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Articles 661 - 690 of 3306

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

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 …


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor Photographs” was developed by the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping/Joint Hydrographic Center (CCOM/JHC). The field campaign was conducted to provide ground truth for surficial geology maps for the continental shelf off New Hampshire (NH) and focused on the inner shelf between the coast and the Isles of Shoals. Station locations were chosen where high-resolution bathymetry was available, including multibeam echosounder (MBES) surveys conducted by the UNH CCOM/JHC Hydrographic Field Course (Ocean Engineering 972), MBES surveys by the NOAA National Ocean Service (NOS), …


A Model-Based Exploratory Study Of Sulfur Dioxide Dispersions From Concentrated Animal Feeding Operations In The Southeastern United States, Jesse Winchester, Rezaul Mahmood, William Rodgers, Philip J. Silva, Nanh Lovanh, Joshua D. Durkee, John Loughrin Jan 2021

A Model-Based Exploratory Study Of Sulfur Dioxide Dispersions From Concentrated Animal Feeding Operations In The Southeastern United States, Jesse Winchester, Rezaul Mahmood, William Rodgers, Philip J. Silva, Nanh Lovanh, Joshua D. Durkee, John Loughrin

High Plains Regional Climate Center: Staff Publications

In the Southeastern U. S. there are Concentrated Animal Feeding Operations (CAFOs) that emit a variety of gases, including SO2. Sulfur is emitted as reduced sulfur compounds and can react in the atmosphere to produce SO2. It is expected that the concentra­tion and spread of SO2 emissions from these sources would differ between wet and dry periods. In this research, SO2 emissions from locations representing CAFOs and its dispersion over the south­eastern U.S. were simulated through sensitivity experiments using the Weather Research and Forecasting-Chemistry (WRF- Chem) model. Simulations were performed for dry periods and …


New Hampshire Continental Shelf Geophysical Database: 2012-2013 Newbex Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2012-2013 Newbex Field Campaign – Seafloor Photographs And Sediment Data, Larry G. Ward, Zachary S. Mcavoy, Rachel C. Morrison

Data Catalog

An approximately 4.5 km transect running from lower Portsmouth Harbor seaward onto the inner continental shelf was established to serve as the field site for the Newcastle Backscatter Experiment (NEWBEX). Acoustic backscatter measurements were made along the transect to examine relationships between backscatter and seafloor properties. This transect takes advantage of the diversity and heterogeneity of bottom types in lower Portsmouth Harbor and approach. In support of NEWBEX, a field campaign was undertaken to describe the sedimentologic characteristics of the seafloor along the transect. A total of five cruises were carried out approximately seasonally on November 26, 2012 and June …


New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy Jan 2021

New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign – Seafloor And Sample Photographs And Sediment Data, Larry G. Ward, Rachel C. Morrison, Zachary S. Mcavoy

Data Catalog

The "New Hampshire Continental Shelf Geophysical Database: 2016-2017 Field Campaign - Seafloor and Sample Photographs and Sediment Data " contains photographs of the seafloor from sampling locations, photographs of the sediment samples, and grain size data from a major field campaign conducted in 2016- 2017 and from the UNH Ocean Engineering 972 Hydrographic Field Course classes in 2012, 2014, and 2018. In total, sixteen one-day cruises provided 150 samples for grain size analysis. The database provides complete descriptions for each sample including identification, station and sample characteristics, sediment classifications, grain size statistics, and grain size distribution. Presented here are tables …


Mapping Michigan's Historic Coastlines, Ryan A. Williams Jan 2021

Mapping Michigan's Historic Coastlines, Ryan A. Williams

Dissertations, Master's Theses and Master's Reports

This five-year project, sponsored by the Michigan Department of Environment, Great Lakes, and Energy, is working to map how Michigan’s Great Lakes shorelines have changed over the past 80+ years. Products of this project include publicly available digital, georeferenced, historic aerial photography datasets, as well as map layers depicting the locations of historic shorelines and bluff lines from 1938, 1980, 2009, 2016, 2018, and 2020. Additional products include bluff retreat risk areas, shoreline rate of change map layers, and tools to assist in the development of future Coastal Vulnerability Index projects for the Great Lakes. All products are available as …


The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes Jan 2021

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO4 complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …


Bioactive Trace Metals And Their Isotopes As Paleoproductivity Proxies: An Assessment Using Geotraces-Era Data, T. J. Horner, S. H. Little, T. W. Conway, J. R. Farmer, Jennifer E. Hertzberg, D. J. Janssen, A.J.M. Lough, J.L. Mckay, A. Tessin, S.J.G. Galer, S. L. Jaccard, F. Lacan, A. Paytan, K. Wuttig, Geotraces-Pages Biological Productivity Working Group Members Jan 2021

Bioactive Trace Metals And Their Isotopes As Paleoproductivity Proxies: An Assessment Using Geotraces-Era Data, T. J. Horner, S. H. Little, T. W. Conway, J. R. Farmer, Jennifer E. Hertzberg, D. J. Janssen, A.J.M. Lough, J.L. Mckay, A. Tessin, S.J.G. Galer, S. L. Jaccard, F. Lacan, A. Paytan, K. Wuttig, Geotraces-Pages Biological Productivity Working Group Members

OES Faculty Publications

Phytoplankton productivity and export sequester climatically significant quantities of atmospheric carbon dioxide as particulate organic carbon through a suite of processes termed the biological pump. Constraining how the biological pump operated in the past is important for understanding past atmospheric carbon dioxide concentrations and Earth's climate history. However, reconstructing the history of the biological pump requires proxies. Due to their intimate association with biological processes, several bioactive trace metals and their isotopes are potential proxies for past phytoplankton productivity, including iron, zinc, copper, cadmium, molybdenum, barium, nickel, chromium, and silver. Here, we review the oceanic distributions, driving processes, and depositional …


Constraining 20th‐Century Sea‐Level Rise In The South Atlantic Ocean, Thomas Frederikse, Surendra Adhikari, Tim J. Daley, Sönke Dangendorf, Roland Gehrels, Felix Landerer, Marta Marcos, Thomas L. Newton, Graham Rush, Aimée B.A. Slangen, Guy Wöppelmann Jan 2021

Constraining 20th‐Century Sea‐Level Rise In The South Atlantic Ocean, Thomas Frederikse, Surendra Adhikari, Tim J. Daley, Sönke Dangendorf, Roland Gehrels, Felix Landerer, Marta Marcos, Thomas L. Newton, Graham Rush, Aimée B.A. Slangen, Guy Wöppelmann

OES Faculty Publications

Sea level in the South Atlantic Ocean has only been measured at a small number of tide-gauge locations, which causes considerable uncertainty in 20th-century sea-level trend estimates in this basin. To obtain a better-constrained sea-level trend in the South Atlantic Ocean, this study aims to answer two questions. The first question is: can we combine new observations, vertical land motion estimates, and information on spatial sampling biases to obtain a likely range of 20th-century sea-level rise in the South Atlantic? We combine existing observations with recovered observations from Dakar and a high-resolution sea-level reconstruction based on salt-marsh sediments from the …


Microbially Induced Sedimentary Structures In Clastic Deposits: Implication For The Prospection For Fossil Life On Mars, Nora Noffke Jan 2021

Microbially Induced Sedimentary Structures In Clastic Deposits: Implication For The Prospection For Fossil Life On Mars, Nora Noffke

OES Faculty Publications

Abundant and well-preserved fossil microbenthos occurs in siliciclastic deposits of all Earth ages, from the early Archean to today. Studies in modern settings show how microbenthos responds to sediment dynamics by baffling and trapping, binding, biostabilization, and growth. Results of this microbial-sediment interaction are microbially induced sedimentary structures (MISS). Successful prospection for rich MISS occurrences in the terrestrial lithological record requires unraveling genesis and taphonomy of MISS, both of which are defined only by a narrow range of specific conditions. These conditions have to coincide with high detectability which is a function of outcrop quality, bedding character, and rock type. …


Neodymium Isotope Geochemistry Of A Subterranean Estuary, Darren A. Chevis, T. Jade Mohajerin, Ningfang Yang, Jaye E. Cable, E. Troy Rasbury, Sidney R. Hemming, David J. Burdige, Jonathan B. Martin, Christopher D. White, Karen H. Johannesson Jan 2021

Neodymium Isotope Geochemistry Of A Subterranean Estuary, Darren A. Chevis, T. Jade Mohajerin, Ningfang Yang, Jaye E. Cable, E. Troy Rasbury, Sidney R. Hemming, David J. Burdige, Jonathan B. Martin, Christopher D. White, Karen H. Johannesson

OES Faculty Publications

Rare earth elements (REE) and Nd isotope compositions of surface and groundwaters from the Indian River Lagoon in Florida were measured to investigate the influence of submarine groundwater discharge (SGD) on these parameters in coastal waters. The Nd flux of the terrestrial component of SGD is around 0.7 ± 0.03 μmol Nd/day per m of shoreline across the nearshore seepage face of the subterranean estuary. This translates to a terrestrial SGD Nd flux of 4 ± 0.2 mmol/day for the entire 5,880 m long shoreline of the studied portion of the lagoon. The Nd flux from bioirrigation across the nearshore …


Radium Isotopes As Submarine Groundwater Discharge (Sgd) Tracers: Review And Recommendations, J. Garcia-Orellana, V. Rodellas, Joseph Tamborski, M. Diego-Feliu, P. Van Beek, Y. Weinstein, M. Charette, A. Alorda-Kleinglass, H.A. Michael, T. Stieglitz, J. Scholten Jan 2021

Radium Isotopes As Submarine Groundwater Discharge (Sgd) Tracers: Review And Recommendations, J. Garcia-Orellana, V. Rodellas, Joseph Tamborski, M. Diego-Feliu, P. Van Beek, Y. Weinstein, M. Charette, A. Alorda-Kleinglass, H.A. Michael, T. Stieglitz, J. Scholten

OES Faculty Publications

Submarine groundwater discharge (SGD) is now recognized as an important process of the hydrological cycle worldwide and plays a major role as a conveyor of dissolved compounds to the ocean. Naturally occurring radium isotopes (Ra-223, Ra-224, Ra-226 and Ra-228) are widely employed geochemical tracers in marine environments. Whilst Ra isotopes were initially predominantly applied to study open ocean processes and fluxes across the continental margins, their most common application in the marine environment has undoubtedly become the identification and quantification of SGD. This review focuses on the application of Ra isotopes as tracers of SGD and associated inputs of water …


Detrital Neodymium And (Radio)Carbon As Complementary Sedimentary Bedfellows? The Western Arctic Ocean As A Testbed, Melissa S. Schwab, Jörg D. Rickli, Robie W. Macdonald, H. Rodger Harvey, Negar Haghipour, Timothy I. Eglinton Jan 2021

Detrital Neodymium And (Radio)Carbon As Complementary Sedimentary Bedfellows? The Western Arctic Ocean As A Testbed, Melissa S. Schwab, Jörg D. Rickli, Robie W. Macdonald, H. Rodger Harvey, Negar Haghipour, Timothy I. Eglinton

OES Faculty Publications

Interactions between organic and detrital mineral phases strongly influence both the dispersal and accumulation of terrestrial organic carbon (OC) in continental margin sediments. Yet the complex interplay among biological, chemical, and physical processes limits our understanding of how organo-mineral interactions evolve during sediment transfer and burial. In particular, diverse OC sources and complex hydrodynamic processes hinder the assessment of how the partnership of organic matter and its mineral host evolves during supply and dispersal over continental margins. In this study, we integrate new and compiled sedimentological (grain size, surface area), organic (%OC, OC-δ13C, OC-F14C), and inorganic …


Seasonal Dispersal Of Fjord Meltwaters As An Important Source Of Iron And Manganese To Coastal Antarctic Phytoplankton, Kiefer O. Forsch, Lisa Hahn-Woernle, Robert M. Sherrell, Vincent J. Roccanova, Kaixuan Bu, David Burdige, Maria Vernet, Katherine A. Barbeau Jan 2021

Seasonal Dispersal Of Fjord Meltwaters As An Important Source Of Iron And Manganese To Coastal Antarctic Phytoplankton, Kiefer O. Forsch, Lisa Hahn-Woernle, Robert M. Sherrell, Vincent J. Roccanova, Kaixuan Bu, David Burdige, Maria Vernet, Katherine A. Barbeau

OES Faculty Publications

Glacial meltwater from the western Antarctic Ice Sheet is hypothesized to be an important source of cryospheric iron, fertilizing the Southern Ocean, yet its trace-metal composition and factors that control its dispersal remain poorly constrained. Here we characterize meltwater iron sources in a heavily glaciated western Antarctic Peninsula (WAP) fjord. Using dissolved and particulate ratios of manganese to iron in meltwaters, porewaters, and seawater, we show that surface glacial melt and subglacial plumes contribute to the seasonal cycle of iron and manganese within a fjord still relatively unaffected by climate-change-induced glacial retreat. Organic ligands derived from the phytoplankton bloom and …


Taxonomic And Nutrient Controls On Phytoplankton Iron Quotas In The Ocean, Benjamin S. Twining, Olga Antipova, P. Dreux Chappell, Natalie R. Cohen, Jeremy E. Jacquot, Elizabeth L. Mann, Adrian Marchetti, Daniel C. Ohnemus, Sara Rauschenberg, Alessandro Tagliabue Jan 2021

Taxonomic And Nutrient Controls On Phytoplankton Iron Quotas In The Ocean, Benjamin S. Twining, Olga Antipova, P. Dreux Chappell, Natalie R. Cohen, Jeremy E. Jacquot, Elizabeth L. Mann, Adrian Marchetti, Daniel C. Ohnemus, Sara Rauschenberg, Alessandro Tagliabue

OES Faculty Publications

Phytoplankton iron contents (i.e., quotas) directly link biogeochemical cycles of iron and carbon and drive patterns of nutrient limitation, recycling, and export. Ocean biogeochemical models typically assume that iron quotas are either static or controlled by dissolved iron availability. We measured iron quotas in phytoplankton communities across nutrient gradients in the Pacific Ocean and found that quotas diverged significantly in taxon‐specific ways from laboratory‐derived predictions. Iron quotas varied 40‐fold across nutrient gradients, and nitrogen‐limitation allowed diatoms to accumulate fivefold more iron than co‐occurring flagellates even under low iron availability. Modeling indicates such “luxury” uptake is common in large regions of …


Salt Marsh Hydrogeology: A Review, Julia Guimond, Joseph Tamborski Jan 2021

Salt Marsh Hydrogeology: A Review, Julia Guimond, Joseph Tamborski

OES Faculty Publications

Groundwater–surface water exchange in salt marsh ecosystems mediates nearshore salt, nutrient, and carbon budgets with implications for biological productivity and global climate. Despite their importance, a synthesis of salt marsh groundwater studies is lacking. In this review, we summarize drivers mediating salt marsh hydrogeology, review field and modeling techniques, and discuss patterns of exchange. New data from a Delaware seepage meter study are reported which highlight small-scale spatial variability in exchange rates. A synthesis of the salt marsh hydrogeology literature reveals a positive relationship between tidal range and submarine groundwater discharge but not porewater exchange, highlighting the multidimensional drivers of …


A Coastal N₂ Fixation Hotspot At The Cape Hatteras Front: Elucidating Spatial Heterogeneity In Diazotroph Activity Via Supervised Machine Learning, Corday R. Selden, P. Dreux Chappell, Sophie Clayton, Alfonso Macías-Tapia, Peter W. Bernhardt, Margaret R. Mulholland Jan 2021

A Coastal N₂ Fixation Hotspot At The Cape Hatteras Front: Elucidating Spatial Heterogeneity In Diazotroph Activity Via Supervised Machine Learning, Corday R. Selden, P. Dreux Chappell, Sophie Clayton, Alfonso Macías-Tapia, Peter W. Bernhardt, Margaret R. Mulholland

OES Faculty Publications

In the North Atlantic Ocean, dinitrogen (N2) fixation on the western continental shelf represents a significant fraction of basin‐wide nitrogen (N) inputs. However, the factors regulating coastal N2 fixation remain poorly understood, in part due to sharp physico‐chemical gradients and dynamic water mass interactions that are difficult to constrain via traditional oceanographic approaches. This study sought to characterize the spatial heterogeneity of N2 fixation on the western North Atlantic shelf, at the confluence of Mid‐ and South Atlantic Bight shelf waters and the Gulf Stream, in August 2016. Rates were quantified using the 15N2 …


Assessment Of Tidal Range Changes In The North Sea From 1958 To 2014, Leon Jänicke, Andra Ebener, Sönke Dangendorf, Arne Arns, Michael Schindelegger, Sebastian Niehüser, Ivan D. Haigh, Philip Woodworth, Jürgen Jensen Jan 2021

Assessment Of Tidal Range Changes In The North Sea From 1958 To 2014, Leon Jänicke, Andra Ebener, Sönke Dangendorf, Arne Arns, Michael Schindelegger, Sebastian Niehüser, Ivan D. Haigh, Philip Woodworth, Jürgen Jensen

CCPO Publications

We document an exceptional large-spatial scale case of changes in tidal range in the North Sea, featuring pronounced trends between -2.3 mm/yr at tide gauges in the United Kingdom and up to 7 mm/yr in the German Bight between 1958 and 2014. These changes are spatially heterogeneous and driven by a superposition of local and large-scale processes within the basin. We use principal component analysis to separate large-scale signals appearing coherently over multiple stations from rather localized changes. We identify two leading principal components (PCs) that explain about 69% of tidal range changes in the entire North Sea including the …


Evaluating The Performance Of National Water Model Snow Simulations In The Northeastern United States Using Advanced Mesonet Observations, Patrick William Naple Jan 2021

Evaluating The Performance Of National Water Model Snow Simulations In The Northeastern United States Using Advanced Mesonet Observations, Patrick William Naple

Legacy Theses & Dissertations (2009 - 2024)

Snow is a critical component in the hydrologic cycle and critical to runoff in many regions. While not as deep or persistent as snow in the Western United States (WUS) , snow in the Northeastern US (NEUS) is critical to water resource management and flood forecasting. For hydrological applications, snow is simulated using coupled hydrology models . These models couple numerical weather models, land surface models, and channel routing models that simulate water transport. One such coupled hydrology model is the NOAA National Water Model (NWM), implemented in 2016. The NWM runs a specific configuration of the WRF-Hydro community model. …


Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow Jan 2021

Pesticide Occurrence And Persistence Entering Recreational Lakes In Watersheds Of Varying Land Uses, Jessica Satiroff, Tiffany Messer, Aaron R. Mittelstet, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Currently little is known of newer pesticide classes and their occurrence and persistence in recreational lakes. Therefore, the objectives of this study were to (1) assess average pesticide concentrations and loadings entering recreational lakes in three mixed land use watersheds throughout the growing season, (2) evaluate pesticide persistence longitudinally within the lakes, and (3) perform an ecotoxicity assessment. Six sampling campaigns were conducted at three lakes from April through October 2018 to measure the occurrence and persistence during pre, middle, and post growing season. Polar organic chemical integrative samplers (POCIS) were placed in streams near lake inlets and monthly samples …


Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow Jan 2021

Occurrence Of Arsenite In Surface And Groundwater Associated With A Perennial Stream Located In Western Nebraska, Usa, Arindam Malakar, Rajesh Singh, Jeffrey Westrop, Karrie A. Weber, Christopher N. Elofson, Manish Kumar, Daniel D. Snow

Nebraska Water Center: Faculty Publications

Dissolved arsenic typically results from chemical weathering of arsenic rich sediments and is most often found in oxidized forms in surface water. The mobility of arsenic is controlled by its valence state and also by its association with iron oxides minerals, the forms of which are both influenced by abiotic and biotic processes in aqueous environment. In this study, speciation methods were used to measure and confirm the presence of reduced arsenic species in the surface water of Frenchman creek, a gaining stream that crosses the Colorado- Nebraska border. Selective extraction analysis of aquifer and stream bed sediments shows that …


Droughtscape, Winter 2021, National Drought Mitigation Center Jan 2021

Droughtscape, Winter 2021, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

DroughtScape, Winter 2021


Carbonaceous Matter In The Atmosphere And Glaciers Of The Himalayas And The Tibetan Plateau: An Investigative Review, Chaoliu Li, Fangping Yan, Shichang Kang, Caiqing Yan, Zhaofu Hu, Pengfei Chen, Shaopeng Gao, Chao Zhang, Cenlin He, Susan Kaspari, Aron Stubbins Jan 2021

Carbonaceous Matter In The Atmosphere And Glaciers Of The Himalayas And The Tibetan Plateau: An Investigative Review, Chaoliu Li, Fangping Yan, Shichang Kang, Caiqing Yan, Zhaofu Hu, Pengfei Chen, Shaopeng Gao, Chao Zhang, Cenlin He, Susan Kaspari, Aron Stubbins

Geological Sciences Faculty Scholarship

Carbonaceous matter, including organic carbon (OC) and black carbon (BC), is an important climate forcing agent and contributes to glacier retreat in the Himalayas and the Tibetan Plateau (HTP). The HTP – the so-called “Third Pole” – contains the most extensive glacial area outside of the polar regions. Considerable research on carbonaceous matter in the HTP has been conducted, although this research has been challenging due to the complex terrain and strong spatiotemporal heterogeneity of carbonaceous matter in the HTP. A comprehensive investigation of published atmospheric and snow data for HTP carbonaceous matter concentration, deposition and light absorption is presented, …


Influence Of Iceberg-Discharge Events On The Climate And Circulation Of The Central North Atlantic Ocean During The Last Glaciation, Ava Mcilvaine Jan 2021

Influence Of Iceberg-Discharge Events On The Climate And Circulation Of The Central North Atlantic Ocean During The Last Glaciation, Ava Mcilvaine

Scripps Senior Theses

The repeated occurrence of episodic iceberg-discharge events and abrupt climate change in the North Atlantic Ocean is well-documented for the late Quaternary period. However, much of the evidence for these periods known as Heinrich Events comes from the subpolar region, where deposition can be dominated by ice-rafted debris (IRD) and overwhelm other oceanographic and climatic indicators. Thus, the following analysis of coarse sediment from Integrated Ocean Drilling Program (IODP) Core Site U1313 (41°0.0'N, 32°57.42'W) evaluated ocean cooling related to ice-rafting, water mass migration, and climate change over the approximate last 100,000 years. Site U1313 is located near the North Atlantic …


Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li Jan 2021

Effects Of Hydrological And Climatic Variables On Cyanobacterial Blooms In Four Large Shallow Lakes Fed By The Yangtze River, Jian Huang, Qiujin Xu, Xixi Wang, Hao Ji, Edward J. Quigley, Mohamadali Sharbatmaleki, Simeng Li, Beidou Xi, Biao Sun, Caole Li

Civil & Environmental Engineering Faculty Publications

Shallow lakes, one of the most widespread water bodies in the world, are easily shifted to a new trophic state due to external interferences. Shifting hydrologic conditions and climate change can cause cyanobacterial harmful algal blooms (CyanoHABs) in shallow lakes, which pose serious threats to ecological integrity and human health. This study analyzed the effects of hydrologic and meteorological variables on cyanobacterial blooms in Yangtze-connected lakes (Lake Dongting and Poyang) and isolated lakes (Lake Chao and Tai). The results show that (i) chlorophyll-a (Chl-a) concentration tends to decrease exponentially with increasing relative lake level fluctuations (RLLF) and precipitation, but to …


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 …


Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue Jan 2021

Wave Climate Associated With Changing Water Level And Ice Cover In Lake Michigan, Chenfu Huang, Longhuan Zhu, Gangfeng Ma, Guy A. Meadows, Pengfei Xue

Civil & Environmental Engineering Faculty Publications

Detailed knowledge of wave climate change is essential for understanding coastal geomorphological processes, ecosystem resilience, the design of offshore and coastal engineering structures and aquaculture systems. In Lake Michigan, the in-situ wave observations suitable for long-term analysis are limited to two offshore MetOcean buoys. Since this distribution is inadequate to fully represent spatial patterns of wave climate across the lake, a series of high-resolution SWAN model simulations were performed for the analysis of long-term wave climate change for the entirety of Lake Michigan from 1979 to 2020. Model results were validated against observations from two offshore buoys and 16 coastal …


Anticipating And Adapting To The Future Impacts Of Climate Change On The Health, Security And Welfare Of Low Elevation Coastal Zone (Lecz) Communities In Southeastern Usa, Thomas Allen, Joshua Behr, Anamaria Bukvic, Ryan S.D. Calder, Kiki Caruson, Charles Connor, Christopher D'Elia, David Dismukes, Robin Ersing, Rima Franklin, Jesse Goldstein, Jonathon Goodall, Scott Hemmerling, Jennifer Irish, Steven Lazarus, Derek Loftis, Mark Luther, Leigh Mccallister, Karen Mcglathery, Molly Mitchell, William Moore, Charles Reid Nichols, Karinna Nunez, Matthew Reidenbach, Julie Shortridge, Robert Weisberg, Robert Weiss, Lynn Donelson Wright, Meng Xia, Kehui Xu, Donald Young, Gary Zarillo, Julie C. Zinnert Jan 2021

Anticipating And Adapting To The Future Impacts Of Climate Change On The Health, Security And Welfare Of Low Elevation Coastal Zone (Lecz) Communities In Southeastern Usa, Thomas Allen, Joshua Behr, Anamaria Bukvic, Ryan S.D. Calder, Kiki Caruson, Charles Connor, Christopher D'Elia, David Dismukes, Robin Ersing, Rima Franklin, Jesse Goldstein, Jonathon Goodall, Scott Hemmerling, Jennifer Irish, Steven Lazarus, Derek Loftis, Mark Luther, Leigh Mccallister, Karen Mcglathery, Molly Mitchell, William Moore, Charles Reid Nichols, Karinna Nunez, Matthew Reidenbach, Julie Shortridge, Robert Weisberg, Robert Weiss, Lynn Donelson Wright, Meng Xia, Kehui Xu, Donald Young, Gary Zarillo, Julie C. Zinnert

Political Science & Geography Faculty Publications

Low elevation coastal zones (LECZ) are extensive throughout the southeastern United States. LECZ communities are threatened by inundation from sea level rise, storm surge, wetland degradation, land subsidence, and hydrological flooding. Communication among scientists, stakeholders, policy makers and minority and poor residents must improve. We must predict processes spanning the ecological, physical, social, and health sciences. Communities need to address linkages of (1) human and socioeconomic vulnerabilities; (2) public health and safety; (3) economic concerns; (4) land loss; (5) wetland threats; and (6) coastal inundation. Essential capabilities must include a network to assemble and distribute data and model code to …


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

National 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 …


The Rise And Fall Of Wiñaymarka: Rethinking Cultural And Environmental Interactions In The Southern Basin Of Lake Titicaca, Maria C. Bruno, José M. Capriles, Christine A. Hastorf, Sherilyn C. Fritz, D. Marie Weide, Alejandra I. Domic, Paul A. Baker Jan 2021

The Rise And Fall Of Wiñaymarka: Rethinking Cultural And Environmental Interactions In The Southern Basin Of Lake Titicaca, Maria C. Bruno, José M. Capriles, Christine A. Hastorf, Sherilyn C. Fritz, D. Marie Weide, Alejandra I. Domic, Paul A. Baker

Department of Earth and Atmospheric Sciences: Faculty Publications

Investigations of how past human societies managed during times of major climate change can inform our understanding of potential human responses to ongoing environmental change. In this study, we evaluate the impact of environmental variation on human communities over the last four millennia in the southern Lake Titicaca basin of the Andes, known as Lake Wiñaymarka. Refined paleoenvironmental reconstructions from new diatom-based reconstructions of lake level together with archaeological evidence of animal and plant resource use from sites on the Taraco Peninsula, Bolivia, reveal frequent climate and lake-level changes within major cultural phases. We posit that climate fluctuations alone do …