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2021

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Articles 661 - 685 of 685

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Tweetdrought: A Deep-Learning Drought Impacts Recognizer Based On Twitter Data, Beichen Zhang, Frank Schilder, Kelly Helm Smith, Michael Hayes, Sherri Harms, Tsegaye Tadesse Jan 2021

Tweetdrought: A Deep-Learning Drought Impacts Recognizer Based On Twitter Data, Beichen Zhang, Frank Schilder, Kelly Helm Smith, Michael Hayes, Sherri Harms, Tsegaye Tadesse

Drought Mitigation Center: Faculty Publications

Acquiring a better understanding of drought impacts becomes increasingly vital under a warming climate. Traditional drought indices describe mainly biophysical variables and not impacts on social, economic, and environmental systems. We utilized natural language processing and bidirectional encoder representation from Transformers (BERT) based transfer learning to fine-tune the model on the data from the news-based Drought Impact Report (DIR) and then apply it to recognize seven types of drought impacts based on the filtered Twitter data from the United States. Our model achieved a satisfying macro-F1 score of 0.89 on the DIR test set. The model was then applied to …


Evaluation Of Remotely Sensed Precipitation Estimates From The Nasa Power Project For Drought Detection Over Jordan, Muhammad Rasool Al‑Kilani, Michel Rahbeh, Jawad Al‑Bakri, Tsegaye Tadesse, Cody Knutson Jan 2021

Evaluation Of Remotely Sensed Precipitation Estimates From The Nasa Power Project For Drought Detection Over Jordan, Muhammad Rasool Al‑Kilani, Michel Rahbeh, Jawad Al‑Bakri, Tsegaye Tadesse, Cody Knutson

Drought Mitigation Center: Faculty Publications

Droughts can cause devastating impacts on water and land resources and therefore monitoring these events forms an integral part of planning. The most common approach for detecting drought events and assessing their intensity is use of the Standardized Precipitation Index (SPI), which requires abundant precipitation records at good spatial distribution. This may restrict SPI usage in many regions around the world, particularly in areas with limited numbers of ground meteorological stations. Therefore, the use of remotely sensed derived data of precipitation can contribute to drought monitoring. In this study, remotely sensed precipitation estimates from the POWER/Agroclimatology archive of NASA and …


Experiential Learning In Soil Science: Evaluating Soil Quality In South Wollo, Ethiopia, Melissa Allen, Martha Mamo, Shimelis Beyene, Teshome Regassa, Gandura O. Abagandura, Solomon Abreha, Anthony James Mucia, Tsegaye Tadesse Jan 2021

Experiential Learning In Soil Science: Evaluating Soil Quality In South Wollo, Ethiopia, Melissa Allen, Martha Mamo, Shimelis Beyene, Teshome Regassa, Gandura O. Abagandura, Solomon Abreha, Anthony James Mucia, Tsegaye Tadesse

Drought Mitigation Center: Faculty Publications

This study abroad program provided an opportunity to enhance the international experience and research skills of University of Nebraska-Lincoln (UNL) students within a multidisciplinary team’s research-education goal on improving food security in Ethiopia. The experiential study component of the project included preparatory sessions during the Fall 2015 Semester at the UNL followed by a four- to five-week fieldwork experience in Ethiopia. Teams from the UNL and an Ethiopian university participated in survey data collection and field soil evaluations from farms in the Gerado area of South Wollo, Ethiopia. Having students interact with farmers increased student self-confidence and enhanced their leadership …


Bioscatter Transport By Tropical Cyclones: Insights From 10 Years In The Atlantic Basin, Matthew S. Van Den Broeke Jan 2021

Bioscatter Transport By Tropical Cyclones: Insights From 10 Years In The Atlantic Basin, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Tropical cyclones (TCs) can transport birds and insects near their center of circulation. In this study, we examined the maximum altitude, area and density of the radar-derived bioscatter signature across a set of 42 TC centers of circulation sampled from 2011 to 2020. All TC events contained at least one time when a bioscatter signature was present. More intense hurricanes with closed eyes typically had taller and denser bioscatter signatures, and sometimes larger areas dominated by bioscatter. This indicated a larger number of organisms within the circulation of more intense hurricanes, supporting the speculation that those storms were most likely …


The 3H/3He Groundwater Age-Dating Method And Applications, Troy E. Gilmore, Mikaela L. Cherry, Didier Gastmans, Douglas Kip Solomon, Eric Christopher Humphrey Jan 2021

The 3H/3He Groundwater Age-Dating Method And Applications, Troy E. Gilmore, Mikaela L. Cherry, Didier Gastmans, Douglas Kip Solomon, Eric Christopher Humphrey

School of Natural Resources: Faculty Publications

Groundwater age-dating is an important tool for quantifying and managing water resources. Groundwater age is the elapsed time between recharge (at the land surface or water table) and the time when groundwater is sampled. If groundwater is sampled at the point of discharge from an aquifer, then the age represents the groundwater transit time. Groundwater that has recharged in recent decades is considered young groundwater. In many areas, the quality and quantity of young groundwater has been impacted by human activities and groundwater age-dating is useful for quantifying current and historical water and contaminant fluxes into and through aquifers. This …


Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan Jan 2021

Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan

Biological Sciences Faculty Publications

Phenotypic plasticity is one mechanism whereby species may cope with stressful environmental changes associated with climate change. Reef building corals present a good model for studying phenotypic plasticity because they have experienced rapid climate-driven declines in recent decades (within a single generation of many corals), often with differential survival among individuals during heat stress. Underlying differences in thermotolerance may be driven by differences in baseline levels of environmental stress, including pollution stress. To examine this possibility, acute heat stress experiments were conducted on Acropora hyacinthus from 10 sites around Tutuila, American Samoa with differing nutrient pollution impact. A threshold-based heat …


Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby Jan 2021

Scaling The Effects Of Ocean Acidification On Coral Growth And Coral-Coral Competition On Coral Community Recovery, Nicolas R. Evensen, Yves-Marie Bozec, Peter J. Edmunds, Peter J. Mumby

Biological Sciences Faculty Publications

Ocean acidification (OA) is negatively affecting calcification in a wide variety of marine organisms. These effects are acute for many tropical scleractinian corals under short-term experimental conditions, but it is unclear how these effects interact with ecological processes, such as competition for space, to impact coral communities over multiple years. This study sought to test the use of individual-based models (IBMs) as a tool to scale up the effects of OA recorded in short-term studies to community-scale impacts, combining data from field surveys and mesocosm experiments to parameterize an IBM of coral community recovery on the fore reef of Moorea, …


The Conservation Status Of Marine Biodiversity Of The Western Indian Ocean, R. Bullock, Gina Ralph, E. Stump, F. Al Abdali, J. Al Asfoor, B. Al Buwaiqi, A. Al Kindi, A. Ambuali, Tiffany Birge, P. Borsa, F. Di Dario, B. Everett, S. Fennessy, C. Fonseca, Claire Gorman, A. Govender, H. Ho, W. Holleman, N. Jiddawi, M. Khan, H. Larson, Christi Linardich, P. Matiku, K. Matsuura, C. Maunde, H. Motomura, T. Munroe, R. Nair, C. Obota, B. Polidoro, B. Russell, S. Shaheen, Y. Sithole, W. Smith-Vaniz, F. Uiblein, S. Weerts, A. Williams, S. Yahya, Kent Carpenter Jan 2021

The Conservation Status Of Marine Biodiversity Of The Western Indian Ocean, R. Bullock, Gina Ralph, E. Stump, F. Al Abdali, J. Al Asfoor, B. Al Buwaiqi, A. Al Kindi, A. Ambuali, Tiffany Birge, P. Borsa, F. Di Dario, B. Everett, S. Fennessy, C. Fonseca, Claire Gorman, A. Govender, H. Ho, W. Holleman, N. Jiddawi, M. Khan, H. Larson, Christi Linardich, P. Matiku, K. Matsuura, C. Maunde, H. Motomura, T. Munroe, R. Nair, C. Obota, B. Polidoro, B. Russell, S. Shaheen, Y. Sithole, W. Smith-Vaniz, F. Uiblein, S. Weerts, A. Williams, S. Yahya, Kent Carpenter

Biological Sciences Faculty Publications

The Western Indian Ocean (WIO) is comprised of productive and highly diverse marine ecosystems that are rich sources of food security, livelihoods, and natural wonder. The ecological services that species provide are vital to the productivity of these ecosystems and healthy biodiversity is essential for the continued support of economies and local users. The stability of these valuable resources, however, is being eroded by growing threats to marine life from overexploitation, habitat degradation and climate change, all of which are causing serious reductions in marine ecosystem services and the ability of these ecosystems to support human communities. Quantifying the impacts …


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, …


Elevating Dissolved Oxygen—Reflections On Developing And Using Long-Term Data, Nancy N. Rabalais Jan 2021

Elevating Dissolved Oxygen—Reflections On Developing And Using Long-Term Data, Nancy N. Rabalais

Gulf and Caribbean Research

This prospectus took me about as long to generate as my 36—year record of working on the issue of northern Gulf of Mexico (nGOM) oxygen deficiency, or so I felt. There was so much to cover, but I focused on the issue of hypoxia on the Louisiana continental shelf from the early 1980s to present and my participation in the research and outreach. Not that I was ignoring other aspects of my academic research career (e.g., stone crab populations and their differences in physiology and larval development along the nGOM coast; settlement of crab megalopae, especially blue crabs, on artificial …


Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri Jan 2021

Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri

Graduate College Dissertations and Theses

As the ripple-effects of a changing climate shape our planet, understanding relationships between agriculture and climate change is critical. With agricultural practices shaping soils on over a third of the earth’s land surface, the soils and lands where food is produced are integral grounds for examining these relationships. While not all humans practice agriculture in similar or damaging ways, nevertheless, dominant agricultural practices are displacing beings and ecosystems and perturbing global nutrient cycles across the planet. These entwined imbalances of dominance and nutrients result in flows of excess nitrogen, phosphorus, and carbon that are responsible for nearly three-fourths of the …


Evaluation Of A Low-Cost Uas And Phenocams For Measuring Grapevine Greenness, Timothy J. Hoheneder Jan 2021

Evaluation Of A Low-Cost Uas And Phenocams For Measuring Grapevine Greenness, Timothy J. Hoheneder

Graduate Theses, Dissertations, and Problem Reports

Unpersoned aerial systems (UAS) could provide winegrowers with the potential to monitor vineyard productivity with ultra-high-resolution imagery and low operational costs. This ability could prove particularly valuable in the challenging cool-climate viticultural areas of Appalachia. Especially in this mountainous region of increasingly variable microclimates, there could be of great value from an ability to use UAS-measured greenness to monitor wine grape phenology and predict harvest quality and quantity. In this study, I assess how UAS-measured greenness relates to three complementary measures of field-based: leaf angle measurements, phenocam measured greenness, and leaf spectral measurements of greenness. After correlating these field-based measures …


Investigating The Phase Of Green Leaf Volatile Derived Secondary Organic Aerosol Using An Electrical Low Pressure Impactor, Kevin Fischer Jan 2021

Investigating The Phase Of Green Leaf Volatile Derived Secondary Organic Aerosol Using An Electrical Low Pressure Impactor, Kevin Fischer

Graduate College Dissertations and Theses

Airborne particulate matter consists of small particles suspended in the air and is a ubiquitous component of the Earth’s atmosphere. These particles, known as aerosols, broadly affect both human health and the global climate. Secondary organic aerosol (SOA), a subset of atmospheric aerosol, are produced by the gas phase oxidation of volatile organic compounds (VOCs) originating from anthropogenic and biogenic sources. Of particular interest are a sub class of biogenic VOCs released by stressed plants, green leaf volatiles (GLVs), which are susceptible to oxidation via ozonolysis and form SOA. While important strides have been made in better understanding SOA, many …


Mendums Pond 2021 Water Quality Highlight Report, Robert Craycraft, Amanda Mcquaid Jan 2021

Mendums Pond 2021 Water Quality Highlight Report, Robert Craycraft, Amanda Mcquaid

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Mendums Pond (Barrington, NH) for 2021.


Unexpected Role Of Communities Colonizing Dead Coral Substrate In The Calcification Of Coral Reefs, Manoela Romanó De Orte, David A. Koweek, Tyler Cyronak, Yuichiro Takeshita, Alyssa Griffin, Kennedy Wolfe, Alina Szmant, Robert Whitehead, Rebecca Albright, Ken Caldeira Jan 2021

Unexpected Role Of Communities Colonizing Dead Coral Substrate In The Calcification Of Coral Reefs, Manoela Romanó De Orte, David A. Koweek, Tyler Cyronak, Yuichiro Takeshita, Alyssa Griffin, Kennedy Wolfe, Alina Szmant, Robert Whitehead, Rebecca Albright, Ken Caldeira

Marine & Environmental Sciences Faculty Articles

Global and local anthropogenic stressors such as climate change, acidification, overfishing, and pollution are expected to shift the benthic community composition of coral reefs from dominance by calcifying organisms to dominance by non-calcifying algae. These changes could reduce the ability of coral reef ecosystems to maintain positive net calcium carbonate accretion. However, relationships between community composition and calcification rates remain unclear. We performed field experiments to quantify the metabolic rates of the two most dominant coral reef substrate types, live coral and dead coral substrate colonized by a mixed algal assemblage, using a novel underwater respirometer. Our results revealed that …


Deep-Pelagic Research In The Gulf Of Mexico: Ten Years And Counting…, Tracey Sutton Jan 2021

Deep-Pelagic Research In The Gulf Of Mexico: Ten Years And Counting…, Tracey Sutton

Marine & Environmental Sciences Faculty Articles

No abstract provided.


Artificial Reefs: A History, A Science, A Technology, Mairead D. Farrell Jan 2021

Artificial Reefs: A History, A Science, A Technology, Mairead D. Farrell

Honors Theses

Over the past 60 years, artificial reefs have expanded beyond the definition of a technology, and in turn have developed into a unique branch of marine science. To better emphasize this growth and separation, a brief history of artificial reef development and usage in chapter two shows some of the key shifts over time in this technology’s purpose and the materials used to achieve that goal. Likewise, to indicate the scientific development of artificial reefs as a branch of marine science, their usage for discovery and research is recorded in chapter three, along with the exponential increase in published scientific …


The Impact Of Initial Snow Conditions On The Numerical Weather Simulation Of A Northern Rockies Atmospheric River, William Rudisill, Alejandro Flores, James Mcnamara Jan 2021

The Impact Of Initial Snow Conditions On The Numerical Weather Simulation Of A Northern Rockies Atmospheric River, William Rudisill, Alejandro Flores, James Mcnamara

Geosciences Faculty Publications and Presentations

Snow’s thermal and radiative properties strongly impact the land surface energy balance and thus the atmosphere above it. Land surface snow information is poorly known in mountainous regions. Few studies have examined the impact of initial land surface snow conditions in high-resolution, convection-permitting numerical weather prediction models during the midlatitude cool season. The extent to which land surface snow influences atmospheric energy transport and subsequent surface meteorological states is tested using a high-resolution (1 km) configuration of the Weather Research and Forecasting (WRF) Model, for both calm conditions and weather characteristic of a warm late March atmospheric river. A set …


Pattern-Based Downscaling Of Snowpack Variability In The Western United States, Nicolas Gauthier, Kevin J. Anchukaitis, Bethany Coulthard Jan 2021

Pattern-Based Downscaling Of Snowpack Variability In The Western United States, Nicolas Gauthier, Kevin J. Anchukaitis, Bethany Coulthard

Geoscience Faculty Research

The decline in snowpack across the western United States is one of the most pressing threats posed by climate change to regional economies and livelihoods. Earth system models are important tools for exploring past and future snowpack variability, yet their coarse spatial resolutions distort local topography and bias spatial patterns of accumulation and ablation. Here, we explore pattern-based statistical downscaling for spatially-continuous interannual snowpack estimates. We find that a few leading patterns capture the majority of snowpack variability across the western US in observations, reanalyses, and free-running simulations. Pattern-based downscaling methods yield accurate, high resolution maps that correct mean and …


Status Reports Of The Fisheries And Aquatic Resources Of Western Australia 2020/21, S.J. Newman, B.S. Wise, K.G. Santoro, D.J. Gaughan Jan 2021

Status Reports Of The Fisheries And Aquatic Resources Of Western Australia 2020/21, S.J. Newman, B.S. Wise, K.G. Santoro, D.J. Gaughan

Status reports of the fisheries and aquatic resources

The Status Reports of the Fisheries and Aquatic Resources of Western Australia (SRFAR) provide an annual update on the state of the fish stocks and other aquatic resources of Western Australia (WA). These reports outline the most recent assessments of the cumulative risk status for each of the aquatic resources (assets) within WA’s six Bioregions using an Ecosystem Based Fisheries Management (EBFM) approach. The Departments’ risk based EBFM framework is the State government’s basis for management of all Western Australia’s aquatic resources.


Response Of Coastal Ichthyoplankton Assemblages Off Northern California To Seasonal Oceanographic And Climate Variability, Blair M. Winnacott Jan 2021

Response Of Coastal Ichthyoplankton Assemblages Off Northern California To Seasonal Oceanographic And Climate Variability, Blair M. Winnacott

Cal Poly Humboldt theses and projects

This study analyzed samples collected along the Trinidad Head Line (41°N) to characterize variability in the ichthyoplankton assemblage in coastal waters off northern California from late 2007 through 2019, a period during which a major marine heatwave (MHW; late 2014-16) strongly perturbed the ecosystem. I augmented visual identification with genetic techniques to resolve the species composition of visually cryptic larval rockfishes (Sebastes spp.). While taxonomic composition off northern California was largely similar to studies off Oregon and Washington, and cross-shelf structure and seasonal patterns in species’ abundance were generally consistent with the distribution and phenology of parental stocks, interannual …


Inference Of Surface Velocities From Oblique Time Lapse Photos And Terrestrial Based Lidar At The Helheim Glacier, Franklyn T. Dunbar Ii Jan 2021

Inference Of Surface Velocities From Oblique Time Lapse Photos And Terrestrial Based Lidar At The Helheim Glacier, Franklyn T. Dunbar Ii

Graduate Student Theses, Dissertations, & Professional Papers

Using time dependent observations derived from terrestrial LiDAR and oblique
time-lapse imagery, we demonstrate that a Bayesian approach to glacial motion es-
timation provides a concise way to incorporate multiple data products into a single
motion estimation procedure effectively producing surface velocity estimates with
an associated uncertainty. This approach brings both improved computational effi-
ciency, and greater scalability across observational time-frames when compared to
existing methods. To gauge efficacy, we apply these methods to a set of observa-
tions from the Helheim Glacier, a critical actor in contemporary mass loss trends
observed in the Greenland Ice Sheet. We find that …


Arctic Observations And Numerical Simulations Of Surface Wind Effects On Multi-Angle Snowflake Camera Measurements, Kyle E. Fitch, Chaoxun Hang, Ahmad Talaei, Timothy Garrett Jan 2021

Arctic Observations And Numerical Simulations Of Surface Wind Effects On Multi-Angle Snowflake Camera Measurements, Kyle E. Fitch, Chaoxun Hang, Ahmad Talaei, Timothy Garrett

Faculty Publications

Ground-based measurements of frozen precipitation are heavily influenced by interactions of surface winds with gauge-shield geometry. The Multi-Angle Snowflake Camera (MASC), which photographs hydrometeors in free-fall from three different angles while simultaneously measuring their fall speed, has been used in the field at multiple midlatitude and polar locations both with and without wind shielding. Here, we present an analysis of Arctic field observations – with and without a Belfort double Alter shield – and compare the results to computational fluid dynamics (CFD) simulations of the airflow and corresponding particle trajectories around the unshielded MASC. MASC-measured fall speeds compare well with …


Down In Arms: Marine Climate Stress Inhibits Growth And Calcification Of Regenerating Asterias Forbesi (Echinodermata: Asteroidea) Arms, Hannah L. Randazzo Jan 2021

Down In Arms: Marine Climate Stress Inhibits Growth And Calcification Of Regenerating Asterias Forbesi (Echinodermata: Asteroidea) Arms, Hannah L. Randazzo

Honors Projects

Anthropogenic CO2 is changing the pCO2, temperature, and carbonate chemistry of seawater. These processes are termed ocean acidification (OA) and ocean warming. Previous studies suggest two opposing hypotheses for the way in which marine climate stress will influence echinoderm calcification, metabolic efficiency, and reproduction: either an additive or synergistic effect. Sea stars have a regenerative capacity, which may be particularly affected while rebuilding calcium carbonate arm structures, leading to changes in arm growth and calcification. In this study, Asterias forbesi were exposed to ocean water of either ambient, high temperature, high pCO2, or high temperature …


Ua12/13 Student Affairs - Sustainability, Wku Archives Jan 2021

Ua12/13 Student Affairs - Sustainability, Wku Archives

WKU Archives Collection Inventories

Records created by and about the Office of Sustainability.