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2014

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Articles 421 - 450 of 512

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Climate Risk Analysis On The Food Security In Saguday, Quirino Province, Jose Santos R. Carandang, Glenn S. Banaguas Jan 2014

Climate Risk Analysis On The Food Security In Saguday, Quirino Province, Jose Santos R. Carandang, Glenn S. Banaguas

Angelo King Institute for Economic and Business Studies (AKI)

Saguday is a 5th-class municipality of Quirino Province. The nine barangays of Saguday namely – La Paz, Cardenas, Salvacion, Santo Tomas, Rizal, Tres Reyes, Dibul, Cardenas and Gamis – are all vulnerable to climate change and calamities, not only because of the scarce resources of the municipality, but also due to the geographical and climatological condition of the area. Rainfall rates are projected to increase due to climate change and there will also be some likely increase in mean maximum tropical cyclone wind speed due to the projected 21st century warming (Knutson et al., 2010). Its location in Quirino Province …


Numerical Investigation Of Orographic Effects On Supercell Thunderstorms, Galen M. Smith Jan 2014

Numerical Investigation Of Orographic Effects On Supercell Thunderstorms, Galen M. Smith

Dissertations

Orographic effects on tornadic supercell development, propagation, and structure are investigated using the Cloud Model 1 with idealized bell-shaped mountains of various heights and geometries and a homogeneous fluid flow with a single sounding. In total, the variations of height and geometry yield 16 terrain configurations. It is found that blocking effects are dominative compared to the terrain-induced environmental heterogeneity downwind of the mountain. The isolated bell-shaped mountains tended to shift the track of the storm towards the left of storm motion; however, when the terrain was elongated the effect tended to be rightward. The terrain blocking effect also enhanced …


The Role Of Politics And Proximity In Sea Level Rise Policy Salience: A Study Of Virginia Legislators’ Perceptions, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Ivan K. Ash Jan 2014

The Role Of Politics And Proximity In Sea Level Rise Policy Salience: A Study Of Virginia Legislators’ Perceptions, Juita-Elena (Wie) Yusuf, Burton St. John Iii, Ivan K. Ash

School of Public Service Faculty Publications

The acceleration of sea level rise (SLR) has become a threat to the stability of nation-states worldwide and associated with risks to environmental sustainability, economic infrastructure, and public health. However, from both an international and U.S. perspective, there is a lack of research examining legislative decision makers’ perceptions about policies regarding SLR. This study addresses that gap by examining how politics and proximity affects Virginia state legislators’ perceptions of the saliency of SLR. A survey of these legislators reveals their perceptions of credible sources of information, SLR-related risk, and who should take the lead to address SLR. While this study …


The Potential Release Of Phosphorus In Floodplains, Maria S. Rossetti, Nicole K. Ownby, Erin Scott, Brian E. Haggard Jan 2014

The Potential Release Of Phosphorus In Floodplains, Maria S. Rossetti, Nicole K. Ownby, Erin Scott, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

In the Illinois River Watershed, there has been growing concern over elevated phosphorus concentrations in the water column. This study evaluated how much phosphorus is contributed from floodplain soils into surface waters, examining the relationship between the flux of phosphorus released and the amount of phosphorus stored in the soil. This was investigated by artificially inundating soil cores from four sites and determining the soluble reactive phosphorus concentrations of the overlying water and the levels of Water and Mehlich-3 extractable phosphorus in the soil. The flux of phosphorus to the overlying water ranged from 0.43 to 6.61 mg m-2 hr-1 …


Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard Jan 2014

Reducing Water Extractable Phosphorus In Poultry Litter Using Chitosan Treatment, Zachary Simpson, Brina Smith, David A. Zaharoff, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Phosphorus (P) is an important factor in the eutrophication of freshwater, and watershed sources include effluent discharges and the landscape. Poultry litter applied to the landscape can be a potential source of P, which is dependent on rainfall, runoff and dissolution. Chitosan, the deacetylated form of the biopolymer chitin, has been shown to have an effect on reducing water extractable phosphorus (WEP) in poultry litter when applied as a powder. The intent of this study was to measure the effect that poultry litter treatment (PLT), acetic acid and incubation time have on chitosan’s ability to reduce WEP in poultry litter. …


Monitoring Ship Noise To Assess The Impact Of Coastal Developments On Marine Mammals, Nathan D. Merchant, Enrico Pirotta, Tim R. Barton, Paul M. Thompson Jan 2014

Monitoring Ship Noise To Assess The Impact Of Coastal Developments On Marine Mammals, Nathan D. Merchant, Enrico Pirotta, Tim R. Barton, Paul M. Thompson

Biology - All Scholarship

The potential impacts of underwater noise on marine mammals are widely recognised, but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. This paper characterises natural and anthropogenic contributors to underwater noise at two sites in the Moray Firth Special Area of Conservation, an important marine mammal habitat that may be exposed to increased shipping activity from proposed offshore energy developments. We aimed to establish a pre-develop- ment baseline, and to develop ship noise monitoring methods using Automatic Identification System (AIS) and time-lapse video to record trends in noise levels and shipping activity. Our results …


Feeding Ecology Of The Sandbar Shark In South Carolina Estuaries Revealed Through Δ13c And Δ15n Stable Isotope Analysis, David S. Shiffman, Bryan S. Frazier, John R. Kucklick, Daniel Abel, Jay Brandes, Gorka Sancho Jan 2014

Feeding Ecology Of The Sandbar Shark In South Carolina Estuaries Revealed Through Δ13c And Δ15n Stable Isotope Analysis, David S. Shiffman, Bryan S. Frazier, John R. Kucklick, Daniel Abel, Jay Brandes, Gorka Sancho

Marine Science

Abstract: Stable isotope ratios of carbon and nitrogen (δ13C and δ15N) from muscle samples were used to examine the feeding ecology of a heavily exploited shark species, the Sandbar Shark Carcharhinus plumbeus. Two hundred and sixty two Sandbar Sharks were sampled in five South Carolina estuaries. There were no significant differences in average δ13C or δ15N signatures between estuaries, between sampling years, or between male and female Sandbar Sharks, suggesting that these variables do not affect diet. A potential ontogenetic diet shift between young-of-year and juvenile Sandbar Sharks in South Carolina, similar …


Numerical Experiments Of Hurricane Impact On Vertical Mixing And De-Stratification Of The Louisiana Shelf Waters, Mohammadnabi Allahdadi Jan 2014

Numerical Experiments Of Hurricane Impact On Vertical Mixing And De-Stratification Of The Louisiana Shelf Waters, Mohammadnabi Allahdadi

LSU Doctoral Dissertations

The numerical model FVCOM (Finite Volume Community Ocean Model) was applied to study the effects of Hurricane Katrina on the vertical mixing over the Louisiana shelf and the process of post-storm re-stratification. Wind field from Hurricane Katrina was generated using a single vortex analytical model and was evaluated using available wind measurements over the shelf. Simulations of shelf circulation under Hurricane Katrina were done through several numerical tests to find the best approach for treating vertical eddy viscosity. Model results for the shelf during Katrina demonstrated opposite currents between surface and bottom for most of the shelf area. Results also …


Estimating Sustainable Harvests Of Eastern Oysters, Crassostrea Virginica, Thomas M. Soniat, Nathan Cooper, Eric N. Powell, John M. Klinck, Mahdi Abdelguerfi, Shengru Tu, Roger Mann, Patrick D. Banks Jan 2014

Estimating Sustainable Harvests Of Eastern Oysters, Crassostrea Virginica, Thomas M. Soniat, Nathan Cooper, Eric N. Powell, John M. Klinck, Mahdi Abdelguerfi, Shengru Tu, Roger Mann, Patrick D. Banks

CCPO Publications

Sustainability of a fishery is traditionally and typically considered achieved if the exploited population does not decline in numbers or biomass over time as a result of fishing relative to biological reference point goals. Oysters, however, exhibit atypical population dynamics compared with many other commercial species. The population dynamics often display extreme natural interannual variation in numbers and biomass, and oysters create their own habitat--the reef itself. With the worldwide decline of oyster reef habitat and the oyster fisheries dependent thereon, the maintenance of shell has received renewed attention as essential to population sustainability. We apply a shell budget model …


A Comparative Study Of Sea Level Reconstruction Techniques Using 20 Years Of Satellite Altimetry Data, M. W. Strassburg, B. D. Hamlington, R. R. Leben, K.-Y. Kim Jan 2014

A Comparative Study Of Sea Level Reconstruction Techniques Using 20 Years Of Satellite Altimetry Data, M. W. Strassburg, B. D. Hamlington, R. R. Leben, K.-Y. Kim

CCPO Publications

Sea level reconstructions extend spatially dense data sets, such as those from satellite altimetry, by decomposing the data set into basis functions and fitting those functions to in situ tide gauge measurements with a longer temporal record. We compare and evaluate two methods for reconstructing sea level through an idealized study. The compared sea level reconstruction methods differ in the technique for calculating basis functions, i.e., empirical orthogonal functions (EOFs) versus cyclostationary EOFs (CSEOFs). Reconstructions are created using Archiving, Validation, and Interpretation of Satellite Oceanographic (AVISO) satellite altimetry data and synthetic tide gauges. Synthetic tide gauge records are simulated using …


Diuron From Maui Sugarcane Field Runoff Is Potentially Harmful To Local Coral Reefs, Thomas C. Royer, Patricia A. Tester, Thomas N. Stewart Jan 2014

Diuron From Maui Sugarcane Field Runoff Is Potentially Harmful To Local Coral Reefs, Thomas C. Royer, Patricia A. Tester, Thomas N. Stewart

CCPO Publications

In a grassroots effort to identify stressors influencing the health of Maui’s coral reefs, samples for the pre- and post-emergent herbicide, Diuron, were taken in July–August 2013, prior to, during, and after the passage of Tropical Storm Flossie on the south central coast of Maui, Hawaii. Diuron is routinely used on sugarcane fields adjacent to Hawaiian coastal waters and is a component of the anti-fouling paint used on small boats. It inhibits photosynthesis of terrestrial plants at concentrations as low as 0.1 parts per billion and can be lethal to endosymbiotic dinoflagellates in corals at concentrations less than 3 parts …


Does Reproductive Potential Of Red Snapper In The Northern Gulf Of Mexico Differ Among Natural And Artificial Habitats?, Hilary Day Glenn Jan 2014

Does Reproductive Potential Of Red Snapper In The Northern Gulf Of Mexico Differ Among Natural And Artificial Habitats?, Hilary Day Glenn

LSU Master's Theses

This study compares the reproductive potential of red snapper (Lutjanus campechanus) at artificial and natural habitats. Natural habitats are areas of vertical relief created from biogenic/geologic processes that are thought to be the historical centers of abundance for red snapper in the northern Gulf of Mexico. Red snapper were collected from 2011 to 2013 at three natural habitat sites and two artificial habitat oil and gas platform sites. The mean gonadosomatic indices (GSI), maturity at size and age, spawning indicators, batch fecundity, spawning frequency, and annual fecundity for red snapper at each habitat were analyzed to examine reproductive potential among …


Legacy Phosphorus Implications In The Lake Pontchartrain Estuary Sediment Due To The 2011 Bonnet Carre Spillway Opening, Nhan Thanh Nguyen Jan 2014

Legacy Phosphorus Implications In The Lake Pontchartrain Estuary Sediment Due To The 2011 Bonnet Carre Spillway Opening, Nhan Thanh Nguyen

LSU Master's Theses

Phosphorus (P) is an essential nutrient for life and excess P in aquatic systems can trigger algal blooms. Nutrient-rich Mississippi River water is diverted into the Lake Pontchartrain estuary (LPE) periodically through the Bonnet Carré Spillway (BCS) to avoid downstream flooding to the city of New Orleans, Louisiana and can significantly increase the internal P load in the sediment. A sequential P fractionation procedure was performed on sediments collected before the opening and after the closing of the 2011 BCS operation to understand the role of these large river diversions on P dynamics. Before the 2011 BCS opening, 10,368 Mt …


Hurricane-Induced Geologic Change And Palynological Assessment Of A Rapidly Subsiding Deltaic Environment In Coastal Louisiana, James Dustin Naquin Jan 2014

Hurricane-Induced Geologic Change And Palynological Assessment Of A Rapidly Subsiding Deltaic Environment In Coastal Louisiana, James Dustin Naquin

LSU Master's Theses

This study is focused on a paleoenvironmental history of a backbarrier coastal lagoon situated on the seaward margin of the Lafourche delta lobe in coastal Louisiana. A 2.2 meter long sediment core (Core BC 53) was collected from a mangrove-covered land strip on the northern margin of Bay Champagne, and was studied using pollen analysis, Loss-on-ignition (LOI), X-ray Fluorescence (XRF) analysis, and Cesium-137 and radiocarbon dating techniques to establish sediment stratigraphy and core chronology. Bay Champagne, a backbarrier lagoon formed during the evolution of Bayou Lafourche, has shown to be highly sensitive to geomorphological and vegetation changes induced by sea-level …


Cdom Optical Properties Near Dwh Site, Gulf Of Mexico: Pot Oil Spill, Zhi Li Jan 2014

Cdom Optical Properties Near Dwh Site, Gulf Of Mexico: Pot Oil Spill, Zhi Li

LSU Master's Theses

The Deep Water Horizon (DWH) oil spill resulted in the largest accidental release of crude oil in U.S. waters with both short- and long-term effects on the marine environment. Extensive studies conducted immediately following the oil spill in the northern Gulf of Mexico provided greater understanding of the physical processes influencing the distribution of the released oil, including the use of optical detection of polycyclic aromatic hydrocarbons (PAHs), a toxic crude oil fraction in the northern Gulf of Mexico. In this study, the optical properties of chromophoric dissolved organic matter (CDOM) and the concentrations of dissolved organic carbon (DOC) were …


Assessment Of Habitat Quality For Red Snapper, Lutjanus Campechanus, In The Northwestern Gulf Of Mexico: Natural Vs. Artificial Reefs, Brittany Dawn Schwartzkopf Jan 2014

Assessment Of Habitat Quality For Red Snapper, Lutjanus Campechanus, In The Northwestern Gulf Of Mexico: Natural Vs. Artificial Reefs, Brittany Dawn Schwartzkopf

LSU Master's Theses

Habitat quality of natural and artificial reefs for red snapper (Lutjanus campechanus) in the northwestern Gulf of Mexico (Gulf) is important as this area is home to the majority of the Gulf’s artificial reef system, in the form of oil and gas platforms, in addition to the largest extent of high vertical relief natural habitat. This study sought to assess habitat quality of natural reefs of varying habitat complexity and an artificial reef complex located on the LA continental shelf. Habitat quality was assessed by comparing red snapper diets and foraging patterns, and nutritional condition using the liver-somatic index (LSI) …


Nutrient And Sediment Effects On Oligohaline Marsh Plant Community In Mississippi River Delta, Sareh Poormahdi Jan 2014

Nutrient And Sediment Effects On Oligohaline Marsh Plant Community In Mississippi River Delta, Sareh Poormahdi

LSU Master's Theses

The Mississippi River Delta comprises approximately 40% of the coastal wetlands in the conterminous United States, but has experienced more than 80% of the wetland loss in part due to flood control levees that have hydrologically isolated the lower River from the adjacent wetlands for a century. Thus, reconnecting the River to the wetlands through diversions is one of the approaches being used to reduce the rate of wetland loss. However, the diversion structures were originally designed to deliver freshwater rather than sediment. Furthermore, nutrient concentrations in the River water have increased during the past half-century as a result of …


Effect Of The Bp Deepwater Horizon Oil Spill On Critical Marsh Soil Microbial Functions, Jason Paul Pietroski Jan 2014

Effect Of The Bp Deepwater Horizon Oil Spill On Critical Marsh Soil Microbial Functions, Jason Paul Pietroski

LSU Master's Theses

On April 20, 2010, the BP Deepwater Horizon (DWH) offshore oil platform exploded releasing ~ 795 million L of southern Louisiana (LA) light sweet crude oil into the Gulf of Mexico. Approximately 7.9 million liters of dispersant, Corexit EC9500A, were applied for remediation. The effect of BP DWH crude oil and Corexit EC9500A on two marsh soil microbial processes, (mineralizable nitrogen and denitrification), were examined in the laboratory. Surface soil samples were collected from an unimpacted salt marsh site proximal to areas that suffered light to heavily oiling in Barataria Bay, LA. Additions of oil were at a ratio of …


Polonium-210 Dynamics In The Northern Gulf Of Mexico, Patrick Robert Jones Jan 2014

Polonium-210 Dynamics In The Northern Gulf Of Mexico, Patrick Robert Jones

LSU Master's Theses

Polonium-210 (t1/2=138 d) is the most common among the 33 known radioisotopes of Polonium found in the natural environment. It is produced by the radioactive decay of its long-lived grandparent Lead-210(t1/2=22.3 d) via Bismuth-210 (t1/2=5.012 d) and forms as part of the natural Uranium-238 decay series. The primary hazard associated with Polonium-210 is its radioactivity, as an alpha particle emitter. Marine organisms receive their maximum radioactive dose in the natural environment from Polonium-210. Polonium has been known to bioaccumulate in the marine food web and can be potentially harmful to humans via the intake of certain marine organisms. Thus it …


Failed Agricultural Impoundments: An Interdisciplinary Assessment Of Community Structure And Social Resilience, Stacy Nicole Peterson Jan 2014

Failed Agricultural Impoundments: An Interdisciplinary Assessment Of Community Structure And Social Resilience, Stacy Nicole Peterson

LSU Master's Theses

The remnants of the wetland reclamation era of the early 1900s are visible in the leveed, drained, and failed impoundments across the United States, and especially in coastal regions. The common themes of their history are flooding, restoration, and – sometimes - community resilience. The physical changes occurring during and after impoundment, and after failure includes subsidence, erosion, and flooding are well-documented. Here I construct an environmental history that integrates data on these physical changes with archival records, historical documents, site visits and personal interviews. The primary region of focus is ‘Delta Farms’ - a failed agricultural impoundment in Lafourche …


Proportionality Of Population Descriptors Of Metacercariae Of Clinostomum Marginatum In The Orobranchial Cavity Of Black Bass (Micropterus Spp.) From Arkansas Ozark And Ouachita Streams, J. J. Daly Sr. Jan 2014

Proportionality Of Population Descriptors Of Metacercariae Of Clinostomum Marginatum In The Orobranchial Cavity Of Black Bass (Micropterus Spp.) From Arkansas Ozark And Ouachita Streams, J. J. Daly Sr.

Journal of the Arkansas Academy of Science

In a previous study of Clinostomum marginatum metacercariae in Micropterus dolomieu, I reported that the population parameters of mean abundance, standard deviation, maximum abundance, mean intensity and mean intensity standard deviation were proportional between the total population and the orobranchial numbers for 16 locations in Arkansas Ozark and Ouachita streams. This allowed an assessment of the parasite populations by only examining the mouth and gill areas without sacrificing a valued sports fish. The present study examined the same orobranchial parameters utilizing correlation and descriptive statistics to determine if proportionality also existed between the different localities. I have now included an …


State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2014, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Kimberly Mann, Radha Pyati, Gretchen Bielmyer-Fraser, Stuart Chalk, Peter Bacopoulos, Brian P. Zoellner Jan 2014

State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2014, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University, Lucy Sonnenberg, Gerry Pinto, Nisse Goldberg, Kimberly Mann, Radha Pyati, Gretchen Bielmyer-Fraser, Stuart Chalk, Peter Bacopoulos, Brian P. Zoellner

State of the River Report

No abstract provided.


From Alarm To Action: Closing The Gap Between Belief And Behavior In Response To Climate Change, Kathryn Laing Doherty Jan 2014

From Alarm To Action: Closing The Gap Between Belief And Behavior In Response To Climate Change, Kathryn Laing Doherty

Antioch University Dissertations & Theses

The degree to which the climate continues to change will largely be determined by choices made by individuals and nations regarding greenhouse gas emissions. Many Americans engage in energy conservation actions. But, the political will in the United States to adopt emissions reduction policies is unlikely to exist without public demand. Therefore, public mitigation actions of individuals (e.g., contacting elected officials in support of emissions reduction) are critical to induce legislative response. The majority of individuals who are most concerned about climate change (the “Alarmed” segment) do not engage in public mitigation actions, but some do. The purpose of this …


Editorial-The 5th International Workshop On Modeling The Ocean (Iwmo 2013), Jarle Berntsen, Lie-Yauw Oey, Tal Ezer, Richard Greatbatch, Huijie Xue, Yasumasa Miyazawa Jan 2014

Editorial-The 5th International Workshop On Modeling The Ocean (Iwmo 2013), Jarle Berntsen, Lie-Yauw Oey, Tal Ezer, Richard Greatbatch, Huijie Xue, Yasumasa Miyazawa

CCPO Publications

The 5th International Workshop on Modeling the Ocean (IWMO http://www.uib.no/en/IWMO2013/-58927/iwmo2013-bergen-norway) was held in June 17–20, in Bergen, Norway. The historic city of Bergen is the gateway to the fjords and a center for oceanic research. The workshop was hosted by the University of Bergen and also sponsored by the Research Council of Norway. Approximately 80 researchers worldwide participated in the workshop. Professor Mellor, Princeton University, gave the keynote lecture.


Estimating The Benthic Efflux Of Dissolved Iron On The Ross Sea Continental Shelf, C. M. Marsay, P. N. Sedwick, M. S. Dinniman, P. M. Barrett, S. L. Mack, D. J. Mcgillicuddy Jr. Jan 2014

Estimating The Benthic Efflux Of Dissolved Iron On The Ross Sea Continental Shelf, C. M. Marsay, P. N. Sedwick, M. S. Dinniman, P. M. Barrett, S. L. Mack, D. J. Mcgillicuddy Jr.

CCPO Publications

Continental margin sediments provide a potentially large but poorly constrained source of dissolved iron (dFe) to the upper ocean. The Ross Sea continental shelf is one region where this benthic supply is thought to play a key role in regulating the magnitude of seasonal primary production. Here we present data collected during austral summer 2012 that reveal contrasting low surface (0.08 +/- 0.07 nM) and elevated near-seafloor (0.74 +/- 0.47 nM) dFe concentrations. Combining these observations with results from a high-resolution physical circulation model, we estimate dFe efflux of 5.8 x 10(7) mol yr(-1) from the deeper portions (>400m) …


Accelerated Flooding Along The U.S. East Coast: On The Impact Of Sea-Level Rise, Tides, Storms, The Gulf Stream, And The North Atlantic Oscillations, Tal Ezer, Larry P. Atkinson Jan 2014

Accelerated Flooding Along The U.S. East Coast: On The Impact Of Sea-Level Rise, Tides, Storms, The Gulf Stream, And The North Atlantic Oscillations, Tal Ezer, Larry P. Atkinson

CCPO Publications

Recent studies identified the U.S. East Coast north of Cape Hatteras as a 'hotspot' for accelerated sea-level rise ( SLR), and the analysis presented here shows that the area is also a 'hotspot for accelerated flooding.' The duration of minor tidal flooding [defined as 0.3 m above MHHW (mean higher high water)] has accelerated in recent years for most coastal locations from the Gulf of Maine to Florida. The average increase in annual minor flooding duration was ∼20 h from the period before 1970 to 1971-1990, and ∼50 h from 1971-1990 to 1991-2013; spatial variations in acceleration of flooding resemble …


Morphology And Mixing State Of Atmospheric Particles: Links To Optical Properties And Cloud Processing, Swarup China Jan 2014

Morphology And Mixing State Of Atmospheric Particles: Links To Optical Properties And Cloud Processing, Swarup China

Dissertations, Master's Theses and Master's Reports - Open

Atmospheric particles are ubiquitous in Earth’s atmosphere and impact the environment and the climate while affecting human health and Earth’s radiation balance, and degrading visibility. Atmospheric particles directly affect our planet’s radiation budget by scattering and absorbing solar radiation, and indirectly by interacting with clouds. Single particle morphology (shape, size and internal structure) and mixing state (coating by organic and inorganic material) can significantly influence the particle optical properties as well as various microphysical processes, involving cloud-particle interactions and including heterogeneous ice nucleation and water uptake. Conversely, aerosol cloud processing can affect the morphology and mixing of the particles. For …


Investigating The Role Of The Contact Line In Heterogeneous Nucleation With High Speed Imaging, Colin Gurganus Jan 2014

Investigating The Role Of The Contact Line In Heterogeneous Nucleation With High Speed Imaging, Colin Gurganus

Dissertations, Master's Theses and Master's Reports - Open

While nucleation of solids in supercooled liquids is ubiquitous [15, 65, 66], surface crystallization, the tendency for freezing to begin preferentially at the liquid-gas interface, has remained puzzling [74, 18, 68, 69, 51, 64, 72, 16]. Here we employ high-speed imaging of supercooled water drops to study the phenomenon of heterogeneous surface crystallization. Our geometry avoids the "point-like contact" of prior experiments by providing a simple, symmetric contact line (triple line defined by the substrate-liquid-air interface) for a drop resting on a homogeneous silicon substrate. We examine three possible mechanisms that might explain these laboratory observations: (i) Line Tension at …


Compositions And Constituents Of Freshwater Dissolved Organic Matter Isolated By Reverse Osmosis, Yulong Zhang, Wen Huang, Jingdong Mao Jan 2014

Compositions And Constituents Of Freshwater Dissolved Organic Matter Isolated By Reverse Osmosis, Yulong Zhang, Wen Huang, Jingdong Mao

Chemistry & Biochemistry Faculty Publications

Dissolved organic matter (DOM) from riverine and lacustrine water was isolated using a reverse osmosis (RO) system. Solid-state 13C nuclear magnetic resonance (13C NMR) was used to quantitatively evaluate the compositions and constituents of DOM, which are compared with previous investigations on marine DOM. Results indicated that concentration factor (CF) was a key metric controlling yield and sorption of DOM on the RO system. The sorption was likely non-selective, based on the 13C NMR and δ13C analyses. Carbohydrates and lipids accounted for 25.0–41.5% and 30.2–46.3% of the identifiable DOM, followed by proteins (18.2–19.8%) and …


Validation Of Mipas Imk/Iaa V5r_O3_224 Ozone Profiles, A. Laeng, U. Grabowski, T. Von Clarmann, G. Stiller, N. Glatthor, M. Höpfner, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, P. F. Bernath Jan 2014

Validation Of Mipas Imk/Iaa V5r_O3_224 Ozone Profiles, A. Laeng, U. Grabowski, T. Von Clarmann, G. Stiller, N. Glatthor, M. Höpfner, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

We present the results of an extensive validation program of the most recent version of ozone vertical profiles retrieved with the IMK/IAA (Institute for Meteorology and Climate Research/Instituto de Astrofisica de Andalucia) MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) research level 2 processor from version 5 spectral level 1 data. The time period covered corresponds to the reduced spectral resolution period of the MIPAS instrument, i.e., January 2005-April 2012. The comparison with satellite instruments includes all post-2005 satellite limb and occultation sensors that have measured the vertical profiles of tropospheric and stratospheric ozone: ACE-FTS, GOMOS, HALOE, HIRDLS, MLS, OSIRIS, POAM, …