Meteorology Commons^™

Seasonal Variability And Predictability Of Monsoon Precipitation In Southern Africa, Matthew F. Horan, Fred Kucharski, Moetasim Ashfaq

Faculty Publications

Rainfed agriculture is the mainstay of economies across Southern Africa (SA), where most precipitation is received during the austral summer monsoon. This study aims to further our understanding of monsoon precipitation predictability over SA. We use three natural climate forcings, El Niño–Southern Oscillation, Indian Ocean Dipole (IOD), and the Indian Ocean Precipitation Dipole (IOPD)—the dominant precipitation variability mode—to construct an empirical model that exhibits significant skill over SA during monsoon in explaining precipitation variability and in forecasting it with a five-month lead. While most explained precipitation variance (50%–75%) comes from contemporaneous IOD and IOPD, preconditioning all three forcings is key …

Using Phenology To Unravel Differential Soil Water Use And Productivity In A Semiarid Savanna, Blake Steiner, Russell L. Scott, Jia Hu, Natasha Mcbean, Andrew Richardson, David J. P. Moore

University Administration Publications

Savannas are water-limited ecosystems characterized by two dominant plant types: trees and an understory primarily made up grass. Different phenology and root structures of these plant types complicate how savanna primary productivity responds to changes in water availability. We tested the hypothesis that productivity in savannas is controlled by the temporal and vertical distribution of soil water content (SWC) and differences in growing season length of understory and tree plant functional types. To quantify the relationship between tree, understory, and savanna-wide phenology and productivity, we used PhenoCam and satellite observations surrounding an eddy covariance tower at a semiarid savanna site …

Atmospheric Impacts From The 2010 Deepwater Horizon Oil Spill, Charles Philip Johnson

LSU Master's Theses

Although the ecological devastations induced by an oil spill are well studied, the hydrometeorological impacts from a long-term slick have gone unnoticed. The ocean-surface alterations stemming from the lasting oil footprint increase solar radiation absorption which in turn alters the surface pressure and moisture gradients and wind speeds thereby influencing precipitation surrounding the oil spill. Revealing the potential impacts from these could better aid in the safety of crews cleaning spills and provide a better understanding of how humans alter the landscape. This thesis examines the changes in local hydrometeorology brought on by the 2010 summer Deepwater Horizon (DWH) oil …

Storm In A Glass Lesson Plan, Admin Stem For Success

STEM for Success Showcase

Lesson Plan and Video Demonstration for the "Storm in a Glass" Activity, which teaches students about precipitation.

Precipitation Recorded In The Turkana Basin From 2005 To 2022., Acacia Leakey, Greg Henkes, Mae Saslaw, Dino Martins

Geosciences Research Data

This is a dataset of precipitation recorded at three sites in northern Kenya near Lake Turkana using standard rain gauges. The data was recorded at the Koobi Fora Research Station (3.947736, 36.186166) from March 2003 until 2006, at the Turkana Basin Institute’s Ileret facility (4.28510, 36.262158) from 2006 to 2022 and at the Turkana Basin Institute’s Turkwel facility (3.140825, 35.864599) from 2012 to 2022. The data was collected manually by TBI staff observing gradation lines on the collectors following rainfall events and recorded as a single total for each 24 hour period.

Climatology Of Rainfall Distribution And Asymmetries Of Tropical Cyclones: A Global Perspective, Oscar Guzman Rey

FIU Electronic Theses and Dissertations

Estimating the magnitude of tropical cyclone (TC) rainfall at different landfalling states is an important aspect of the TC forecast that directly affects the level of response from emergency managers in coastal areas. This research analyses the spatial distribution of the rainfall magnitude in tropical cyclones (TCs) at different stages over global oceans. The research’s central hypothesis is that TC rainfall exhibits distinct features in the long-term satellite dataset due to the evolution of the spatial distribution, radial variation, and asymmetries at the stages before, during, and after landfall. The resulting patterns are analyzed through a statistical approach that takes …

Understanding Coastal And Inland Hydrometeorological Hazards Produced By Extratropical And Tropical Cyclones Along The East Coast Of The United States, Katherine Towey

Dissertations, Theses, and Capstone Projects

As global temperatures continue to rise, the effects of anthropogenic climate change will impact the magnitude and frequency of pluvial, fluvial, and coastal flooding events. If we want to accurately predict changes in these flooding events, we need to fully understand them in the current climate. As such, this research examines the relationship between hydrometeorological hazards and the characteristics of the storm types, such as extratropical cyclones (ETCs) and tropical cyclones (TCs), that produce such hazards. Through the use of observational and reanalysis data, the work herein utilizes a cyclone-hazard association algorithm and extreme value analysis to assess the extent, …

Small-Scale Variability In Warm Season, Precipitation Around An Urban Area: A Case Study Of Louisville-Jefferson County, Ky., Isaiah I. Kingsberry

Electronic Theses and Dissertations

Numerous studies have detected anomalous precipitation patterns occurring up to 50 km downwind of major cities, providing major evidence that cities inadvertently modify precipitation and atmospheric circulations. Louisville is one such major city with a growing body of evidence of inadvertent precipitation modification. Despite these efforts, the physical mechanisms driving small-scale and unintentional changes in urban precipitation are little understood, being rooted largely in theory rather than in physical observations. This study seeks to build upon previous research by analyzing ground-based precipitation observations recorded by a high-density gauge network located within approximately 40 km of Louisville’s urban center. The results …

Atlantic Ocean Variability And European Alps Winter Precipitation, Giuseppe Formetta, Jonghun Kam, Sahar Sadeghi, Glenn Tootle, Thomas Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Winter precipitation (snowpack) in the European Alps provides a critical source of freshwater to major river basins such as the Danube, Rhine, and Po. Previous research identified Atlantic Ocean variability and hydrologic responses in the European Alps. The research presented here evaluates Atlantic Sea Surface Temperatures (SSTs) and European Alps winter precipitation variability using Singular Value Decomposition. Regions in the north and mid-Atlantic from the SSTs were identified as being tele-connected with winter precipitation in the European Alps. Indices were generated for these Atlantic SST regions to use in prediction of precipitation. Regression and non-parametric models were developed using the …

The Effect Of Barometric Pressure, Temperature, And Precipitation On Preterm Labor In Expecting Women In South Carolina, Allison K. Fletcher

Journal of the South Carolina Academy of Science

Each year, approximately 9.9% of infants in the United States are born prematurely at less than 37 weeks of gestation with unidentified causes. From 2014 to 2016, the total preterm birth rate rose 3%, and late preterm birth rates rose almost 4%. One source of preterm labor that has been examined in recent years is its potential correlation with meteorological phenomena, including barometric pressure, temperature, and precipitation. In September of 2019, birth data recording 322 deliveries from two South Carolina hospitals was collected along with weather data on the given dates. The changes in temperature, barometric pressure, and precipitation for …

A Pilot Experiment To Replace Missing Rainfall Events Using Soil Moisture Information From The Kansas Mesonet, N. Parker, A. Patrignani

Kansas Agricultural Experiment Station Research Reports

The Kansas Mesonet is a state-of-the-art environmental monitoring network that provides accurate rainfall measurements across Kansas. However, missing rainfall records are common problems in weather stations that rely on tipping bucket rain gauges. In this study, we conducted a pilot experiment to estimate missing rainfall records from root-zone soil moisture information recorded at Kansas Mesonet stations. Soil moisture is recorded at depths of 5, 10, 20, and 50 cm using the Campbell Scien­tific CS655 soil water reflectometer. Hourly rainfall and soil moisture data from mid- August 2017 to mid-May 2018 were taken from three stations (Lakin, Manhattan, and Hays) of …

Application Of A Hybrid Statistical–Dynamical System To Seasonal Prediction Of North American Temperature And Precipitation, Sarah Strazzo, Dan C. Collins, Andrew Schepen, Q. J. Wang, Emily Becker, Liweli Jia

Publications

Recent research demonstrates that dynamical models sometimes fail to represent observed teleconnection patterns associated with predictable modes of climate variability. As a result, model forecast skill may be reduced. We address this gap in skill through the application of a Bayesian postprocessing technique—the calibration, bridging, and merging (CBaM) method—which previously has been shown to improve probabilistic seasonal forecast skill over Australia. Calibration models developed from dynamical model reforecasts and observations are employed to statistically correct dynamical model forecasts. Bridging models use dynamical model forecasts of relevant climate modes (e.g., ENSO) as predictors of remote temperature and precipitation. Bridging and calibration …

Madden-Julian Oscillation Relationships With Cool Season Cyclogenesis, Daily Precipitation, And Cool Season Severe Weather Frequencies In The Gulf Of Mexico Region, Stephen Paul Caparotta

LSU Doctoral Dissertations

Tropical cyclone variability in the Gulf of Mexico (GoM) has been the focus of a considerable amount of research. Variability on both interannual scales, related to the El Niño-Southern Oscillation (ENSO), and on subseasonal scales, related to the Madden-Julian Oscillation (MJO), is well documented. By contrast, very little research exists on the relationships between the MJO and cool season, non-tropical cyclones in the GoM.

The MJO influence on cool season (October-March) cyclogenesis in the GoM variability is explored here. Additionally, daily precipitation variability and cool season severe weather variability is examined for areas near and just inland of the GoM. …

Synoptic Typing Of Extreme Cool-Season Precipitation Events At St. John's, Newfoundland, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

Quantitative precipitation forecasting (QPF) continues to be a significant challenge in operational forecasting, particularly in regions susceptible to extreme precipitation events. St. John’s, Newfoundland, Canada (CYYT), is affected frequently by such events, particularly in the cool season (October–April).

The 50 median events in the extreme (>33.78 mm during a 48-h period) precipitation event category are selected for further analysis. A manual synoptic typing is performed on these 50 events, using two separate methodologies to partition events. The first method utilizes a Lagrangian backward air parcel trajectory analysis and the second method utilizes the evolution of dynamically relevant variables, including …

Synoptic-Scale Characteristics And Precursors Of Cool-Season Precipitation Events At St. John's, Newfoundland, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

The issue of quantitative precipitation forecasting continues to be a significant challenge in operational forecasting, particularly in regions susceptible to frequent and extreme precipitation events. St. John’s, Newfoundland, Canada, is one location affected frequently by such events, particularly in the cool season (October–April). These events can include flooding rains, paralyzing snowfall, and damaging winds.

A precipitation climatology is developed at St. John’s for 1979–2005, based on discrete precipitation events occurring over a time period of up to 48 h. Threshold amounts for three categories of precipitation events (extreme, moderate, and light) are statistically derived and utilized to categorize such events. …

Synoptic Typing And Precursors Of Heavy Warm-Season Precipitation Events At Montreal, Québec, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum, Giselle Dookhie

Shawn M. Milrad

A precipitation climatology is compiled for warm-season events at Montreal, Québec, Canada, using 6-h precipitation data. A total of 1663 events are recorded and partitioned into three intensity categories (heavy, moderate, and light), based on percentile ranges. Heavy (top 10%) precipitation events (n = 166) are partitioned into four types, using a unique manual synoptic typing based on the divergence of Q-vector components. Type A is related to cyclones and strong synoptic-scale quasigeostrophic (QG) forcing for ascent, with high-θe air being advected into the Montreal region from the south. Types B and C are dominated by frontogenesis (mesoscale QG forcing …

Precipitation Modulation By The Saint Lawrence River Valley In Association With Transitioning Tropical Cyclones, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

The St. Lawrence River valley (SLRV) is an important orographic feature in eastern Canada that can affect surface wind patterns and contribute to locally higher amounts of precipitation. The impact of the SLRV on precipitation distributions associated with transitioning, or transitioned, tropical cyclones that approached the region is assessed. Such cases can result in heavy precipitation during the warm season, as during the transition of Hurricane Ike (2008). Thirty-eight tropical cyclones tracked within 500 km of the SLRV from 1979 to 2011. Utilizing the National Centers for Environmental Prediction (NCEP) North American Regional Reanalysis (NARR), 19 of the 38 cases …

A Diagnostic Examination Of Consecutive Extreme Cool-Season Precipitation Events At St. John's, Newfoundland, In December 2008, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

St. John’s, Newfoundland, Canada (CYYT), is frequently affected by extreme precipitation events, particularly in the cool season (October–April). Previous work classified precipitation events at CYYT into categories by precipitation amount and a manual synoptic typing was performed on the 50 median extreme precipitation events, using two separate methods. Here, consecutive extreme precipitation events in December 2008 are analyzed. These events occurred over a 6-day period and produced over 125 mm of precipitation at CYYT. The first manual typing method, using a backward-trajectory analysis, results in both events being classified as “southwest,” which were previously defined as the majority of the …

A Meteorological Analysis Of The 2013 Alberta Flood: Antecendent Large-Scale Flow Pattern And Synoptic-Dynamic Characteristics, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah

Shawn M. Milrad

The 19–21 June 2013 Alberta flood was the costliest (CAD $6 billion) natural disaster in Canadian history. The flood was caused by a combination of above-normal spring snowmelt in the Canadian Rockies, large antecedent precipitation, and an extreme rainfall event on 19–21 June that produced rainfall totals of 76 mm in Calgary and 91 mm in the foothills. As is typical of flash floods along the Front Range of the Rocky Mountains, rapidly rising streamflow proceeded to move downhill (eastward) into Calgary.

A meteorological analysis traces an antecedent Rossby wave train across the North Pacific Ocean, starting with intense baroclinic …

Dynamical And Precipitation Structures Of Poleward-Moving Tropical Cyclones In Eastern Canada, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

Tropical cyclones in the western North Atlantic basin are a persistent threat to human interests along the east coast of North America. Occurring mainly during the late summer and early autumn, these storms often cause strong winds and extreme rainfall and can have a large impact on the weather of eastern Canada. From 1979 to 2005, 40 named (by the National Hurricane Center) tropical cyclones tracked over eastern Canada. Based on the time tendency of the low-level (850–700 hPa) vorticity, the storms are partitioned into two groups: ‘‘intensifying’’ and ‘‘decaying.’’ The 16 intensifying and 12 decaying cases are then analyzed …

Spatio-Temporal Variability Of Precipitation And Drought In The State Of Arizona, Usa, Samuel Nimako Nyarkoh

Masters Theses

As a result of climate change, several dry regions continue to get drier as precipitation amounts decline. This decline impact water resources and hinder economic development. Understanding the variability of precipitation and drought through climatic, agricultural and hydrological studies is therefore critical to decision makers and stakeholders in developing proactive measures that promotes economic development.

This study therefore uses dataset from 55 Meteorological stations containing 110-year (1900-2010) monthly precipitation data and a series of spatial and temporal tests to investigate the spatial and temporal patterns of precipitation and drought as well as the effects of local factors such as topography …

Air Pressure, Clouds, And Weather, Laura Shofield

Science and Engineering Saturday Seminars

1) What are basis characteristics of the atmosphere?

2) What is the horizontal and vertical movement of air in a “High” and “Low?”

3) How do clouds form and what can they tell us?

4) How are temperature, pressure and clouds related?

5) Applying concepts to real-time data

Ensemble Variability In Rainfall Forecasts Of Hurricane Irene (2011), Molly Becker Smith

Legacy Theses & Dissertations (2009 - 2024)

As tropical cyclones (TCs) move into the midlatitudes, they are often associated with extensive heavy precipitation. This precipitation can lead to widespread flooding events, such as occurred with Hurricane Irene (2011) over the northeastern United States. Despite the high-impact nature of these events, there are relatively few studies that explore the sensitivity of precipitation forecasts to model initial conditions, beyond focusing on the variability in forecast TC track.

Analyzing Accuracy Of The Lufft Ws600 In Remotely Measuring Precipitation Events, Justin Gay

STAR Program Research Presentations

The goal of this project was to analyze the accuracy of the Lufft WS600 Weather Sensor in measuring the rate of both liquid and solid precipitation. Measurement accuracy, especially in remote locations, can be difficult to obtain and quantify. Wind, blowing debris, and atmospheric particles can all have the capacity to interfere with instruments that are not being continuously compared to manual observations. Access to quality precipitation data sets are important for both hydrologic and weather forecasting, climate monitoring, and understanding the role of water cycling through ecosystems. Commercially, weather sensors are heavily relied upon by the Federal Aviation Administration …

New Metric For Defining The Time Of Extratropical Transition Of Tropical Cyclones, Ajay Raghavendra, Shawn M. Milrad

Publications

Almost half of all tropical cyclones (TCs) in the Atlantic basin undergo extratropical transition (ET). During an ET event, wind fields often expand dramatically, resulting in more widely-felt impacts. Moreover, the heaviest precipitation typically shifts to the left-of-center (LOC), which can result in inland flash flooding hundreds of kilometers from the cyclone center. While several objective metrics to track and predict ET have been developed, they rely at least partially on internal tropical cyclone structure, for which numerical models show less skill. Further, these metrics fail to account for static stability, which plays a vital role in determining precipitation amounts. …

Analysis Of The Precipitation Detection Algorithm For The Geonor T-200b Precipitation Gauge To Improve Accuracy, Megan Lerman, Robert K. Goodrich

STAR Program Research Presentations

In an effort to improve the precipitation detection algorithm for the Geonor All Weather Precipitation Gauge, an automated truth algorithm has been created to detect errors in the original algorithm. The original algorithm detects precipitation in real time and uses the rate of precipitation to indicate an event. The automated truth does not detect in real time, and focuses on precipitation accumulation to indicate an event. Since the automated truth is delayed, it is able to consider the data collected before and after the point it is analyzing. The automated truth is already more accurate than the original algorithm but …

Precipitation Data, M. Knapp

Kansas Agricultural Experiment Station Research Reports

Precipitation data for agricultural experiment stations in Kansas, 2014-2015.

A Meteorological Analysis Of The 2013 Alberta Flood: Antecendent Large-Scale Flow Pattern And Synoptic-Dynamic Characteristics, Shawn M. Milrad, John R. Gyakum, Eyad H. Atallah

Publications

The 19–21 June 2013 Alberta flood was the costliest (CAD $6 billion) natural disaster in Canadian history. The flood was caused by a combination of above-normal spring snowmelt in the Canadian Rockies, large antecedent precipitation, and an extreme rainfall event on 19–21 June that produced rainfall totals of 76 mm in Calgary and 91 mm in the foothills. As is typical of flash floods along the Front Range of the Rocky Mountains, rapidly rising streamflow proceeded to move downhill (eastward) into Calgary.

A meteorological analysis traces an antecedent Rossby wave train across the North Pacific Ocean, starting with intense baroclinic …

Springtime Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Gcm Experiments: Northern Hemisphere Circulation And North American Precipitation, Michael C. Veres

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

In this study, a series of experiments using idealized sea surface temperatures (SST), land and orography are performed to examine the interactions between the Atlantic Multidecadal Oscillation (AMO), continents and major orography. Three sets of experiments are done using an increasingly realistic surface boundary (aqua-planet, land without orography and land with orography) and run using perpetual equinox conditions. For each land surface boundary, the model is forced with a zonally symmetric SST, with additional experiments with an imposed positive or negative SST anomalies in the North Atlantic. The experiments are then compared to determine how these forcings interact and what …

Synoptic Typing And Precursors Of Heavy Warm-Season Precipitation Events At Montreal, Québec, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum, Giselle Dookhie

Publications

A precipitation climatology is compiled for warm-season events at Montreal, Québec, Canada, using 6-h precipitation data. A total of 1663 events are recorded and partitioned into three intensity categories (heavy, moderate, and light), based on percentile ranges. Heavy (top 10%) precipitation events (n = 166) are partitioned into four types, using a unique manual synoptic typing based on the divergence of Q-vector components. Type A is related to cyclones and strong synoptic-scale quasigeostrophic (QG) forcing for ascent, with high-θe air being advected into the Montreal region from the south. Types B and C are dominated by frontogenesis (mesoscale QG forcing …