Oceanography and Atmospheric Sciences and Meteorology Commons^™

Understanding The Food Water Nexus: Characterizing The Impact Of Climatological Anomalies On Agrosystems, Patrick M. Wurster Jr.

Graduate Student Theses, Dissertations, & Professional Papers

Climate variability at global and regional scales is escalating with increased atmospheric carbon and is expected to magnify the intensity and duration of meteorological extremes, especially droughts. From the many environmental stresses that diminish crop production (e.g., soil salinity, frost, soil erosion) drought is one of the most prevalent. This study focuses on the sensitivity of three key crops produced in the northwestern United States to climatological anomalies, while controlling for attribution using anomalies in price. The study differs from similar studies in that we focus on variability in production which captures both yield (tonnes/ha) and cropping area (ha), as …

Combined Assimilation Of Satellite Precipitation And Soil Moisture: A Case Study Using Trmm And Smos Data, Liao-Fan Lin, Ardeshir M. Ebtehaj, Alejandro N. Flores, Satish Bastola, Rafael L. Bras

Geosciences Faculty Publications and Presentations

This paper presents a framework that enables simultaneous assimilation of satellite precipitation and soil moisture observations into the coupled Weather Research and Forecasting (WRF) and Noah land surface model through variational approaches. The authors tested the framework by assimilating precipitation data from the Tropical Rainfall Measuring Mission (TRMM) and soil moisture data from the Soil Moisture Ocean Salinity (SMOS) satellite. The results show that assimilation of both TRMM and SMOS data can effectively improve the forecast skills of precipitation, top 10-cm soil moisture, and 2-m temperature and specific humidity. Within a 2-day time window, impacts of precipitation data assimilation on …

Land Use Land Cover Change Effects On Southern Great Plains Precipitation, Alexandra Caruthers

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

Great Plains land use has changed substantially over the last 160 years, altering the properties of the land through increased settlement and advances in irrigation. Changing the interface between the land and atmosphere has implications for the atmospheric boundary layer, the regional circulation, the local surface energy budget and resulting precipitation patterns. Land use land cover (LULC) changes are an important topic for this region due to its heavy dependence on agriculture. This study investigates differences in Southern Great Plains precipitation patterns between four LULC scenarios: the pre-settlement, 1920’s, Dust Bowl and present day eras. Using the Weather Research and …

How Accurate Are Satellite Estimates Of Precipitation Over The North Indian Ocean?, Satya Prakash, M. R. Ramesh Kumar, Simi Mathew, R. Venkatesan

Publications and Research

Following the launch of the Global Precipitation Measurement (GPM) Core Observatory in early 2014, motivated from the successful Tropical Rainfall Measurement Mission (TRMM) satellite, an advanced and sophisticated global multi-satellite precipitation product – Integrated Multi- satellitE Retrievals for GPM (IMERG) was released at finer spatio-temporal scales. This precipitation product has been upgraded recently after several refinements and supposed to be superior to other existing global or quasi-global multi-satellite precipitation estimates. In the present study, IMERG precipitation is comprehensively evaluated for the first time against moored buoy observations over the north Indian Ocean at hourly scale for the study period of …

Environmental Factors Affecting Loggerhead Sea Turtle (Caretta Caretta) Nesting, Hatching, And Incubation Patterns In Broward County, Florida, Zoey Ellen Best

HCNSO Student Theses and Dissertations

Reproductive success in loggerhead (Caretta caretta) sea turtles is strongly dependent on the effective placement and internal conditions of their nests. Embryos rely on optimal incubation conditions for proper development and growth, which determines how many hatchlings will emerge from the nest. The internal microclimate of each nest is delicately balanced and can be easily influenced by external environmental conditions. This study was designed to examine several environmental variables and determine their effects on sea turtle nesting numbers, hatching success, and incubation conditions in Broward County Florida. Over a span of 25 years (1991-2015), the Broward County Sea …

Effects Of Climate Oscillations On Wildland Fire Potential In The Continental United States, Shelby A. Mason, Peter E. Hamlington, Benjamin D. Hamlington, W. Matt Jolly, Chad M. Hoffman

OES Faculty Publications

The effects of climate oscillations on spatial and temporal variations in wildland fire potential in the continental U.S. are examined from 1979 to 2015 using cyclostationary empirical orthogonal functions (CSEOFs). The CSEOF analysis isolates effects associated with the modulated annual cycle and the El Nino-Southern Oscillation (ENSO). The results show that, in early summer, wildland fire potential is reduced in the southwest during El Nino but is increased in the northwest, with opposite trends for La Nina. In late summer, El Nino is associated with increased wildland fire potential in the southwest. Relative to the mean, the largest impacts of …

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.

Climate Fingerprints Of The Interdecadal Pacific Oscillation, Bo Dong

Legacy Theses & Dissertations (2009 - 2024)

The Interdecadal Pacific Oscillation (IPO) is a multi-decadal quasi-oscillation seen primarily in tropical and extratropical Pacific sea surface temperatures (SSTs). Interacting with the atmosphere, the IPO has been shown to affect global and regional climate. However, a quantitative global synthesis of the IPO’s climate fingerprints and the underlying mechanisms are still lacking. Based on observational and reanalysis data and atmospheric model simulations, this dissertation investigates the IPO’s influence on regional climates over the globe, and its interactions with El Niño-Southern Oscillation (ENSO) and global warming.

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 …

Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu

Graduate Theses and Dissertations

Although climate change impacts vary geographically and temporally, studies at local levels are not readily available for stakeholders to better understand how their local communities would be affected and what remedial measures could be more effective in their local contexts. This dissertation has examined climate change and its impacts in two different local contexts: eastern Arkansas in the USA and Nyando in Kenya. The first part of this dissertation develops agro-meteorological indicators and examines the relationship between agro-meteorological indicators and crop yields in eastern Arkansas between 1960 and 2014. Results reveal that temperature based indicators were more strongly correlated to …

Slides: Water Allocation And Water Markets In Spain, Nuria Hernández-Mora

Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)

Presenter: Nuria Hernández Mora, Universidad de Sevilla, Spain

22 slides

Differing Roles Of The Great Plains Low-Level Jet In Producing Warm Season Precipitation Over The Central United States In 2002, Mengyuan Shang

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

The purpose of this research is to describe and compare different roles of the Great Plains low-level jet (GPLLJ) in producing warm season precipitation over the central United States by model simulation. After going through 35 years’ (from 1979- 2013) NCEP North American Regional Reanalysis (NARR) data, year 2002 was selected for model simulation as it contained a “wet period” (May- June) and a “dry period” (July- August). The model simulation was done by using Weather Research and Forecasting (WRF) Regional Model. In this study, the GPLLJ was defined by the low-level wind at 925 hPa. The results showed the …

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. …

Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier

Dartmouth Scholarship

Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. However, the quantitative link between precipitation and sea ice extent is poorly constrained. Here we present observational evidence for the response of precipitation to sea ice reduction and assess the sensitivity of the response. Changes in the proportion of moisture sourced from the Arctic with sea ice change in the Canadian Arctic and Greenland Sea regions over the past two decades are inferred from annually averaged deuterium excess (d-excess) measurements from six sites. Other influences on …

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 …

An Assessment Of Long-Term Changes In The Characterisitcs Of Precipitation In The Upper Midwest, Blake Steven Lea

Graduate Theses/Dissertations

As climate change progresses, many forecasts for the upper Midwest predict increases in annual precipitation, but with a shift in seasonal patterns that will leave the summer months drier with less frequent, higher magnitude storm events. Changes in precipitation patterns have the potential to alter the sediment budget and discharge patterns in watersheds. The purpose of this study was to determine the effects changes in frequency, magnitude, duration, and intensity of precipitation might have on streamflow and sediment budgets in the upper Midwest. This analysis was carried out using hourly precipitation data from 1948 to 2013 from 23 sites and …

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 …

Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group

Books, Reports, and Studies

40 pages (includes color illustrations).

El Nino Southern Oscillation (Enso) Enhances Co2 Exchange Rates In Freshwater Marsh Ecosystems In The Florida Everglades, Sparkle L. Malone, Christina L. Staudhammer, Steven F. Oberbauer, Paulo Olivas, Michael G. Ryan, Jessica L. Schedlbauer, Henry W. Loescher, Gregory Starr

Biology Faculty Publications

No abstract provided.

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 …

The Effects Of Downsloping On Storm Precipitation Distributions In The Capital District Of New York State, Kyle James Pallozzi

Atmospheric & Environmental Sciences

Downsloping is a process which has an impact on many precipitation events in the Capital District of New York State. This study examines the effect of 850 hPa and 925 hPa mean vector wind direction, as well as the individual 850 hPa and 925 hPa wind directions observed through soundings, during precipitation events on precipitation distributions in the Capital District of New York State. Results from this study suggests that 850 hPa and 925 hPa mean vector wind as well as the 850 hPa and 925 hPa wind favor downsloping off of the Greens and Taconics, and therefore lower precipitation …

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 …

Influence Of Regional Precipitation Patterns On Stable Isotopes In Ice Cores From The Central Himalayas, H. Pang, S. Hou, Susan Kaspari, P. A. Mayewski

All Faculty Scholarship for the College of the Sciences

Several ice cores have been recovered from the Dasuopu (DSP) Glacier and the East Rongbuk (ER) Glacier in the central Himalayas since the 1990s. Although the distance between the DSP and the ER ice core drilling sites is only 125 km, the stable isotopic record (18O or D) of the DSP core is interpreted in previous studies as a temperature proxy, while the ER core is interpreted as a precipitation proxy. Thus, the climatological significance of the stable isotopic records of these Himalayan ice cores remains a subject of debate. Based on analysis of regional precipitation patterns over the region, …

Significant Impacts Of Radiation Physics In The Wrf Model On The Precipitation And Dynamics Of The West African Monsoon, R. Li, J. Jin, Shih-Yu (Simon) Wang, R. R. Gillies

Plants, Soils, and Climate Faculty Publications

Precipitation from the West African Monsoon (WAM) provides food security and supports the economy in the region. As a consequence of the intrinsic complexities of the WAM’s evolution, accurate simulations of the WAM and its precipitation regime, through the application of regional climate models, are challenging. We used the coupled Weather Research and Forecasting (WRF) and Community Land Model (CLM) to explore impacts of radiation physics on the precipitation and dynamics of the WAM. Our results indicate that the radiation physics schemes not only produce biases in radiation fluxes impacting radiative forcing, but more importantly, result in large bias in …

Holocene Paleoenvironmental Reconstruction From Mexico's Pacific Coast-A Paleotempestological Investigation, Thomas Bianchette

LSU Doctoral Dissertations

This dissertation examines the paleoenvironments of four lagoons from Mexico’s Pacific coast, with the aim of retrieving sediment deposition from storm surge events to determine long-term tropical cyclone (TC) records. Lagoons Agua Dulce, Boquita, Mitla, and Nuxco are located along a 700 km stretch in states Jalisco and Guerrero. Roughly 70 meters of sediment were collected and subjected to multiple proxies, including loss-on ignition, a microfossil survey, and geochemical analysis. Nuxco’s dynamism is caused by intense and prolonged rainfall (largely from TCs), responsible for increasing water level, opening the tidal inlet, and draining the site (termed “blowouts”). High amounts of …

Impacts Of Climate Changes On The Spatiotemporal Distribution Of Precipitation In The Western United States, Peng Jiang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Precipitation in the Intermountain West is characterized by its great variability in both spatial and temporal distributions. Moreover, the spatiotemporal distribution of the precipitation is changing due to the climate changes. In this dissertation, three studies are conducted to investigate the multi-scale temporal variability of precipitation, the performance of current climate models on this variability, the influence of large-scale ocean oscillations on heavy precipitation, and the impact of human induced global warming on storm properties.

The first study is to examine the performance of current climate models on the simulation of the multi-scale temporal variability determined from the observed station …

Slides: Is There A Dust Bowl In Our Future?: Projections For The Eastern Rockies And Central Great Plains, Dennis Ojima

Water, Climate and Uncertainty: Implications for Western Water Law, Policy, and Management (Summer Conference, June 11-13)

Presenter: Dennis Ojima, Senior Research Scientist, Natural Resource Ecology Laboratory, Colorado State University (NREL/CSU)

30 slides

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

Publications

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 …

The Influence Of The Tibetan Plateau Elevation On The Global And Asian Monsoons, Rene Paul Acosta

Open Access Theses

It has been long hypothesized that large-scale topographic changes, such as the surface uplift of the Tibetan Plateau, impacts the development of the South Asian and East Asian monsoons and influences other monsoon regions. However, recent modeling has shown that spatial distribution of the global monsoon, which includes the South Asian and East Asian monsoons is largely unaffected by the elevation of the plateau. In this study, we present results from a series of modern day simulations using CESM1.0 in a mixed-layer (slab ocean) configuration. The Tibetan Plateau height is varied from double that of the modern maximum plateau elevation …

2000 Year Moisture Source Record From A Central Nevada Speleothem, Paul Pribyl

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study was to determine the moisture source of winter precipitation in the central Great Basin for the past 2000 years, and to elucidate the role of Pacific Ocean and North American climate variability modes in driving observed droughts of the region around the Medieval Climatic Anomaly (MCA, ~900-1300 CE). Here a high resolution (~2-4 year) precisely dated moisture source reconstruction is presented from the δ18O values of speleothem LC-1 collected from Leviathan Cave in central Nevada, which reveals significant δ18O variability. I attribute the δ18O variability to changes in winter-season moisture circulation over the past 2000 …