Unlocking Past Ocean Circulation And Climate Changes Using Benthic Foraminifera

Chiara Borrelli, University of Rochester

The analysis of the chemical and isotopic composition of calcareous benthic foraminifera is a widely used approach to reconstruct changes in ocean circulation and climate through time. In the first part of the seminar, I will present the application of the “traditional” benthic foraminiferal oxygen and carbon isotope ratios to reconstruct ocean circulation changes in the North Atlantic during the greenhouse-icehouse transition, one of the most important climatic and oceanographic transitions of the last 50 million years. In addition, I will present microscopy and spectroscopy data revealing a novel biomineralization strategy in a particular foraminiferal species called Melonis barleeanus. In the second part of the talk, I will show some preliminary data regarding the development of novel approaches to study methane dynamics and biogeochemical cycles in marine sediments today and in the geological past. In particular, the “non- traditional” benthic foraminiferal hydrogen and sulphur isotope ratios look very promising for studying methane fluxes in marine sediments, whereas the investigation of the benthic foraminiferal S/Ca, Mn/Ca, and Fe/Ca can provide some insight on modern and past changes of the carbon, sulfur, manganese, and iron cycles as consequence of methane release, methane oxidation, and availability of dissolved oxygen in sediments.

4:00 PM - 5:00 PM

CO2 Levels And Climate Change During Early Eocene Hyperthermals

Ying Cui, Dartmouth College

Early Eocene (56 to 33.9 million years ago) is punctuated by a series of rapid and extreme global warming events, known as the ‘hyperthermals’, triggered by massive release of carbon dioxide. Despite the carbon emission rate might have been ten times smaller than the current emission from burning fossil fuels and cement production, the early Eocene hyperthermals are considered one of the best analogues for CO2 concentration projected into the future. The temperature records are well established from deep sea sediments during these hyperthermals, but the CO2 levels in the atmosphere remain poorly known, partly due to the lack of a reliable CO2 proxy.

Thanks to a newly developed C3 land plant CO2 proxy, we were able to calculate the upper limit of the CO2 levels just before and during five early Eocene hyperthermals (PETM, H1, H2, I1 and I2). This proxy is based on the empirical relationship between carbon isotope fractionation and the ambient CO2 levels: i.e. as CO2 level rises, carbon isotope fractionation also increases. By comparing the carbon isotope excursion recorded in the ocean and on land, we were able to find that CO2 levels just before each of the hyperthermals may have been less than 1000 parts per million, or ppm. CO2 level as high as 2600 ppm might have occurred only briefly during the hyperthermals. This suggests that to maintain the early Eocene ice-free condition and global average surface temperature of ~25 oC, other greenhouse gases, such as methane, water vapor and nitrous oxide must have played more important role.

4:00 PM - 5:00 PM

Understanding Abrupt Climate Change Over The Last 100,000 Years

Jennifer Hertzberg, Old Dominion University

Unlike the relatively stable climate Earth has experienced throughout the Holocene, Earth's climate system underwent a series of abrupt oscillations and reorganizations during the last glacial period and termination.

The first part of this seminar will investigate the trigger for the atmospheric CO2 rise that occurred during the last deglaciation, beginning 17,500 years ago. I will show that abrupt changes in the Atlantic Meridional Overturning Circulation occurring synchronously with the initial CO2 rise may have altered the oceanic biological pump, allowing CO2 to accumulate in the surface ocean and atmosphere. Records of surface and intermediate water foraminiferal δ13C suggest that the biological pump weakened as the overturning circulation slowed, which would have decreased the sequestration of carbon in the deep ocean.

In the second part of the seminar, I will present initial results of a newly funded project aimed at reconstructing tropical Pacific mean state and El Niño dynamics across the abrupt climate events of the last glacial period. Records of thermocline temperature and upwelling variability, reconstructed from foraminiferal Mg/Ca ratios and faunal analyses, respectively, suggest that abrupt warming events in the Eastern Pacific were characterized by warmer thermocline temperatures and decreased upwelling – conditions synonymous with an El Niño-like state. Both of these studies have important implications for future climate variability.

4:00 PM - 5:00 PM

10,000 Years of Ice Sheet Change in Baffin Bay

Nicolas Young, Lamont-Doherty Earth Observatory

The Greenland Ice Sheet (GrIS) is the largest ice mass in the Northern Hemisphere with a sea-level equivalent of 7.3 m and is expected to be a key contributor to 21st century (and beyond) sea-level rise. Estimates of GrIS-induced sea-level rise are dependent upon numerical ice-sheet models, but these models require some degree of “spin-up” or tuning to test model validity before forward modeling can commence. Within this framework, well-constrained geological records of GrIS change provide important spatial and temporal benchmarks for which to test numerical ice-sheet models. Of particular interest is reconstructing and modeling the behavior of the GrIS through the Holocene because this time period includes 1) abrupt cooling cooling events occurring on human-relevant timescales, and 2) the most recent interval of regional warmer-than-present temperatures. Thus, accurate geological and model-based reconstructions of southwestern GrIS behavior during the Holocene have clear relevance for predicting future GrIS change in response to potential freshwater induced regional cooling, and for assessing the GrIS’s contribution to eustatic sea-level rise in an overall warming world. Here, I use several approaches to precisely reconstruct the behavior of the southwestern GrIS through the Holocene – emphasizing the response of the GrIS to early Holocene abrupt cooling, and the minimum extent of the GrIS during the Holocene thermal maximum. In addition, I will draw on emerging datasets from across Baffin Bay that constrain the behavior of the Laurentide Ice Sheet through the Holocene. Combined, records from Greenland and eastern Canada suggests that ice sheets are capable of dramatic responses to extremely short-lived climate perturbations.

4:00 PM - 5:00 PM

Ecosystem Engineering, Anthropogenic Landscapes, and Sea Level Changes Over 8000 Years of Human History in the Eastern Caribbean

Peter E. Siegel, Montclair State University

Upon first arrival of humans to new places anthropogenic disturbances to landscapes commence. Later groups of different people or descendants of the original colonists will make yet additional modifications and so on through time, so that by today the landscape contains a cumulative record of anthropogenic history. We combined the interpretive frameworks of landscape and historical ecology to investigate the anthropogenic trajectories across nine islands of the southern and eastern Caribbean. Microfossils from a series of environmental cores reveal the shifting and cumulative humanization of landscapes from c. 8000 cal yr BP through early European colonial occupations in this region.

4:00 PM - 5:00 PM

Using Natural Resources to Control the Fate of Contaminants in the environment

Lucia Rodriguez Freire, New Jersey Institute of Technology

Environmental contamination poses an increased health risk to those communities living nearby impacted sites, and it is imperative to find sustainable remediation strategies to restore the natural systems. My research investigates natural biogeochemical processes and the use of ubiquitous materials to the design remediation solutions that are site-specific and take into consideration the needs of the affected communities. The first example is the investigation of uranium (U) accumulation in plants growing along the Rio Paguate, which flows through the Jackpile Mine, and open-pit U mine listed on the National Priority List as a Superfund site. Two villages of the Laguna Pueblo in New Mexico are in the vicinities of Jackpile Mine. Salt cedar plants showed U accumulation in their roots ranging from 25.2 – 58.9 mg kg-1. Microscopy and spectroscopy analyses of roots indicates that U appears to be entrapped in the cell walls in the roots. This preferable binding of U to the root cell walls may explain the U weak translocation toward salt cedars leaves. The second example is the response to the Gold King Mine spill that released a mixture of metals in the Animas River in southern Colorado. The Animas River flows from a heavily mineralized area (San Juan Mountain, Colorado) to an intensive agricultural area (Farmington, New Mexico), home of the Navajo Agricultural and Product Industry. Sediment samples collected 2 weeks after the spill showed lead, copper and zinc associated with clays, iron-(oxy)hydroxides, and jarosite.. Jarosite solubility at near-neutral pH and biogeochemical processes occurring downstream affect the remobilization of metals in sediments. This work has unique implications to better understand the delicate equilibrium of metals and surface water, sediments and plants downstream mine waste. This information is essential for determining the potential for metals exposure and to inform remediation strategies.

4:00 PM - 5:00 PM

Emergency Water Supply in Response to Natural Disasters

Yang Deng, Montclair State University

Frequency and magnitude of natural disasters (e.g. hurricanes) increased globally over the past century. Clean water is a top priority for disaster-affected populations. However, existing emergency water treatment (EWT) methods are not all feasible or technically effective at many emergency situations. The recent Puerto Rican water crisis after Hurricane Maria highlights research needs and new challenges for new EWT technologies. This presentation will provide an overview of currently available EWT methods and then introduce the state of EWT research at MSU. Ferrate(VI) as an emerging treatment agent was recently investigated for the treatment of simulated disaster- polluted water. Results show that ferrate(VI) treatment could simultaneously and effectively inactivate bacterial indicators, remove metal and metalloid contaminants, degrade dissolved organic matters, and reduce turbidity, while insignificantly increasing total dissolved solids (TDS) to ensure an acceptable TDS ≤ 1,000 mg/L (the recommended minimum TDS standard for emergency water supply). Different from many traditional water treatment agents (e.g. chlorine), ferrate(VI) does not produce toxic disinfection byproducts (DBPs). Therefore, ferrate(VI) opens a new opportunity for EWT to provide safe and sufficient water for disaster-affected populations and rapid disaster relief.

4:00 PM - 5:00 PM

Is there a Home for Agroforestry in Nutrient Credit Trading?

John Munsell, Virginia Tech

Agroforestry riparian buffers and upslope contour plantings provide environmental and economic benefits without eliminating annual farming opportunities. A public/private partnership in Virginia is leading a project titled Conservation Credit for Agroforestry Production (C-CAP) to study the potential for agroforestry to generate profitable credits in private nutrient trading markets. Phosphorus and nitrogen delivered to stream edges are modeled across a sample of agroforestry project sites. Results are being studied to determine financial profitability and relationships to Total Maximum Daily Loads. Research is also being conducted on tree-tube effectiveness, site preparation strategies, plant-water relations on contour, nitrogen fixer intercropping, and financial risk. This presentation will cover C-CAP initiatives, discuss challenges for trading using agroforestry farming, and outline intentions for scaling results to estimate benefits across different agroforestry adoption rates at the landscape-level.

4:00 PM - 5:00 PM

Planning for Healthy Ecosystems and Sustainable Human Use in the Mid-Atlantic Ocean

Tony Macdonald, Monmouth University

The seminar will focus on how coastal and marine sustainability issues in the Mid-Atlantic have been addressed through regional ocean planning and marine spatial planning. The Mid-Atlantic Regional Council on the Ocean (MARCO) was established in 2009 to enhance the vitality of the region's ocean ecosystem and economy. Obama Administration established an Ocean Policy Task Force and signed an Executive Order on July 19, 2010 adopting the Final Recommendations of the Task Force, establishing a National Policy for the Stewardship of the Ocean, Coasts, and Great Lakes, and calling for the development of regional coastal and marine spatial plans.

MARCO’s first action items was the development of the Mid-Atlantic Ocean Data Portal to serve as an on-line platform to engage stakeholders across the region with the objective of improving their understanding of how ocean resources and places are being used, managed, and conserved. Monmouth University Urban Coast Institute served as the principal investigation in working with MARCO and other partner in development of the Ocean Data Portal.

4:00 PM - 5:00 PM

A Substance Flow Model for Global Phosphorus

David A. Vaccari, Stevens Institute of Technology

A mechanistic model of phosphorus flows through the global food system was developed to address questions about the relative effectiveness of and interactions among potential conservation interventions. Phosphorus is required as a fertilizer for producing food, and there is no substitute. Most phosphorus used in agriculture is mined, and 75% of the world’s reserves are controlled by a single country: Morocco. Thus the world’s food supply is potentially vulnerable to geopolitical conditions. Although known reserves can satisfy current demand for several centuries, it is nevertheless the case that an essential resource is being used unsustainably. Only about 10% of the phosphorus used in agriculture reaches our plates. Losses along the way contribute to water pollution, causing eutrophication. In freshwater bodies this produces toxic drinking water and fish kills. In the coastal marine environment eutrophication causes hypoxic (low oxygen) zones, popularly called “dead zones, in many parts of the world. Thus conservation of phosphorus is of interest both to preserve the resource and to prevent pollution.

The conservation interventions considered include: population control; reduction in meat fraction in the diet (MFD); animal manure use efficiency (MUE); agricultural phosphorus use efficiency (PUE); the fraction of food supply that is wasted; the fraction of food waste that is recycled; the fraction of human waste that is recycled. The model shows that the meat fraction in the diet is the most sensitive of these factors, and this factor interacts with PUE and MUE. Furthermore, there is a minimum MFD below which it actually becomes necessary to mine more phosphorus. Another conclusion is that recycling is much less effective than reduction in conserving the resource.

4:00 PM - 5:00 PM

Heterogeneous Photo-Fenton Reactions and Hybridization with Ceramic Membrane Filtration

Wen Zhang, New Jersey Institute of Technology

4:00 PM - 5:00 PM

Dry Powder Intranasal Oxytocin for Treatment of Postpartum Hemorrhage in the Developing World

Adrian Goodey, Merck Research Laboratories

Complications related to pregnancy and child birth claim nearly 800 women’s lives each day. This tragedy is compounded by the fact that the vast majority of these deaths are preventable. However, ninety-nine percent of maternal deaths occur in the developing world where basic medical services and supplies are typically scarce. Postpartum hemorrhage (PPH; excessive bleeding after child birth), accounts for nearly 25% of maternal deaths globally, and is an especially acute concern in resource-scarce settings. The pharmacological treatment recommended for PPH by the World Health Organization, oxytocin, is incompatible with regions where reliable refrigeration is unavailable. Typically formulated as an aqueous solution for injection, oxytocin rapidly loses efficacy at room temperature via chemical degradation. In the present work, we explore the feasibility of adapting oxytocin from its standard injectable solution form to a dry powder formulation for intranasal administration. A preclinical evaluation reveals an impressive 12% bioavailability (relative to intramuscular injection) with sufficiently rapid onset for treatment of PPH. Moreover, in-vitro characterization confirmed good physical and chemical stability, offering hope that dry powder oxytocin formulations for intranasal delivery may be a viable option for treatment of PPH in the developing world.

4:00 PM - 5:00 PM

Exploiting Synchrotron “Light” to Study Chemistry of Trace Elements in Soils and Plants

Ryan Tappero, Brookhaven National Laboratory

Biogeochemical studies often require characterization of elemental abundances and speciation in samples that are chemically and physically heterogeneous at the micrometer scale. Synchrotron radiation sources are ideal for developing high intensity, highly-focused X-ray probes for interrogating the speciation, transport, and reactions of trace elements in heterogeneous earth and biological materials with detection sensitivities in the attogram range and spatial resolutions less than 1 micrometer.

X-ray Fluorescence Microprobe (XFM) is a new, multi-modal X-ray fluorescence microscope recently installed at the National Synchrotron Light Source-II (NSLS-II) at Brookhaven National Laboratory. XFM has capabilities for X- ray micro-fluorescence (μ-XRF) imaging and tomography, X-ray absorption spectroscopy (μ-XAS), and X-ray microdiffraction (μ-XRD). Micro-XRF allows one to image and quantify the distribution of trace elements in heterogeneous samples. Micro-XAS analysis allows one to interrogate oxidation state and chemical speciation of the trace elements. Coupled XRF-, XAS-, XRD- microanalysis allows one to quantify the abundance and speciation of elements at trace concentrations and evaluate the mineralogy to which they are adsorbed or bound in soil. Such information is crucial in understanding the toxicity, mobility and containment of toxic metals in the environment and the mechanisms of nutrient uptake and partitioning in plants. Examples will be given of how these instruments are applied in the Plant and Soil Sciences.

4:00 PM - 5:00 PM

Magmatism and Mass Extinction: Resolving the Flood Basalt Carbon Quandary

Benjamin Black, The City University of New York

Voluminous flood basalt magmatism has coincided with multiple biotic crises, including the end-Permian, end-Triassic, and end-Cretaceous mass extinctions and the Paleocene-Eocene Thermal Maximum. Geochemical evidence shows that warming and carbon cycle perturbation were features of each of these events. This proxy evidence is at odds with current estimates of the budget and isotopic composition of carbon in flood basalt magmas, which suggest that flood basalt magmatic carbon is inadequate and too isotopically heavy to explain the observations. To address the apparent conflict between paleoclimate and petrology, I present results from melt inclusions, carbonatites, geophysical modeling, and climate modeling to address hypotheses including metamorphic release of crustal carbon and upward revision of the magmatic carbon budget. Intervals of extreme stress during past flood basalt eruptions carry a range of implications for Earth’s near-future climate systems.

4:00 PM - 5:00 PM

Quantifying Transport of Passive Tracers and Inertial Particles in Geophysical Flows

Eric Forgoston, Montclair State University

There has been a steady increase in the deployment of autonomous underwater and surface vehicles for applications such as ocean monitoring, tracking of marine processes, and forecasting contaminant transport. The underwater environment poses unique challenges since robots must operate in a communication and localization-limited environment where their dynamics are tightly coupled with the environmental dynamics. This work presents current efforts in understanding the impact of geophysical fluid dynamics on underwater vehicle control and autonomy. The focus of the first part of the talk is on the control of collaborative vehicles to track Lagrangian coherent structures and to localize contaminant spills. In the second part of the talk, the focus is on the investigation of the dynamics of inertial particles in geophysical flows which include the Coriolis force.

4:00 PM - 5:00 PM