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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell May 2023

The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell

School of Natural Resources: Dissertations, Theses, and Student Research

Drought is characterized by periods of below average precipitation. There are five major types of drought recognized in the literature: meteorological, hydrological, agricultural, socioeconomic, and ecological. A relatively new concept in the drought literature is “snow drought.” A key part of the definition of drought is that it is not always accompanied by extreme heat. This means drought can occur even in cold climates, cold seasons, and higher latitudes and altitudes, like Alaska. Drought is a natural part of climate variability, but Alaska’s climate is changing faster than any other state in the United States. Alaska is no stranger to …


The Influence Of Complex Coastlines On The Sea Breeze And Convection Initiation In Coastal North Carolina, Logan Howard, Adam L. Houston Mar 2023

The Influence Of Complex Coastlines On The Sea Breeze And Convection Initiation In Coastal North Carolina, Logan Howard, Adam L. Houston

Honors Theses

The sea breeze is a common phenomenon in coastal regions around the world. Their development and propagation can be treated as a density current. It is well known that many factors influence density current propagation, including wind. Depending on the orientation, the wind speed and shear can enhance or inhibit the development of the sea breeze. In places like eastern North Carolina, complex coastal geography can create river and sound breezes that, upon collision, have the potential to initiate thunderstorms. Using Cloud Model 1, simulations were conducted to model the behavior of the sea breezes in eastern North Carolina and …


An Investigation Of Water Obstructions And Related Weather Conditions For Nebraska Roadways, Logan Bundy Apr 2022

An Investigation Of Water Obstructions And Related Weather Conditions For Nebraska Roadways, Logan Bundy

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

Roadway resilience across the 10,000 miles of road and 3,500 bridges in Nebraska is critical to the economic success of production and logistics. In a state where historical flooding scenarios, such as the one in March 2019 that caused $150 million in damage, could potentially be increasing, it has become essential to understand the spatial and temporal distribution of high-frequency water obstruction areas on roadways. Using Nebraska Department of Transportation (NDOT) historical water obstruction data from June 2016 through August 2021, statistical and spatial analyses were conducted to quantify the relationship between water obstructions and their associated meteorological conditions, and …


Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel Dec 2020

Impacts Of Environmental Conditions On Fleas In Black-Tailed Prairie Dog Burrows, Julia E. Poje, Tonie Rocke, Michael D. Samuel

United States Geological Survey: Staff Publications

Sylvatic plague, caused by the bacterium Yersinia pestis and transmitted by fleas, occurs in prairie dogs of the western United States. Outbreaks can devastate prairie dog communities, often causing nearly 100% mortality. Three competent flea vectors, prairie dog specialists Oropsylla hirsuta and O. tuberculata, and generalist Pulex simulans, are found on prairie dogs and in their burrows. Fleas are affected by climate, which varies across the range of black-tailed prairie dogs (Cynomys ludovicianus), but these effects may be ameliorated somewhat due to the burrowing habits of prairie dogs. Our goal was to assess how temperature and precipitation …


Anthropogenic Change On The Distribution Of Marine Megafauna And Their Prey, Baylie Fadool Oct 2020

Anthropogenic Change On The Distribution Of Marine Megafauna And Their Prey, Baylie Fadool

Honors Theses

Anthropogenic change is impacting the distribution and survival of marine megafauna and their prey. Humans are changing every aspect of the marine environment, with effects reaching as large as changing the composition of marine environments to directly overexploiting species through the fishing industry. The role that marine megafauna play in balancing ecosystems, including as top apex predators, leads to detrimental results in the absences and population declines of these species. Migrations and declines due to threats on marine apex predator species will alter their environments by causing mesopredator release and changes in community structure, which is often associated with reduced …


Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major Jan 2020

Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major

United States Geological Survey: Staff Publications

Sagebrush ecosystems of the western United States can transition from extended periods of relatively stable conditions to rapid ecological change if acute disturbances occur. Areas dominated by native sagebrush can transition from species-rich native systems to altered states where non-native annual grasses dominate, if resistance to annual grasses is low. The non-native annual grasses provide relatively little value to wildlife, livestock, and humans and function as fuel that increases fire frequency. The more land area covered by annual grasses, the higher the potential for fire, thus reducing the potential for native vegetation to reestablish, even when applying restoration treatments. Mapping …


Changes In Mammalian Abundance Through The Eocene-Oligocene Climate Transition In The White River Group Of Nebraska, Usa, Robert Gillham Jul 2019

Changes In Mammalian Abundance Through The Eocene-Oligocene Climate Transition In The White River Group Of Nebraska, Usa, Robert Gillham

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

Marine records show major cooling during the Eocene-Oligocene Climate Transition (EOCT). Most proxy studies in the White River Group suggest drying across the EOCT, and some suggest cooling. The lower resolution continental record has hindered a direct correlation of the marine climate record to Nebraska. I explore various correlation schemes and what they imply for faunal changes. This study compiles and analyzes data from 4,875 specimens in the University of Nebraska State Museum (UNSM) collection to test the hypothesis that climate change across the Eocene-Oligocene (E-O) boundary caused significant abundance changes in mammals. A series of binning schemes was created. …


Land Use Land Cover Change Effects On Southern Great Plains Precipitation, Alexandra Caruthers Dec 2017

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 …


Nres/Metr/Bsen 479/879: Hydroclimatology—A Peer Review Of Teaching Project Benchmark Portfolio, Francisco Munoz-Arriola Jan 2016

Nres/Metr/Bsen 479/879: Hydroclimatology—A Peer Review Of Teaching Project Benchmark Portfolio, Francisco Munoz-Arriola

UNL Faculty Course Portfolios

Rising temperatures and extreme hydrometeorological and climate events are evidences of a changing climate. An increasing population together with their demands for food, energy and water make changes in climate evidence the need to train a new generation of multidisciplinary professionals with a clear understanding of the effects of a changing climate in their activities. Historically, climate sciences were used for scientific and weather operational contexts and engineers applied stationary assumptions for multi-term planning. My goal is to identify elements built from classroom experiences about (a) the suitability of a hydroclimatology course for engineers and scientists; (b) the multidisciplinary skills; …


Springtime Melt Onset On Arctic Sea Ice From Satellite Observations And Related Atmospheric Conditions, Angela C. Bliss May 2015

Springtime Melt Onset On Arctic Sea Ice From Satellite Observations And Related Atmospheric Conditions, Angela C. Bliss

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

The timing of snowmelt onset (MO) on Arctic sea ice derived from passive microwave satellite data is examined by determining the melting area (in km2) on a daily basis for the spring and summer melt season months over the 1979 – 2012 data record. The date of MO on Arctic sea ice has important implications for the amount of total solar energy absorbed by the ice-ocean system in a given year. Increasingly early mean MO dates have been recorded over the 34-year data record as evidenced by statistically significant trends of 6.6 days decade-1 over the extent …


Springtime Atmospheric Responses To North Atlantic Sst Anomalies In Idealized Gcm Experiments: Northern Hemisphere Circulation And North American Precipitation, Michael C. Veres Jul 2014

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 …


Metr 200: Weather And Climate—A Peer Review Of Teaching Project Benchmark Portfolio, Matthew S. Van Den Broeke Jan 2013

Metr 200: Weather And Climate—A Peer Review Of Teaching Project Benchmark Portfolio, Matthew S. Van Den Broeke

UNL Faculty Course Portfolios

This benchmark portfolio is meant to be an assessment of how well the objectives of METR 200 (Weather and Climate) are being attained by students in several classifications of academic major. Students from a wide range of backgrounds enroll in this course as a general science elective, and for many, it will be the only science course taken in college. Thus, it is important that course material be sufficiently accessible for all students, while providing meaningful information which will be applicable by students of all backgrounds once they leave the course. In this portfolio, an analysis will be presented showing …


Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres Dec 2011

Atlantic Multidecadal Oscillation-Forced Regional Summertime Precipitation Variations In The Central United States, Michael C. Veres

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

The purpose of this research is to identify the regional mechanisms by which the Atlantic Multidecadal Oscillation (AMO) influences summer (June-August) precipitation in the central U.S. This was accomplished by running two different sets of simulations using the Weather Research and Forecasting (WRF) regional climate model, one forced by observations and the other forced only by variations in the AMO as obtained via a global climate model (GCM). The results reveal a complex set of mechanisms active in the lower and middle troposphere by which the AMO influences summer circulation and precipitation in the central U.S. During the cold phase …


Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf Jan 2011

Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf

Drought Mitigation Center: Faculty Publications

Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …


An Intercomparison Of Regional Atmospheric Circulation And The Melt Season Loss Of Arctic Snow Cover And Sea Ice Extent Across The Land-Ocean Boundary, Angela C. Bliss Aug 2010

An Intercomparison Of Regional Atmospheric Circulation And The Melt Season Loss Of Arctic Snow Cover And Sea Ice Extent Across The Land-Ocean Boundary, Angela C. Bliss

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

This study is designed to compare the monthly continental snow cover and sea ice extent loss in the Arctic with regional atmospheric conditions including: mean sea level pressure, 925 hPa air temperature, and mean wind direction among others during the melt season (March-August) over the 29-year study period 1979-2007. Little research has gone into studying the concurrent variations in the annual loss of continental snow cover and sea ice extent across the land-ocean boundary, since these data are largely stored in incompatible formats. However, the analysis of these data, averaged spatially over three autonomous study regions located in Siberia, North …


Effects Of Lightning And Other Meteorological Factors On Fire Activity In The North American Boreal Forest: Implications For Fire Weather Forecasting, David Peterson, Jun Wang, Charles Ichoku, Lorraine Remer Jan 2010

Effects Of Lightning And Other Meteorological Factors On Fire Activity In The North American Boreal Forest: Implications For Fire Weather Forecasting, David Peterson, Jun Wang, Charles Ichoku, Lorraine Remer

Department of Earth and Atmospheric Sciences: Faculty Publications

The effects of lightning and other meteorological factors on wildfire activity in the North American boreal forest are statistically analyzed during the fire seasons of 2000–2006 through an integration of the following data sets: the MODerate Resolution Imaging Spectroradiometer (MODIS) level 2 fire products, the 3-hourly 32-km gridded meteorological data from North American Regional Reanalysis (NARR), and the lightning data collected by the Canadian Lightning Detection Network (CLDN) and the Alaska Lightning Detection Network (ALDN). Positive anomalies of the 500 hPa geopotential height field, convective available potential energy (CAPE), number of cloud-to-ground lightning strikes, and the number of consecutive dry …


Impacts Of Meteorological Factors On Modis-Observed Fire Activity In The North American Boreal Forest: The Role Of Lightning, David A. Peterson Oct 2009

Impacts Of Meteorological Factors On Modis-Observed Fire Activity In The North American Boreal Forest: The Role Of Lightning, David A. Peterson

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

The meteorological impact on wildfire activity in the North American boreal forest during the fire seasons of 2000 – 2006 is statistically analyzed through an integration of the following data sets: the MODerate Resolution Imaging Spectroradiometer (MODIS) level 2 fire products, the 3-hourly 32-km gridded meteorological data from North American Regional Reanalysis (NARR), the instantaneous lightning data collected by the Canadian Lightning Detection Network (CLDN), and the Alaska Lightning Detection Network (ALDN). Positive anomalies of the 500 hpa geopotential height field, convective available potential energy (CAPE), number of cloud-to-ground lightning strikes, and the number of consecutive dry days are found …


A Century Of Climate Change For Fairbanks, Alaska, Gerd Wendler, Martha Shulski Jan 2009

A Century Of Climate Change For Fairbanks, Alaska, Gerd Wendler, Martha Shulski

School of Natural Resources: Faculty Publications

Climatological observations are available for Fairbanks, Interior Alaska, for up to 100 years. This is a unique data set for Alaska, insofar as it is of relatively high quality and without major breaks. Applying the best linear fit, we conclude that the mean annual temperature rose from -3.6°C to -2.2°C over the century, an increase of 1.4°C (compared to 0.8°C worldwide). This comparison clearly demonstrates the well-known amplification or temperature change for the polar regions. The observed temperature increase is neither uniform over the time period nor uniform throughout the course of a year. The winter, spring, and summer seasons …