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Articles 4801 - 4830 of 13993

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Development Of The Wrf-Co2 4d-Var Assimilation System V1.0, Tao Zheng, Nancy H. F. French, Martin Baxter May 2018

Development Of The Wrf-Co2 4d-Var Assimilation System V1.0, Tao Zheng, Nancy H. F. French, Martin Baxter

Michigan Tech Publications, Part 1

Regional atmospheric CO2 inversions commonly use Lagrangian particle trajectory model simulations to calculate the required influence function, which quantifies the sensitivity of a receptor to flux sources. In this paper, an adjoint-based four-dimensional variational (4D-Var) assimilation system, WRF-CO2 4D-Var, is developed to provide an alternative approach. This system is developed based on the Weather Research and Forecasting (WRF) modeling system, including the system coupled to chemistry (WRF-Chem), with tangent linear and adjoint codes (WRFPLUS), and with data assimilation (WRFDA), all in version 3.6. In WRF-CO2 4D-Var, CO2 is modeled as a tracer and its feedback to meteorology is ignored. This …


Cyanobacteria Reduce Quagga Mussel (Dreissena Rostriformis Bugensis) Spawning And Fertilization Success, Anna G. Boegehold, Nicholas S. Johnson, Jeffrey L. Ram, Donna R. Kashian May 2018

Cyanobacteria Reduce Quagga Mussel (Dreissena Rostriformis Bugensis) Spawning And Fertilization Success, Anna G. Boegehold, Nicholas S. Johnson, Jeffrey L. Ram, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Quagga mussels (Dreissena rostriformis bugensis) are highly fecund broadcast spawners invasive to freshwaters of North America and western Europe. We hypothesized that environmental cues from phytoplankton can trigger gamete release in quagga mussels. Nutritious algae may stimulate dreissenid spawning, but less palatable food, such as bloom-forming cyanobacteria, could be a hindrance. The objective of our study was to test whether exposure to cyanobacteria can inhibit quagga mussel spawning and fertilization. We assessed spawning in the presence of serotonin, a known spawning inducer, where adult quagga mussels placed in individual vials were exposed to 13 cyanobacteria cultures and purified algal toxin …


Patterns In Caribbean Coral Spawning, Anna C. Jordan May 2018

Patterns In Caribbean Coral Spawning, Anna C. Jordan

HCNSO Student Theses and Dissertations

Most corals worldwide are broadcast spawners that rely on synchronous gamete release for successful fertilization. Spawning synchrony may also decrease the probability of heterospecific fertilization that may produce maladaptive hybrids. Despite the importance of reproductive timing, researchers have only recently begun to collect spawning data across coral species in the Caribbean, but these data remain to be analyzed. This study investigates interannual, seasonal, and environmental patterns that may influence Caribbean scleractinian spawning times. The number of spawning observations varies widely among location and species. Most spawning observations were collected in Florida, Curaçao, and Flower Garden Banks National Marine Sanctuary. Acropora …


Population Dynamics Of The Threatened Staghorn Coral, Acropora Cervicornis, And The Development Of A Species-Specific Monitoring Protocol, Elizabeth Goergen May 2018

Population Dynamics Of The Threatened Staghorn Coral, Acropora Cervicornis, And The Development Of A Species-Specific Monitoring Protocol, Elizabeth Goergen

HCNSO Student Theses and Dissertations

Historically, Acropora cervicornis was found in high densities on many Caribbean, Florida, and Gulf of Mexico reefs. A disease outbreak in the late 1970s and 80s caused up to 99% loss of A. cervicornis cover at some sites, leaving populations sparsely distributed throughout its range and typically found as isolated colonies. Even though populations are depauperate causing a decrease in sexual reproduction, its fast growth rate and ability to reproduce through asexual fragmentation affords this species the potential for quick recovery and population growth. However, limited to no natural recovery has been documented. Many of these populations are poorly studied …


Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick May 2018

Genetic Population And Evolutionary Dynamics Of The Angel Sharks, Squatina Spp., Cristin Keelin Fitzpatrick

HCNSO Student Theses and Dissertations

Once so abundant as to be called the ‘common’ angelshark, Squatina squatina has been extirpated from nearly the entirety of its historical range, from the eastern North Atlantic, to the Mediterranean Sea [International Union for the Conservation of Nature (IUCN) Red List: Critically Endangered]. The angelshark now only occurs in any abundance in the waters surrounding the Canary Islands. I present the first genetic assessment of the angelshark’s population dynamics and diversity from three locations within the Canary Islands archipelago: Gran Canaria, Tenerife, and Lanzarote. Using a suite of individual mitochondrial genome regions [Control region (CR), NADH dehydrogenase subunit 2 …


Biological And Abiotic Factors Influencing Cetacean Mass Strandings In The Northeastern United States, Octavia Williams May 2018

Biological And Abiotic Factors Influencing Cetacean Mass Strandings In The Northeastern United States, Octavia Williams

HCNSO Student Capstones

Marine mammal strandings are frequent occurrences along many coastal areas around the world. The significance of stranded cetaceans has been of interest since around 300 B.C. when philosophers, like Aristotle, pondered why marine mammals, including whales, dolphins and porpoise beach themselves; and famous authors, like Henry David Thoreau, whose fascination in mammal strandings lead him to write a book about these mass occurrences off the coast of Cape Cod. Numerous hypothetical theories have been developed to explain these mass stranding phenomena. Though the causes of mass strandings remain unresolved, recent investigations suggest contributing factors could include environmental elements. Less emphasis …


Water Quality And Freshwater Mussel Assemblages In The Strawberry River Watershed, Arkansas, Irene Sanchez Gonzalez May 2018

Water Quality And Freshwater Mussel Assemblages In The Strawberry River Watershed, Arkansas, Irene Sanchez Gonzalez

Student Theses and Dissertations

Contamination of freshwater resources is an environmental issue worldwide. Habitat alteration and degradation cause water quality decreases and loss of aquatic biodiversity. The Strawberry River in Northeast Arkansas is an example of a highly diverse watershed presenting water quality impairments due to siltation caused by land use alteration. This thesis provides a better understanding of water quality in the tributaries contributing to the Strawberry River and of the freshwater mussel biodiversity of the river. Overall, the Strawberry River tributaries do not exceed criteria assessment but show increased sediment and nutrient concentrations in more agriculturally intense areas. The diversity of freshwater …


Trophic Ecology And Parasitism Of A Mesopelagic Fish Assemblage, Matthew Woodstock May 2018

Trophic Ecology And Parasitism Of A Mesopelagic Fish Assemblage, Matthew Woodstock

HCNSO Student Theses and Dissertations

Mesopelagic (open ocean, 200-1000 m depth) fishes are important consumers of zooplankton and are prey of oceanic predators. Some mesopelagic fishes (e.g., myctophids and stomiids) undertake a diel vertical migration where they ascend to the near-surface waters during the night to feed and descend into the depths during the day to avoid predators. Other mesopelagic fishes (e.g., Sternoptyx spp.) do not vertically migrate and remain at deep depths throughout the day. While in the epipelagic zone (surface – 200 m depth), vertically migrating fishes become prey to upper-trophic level predators, such as: tunas and billfishes. Benthic fishes (e.g., macrourids) often …


Identification And Spatiotemporal Dynamics Of Tuna (Family: Scombridae; Tribe: Thunnini) Early Life Stages In The Oceanic Gulf Of Mexico, Nina Pruzinsky May 2018

Identification And Spatiotemporal Dynamics Of Tuna (Family: Scombridae; Tribe: Thunnini) Early Life Stages In The Oceanic Gulf Of Mexico, Nina Pruzinsky

HCNSO Student Theses and Dissertations

Fishes within the family Scombridae (i.e. tunas, mackerels and bonitos) are of high ecological and economic value, as they are heavily targeted by commercial and recreational fisheries. In coastal and open-ocean environments, adults are high-level predators, while larvae and juveniles serve as prey for numerous species. Much is known about the distribution and abundance of adult tunas, but high taxonomic uncertainty and limited knowledge regarding the distributional patterns of larval and juvenile tunas have led to an “operational taxonomic unit” gap in our understanding of tuna ecology. Scombrids were collected across the Gulf of Mexico (GoM, hereafter) during seven research …


Adam J. Liska: Curriculum Vitae, Adam Liska May 2018

Adam J. Liska: Curriculum Vitae, Adam Liska

Adam Liska Papers

Associate Professor, George Dempster Smith Chair of Industrial Ecology, Departments of Biological Systems Engineering and Agronomy & Horticulture, University of Nebraska-Lincoln 236 L.W. Chase Hall, Lincoln, NE 68583-0726, Ph: (402) 472-8744, e-mail: [email protected]

Ph.D. 2003 Biology (magna cum laude), Max Planck Institute of Molecular Cell Biology & Genetics, Technische Universität Dresden, Dresden, Germany


Light Availability And Phytoplankton Growth Beneath Arctic Sea Ice: Integrating Observations And Modeling, Victoria J. Hill, Bonnie Light, Michael Steele, Richard C. Zimmerman May 2018

Light Availability And Phytoplankton Growth Beneath Arctic Sea Ice: Integrating Observations And Modeling, Victoria J. Hill, Bonnie Light, Michael Steele, Richard C. Zimmerman

OES Faculty Publications

Observations of the seasonal light field in the upper Arctic Ocean are critical to understanding the impacts of changing Arctic ice conditions on phytoplankton growth in the water column. Here we discuss data from a new sensor system, deployed in seasonal ice cover north‐east of Utqiaġvik, Alaska in March 2014. The system was designed to provide observations of light and phytoplankton biomass in the water column during the formation of surface melt ponds and the transition from ice to open water. Hourly observations of downwelling irradiance beneath the ice (at 2.9, 6.9, and 17.9 m depths) and phytoplankton biomass (at …


Irrigation Practice Adoption: Causes And Consequences In The Arkansas Delta, Kerr James Adams May 2018

Irrigation Practice Adoption: Causes And Consequences In The Arkansas Delta, Kerr James Adams

Graduate Theses and Dissertations

Concerns about groundwater depletion from conventional irrigation agriculture in the Arkansas Delta region have led to the promotion of more efficient irrigation practices. With Arkansas being the largest producer of rice, the 10th largest producer of soybeans and the 16th largest producer of corn in the United States, the irrigation demand of these crops has put pressure on producers to find ways to irrigate more efficiently. Not only are the alternative technologies supposed to reduce water use, it is also believed that their adoption can also yield economic benefits for the producer. Despite these assumed benefits, adoption of alternative technologies …


Assessing Effective Rhetoric On Twitter In Relation To Forecast Uncertainty In Hurricane Tracks, Erin K. Lynch May 2018

Assessing Effective Rhetoric On Twitter In Relation To Forecast Uncertainty In Hurricane Tracks, Erin K. Lynch

Atmospheric & Environmental Sciences

A forecast is only as good as the way it is communicated. As the National Weather Service (NWS) transitions to an Impact-Based Communication style, the new public forecasts discuss how to effectively prepare and protect oneself from harm in the face of severe and significant weather. After severe events, meteorologists need to take the time to analyze the language and style of the rhetoric to assess how effective it was at getting people in harm’s way to take protective actions. It is even more important to understand how information was communicated when there is large uncertainty in the forecast. Uncertainty …


Differences Between High Shear / Low Cape Environments In The Northeast Us Favoring Straight-Line Damaging Winds Versus Tornadoes, Michael E. Main, Ross A. Lazear, Lance F. Bosart May 2018

Differences Between High Shear / Low Cape Environments In The Northeast Us Favoring Straight-Line Damaging Winds Versus Tornadoes, Michael E. Main, Ross A. Lazear, Lance F. Bosart

Atmospheric & Environmental Sciences

High shear / low CAPE (HSLC) environments are common in the Northeast US and can occur at any time of year. Severe weather in HSLC environments is notoriously hard to predict, often catching both forecasters and the general public off-guard. The goal of this project is to help forecasters to identify HSLC environments favorable for severe weather in the Northeast US, and to discriminate between HSLC environments that are supportive of tornadoes versus those that favor straight-line damaging winds (SDW). A 10-year HSLC severe weather environmental climatology was created for the Northeast US (New England, New York, New Jersey, Pennsylvania). …


Understanding Microphysical Processes Occurring In Lake-Effect Snowbands Using Quasi-Vertical Profiles Of Wsr-88d Parameters, Marquette Rocque May 2018

Understanding Microphysical Processes Occurring In Lake-Effect Snowbands Using Quasi-Vertical Profiles Of Wsr-88d Parameters, Marquette Rocque

Atmospheric & Environmental Sciences

Knowing the composition and microphysical processes that occur in lake-effect precipitation systems is important in making sure models capture these processes accurately, and could aid forecasters in predicting snow totals and snow water equivalents. Many studies have shown that processes such as riming and dendritic growth can be seen in dual-polarization radar data through parameters such as equivalent radar reflectivity factor, differential reflectivity (ZDR), correlation coefficient, and differential phase. This research examines WSR-88D data from the KTYX (Montague, NY) radar located on the Tug Hill Plateau for several long-lake-axis-parallel lake-effect systems from the Ontario Winter Lake-effect Systems (OWLeS) field campaign …


Numerical Study Of The Interplay Between Thermo-Topographic Slope Flow And Synoptic Flow On Canopy Transport Processes, Xiyan Xu, Chuixiang Yi, Leonardo Montagnani, Eric Kutter May 2018

Numerical Study Of The Interplay Between Thermo-Topographic Slope Flow And Synoptic Flow On Canopy Transport Processes, Xiyan Xu, Chuixiang Yi, Leonardo Montagnani, Eric Kutter

Publications and Research

Canopy flow resulting from interaction between thermo-topographic slope flow and large-scale synoptic flow is very complicated and has been poorly understood. We apply a Reynolds-averaged Navier-Stokes (RANS) turbulence model to investigate how the interactions between local flow and synoptic winds affect CO2 movement in the canopy layer at the Renon site in the Italian Alps. Since the RANS simulations are compared to the data measured by multiple-tower experiments conducted during CarboEurope-IP advection campaigns (ADVEX) at Renon, our study can be viewed as a case study of a relatively common wooded slope. The thermal condition in the canopy is directly …


Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood May 2018

Chemical And Statistical Analysis Of Karst Groundwater Basin Signatures - Springfield, Mo, Benjamin E. Lockwood

Graduate Theses/Dissertations

Springfield, MO is located on the Springfield Plateau physiographic province. The Springfield plateau contains a number of Mississippian aged units and is mainly capped by the Burlington-Keokuk Formation. The Burlington-Keokuk is a highly fossiliferous limestone with nodular and interbedded chert. Beneath the Burlington-Keokuk lies the Elsey, Reeds Spring, and Pierson Formations respectively which comprise the Springfield Plateau aquifer hydrostratigraphic unit. Within the Springfield Plateau aquifer, a well-developed karst system includes springs, sinkholes, and caves. The Springfield Plateau aquifer is the predominant source for springs and seeps in the Springfield area. The purpose of this study was to understand the differences …


Statistical Analysis And Comparison Of Optical Classification Of Atmospheric Aerosol Lidar Data, Kwasi Gyening Afrifa May 2018

Statistical Analysis And Comparison Of Optical Classification Of Atmospheric Aerosol Lidar Data, Kwasi Gyening Afrifa

Electrical & Computer Engineering Projects for D. Eng. Degree

This dissertation presents a new study for the analysis and classification of atmospheric aerosols in remote sensing LIDAR data. Information on particle size and associated properties are extracted from these remote sensing atmospheric data which are collected by a ground-based LIDAR system. This study first considers optical LIDAR parameter-based classification methods for clustering and classification of different types of harmful aerosol particles in the atmosphere. Since accurate methods for aerosol prediction behaviors are based upon observed data, computational approaches must overcome design limitations, and also consider appropriate calibration and estimation accuracy. Consequently, two statistical methods based on generalized linear models …


Road Weather Impact Based Decision Support Applications: Developing A Department Of Transportation Winter Severity Index, Curtis Louis Walker May 2018

Road Weather Impact Based Decision Support Applications: Developing A Department Of Transportation Winter Severity Index, Curtis Louis Walker

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

Adverse weather conditions are responsible for millions of vehicular crashes, thousands of vehicular deaths and billions of dollars in economic and congestion costs. Many transportation agencies utilize a performance or mobility metric to assess how well they are maintaining road access. This research focuses on the development of a winter severity index for the State of Nebraska (NEWINS). NEWINS is an event-driven index that was derived for the Nebraska Department of Transportation (NDOT) and its districts across the state. The NEWINS framework includes a categorical storm classification framework and climatological aspect to capture atmospheric conditions more accurately across diverse spatial …


Neogene Stratigraphy And Paleoenvironments In The Lauca Basin Of Northern Chile, Amanda Jones May 2018

Neogene Stratigraphy And Paleoenvironments In The Lauca Basin Of Northern Chile, Amanda Jones

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

This thesis examines a late Miocene to Pliocene sedimentary succession in the Lauca Basin, a topographically isolated, fluvio-lacustrine basin in the northern Chilean Altiplano. A sedimentary section within the Lauca Basin, composed of Lauca Formation sediments, was investigated using stratigraphic and petrographic analyses to define the Miocene to Pliocene paleoenvironmental history of the region. Geochronologic results indicate the section ranges in age from approximately 5.57 +/- 0.20 Ma to 5.44 +/- 0.16 Ma. The sedimentology of 36 samples was described, and twelve samples were analyzed petrographically. Five lithofacies were characterized: laminated mudstone (Fl), volcaniclastic mudstone (Fv), carbonate (C), evaporite (E), …


Regional Stratigraphy And Distribution Of The Coastal Group, St. Elizabeth Parish, Southwestern Jamaica, Brett M. Kenning May 2018

Regional Stratigraphy And Distribution Of The Coastal Group, St. Elizabeth Parish, Southwestern Jamaica, Brett M. Kenning

Graduate Theses/Dissertations

This contribution examines the characteristics and ages of sedimentary units in the Coastal Group located along the southwestern Jamaica coast between Great Pedro Bluff and Fort Charles Bay in southwestern St. Elizabeth Parish. The coastline is characterized by laterally discontinuous low cliff exposures, separated by modern beach deposits and tectonically raised shore platforms composed of the White Limestone Group (mid-Eocene to mid-Miocene) and coral rudstone to floatstone and calcareous sandstone of the Coastal Group (late Pleistocene). Electron-Spin Resonance spectroscopy conducted on corals collected from a coral rudstone to floatstone facies yielded an estimated age of 120 ka. The coral facies …


A Geospatial Study Of The Drought Impact On Surface Water Reservoirs: Study Cases From Texas And California, Zachary Asbury May 2018

A Geospatial Study Of The Drought Impact On Surface Water Reservoirs: Study Cases From Texas And California, Zachary Asbury

Graduate Theses and Dissertations

Drought in Texas and California has been a long-term problem. Over the past 60 years reservoir construction has occurred to remedy the situation. Satellite imagery has been used historically to measure and monitor fluctuations in surface water reservoirs. This investigation integrates remote sensing and geographic information system (GIS) technologies to study the impact of drought on selected surface water reservoirs in San Angelo and Dallas in Texas, and Lake Oroville in California. Expansion and shrinkage over the 2005-2016 period reveal the concrete impact that drought, along with other factors, have on the selected lakes. Fluctuations in reservoir sizes during summer …


How College Campuses Are Using Social Media During Severe Weather Events, Emmale Davis May 2018

How College Campuses Are Using Social Media During Severe Weather Events, Emmale Davis

Graduate Theses and Dissertations

This study explores how college campuses are using social media during severe weather events. This topic surfaced after a tornado devastated Moore, Oklahoma in May 2013 and those displaced flocked to the University of Oklahoma campus after a post made on Twitter went viral prior to an official message being sent out by the university. In order to further explore this topic, a qualitative phenomenological case study was conducted at the following sites: University of Alabama, Missouri Southern State University, University of Oklahoma, and Florida State University. This study included observations of social media posts on Facebook and Twitter on …


Morphologic Evolution Of A Nearshore Berm: One Year Monitoring At Ft. Myers Beach, Florida, Kristopher Jason Enfinger May 2018

Morphologic Evolution Of A Nearshore Berm: One Year Monitoring At Ft. Myers Beach, Florida, Kristopher Jason Enfinger

Theses and Dissertations

Nourishment in the form of a nearhsore berm has become an important alternative method to protecting shorelines and introducing sediment back into the littoral system. In 2009, a nearshore berm was constructed at Ft. Myers Beach, Florida by the U.S. Army Corps of Engineers through maintenance dredging of a nearby navigational channel at Matanzas Pass. Constructed in the form of a nearshore bar, the berm was one of the shallowest placements in a low-wave energy setting. The Coastal Research Lab at the University of South Florida (USF-CRL) conducted field monitoring for the first four years after the construction. This project …


2018 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University May 2018

2018 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

No abstract provided.


Gis Modeling Of The Prominent Geohazards In Arkansas, Kyle Walker Rowden May 2018

Gis Modeling Of The Prominent Geohazards In Arkansas, Kyle Walker Rowden

Graduate Theses and Dissertations

The State of Arkansas is prone to numerous geohazards. This thesis is a twofold study of prominent geohazards in Arkansas: the first fold includes a novel triggerless approach for mass wasting susceptibility modeling applied to the Boston Mountains in NW Arkansas, and the second fold is a GIS-based regression modeling of the extreme weather patterns at the state level. Each study fold is presented in this thesis as a separate chapter embracing a published peer-reviewed paper. In the first paper, I have used the analytical hierarchy process to assign preliminary statistical weights to the most cogent variables influencing mass wasting …


Applications Of Reservoir Limnology Theory And Steady-State Modeling To Eutrophication Management In Beaver Lake, Arkansas, Matthew Rich May 2018

Applications Of Reservoir Limnology Theory And Steady-State Modeling To Eutrophication Management In Beaver Lake, Arkansas, Matthew Rich

Graduate Theses and Dissertations

Reservoir limnology theory predicts that phytoplankton biomass (PB) is greatest in riverine-transition zones and least in lacustrine zones leading to an inverse pattern in water clarity. These theoretical patterns were utilized to create a statistical model of chlorophyll-a (Chl-a), an indicator of PB, and Secchi transparency (ST), an indicator of Chl-a, in Beaver Lake, Arkansas, a 12,800-ha reservoir, in order to hindcast historical conditions. Sampling for Chl-a, ST, and photic depth occurred semimonthly at 12 locations along a 78-km transect from the river inflow to the dam during the 2015 growing season. The ratio of Chl-a and ST measured at …


Greenhouse Gas Emissions And Management Practices That Affect Emissions In Us Rice Systems, Bruce A. Linquist, Mathias Marcos, M. Arlene Adviento-Borbe, Merle Anders, Dustin Harrell, Steve Linscombe, Michele L. Reba, Benjamin R.K. Runkle, Lee Tarpley, Allison Thomson May 2018

Greenhouse Gas Emissions And Management Practices That Affect Emissions In Us Rice Systems, Bruce A. Linquist, Mathias Marcos, M. Arlene Adviento-Borbe, Merle Anders, Dustin Harrell, Steve Linscombe, Michele L. Reba, Benjamin R.K. Runkle, Lee Tarpley, Allison Thomson

Biological and Agricultural Engineering Faculty Publications and Presentations

Previous reviews have quantified factors affecting greenhouse gas (GHG) emissions from Asian rice (Oryza sativa L.) systems, but not from rice systems typical for the United States, which often vary considerably particularly in practices (i.e., water and carbon management) that affect emissions. Using meta‐analytic and regression approaches, existing data from the United States were examined to quantify GHG emissions and major practices affecting emissions. Due to different production practices, major rice production regions were defined as the mid‐South (Arkansas, Texas, Louisiana, Mississippi, and Missouri) and California, with emissions being evaluated separately. Average growing season CH4 emissions for the mid‐South and …


Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel May 2018

Thermal Removal Of Carbon Dioxide From The Atmosphere: Energy Requirements And Scaling Issues, Ted Von Hippel

Publications

I conduct a systems-level study of direct air capture of CO2 using techniques from thermal physics. This system relies on a combination of an efficient heat exchanger, radiative cooling, and refrigeration, all at industrial scale and operated in environments at low ambient temperatures. While technological developments will be required for such a system to operate efficiently, those developments rest on a long history of refrigeration expertise and technology, and they can be developed and tested at modest scale. I estimate that the energy required to remove CO2 via this approach is comparable to direct air capture by other techniques. The …


The Relationship Between Measures Of Annual Livestock Disturbance In Western Riparian Areas And Stream Conditions Important To Trout, Salmon, And Char, Lindsey M. Goss, Brett B. Roper Apr 2018

The Relationship Between Measures Of Annual Livestock Disturbance In Western Riparian Areas And Stream Conditions Important To Trout, Salmon, And Char, Lindsey M. Goss, Brett B. Roper

Watershed Sciences Faculty Publications

Managing livestock disturbance in riparian zones in a manner that provides economic returns to ranchers while protecting streams is an important aspect of rangeland management on public lands in the western United States. Attempts to balance economic and ecologic outcomes have been made more difficult due to the presence of several salmonid species that are protected under the Endangered Species Act. One approach to proper management of livestock use near streams has been to define the allowable limits of disturbance using 2 metrics, streambank alteration and stubble height. We evaluated 153 stream reaches within the Interior Columbia Basin to determine …