Layer Parameterizations, William Massey Bartolini
Legacy Theses & Dissertations (2009 - 2024)
Lake-effect snow (LeS) presents a substantial forecast challenge for convection-permitting models, due in part to uncertainties in the parameterization of microphysical (MP) and planetary boundary layer / surface layer (PBL/SL) processes. Here we focus on understanding these uncertainties for a LeS event that occurred during 10–12 December 2013 during the Ontario Winter Lake-effect Systems (OWLeS) field campaign. Throughout this event, long-lake-axis-parallel snowbands persisted downwind of the eastern shore of Lake Ontario, leading to snowfall accumulations as high as 105 cm (liquid precipitation equivalent of 64.5 mm) on the Tug Hill Plateau.
Precipitation Characteristics And Their Dependence On Data Resolution And Model Physics, Di Chen
Precipitation Characteristics And Their Dependence On Data Resolution And Model Physics, Di Chen
Legacy Theses & Dissertations (2009 - 2024)
To fully characterize precipitation, one often needs not only the accumulative amount (A), but also its frequency (F), intensity (I) and duration (D). These characteristics have large impacts on Earth’s hydrologic cycle. Aiming for a comprehensive understanding, this dissertation investigates precipitation characteristics and their dependence on data resolution and model physics using observational datasets and comprehensive global climate models (GCMs).
An Examination Of North Pacific Jet Regimes Conducive To Landfalling Atmospheric Rivers Along The West Coast Of North America, Eli Jacob Turasky
An Examination Of North Pacific Jet Regimes Conducive To Landfalling Atmospheric Rivers Along The West Coast Of North America, Eli Jacob Turasky
Legacy Theses & Dissertations (2009 - 2024)
Every year, the west coast of North America experiences significant economic damage and societal disruption due to the extreme precipitation associated with landfalling atmospheric rivers (ARs). ARs not only may produce significant economic and societal impacts, but also may contribute disproportionately to precipitation anomaly statistics along the west coast of the North America. The purpose of this study is to investigate: 1) the average state and evolution of the NPJ prior to AR landfall for selected categories of landfalling ARs; and 2) the dynamical processes applicable to the aforementioned categories of landfalling ARs that are linked to NPJ variability in …
The Simulated Impact Of Snow Cover And Soil Moisture On Convective Precipitation Within The Rocky Mountains Under Climate Warming, Brendan Charles Wallace
The Simulated Impact Of Snow Cover And Soil Moisture On Convective Precipitation Within The Rocky Mountains Under Climate Warming, Brendan Charles Wallace
Legacy Theses & Dissertations (2009 - 2024)
Warm season moist diurnal convection can be particularly sensitive to changes in land surface
Changes In Extreme Precipitation In The Northeast United States : 1979-2014, Macy Howarth
Changes In Extreme Precipitation In The Northeast United States : 1979-2014, Macy Howarth
Legacy Theses & Dissertations (2009 - 2024)
Extreme precipitation can have significant adverse impacts on infrastructure and property, human health, and local economies. This thesis examines recent changes in extreme precipitation in the Northeast United States, which here includes the states of Maine, New Hampshire, Vermont, New York, Massachusetts, Connecticut, Rhode Island, Pennsylvania, and New Jersey. Daily station data from 58 stations missing less than 5% of days for the years 1979–2014 from the United States Historical Climatology Network was used to analyze both total and extreme precipitation, with the latter defined as the top 1% of days with precipitation.
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 …
Climate Change On The Quelccaya Ice Cap, Central Andes, And Its Relationship With The Large-Scale Circulation, Christian Pedro Yarleque Galvez
Climate Change On The Quelccaya Ice Cap, Central Andes, And Its Relationship With The Large-Scale Circulation, Christian Pedro Yarleque Galvez
Legacy Theses & Dissertations (2009 - 2024)
Glaciated areas over the central Andes are highly sensitive to atmospheric forcings, as demonstrated by their current accelerated retreat in response to global warming. The present Thesis is focused on quantifying and assessing future climate change impacts over Quelccaya ice cap (QIC), the world-largest tropical ice body, which is considered as a representative case of the tropical Andean cryosphere. I focused my study on characterizing large-scale forcing and future changes of precipitation and temperature, since they represent the most important variables for accumulation and ablation processes in glaciated mountain regions. In my research I developed tools to overcome the lack …
Chilean Coastal Orographic Precipitation Experiment : A Tale Of Two Rain Regimes, Adam Massmann
Chilean Coastal Orographic Precipitation Experiment : A Tale Of Two Rain Regimes, Adam Massmann
Legacy Theses & Dissertations (2009 - 2024)
The Chilean Coastal Orographic Precipitation Experiment Pilot Project (CCOPE-2015) was an exploratory field campaign to better understand the mechanisms of orographic precipitation enhancement in the Nahuelbuta Mountains of Southern Chile (38 deg. S.). Observations collected include: (1) surface rainfall from a network of 10 data logging rain gauges, (2) vertical precipitation profiles from a pair of K-band Micro Rain Radars, (3) rain drop size distributions from an optical disdrometer, (4) upstream wind and thermodynamic profiles from radiosonde launches, and (5) aerosol number concentration and size distribution measurements from a condensation particle counter and an ultra-high sensitivity aerosol spectrometer.
Hydroclimate Changes In The South-Central Great Plains Of The United States : A Synoptic Approach, Pawel Slaski
Hydroclimate Changes In The South-Central Great Plains Of The United States : A Synoptic Approach, Pawel Slaski
Legacy Theses & Dissertations (2009 - 2024)
Hydroclimate changes over the Southern Central Great Plains (SCGP) of the United States have been occurring throughout the last century. These changes have had a major impact on the local ecosystems, agriculture, and human society in the region by, e.g., producing a higher frequency of drought over the last century. Climate models project further increases of drought in the 21st century over this region under increasing greenhouse gases. This study analyzes climate model simulations to examine changes in synoptic conditions associated with the projected drought increases over the SCGP. Synoptically, mesoscale convective complexes (MCCs) produce a large portion of the …