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Department of Earth and Atmospheric Sciences: Faculty Publications

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Articles 31 - 60 of 670

Full-Text Articles in Earth Sciences

Cloud Radiative Effects On Mjo Development In Dynamo, Qi Hu, Zihang Han, Shuguang Wang Jan 2022

Cloud Radiative Effects On Mjo Development In Dynamo, Qi Hu, Zihang Han, Shuguang Wang

Department of Earth and Atmospheric Sciences: Faculty Publications

Observed Madden–Julian oscillation (MJO) events are examined with the aid of regional model simulations to understand the role of cloud radiative effects in the MJO development. The importance of this role is demonstrated by the absence of the MJO in the model simulations that contain no cloud radiative effects. Comparisons of model simulations with and without the cloud radiative effects and observation help identify the major processes arising from those effects. Those processes develop essentially from heating in the upper troposphere due to shortwave absorption within anvil clouds in the upper troposphere and the convergence of longwave radiation in the …

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Recent Advances Toward Transparent Methane Emissions Monitoring: A Review, Broghan M. Erland, Andrew K. Thorpe, John Gamon Jan 2022

Recent Advances Toward Transparent Methane Emissions Monitoring: A Review, Broghan M. Erland, Andrew K. Thorpe, John Gamon

Department of Earth and Atmospheric Sciences: Faculty Publications

Given that anthropogenic greenhouse gas (GHG) emissions must be immediately reduced to avoid drastic increases in global temperature, methane emissions have been placed center stage in the fight against climate change. Methane has a significantly larger warming potential than carbon dioxide. A large percentage of methane emissions are in the form of industry emissions, some of which can now be readily identified and mitigated. This review considers recent advances in methane detection that allow accurate and transparent monitoring, which are needed for reducing uncertainty in source attribution and evaluating progress in emissions reductions. A particular focus is on complementary methods …

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Late Cretaceous Paleoceanographic Evolution And The Onset Of Cooling In The Santonian At Southern High Latitudes (Iodp Site U1513, Se Indian Ocean), Maria Rose Petrizzo, Kenneth G. Macleod, David K. Watkins, Erik Wolfgring, Brian T. Huber Dec 2021

Late Cretaceous Paleoceanographic Evolution And The Onset Of Cooling In The Santonian At Southern High Latitudes (Iodp Site U1513, Se Indian Ocean), Maria Rose Petrizzo, Kenneth G. Macleod, David K. Watkins, Erik Wolfgring, Brian T. Huber

Department of Earth and Atmospheric Sciences: Faculty Publications

The latest Cenomanian to Santonian sedimentary record recovered at IODP Expedition 369 Site U1513 in the Mentelle Basin (SE Indian Ocean, paleolatitude 60°S at 85 Ma) is studied to interpret the paleoceanographic evolution in the Southern Hemisphere. The planktonic foraminiferal assemblage changes, the depth ecology preferences of different species, and the surface and seafloor temperature inferred from the stable isotopic values measured on foraminiferal tests provide meaningful information to the understanding of the Late Cretaceous climate. The hothouse climate during the Turonian-Santonian, characterized by weak latitudinal temperature gradients and high atmospheric CO2 concentrations, is followed by a progressive cooling …

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Moisture Transport Associated With Southwest Monsoon Rainfall Over Sri Lanka In Relatively Wet And Dry Rainfall Years, Sherly Shelton Nov 2021

Moisture Transport Associated With Southwest Monsoon Rainfall Over Sri Lanka In Relatively Wet And Dry Rainfall Years, Sherly Shelton

Department of Earth and Atmospheric Sciences: Faculty Publications

Atmospheric moisture transportation associated with the occurrence of relatively wet and dry southwest monsoon (SWM) years over Sri Lanka is still not fully understood. This study focused on investigating the role of moisture transport in contrast SWM years. We selected seven wet (SWMWet) and nine dry (SWMDry) years for 1985-2015 and found that the whole country experiences above-average (below average) rainfall in SWMWet (SWMDry) years. In SWMWet years, strengthening moisture-laden low-level jets (LLJ) from the Arabian Sea bring a large amount of moisture towards Sri Lanka. In contrast, the weakening of the …

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Multi-Proxy Record Of Holocene Paleoenvironmental Conditions From Yellowstone Lake, Wyoming, Usa, Sabrina R. Brown, Rosine Cartier, Christopher M. Schiller, Petra Zahajská, Sherilyn C. Fritz, Lisa A. Morgan, Cathy Whitlock, Daniel J. Conley, Jack H. Lacey, Melanie J. Leng, W.C. Pat Shanks Iii Nov 2021

Multi-Proxy Record Of Holocene Paleoenvironmental Conditions From Yellowstone Lake, Wyoming, Usa, Sabrina R. Brown, Rosine Cartier, Christopher M. Schiller, Petra Zahajská, Sherilyn C. Fritz, Lisa A. Morgan, Cathy Whitlock, Daniel J. Conley, Jack H. Lacey, Melanie J. Leng, W.C. Pat Shanks Iii

Department of Earth and Atmospheric Sciences: Faculty Publications

A composite 11.82 m-long (9876e-67 cal yr BP) sediment record from Yellowstone Lake, Wyoming was analyzed using a robust set of biological and geochemical proxies to investigate the paleoenvironmental evolution of the lake and its catchment in response to long-term climate forcing. Oxygen isotopes from diatom frustules were analyzed to reconstruct Holocene climate changes, and pollen, charcoal, diatom assemblages, and biogenic silica provided information on terrestrial and limnological responses. The long-term trends recorded in the terrestrial and limnic ecosystems over the last 9800 years reflect the influence of changes in the amplification of the seasonal cycle of insolation on regional …

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Lethal Microbial Blooms Delayed Freshwater Ecosystem Recovery Following The End-Permian Extinction, Chris Mays, Stephen Mcloughlin, Tracy D. Frank, Christopher R. Fielding, Sam M. Slater, Vivi Vajda Sep 2021

Lethal Microbial Blooms Delayed Freshwater Ecosystem Recovery Following The End-Permian Extinction, Chris Mays, Stephen Mcloughlin, Tracy D. Frank, Christopher R. Fielding, Sam M. Slater, Vivi Vajda

Department of Earth and Atmospheric Sciences: Faculty Publications

Harmful algal and bacterial blooms linked to deforestation, soil loss and global warming are increasingly frequent in lakes and rivers. We demonstrate that climate changes and deforestation can drive recurrent microbial blooms, inhibiting the recovery of freshwater ecosystems for hundreds of millennia. From the stratigraphic successions of the Sydney Basin, Australia, our fossil, sedimentary and geochemical data reveal bloom events following forest ecosystem collapse during the most severe mass extinction in Earth’s history, the end- Permian event (EPE; c. 252.2 Ma). Microbial communities proliferated in lowland fresh and brackish waterbodies, with algal concentrations typical of modern blooms. These initiated before …

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Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta Sep 2021

Prediction Of Biome-Specific Potential Evapotranspiration In Mongolia Under A Scarcity Of Weather Data, Khulan Batsukh, Vitaly A. Zlotnik, Andrew E. Suyker, Paolo Nasta

Department of Earth and Atmospheric Sciences: Faculty Publications

We propose practical guidelines to predict biome-specific potential evapotranspiration (ETp) from the knowledge of grass-reference evapotranspiration (ET0) and a crop coefficient (Kc) in Mongolia. A paucity of land-based weather data hampers use of the Penman–Monteith equation (FAO-56 PM) based on the Food and Agriculture Organization (FAO) guidelines to predict daily ET0. We found that the application of the Hargreaves equation provides ET0 estimates very similar to those from the FAO-56 PM approach. The Kc value is tabulated only for crops in the FAO-56 guidelines but is unavailable …

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New Insights Into The Drainage Of Inundated Ice-Wedge Polygons Using Fundamental Hydrologic Principles, Dylan R. Harp, Vitaly A. Zlotnik, Charles J. Abolt, Bob Busey3, Sofia T. Avendaño, Brent D. Newman, Adam L. Atchley, Elchin Jafarov, Cathy J. Wilson, Katrina E. Bennett Aug 2021

New Insights Into The Drainage Of Inundated Ice-Wedge Polygons Using Fundamental Hydrologic Principles, Dylan R. Harp, Vitaly A. Zlotnik, Charles J. Abolt, Bob Busey3, Sofia T. Avendaño, Brent D. Newman, Adam L. Atchley, Elchin Jafarov, Cathy J. Wilson, Katrina E. Bennett

Department of Earth and Atmospheric Sciences: Faculty Publications

The pathways and timing of drainage from the inundated centers of ice-wedge polygons in a warming climate have important implications for carbon flushing, advective heat transport, and transitions from methane to carbon dioxide dominated emissions. Here, we expand on previous research using a recently developed analytical model of drainage from a low-centered polygon. Specifically, we perform (1) a calibration to field data identifying necessary model refinements and (2) a rigorous model sensitivity analysis that expands on previously published indications of polygon drainage characteristics. This research provides intuition on inundated polygon drainage by presenting the first in-depth analysis of drainage within …

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Dynamical Variations Of The Global Covid-19 Pandemic Based On A Seicr Disease Model: A New Approach Of Yi Hua Jie Mu, Xia Wang, Gang Yin, Zengyun Hu, Daihai He, Qianqian Cui, Xiaomei Feng, Zhidong Teng, Qi Hu, Jiansen Li, Qiming Zhou Jul 2021

Dynamical Variations Of The Global Covid-19 Pandemic Based On A Seicr Disease Model: A New Approach Of Yi Hua Jie Mu, Xia Wang, Gang Yin, Zengyun Hu, Daihai He, Qianqian Cui, Xiaomei Feng, Zhidong Teng, Qi Hu, Jiansen Li, Qiming Zhou

Department of Earth and Atmospheric Sciences: Faculty Publications

The ongoing coronavirus disease 2019 (COVID-19) pandemic has caused more than 150 million cases of infection to date and poses a serious threat to global public health. In this study, global COVID-19 data were used to examine the dynamical variations from the perspectives of immunity and contact of 84 countries across the five climate regions: tropical, arid, temperate, and cold. A new approach named Yi Hua Jie Mu is proposed to obtain the transmission rates based on the COVID-19 data between the countries with the same climate region over the Northern Hemisphere and Southern Hemisphere. Our results suggest that the …

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Pyusercalc: A Revised Jupyter Notebook Calculator For Uranium-Series Disequilibria In Basalts, Lynne J. Elkins, Marc Spiegelman Jun 2021

Pyusercalc: A Revised Jupyter Notebook Calculator For Uranium-Series Disequilibria In Basalts, Lynne J. Elkins, Marc Spiegelman

Department of Earth and Atmospheric Sciences: Faculty Publications

Meaningful analysis of uranium-series isotopic disequilibria in basaltic lavas relies on the use of complex forward numerical models like dynamic melting (McKenzie, 1985, https://doi.org/10.1016/0012- 821x(85)90001-9) and equilibrium porous flow (Spiegelman & Elliott, 1993, https://doi.org/10.1016/0012- 821x(93)90155-3). Historically, such models have either been solved analytically for simplified scenarios, such as constant melting rate or constant solid/melt trace element partitioning throughout the melting process, or have relied on incremental or numerical calculators with limited power to solve problems and/or restricted availability. The most public numerical solution to reactive porous flow, UserCalc (Spiegelman, 2000, https:// doi.org/10.1029/1999gc000030) was maintained on a private institutional server for …

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Polarimetric Radar Characteristics Of Tornadogenesis Failure In Supercell Thunderstorms, Matthew S. Van Den Broeke Apr 2021

Polarimetric Radar Characteristics Of Tornadogenesis Failure In Supercell Thunderstorms, Matthew S. Van Den Broeke

Department of Earth and Atmospheric Sciences: Faculty Publications

Many nontornadic supercell storms have times when they appear to be moving toward tornadogenesis, including the development of a strong low-level vortex, but never end up producing a tornado. These tornadogenesis failure (TGF) episodes can be a substantial challenge to operational meteorologists. In this study, a sample of 32 pre-tornadic and 36 pre-TGF supercells is examined in the 30 min pre-tornadogenesis or pre-TGF period to explore the feasibility of using polarimetric radar metrics to highlight storms with larger tornadogenesis potential in the near-term. Overall the results indicate few strong distinguishers of pre-tornadic storms. Differential reflectivity (ZDR) arc size …

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A Multiproxy Database Of Western North American Holocene Paleoclimate Records, Cody Routson, Darrell S. Kaufman, Nicholas P. Mckay, Michael P. Erb, Stephanie H. Arcusa, Kendrick J. Brown, Matthew E. Kirby, Jeremiah P. Marsicek, R Scott Anderson, Gonzalo Jimenez-Moreno, Jessica R. Rodysill, Matthew S. Lachniet, Sherilyn C. Fritz, Joseph R. Bennett, Michelle F. Goman, Sarah E. Metcalfe, Jennifer M. Galloway, Gerrit Schoups, David B. Wahl, Jesse L. Morris, Francisca Staines-Urias, Andria Dawson, Bryan N. Shuman, Daniel G. Gavin, Jeffrey S. Munroe, Brian F. Cumming Apr 2021

A Multiproxy Database Of Western North American Holocene Paleoclimate Records, Cody Routson, Darrell S. Kaufman, Nicholas P. Mckay, Michael P. Erb, Stephanie H. Arcusa, Kendrick J. Brown, Matthew E. Kirby, Jeremiah P. Marsicek, R Scott Anderson, Gonzalo Jimenez-Moreno, Jessica R. Rodysill, Matthew S. Lachniet, Sherilyn C. Fritz, Joseph R. Bennett, Michelle F. Goman, Sarah E. Metcalfe, Jennifer M. Galloway, Gerrit Schoups, David B. Wahl, Jesse L. Morris, Francisca Staines-Urias, Andria Dawson, Bryan N. Shuman, Daniel G. Gavin, Jeffrey S. Munroe, Brian F. Cumming

Department of Earth and Atmospheric Sciences: Faculty Publications

Holocene climate reconstructions are useful for understanding the diverse features and spatial heterogeneity of past and future climate change. Here we present a database of western North American Holocene paleoclimate records. The database gathers paleoclimate time series from 184 terrestrial and marine sites, including 381 individual proxy records. The records span at least 4000 of the last 12 000 years (median duration of 10 725 years) and have been screened for resolution, chronologic control, and climate sensitivity. Records were included that reflect temperature, hydroclimate, or circulation features. The database is shared in the machine readable Linked Paleo Data (LiPD) format …

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Modern Silicon Dynamics Of A Small High-Latitude Subarctic Lake, Petra Zahajska, Carolina Olid, Johanna Stadmark, Sherilyn C. Fritz, Sophie Opfergelt, Daniel J. Conley Apr 2021

Modern Silicon Dynamics Of A Small High-Latitude Subarctic Lake, Petra Zahajska, Carolina Olid, Johanna Stadmark, Sherilyn C. Fritz, Sophie Opfergelt, Daniel J. Conley

Department of Earth and Atmospheric Sciences: Faculty Publications

High biogenic silica (BSi) concentrations occur sporadically in lake sediments throughout the world; however, the processes leading to high BSi concentrations vary. We explored the factors responsible for the high BSi concentration in sediments of a small, high-latitude subarctic lake (Lake 850). The Si budget of this lake had not been fully characterized before to establish the drivers of BSi accumulation in this environment. To do this, we combined measurements of variations in stream discharge, dissolved silica (DSi) concentrations, and stable Si isotopes in both lake and stream water with measurements of BSi content in lake sediments. Water, radon, and …

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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 …

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Lift In The Vertical Shear Of Southerly Jet Embedded In A Uniform Westerly Flow, Qi Hu, George Limpert Jan 2021

Lift In The Vertical Shear Of Southerly Jet Embedded In A Uniform Westerly Flow, Qi Hu, George Limpert

Department of Earth and Atmospheric Sciences: Faculty Publications

A new mechanism is proposed as a potential cause for the one-third of warm season severe nocturnal convection in the U.S. Great Plains that develops in environments without the presence of air mass boundaries of fronts or mesoscale systems. This mechanism is tested in two- and three dimensional models. Results show strong ascent (~1.0 m/s) sufficient for nocturnal convection initiation, arising from interactions of mean westerly zonal wind with the vertical shear of a northern vortex and also perturbation westerly winds that are created by the Coriolis torque on the Great Plains southerly low-level jet. The interaction involving the northern …

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Subsurface Structures Along Western Yucatan From Integrated Geophysical Analysis, Irina Filina, Lucas Hartford Jan 2021

Subsurface Structures Along Western Yucatan From Integrated Geophysical Analysis, Irina Filina, Lucas Hartford

Department of Earth and Atmospheric Sciences: Faculty Publications

Integration of seismic, gravity, and magnetic data revealed variations in crustal architecture along the Yucatan passive continental margin. The crust beneath the Yucatan salt basin is ~10 km thick and is primarily a lower continental crust. In contrast, the crust beneath the Campeche salt basin is thicker and comprises both the upper and the lower crustal layers. These variations in crustal architecture explain the strikingly different tectonic histories of these basins outlined by previous authors. The rifting of the Yucatan margin was associated with extensive magmatism expressed as voluminous igneous intrusions in the lower crust, one of which is manifested …

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Measurements From Mobile Surface Vehicles During The Lower Atmospheric Profiling Studies At Elevation – A Remotely-Piloted Aircraft Team Experiment (Lapse-Rate), Gijs De Boer, Sean Waugh, Alexander Erwin, Steve Borenstein, Cory Dixon, Wafa’A Shanti, Adam Houston, Brian Argrow Jan 2021

Measurements From Mobile Surface Vehicles During The Lower Atmospheric Profiling Studies At Elevation – A Remotely-Piloted Aircraft Team Experiment (Lapse-Rate), Gijs De Boer, Sean Waugh, Alexander Erwin, Steve Borenstein, Cory Dixon, Wafa’A Shanti, Adam Houston, Brian Argrow

Department of Earth and Atmospheric Sciences: Faculty Publications

Between 14 and 20 July 2018, small unmanned aircraft systems (UASs) were deployed to the San Luis Valley of Colorado (USA) alongside surface-based remote sensors, in situ sensors, and radiosonde sys- tems as part of the Lower Atmospheric Profiling Studies at Elevation – a Remotely-piloted Aircraft Team Ex- periment (LAPSE-RATE). The measurements collected as part of LAPSE-RATE targeted quantities related to enhancing our understanding of boundary layer structure, cloud and aerosol properties and surface–atmosphere exchange and provide detailed information to support model evaluation and improvement work. Additionally, intensive intercomparison between the different unmanned aircraft platforms was completed. The current pa- …

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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 …

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Age And Paleoenvironmental Significance Of The Frazer Beach Member—A New Lithostratigraphic Unit Overlying The End-Permian Extinction Horizon In The Sydney Basin, Australia, Stephen Mcloughlin, Robert S. Nicoll, James L. Crowley, Vivi Vajda, Chris Mays, Christopher R. Fielding, Tracy D. Frank, Alexander Wheeler, Malcolm Bocking Jan 2021

Age And Paleoenvironmental Significance Of The Frazer Beach Member—A New Lithostratigraphic Unit Overlying The End-Permian Extinction Horizon In The Sydney Basin, Australia, Stephen Mcloughlin, Robert S. Nicoll, James L. Crowley, Vivi Vajda, Chris Mays, Christopher R. Fielding, Tracy D. Frank, Alexander Wheeler, Malcolm Bocking

Department of Earth and Atmospheric Sciences: Faculty Publications

The newly defined Frazer Beach Member of the Moon Island Beach Formation is identified widely across the Sydney Basin in both outcrop and exploration wells. This thin unit was deposited immediately after extinction of the Glossopteris flora (defining the terrestrial end- Permian extinction event). The unit rests conformably on the uppermost Permian coal seam in most places. A distinctive granule-microbreccia bed is locally represented at the base of the member. The unit otherwise consists of dark gray to black siltstone, shale, mudstone and, locally, thin lenses of fine-grained sandstone and tuff. The member represents the topmost unit of the Newcastle …

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Predicting College Students’ Future Intentions To Engage In Public-Sphere Water Conservation Behaviors, Austin Wise, Donald Johnson, George Wardlow, Kathi Jogan Jan 2021

Predicting College Students’ Future Intentions To Engage In Public-Sphere Water Conservation Behaviors, Austin Wise, Donald Johnson, George Wardlow, Kathi Jogan

Department of Earth and Atmospheric Sciences: Faculty Publications

The purpose of this study was to describe selected college students’ (N = 252) perceptions of and future intentions (FI) to engage in public-sphere water conservation behaviors, and to determine if FI could be predicted by a single or linear combination of student demographic characteristics and latent variables. A majority of respondents agreed a growing population will negatively affect water quantity (90.5%) and there is a need for water resource management (85.6%). A majority disagreed or strongly disagreed that they (53.4%), their family (57.1%), or their friends (67.5%) practiced water conservation, or that people in their hometowns were concerned about …

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Influence Of Irrigation Drivers Using Boosted Regression Trees: Kansas High Plains, Susan E. Lamb, Erin M.K. Haacker, Samuel J. Smidt Jan 2021

Influence Of Irrigation Drivers Using Boosted Regression Trees: Kansas High Plains, Susan E. Lamb, Erin M.K. Haacker, Samuel J. Smidt

Department of Earth and Atmospheric Sciences: Faculty Publications

Groundwater levels across parts of western Kansas have been declining at unsustainable rates due to pumping for agricultural irrigation despite water-saving efforts. Accelerating this decline is the complex agricultural landscape, consisting of both categorical (e.g., management boundaries) and numerical (e.g., crop prices) factors that drive irrigation decisions, making integrated water budget management a challenge. Furthermore, these factors frequently change through time, rendering management strategies outdated within relatively short time scales. This study uses boosted regression trees to simultaneously analyze categorical and numerical data against annual irrigation pumping to determine the relative influence of each factor on groundwater pumping across both …

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Opening Of The Gulf Of Mexico: What We Know, What Questions Remain, And How We Might Answer Them, Irina Filina, James Austin, Tony Doré, Elizabeth Johnson, Daniel Minguez, Ian Norton, John Snedden, Robert J. Stern Jan 2021

Opening Of The Gulf Of Mexico: What We Know, What Questions Remain, And How We Might Answer Them, Irina Filina, James Austin, Tony Doré, Elizabeth Johnson, Daniel Minguez, Ian Norton, John Snedden, Robert J. Stern

Department of Earth and Atmospheric Sciences: Faculty Publications

The Gulf of Mexico is an economically important basin with more than a century-long history of hydrocarbon exploration. However, the opening history of the basin remains debated for two reasons: 1) the quality of data does not allow for reliable interpretations of crustal features beneath thick and complex overburden, and 2) most industry well and geophysical data are proprietary. The last concerted effort by industry and academia to summarize the state of knowledge regarding the Gulf of Mexico’s formation was three decades ago and resulted in publication of a major volume as part of the Decade of North American Geology …

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Estimating The Age And Mechanism Of Boulder Transport Related With Extreme Waves Using Lichenometry, Maria A. Oliveira, Esteve Llop, César Andrade, Cristina Branquinho, Ronald Goble, Sónia Queiroz, Maria C. Freitas, Pedro Pinho Dec 2020

Estimating The Age And Mechanism Of Boulder Transport Related With Extreme Waves Using Lichenometry, Maria A. Oliveira, Esteve Llop, César Andrade, Cristina Branquinho, Ronald Goble, Sónia Queiroz, Maria C. Freitas, Pedro Pinho

Department of Earth and Atmospheric Sciences: Faculty Publications

Tsunamis and storms cause considerable coastal flooding, numerous fatalities, destruction of structures, and erosion. The characterization of energy and frequency associated with each wave contribute to the risk assessment in coastal regions. Coastal boulder deposits represent a physical proof of extreme inundation and allow us to study the effects of marine floods further back in time than instrumental and historical records. Age estimation of these deposits is challenging due to lack of materials (such as sand, shells, corals, or organic matter) that retain information about the passage of time. Lichenometry, a simple age estimation method, which is cost effective, quick …

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Introduction To Special Section: Integrated Geophysical Imaging, Irina Filina, Rao Yalamanchili, Simone Re, Daniele Colombo, Antony Price, Vsevolod Egorov, Guimin Liu Nov 2020

Introduction To Special Section: Integrated Geophysical Imaging, Irina Filina, Rao Yalamanchili, Simone Re, Daniele Colombo, Antony Price, Vsevolod Egorov, Guimin Liu

Department of Earth and Atmospheric Sciences: Faculty Publications

This special section illustrates the value of integration with nonseismic geophysical methods, namely potential fields (gravity and magnetics) and electric and electromagnetic techniques. The primary objective is to overcome the overall underappreciation of these methods as exploration tools. We provide their brief overview and present nine case studies illustrating how the integrative approach to geophysical data analysis influences the overall result and reduces the uncertainty of the derived solution.

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Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty Jul 2020

Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty

Department of Earth and Atmospheric Sciences: Faculty Publications

The widespread occurrence of lower Eocene chert and porcellanite has been viewed as a major paleoceanographic issue since the advent of ocean drilling, and both biotic and abiotic forcings have been proposed to explain it. We present a reconstruction of indurated siliceous sediment (ISS) and preserved biosiliceous sediment (PBS) occurrences in the Atlantic Ocean through the Paleocene and Eocene (~66 through 34 Ma). ISS and PBS distributions reveal dissimilar temporal trends, with the peak of ISS occurrences coinciding with the Early Eocene Climatic Optimum, in line with previous studies. PBS occurrences show a generally increasing trend culminating between 44 and …

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Late Cretaceous Stratigraphy And Paleoceanographic Evolution In The Great Australian Bight Basin Based On Results From Iodp Site U1512, K. G. Macleod, Lloyd T. White, Carmine C. Wainman, Mathieu Martinez, Matthew M. Jones, Sietske J. Batenburg, Laurent Riquier, Shannon J. Haynes, David K. Watkins, K. A. Bogus, H.-J. Brumsack, R. Do Monte Guerra, Kirsty M. Edgar, Trine Edvardsen, Dennis Harry, Takashi Hasegawa, R. W. Hobbs, Brian T. Huber, T. Jiang, J. Kuroda, E. Y. Lee, Yong-Xiang Li, Alessandro Maritatai, Lauren K. O'Connor, Maria Rose Petrizzo, Tracy M. Quan, C. Richter, Maria Luisa Garcia Tejada, G. Tagliaro, Erik Wolfgring, Zhaokai Xu Feb 2020

Late Cretaceous Stratigraphy And Paleoceanographic Evolution In The Great Australian Bight Basin Based On Results From Iodp Site U1512, K. G. Macleod, Lloyd T. White, Carmine C. Wainman, Mathieu Martinez, Matthew M. Jones, Sietske J. Batenburg, Laurent Riquier, Shannon J. Haynes, David K. Watkins, K. A. Bogus, H.-J. Brumsack, R. Do Monte Guerra, Kirsty M. Edgar, Trine Edvardsen, Dennis Harry, Takashi Hasegawa, R. W. Hobbs, Brian T. Huber, T. Jiang, J. Kuroda, E. Y. Lee, Yong-Xiang Li, Alessandro Maritatai, Lauren K. O'Connor, Maria Rose Petrizzo, Tracy M. Quan, C. Richter, Maria Luisa Garcia Tejada, G. Tagliaro, Erik Wolfgring, Zhaokai Xu

Department of Earth and Atmospheric Sciences: Faculty Publications

The Upper Cretaceous sedimentary sequence at International Ocean Discovery Program Site U1512 in the Ceduna Sub-basin of the Great Australian Bight represents a continuous, N 690 m thick interval of black silty clay and claystone spanning the lower Turonian through Lower Campanian (~10 million years). Sediments were deposited in an elongate, ~E-W oriented, ~2500 km long rift system that developed between Australia and Antarctica with an open-ocean connection to the west and a continental bridge to the east. Site U1512 cores provide a unique, continuous record of Late Cretaceous deposition in the Ceduna Sub-basin on the hanging wall of the …

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Evidence Of Ridge Propagation In The Eastern Gulf Of Mexico From Integrated Analysis Of Potential Fields And Seismic Data, Irina Filina, Mei Liu, Erin Beutel Jan 2020

Evidence Of Ridge Propagation In The Eastern Gulf Of Mexico From Integrated Analysis Of Potential Fields And Seismic Data, Irina Filina, Mei Liu, Erin Beutel

Department of Earth and Atmospheric Sciences: Faculty Publications

Integrated analysis of gravity, magnetic, and seismic data reveals two phases of spreading in the eastern Gulf of Mexico (GOM) including two distinct spreading centers, suggesting a major ridge reorganization during the opening of the eastern part of the GOM. Ridge propagation between the two spreading episodes explains the following observations: (1) the drastic asymmetry in the oceanic domain of northeastern GOM, (2) the presence of two distinct crustal zones with dramatically different thickness and physical properties, and (3) the observed seismicity within the oceanic domain that is not aligned with any known tectonic structure. The initial Late Jurassic spreading …

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At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions☆, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan F. Suter, Prasanna Gowda Jan 2020

At: A Hydro-Economic Modeling Framework For Aquifer Management In Irrigated Agricultural Regions☆, Mani Rouhi Rad, Erin M.K. Haacker, Vaishali Sharda, Soheil Nozari, Zaichen Xiang, A. Araya, Venkatesh Uddameri, Jordan F. Suter, Prasanna Gowda

Department of Earth and Atmospheric Sciences: Faculty Publications

In this paper, we introduce a hydro-economic modeling framework for the management of groundwater resources that are used for irrigated agricultural production. The model, MOD$$AT, can be used to study the costs of aquifer depletion and the net benefits of specific aquifer management policies. MOD$$AT is composed of three components, namely, an economic component, a hydrologic component and an agronomic component. A main goal of this paper is to introduce the hydro-economic model and describe how it can be transferable to different contexts. With this objective in mind, we describe model components step-by-step so that the process of integration can …

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Mid‐Holocene Grounding Line Retreat And Readvance At Whillans Ice Stream, West Antarctica, R. A. Venturelli, M. R. Siegfried, K. A. Roush, W. Li, J. Burnett, Robert Zook, H. A. Fricker, J. C. Priscu, A. Leventer, B. E. Rosenheim Jan 2020

Mid‐Holocene Grounding Line Retreat And Readvance At Whillans Ice Stream, West Antarctica, R. A. Venturelli, M. R. Siegfried, K. A. Roush, W. Li, J. Burnett, Robert Zook, H. A. Fricker, J. C. Priscu, A. Leventer, B. E. Rosenheim

Department of Earth and Atmospheric Sciences: Faculty Publications

Understanding ice sheet evolution through the geologic past can help constrain ice sheet models that predict future ice dynamics. Existing geological records of grounding line retreat in the Ross Sea, Antarctica, have been confined to ice‐free and terrestrial archives, which reflect dynamics from periods of more extensive ice cover. Therefore, our perspective of grounding line retreat since the Last Glacial Maximum remains incomplete. Sediments beneath Ross Ice Shelf and grounded ice offer complementary insight into the southernmost extent of grounding line retreat, yielding a more complete view of ice dynamics during deglaciation. Here we thermochemically separate the youngest organic carbon …

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Diversity And Equality In Honours And Awards Programs – Steps Towards A Fair Representation Of Membership, Mary Anne Holmes, Latoya Myles, Blair Schneider Jan 2020

Diversity And Equality In Honours And Awards Programs – Steps Towards A Fair Representation Of Membership, Mary Anne Holmes, Latoya Myles, Blair Schneider

Department of Earth and Atmospheric Sciences: Faculty Publications

Honours and awards bestowed by professional societies recognize and reward members who have advanced the goals and values of that society. All too often, however, awards reflect a small network of people who know about the awards and participate in the process. This network works wonderfully for the people lucky enough to be in it, but typically neglects the full range and breadth of scholarship and service within the society. We represent a combined 15C years’ experience on the honours’ committee for a large professional society (the American Geophysical Union) and here offer strategies to increase the representation of honourees.Women …

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