Oceanography and Atmospheric Sciences and Meteorology Commons^™

Agenda, Hr Adaptation Forum

February 18, 2016: Cultural Institutions Reaching Out to Residents

No abstract provided.

Effects Of Elevated Pco2 And Irradiance On Growth, Photosynthesis And Calcification In Halimeda Discoidea, K. E. Peach, M. S. Koch, Patricia Blackwelder

Marine & Environmental Sciences Faculty Articles

Ocean acidification (OA) effects on photophysiology and calcification were examined in Halimeda discoidea, a calcifying macroalga that produces tropical reef sediments. Photosynthetic parameters, including maximum photosynthetic rate (P_max), photosynthetic efficiency (α) and compensating irradiance (I_c) were determined in short-term assays on live thalli after a 10 d exposure to 4 levels of CO₂ partial pressures (pCO₂; 491, 653, 982 and 1201 µatm) under saturating (300 µmol photons m^-2 s^-1) and sub-saturating (90 µmol photons m^-2 s^-1) irradiance in an aquaria study. Morphology …

Predicting Dissolved Lignin Phenol Concentrations In The Coastal Ocean From Chromophoric Dissolved Organic Matter (Cdom) Absorption Coefficients, Cédric G. Fichot, Ronald Benner, Karl Kaiser, Yuan Shen, Rainer M. W. Amon, Hiroshi Ogawa, Chua-Jung Lu

Faculty Publications

Dissolved lignin is a well-established biomarker of terrigenous dissolved organic matter (DOM) in the ocean, and a chromophoric component of DOM. Although evidence suggests there is a strong linkage between lignin concentrations and chromophoric dissolved organic matter (CDOM) absorption coefficients in coastal waters, the characteristics of this linkage and the existence of a relationship that is applicable across coastal oceans remain unclear. Here, 421 paired measurements of dissolved lignin concentrations (sum of nine lignin phenols) and CDOM absorption coefficients [ag(λ)] were used to examine their relationship along the river-ocean continuum (0–37 salinity) and across contrasting coastal oceans (sub-tropical, temperate, high-latitude). …

On The Nature Of The Frontal Zone Of The Choctawhatchee Bay Plume In The Gulf Of Mexico, K. D. Huguenard, D. J. Bogucki, D. G. Ortiz-Suslow, N. J. M. Laxague, J. H. Macmahan, T. M. Ozgokmen, Brian K. Haus, A. J. H. M. Reniers, J. Hargrove, Alexander Soloviev, H. Graber

Marine & Environmental Sciences Faculty Articles

River plumes often feature turbulent processes in the frontal zone and interfacial region at base of the plume, which ultimately impact spreading and mixing rates with the ambient coastal ocean. The degree to which these processes govern overall plume mixing is yet to be quantified with microstructure observations. A field campaign was conducted in a river plume in the northeast Gulf of Mexico in December 2013, in order to assess mixing processes that could potentially impact transport and dispersion of surface material near coastal regions. Current velocity, density, and Turbulent Kinetic Energy Values, ε, were obtained using an Acoustic …

Effect Of The North Equatorial Counter Current On The Generation And Propagation Of Internal Solitary Waves Off The Amazon Shelf (Sar Observations), Jorge Manuel Magalhães, J.C.B. Da Silva, Maarten C. Buijsman, Carlos A.E. Gaercia

Faculty Publications

. Synthetic aperture radar (SAR) imagery from the Amazon shelf break region in the tropical west Atlantic reveals for the first time the two-dimensional horizontal structure of an intense Internal Solitary Wave (ISW) field, whose first surface manifestations are detected several hundred kilometres away from the nearest forcing bathymetry. Composite maps and an energy budget analysis (provided from the Hybrid Coordinate Ocean Model – HYCOM) help to identify two major ISW pathways emanating from the steep slopes of a small promontory (or headland) near 44◦ W and 0 ◦ N, which are seen to extend for over 500 km into …

Virginia's Leadership In The Race Against Sea-Level Rise, Paul Olsen

News Items

No abstract provided.

Water Balance Monitoring For Two Bioretention Gardens In Omaha, Nebraska, 2011–14, Kellan R. Strauch, David L. Rus, Kent E. Holm

United States Geological Survey: Water Reports and Publications

Document abstract

Bioretention gardens are used to help mitigate stormwater runoff in urban settings in an attempt to restore the hydrologic response of the developed land to a natural predevelopment response in which more water is infiltrated rather than routed directly to urban drainage networks. To better understand the performance of bioretention gardens in facilitating infiltration of stormwater in eastern Nebraska, the United States Geological Survey (USGS), in cooperation with the Douglas County Environmental Services and the Nebraska Environmental Trust, assessed the water balance of two bioretention gardens located in Omaha, Nebraska by monitoring the amount of stormwater entering and …

Sediment Loads And Transport At Constructed Chutes Along The Missouri River-Upper Hamburg Chute Near Nebraska City, Nebraska, And Kansas Chute Near Peru, Nebraska, Brenda K. Densmore, David L. Rus, Matthew T. Moser, Brent M. Hall, Michael J. Andersen

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS), in cooperation with the United States Army Corps of Engineers, monitored suspended sediment within constructed Missouri River chutes during March through October 2012. Chutes were constructed at selected river bends by the US Army Corps of Engineers to help mitigate aquatic habitat lost through the creation and maintenance of the navigation channel on the Missouri River. The restoration and development of chutes is one method for creating shallow-water habitat within the Missouri River to meet requirements established by the amended 2000 Biological Opinion. Understanding geomorphic channel-evolution processes and sediment transport is important for the …

Long-Term Trend Analysis Of Precipitation And Air Temperature For Kentucky, United States, Somsubhra Chattopadhyay, Dwayne R. Edwards

Biosystems and Agricultural Engineering Faculty Publications

Variation in quantities such as precipitation and temperature is often assessed by detecting and characterizing trends in available meteorological data. The objective of this study was to determine the long-term trends in annual precipitation and mean annual air temperature for the state of Kentucky. Non-parametric statistical tests were applied to homogenized and (as needed) pre-whitened annual series of precipitation and mean air temperature during 1950–2010. Significant trends in annual precipitation were detected (both positive, averaging 4.1 mm/year) for only two of the 60 precipitation-homogenous weather stations (Calloway and Carlisle counties in rural western Kentucky). Only three of the 42 temperature-homogenous …

Agriculture Causes Nitrate Fertilization Of Remote Alpine Lakes, Elizabeth J. Hundey, Sam S.D. Russell, Fred Longstaffe, Katrina A. Moser

Earth Sciences Publications

Humans have altered Earth’s nitrogen cycle so dramatically that reactive nitrogen (Nr) has doubled. This has increased Nr in aquatic ecosystems, which can lead to reduced water quality and ecosystem health. Apportioning sources of Nr to specific ecosystems, however, continues to be challenging, despite this knowledge being critical for mitigation and protection of water resources. Here we use D¹⁷O, d¹⁸O and d¹⁵N from Uinta Mountain (Utah, USA) snow, inflow and lake nitrate in combination with a Bayesian-based stable isotope mixing model, to show that at least 70% of nitrates in aquatic systems are anthropogenic …

Spectral Sensitivity, Spatial Resolution And Temporal Resolution And Their Implications For Conspecific Signalling In Cleaner Shrimp, Eleanor M. Caves, Tamara M. Frank, Sonke Johnsen

Marine & Environmental Sciences Faculty Articles

Cleaner shrimp (Decapoda) regularly interact with conspecifics and client reef fish, both of which appear colourful and finely patterned to human observers. However, whether cleaner shrimp can perceive the colour patterns of conspecifics and clients is unknown, because cleaner shrimp visual capabilities are unstudied. We quantified spectral sensitivity and temporal resolution using electroretinography (ERG), and spatial resolution using both morphological (inter-ommatidial angle) and behavioural (optomotor) methods in three cleaner shrimp species: Lysmata amboinensis,Ancylomenes pedersoni and Urocaridella antonbruunii. In all three species, we found strong evidence for only a single spectral sensitivity peak of (mean±s.e.m.) 518±5, 518±2 and …

Hpcnmf: A High-Performance Toolbox For Non-Negative Matrix Factorization, Karthik Devarajan, Guoli Wang

COBRA Preprint Series

Non-negative matrix factorization (NMF) is a widely used machine learning algorithm for dimension reduction of large-scale data. It has found successful applications in a variety of fields such as computational biology, neuroscience, natural language processing, information retrieval, image processing and speech recognition. In bioinformatics, for example, it has been used to extract patterns and profiles from genomic and text-mining data as well as in protein sequence and structure analysis. While the scientific performance of NMF is very promising in dealing with high dimensional data sets and complex data structures, its computational cost is high and sometimes could be critical for …

Can The Gulf Stream Induce Coherent Short-Term Fluctuations In Sea Level Along The Us East Coast?: A Modeling Study, Tal Ezer

CCPO Publications

Much attention has been given in recent years to observations and models that show that variations in the transport of the Atlantic Meridional Overturning Circulation (AMOC) and in the Gulf Stream (GS) can contribute to interannual, decadal, and multi-decadal variations in coastal sea level (CSL) along the US East Coast. However, less is known about the impact of short-term (time scales of days to weeks) fluctuations in the GS and their impact on CSL anomalies. Some observations suggest that these anomalies can cause unpredictable minor tidal flooding in low-lying areas when the GS suddenly weakens. Can these short-term CSL variations …

Measuring The Seeds Of Ion Outflow: Auroral Sounding Rocket Observations Of Low-Altitude Ion Heating And Circulation, P. A. Fernandes, K. A. Lynch, M. Zettergren, D. L. Hampton, T. A. Bekkeng, Et Al.

Publications

We present an analysis of in situ measurements from the MICA (Magnetosphere-Ionosphere Coupling in the Alfvén Resonator) nightside auroral sounding rocket with comparisons to a multifluid ionospheric model. MICA made observations at altitudes below 325 km of the thermal ion kinetic particle distributions that are the origins of ion outflow. Late flight, in the vicinity of an auroral arc, we observe frictional processes controlling the ion temperature. Upflow of these cold ions is attributed to either the ambipolar field resulting from the heated electrons or possibly to ion-neutral collisions. We measure convection away from the arc (poleward) and downflows of …

A Preliminary Assessment Of Gpm-Based Multi-Satellite Precipitation Estimates Over A Monsoon Dominated Region, Satya Prakash, Ashis K. Mitra, Amir Aghakouchak, Zhong Liu, Hamidreza Norouzi, D. S. Pai

Publications and Research

Following the launch of the Global Precipitation Measurement (GPM) Core Observatory, two advanced high resolution multi-satellite precipitation products namely, Integrated Multi-satellitE Retrievals for GPM (IMERG) and Global Satellite Mapping of Precipitation (GSMaP) version 6 are released. A critical evaluation of these newly released precipitation data sets is very important for both the end users and data developers. This study provides a comprehensive assessment of IMERG research product and GSMaP estimates over India at a daily scale for the southwest monsoon season (June to September 2014). The GPM-based precipitation products are inter-compared with widely used TRMM Multi-satellite Precipitation Analysis (TMPA), and …

Improved Viirs And Modis Sst Imagery, Irina Gladkova, Alexander Ignatov, Fazlul Shahriar, Yury Kihai, Don Hillger, Boris Petrenko

Publications and Research

Moderate Resolution Imaging Spectroradiometers (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) radiometers, flown onboard Terra/Aqua and Suomi National Polar-orbiting Partnership (S-NPP)/Joint Polar Satellite System (JPSS) satellites, are capable of providing superior sea surface temperature (SST) imagery. However, the swath data of these multi-detector sensors are subject to several artifacts including bow-tie distortions and striping, and require special pre-processing steps. VIIRS additionally does two irreversible data reduction steps onboard: pixel aggregation (to reduce resolution changes across the swath) and pixel deletion, which complicate both bow-tie correction and destriping. While destriping was addressed elsewhere, this paper describes an algorithm, adopted in …

Evidence Of Dispersion And Refraction Of A Spectrally Broad Gravity Wave Packet In The Mesopause Region Observed By The Na Lidar And Mesospheric Temperature Mapper Above Logan, Utah, Tao Yuan, Christopher J. Heale, Jonathan B. Snively, Xuguang Cai, Pierre-Dominique Pautet, C. Fish, Yucheng Zhao, Michael J. Taylor, William R. Pendleton Jr., V. Wickwar, Nicholas John Mitchell

Publications

Gravity wave packets excited by a source of finite duration and size possess a broad frequency and wave number spectrum and thus span a range of temporal and spatial scales. Observing at a single location relatively close to the source, the wave components with higher frequency and larger vertical wavelength dominate at earlier times and at higher altitudes, while the lower frequency components, with shorter vertical wavelength, dominate during the latter part of the propagation. Utilizing observations from the Na lidar at Utah State University and the nearby Mesospheric Temperature Mapper at Bear Lake Observatory (41.9°N, 111.4°W), we investigate a …

Evidence Of Dispersion And Refraction Of A Spectrally Broad Gravity Wave Packet In The Mesopause Region Observed By The Na Lidar And Mesospheric Temperature Mapper Above Logan, Utah, T. Yuan, C. J. Heale, J. B. Snively, X. Cai, P.- D. Pautet, C. Fish, Y. Zhao, M. J. Taylor, W. R. Pendleton Jr., V. Wickwar, N. J. Mitchell

Publications

"Gravity wave packets excited by a source of finite duration and size possess a broad frequency and wave number spectrum and thus span a range of temporal and spatial scales. Observing at a single location relatively close to the source, the wave components with higher frequency and larger vertical wavelength dominate at earlier times and at higher altitudes, while the lower frequency components, with shorter vertical wavelength, dominate during the latter part of the propagation. Utilizing observations fromthe Na lidar at Utah State University and the nearby Mesospheric Temperature Mapper at Bear Lake Observatory (41.9°N, 111.4°W), we investigate a unique …

Relationships Between Wind Predictions And Model Resolution Over Coastal Regions, Mustafa Kemal Cambazoglu, Cheryl Ann Blain, Travis A. Smith, Robert S. Linzell

Faculty Publications

The impact of resolution on wind predictions within regions of complex coastal geometry is evaluated using a quadruple nest of COAMPS^® (27 km to 1 km) to find an optimal configuration of spatial and temporal resolution. Two regions, Turkish Straits System and Chesapeake Bay, are selected because of their diverse coastal environments, the availability of wind observations and to determine if the relationships between resolution and wind prediction accuracy would be valid for geographically different regions. The coarse resolution model successfully simulates the general trend of the surface wind variation, but cannot capture peak events accurately. Increased spatial resolution …

Retrival Of Atmospheric Aerosol Size Distributions Using Stochastic Particle Swarm Optimization, Benjamin D. Nault-Maurer

All College Thesis Program, 2016-2019

A stochastic particle swarm optimization (SPSO) technique’s robustness is studied in regards to atmospheric aerosol size distribution estimations for a bimodal distribution that focuses on Aitken and accumulation mode aerosols. The SPSO method is used to calculate a set of 11 aerosol optical depth (AOD) values based on a size distribution and match them to an inputted set of AOD values. This method is tested using computer generated AOD values with fixed distribution parameters, generated AOD values with varying distribution parameters, two sets of AOD measurements in clear conditions, and one set of AOD values in hazy conditions. The SPSO …

Super-Oceanic Winds Over A Narrow Coastal Estuary In Onshore Flow Events, Michael Splitt, Steven M. Lazarus, Jeff Colvin, Bryan P. Holman

Ocean Engineering and Marine Sciences Faculty Publications

Indian River Lagoon Winds -- Shallow water estuary -- Average depth ~ 1 m -- Fetch limited except NNW/SSE -- Stretches 150 miles north/south -- Limited exchange with ocean via inlets -- Improvement of wind forcing -- Wind set-up and surge forecasting -- Significant wave height forecasting -- “cheaper” solutions for ensemble forecasts -- Protection of life & property (NWS) -- Ecological system impacts (local science)

Forecasting Significant Wave Height In A Coastal Estuary, Steven M. Lazarus, Michael Splitt, Jeff Colvin, Bryan Holman, Robert Weaver, Peyman Taeb, Atousa Saberi

Ocean Engineering and Marine Sciences Faculty Publications

Would like to ‘extend’ the Nearshore Wave Prediction System (NWPS, Van Der Westhuysen et al. 2013) into a large narrow estuary (Indian River Lagoon, IRL). Full-blown hydrodynamic simulations

Impacts Of Bias Correction Of Wind Forecasts On Hydrodynamic And Wave Model Predictions, Robert J. Weaver, Peyman Taeb, Bryan P. Holman, Steven M. Lazarus, Michael E. Splitt, Atousa Saberi, Jeff Colvin

Ocean Engineering and Marine Sciences Faculty Publications

High-resolution hydrodynamic models are forced by surface wind output from operational met. models. Current suite of operational met. models do not have the spatial resolution needed to resolve the fine scale processes associated with complex estuarine wind-driven circulation nor a detailed land-water mask. Goal: improve forecast wind forcing in most efficient manner as possible

Surfactant-Associated Bacteria In The Near-Surface Layer Of The Ocean, Naoko Kurata, Katie E. Vella, Bryan Hamilton, Mahmood S. Shivji, Alexander Soloviev, Silvia Matt, Aurelien Tartar, William Perrie

Marine & Environmental Sciences Faculty Articles

Certain marine bacteria found in the near-surface layer of the ocean are expected to play important roles in the production and decay of surface active materials; however, the details of these processes are still unclear. Here we provide evidence supporting connection between the presence of surfactant-associated bacteria in the near-surface layer of the ocean, slicks on the sea surface, and a distinctive feature in the synthetic aperture radar (SAR) imagery of the sea surface. From DNA analyses of the in situ samples using pyrosequencing technology, we found the highest abundance of surfactant-associated bacterial taxa in the near-surface layer below the …

Propagation Of Drought: From Meteorological Drought To Agricultural And Hydrological Drought, Wen Wang, Maurits W. Ertsen, Mark D. Svoboda, Mohsin Hafeez

National Drought Mitigation Center: Faculty Publications

Drought is a hazard that occurs everywhere in the world (both in dry and in wet areas). Despite the controversy regarding drought changes in the last decades [1–3], increases in drought intensity are clearly identified in some areas [4] and it is believed that although increased heating from global warming may not directly cause droughts, it is expected that when droughts occur, they are likely to set in quicker and be more intense [5].

Throughout its history, China has frequently suffered from drought disasters due to its monsoon climate and was regularly hit hard by droughts over the last decades. …

New Metric For Defining The Time Of Extratropical Transition Of Tropical Cyclones, Ajay Raghavendra, Shawn M. Milrad

Publications

Almost half of all tropical cyclones (TCs) in the Atlantic basin undergo extratropical transition (ET). During an ET event, wind fields often expand dramatically, resulting in more widely-felt impacts. Moreover, the heaviest precipitation typically shifts to the left-of-center (LOC), which can result in inland flash flooding hundreds of kilometers from the cyclone center. While several objective metrics to track and predict ET have been developed, they rely at least partially on internal tropical cyclone structure, for which numerical models show less skill. Further, these metrics fail to account for static stability, which plays a vital role in determining precipitation amounts. …

Community Conversation About Sea Level Rise Continues At Odu-Hosted Resilience Forum, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

U.S. Secretary Of State Kerry Lauds Odu Initiatives During Climate Change Address, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.

Influence Of Sea Ice On Arctic Precipitation, Ben G. Kopec, Xiahong Feng, Fred A. Michel, Eric S. Posmentier

Dartmouth Scholarship

Global climate is influenced by the Arctic hydrologic cycle, which is, in part, regulated by sea ice through its control on evaporation and precipitation. However, the quantitative link between precipitation and sea ice extent is poorly constrained. Here we present observational evidence for the response of precipitation to sea ice reduction and assess the sensitivity of the response. Changes in the proportion of moisture sourced from the Arctic with sea ice change in the Canadian Arctic and Greenland Sea regions over the past two decades are inferred from annually averaged deuterium excess (d-excess) measurements from six sites. Other influences on …

Analysis Of The Precipitation Detection Algorithm For The Geonor T-200b Precipitation Gauge To Improve Accuracy, Megan Lerman, Robert K. Goodrich

STAR Program Research Presentations

In an effort to improve the precipitation detection algorithm for the Geonor All Weather Precipitation Gauge, an automated truth algorithm has been created to detect errors in the original algorithm. The original algorithm detects precipitation in real time and uses the rate of precipitation to indicate an event. The automated truth does not detect in real time, and focuses on precipitation accumulation to indicate an event. Since the automated truth is delayed, it is able to consider the data collected before and after the point it is analyzing. The automated truth is already more accurate than the original algorithm but …