Emily Elliott - US grants

A US-Japan Joint Seminar in hydrology will be held has to foster exchange of ideas, bridge gaps in research approaches, and to jointly develop prospective research directions. Historically, there has been limited interaction among scientists between the two countries because language, culture, and research foci separate these scientific communities. These differences highlight a potential for scientific discovery and are the reasons for this US-Japan Joint Seminar in hydrology. The purpose of this forthcoming seminar is to expand the theme of linking hydrology and biogeochemistry to consider effects of climatic and environmental change, as well as emerging measurement and analytical techniques used in catchment science research that allow fundamental scientific advancements. The meeting will host approximately 20 scientists from each country, including students and early career scientists, to present and discuss cutting-edge research in catchment sciences in an open forum to foster collaboration and exchange. The seminar will focus on the following aspects of hydrological and biogeochemical catchment sciences: (1) the role of hydrologic connectivity in regulating carbon and nitrogen cycling and export from catchments in the face of climatic and environmental change; (2) synthesis and cross-site comparison along climatic gradients to understand mechanisms of solute yields from catchments; (3) advances in techniques (trace gas fluxes, isotopic mass balances) for balancing nutrient budgets and better understanding processes (denitrification, transport, uptake, mineralization, etc.); and (4) integrating field observations with theory to inform better model predictions

The US-Japan Joint Seminar will 1) foster interaction and develop new collaborative research between US and Japanese catchment scientists, 2) stimulate and engage the next generation of scientists who will become leaders in research and support future interaction between the two countries, and 3) advance understanding of how catchments respond to climatic and environmental changes. Cross-continental synthesis is a challenge, yet a necessity for determining how catchments will respond to global environmental change. To meet that challenge, the proposed multi-perspective seminar in catchment hydrology and forest biogeochemistry will bring together established researchers and early career scientists, providing invaluable opportunities for synthesis in catchment sciences.

This project seeks to improve the paleoclimate record and the broader scientific understanding of past and future hydrologic variability in the South Atlantic Gulf Basin (AGB) and Southeastern (SE) United States by carrying out a three-year research program to investigate pre-instrumental streamflow and associated climate variability in this region.

The principle goals of the research program are to develop quantitative, multi-century, tree-ring reconstructions and to assess the risk of future streamflow in the SE and AGB. The specific aims of this project are to 1) develop streamflow reconstructions for eight major, coastal, interstate rivers; 2) conduct inter-basin comparisons to identify spatial and temporal patterns of common and disparate streamflow variability across the region; 3) provide novel insights on how the dynamical modes of climate variability (e.g., El Nino-Southern Oscillation, the North Atlantic Sub-tropical High, and Atlantic Multidecadal Oscillation) force regional expressions of climate change, hydrological variability, extreme drought and pluvial events, and potential regime shifts over the past 500-1,000 years and 4) characterize the risk of future streamflow and extreme events in these watersheds.

This research will provide insight into not only the long-term variability of streamflow, but will also shed light on the associated physical, social, economic and ecological impacts this variability has on coastal watersheds in the AGB and SE US. Improved understanding of streamflow variability will directly benefit the development of water policy in SE, by informing a variety of socially and economically relevant areas related to water withdrawals, streamflow forecasts, drought and flood mitigation.

Recent work on the Suwannee River (Florida) provides a successful example of how streamflow in the Southeast can be reconstructed over multiple centuries with high variance explained (R2=0.68) and robust validation statistics (RE, 0.71; CE, 0.81), in addition to providing novel insight into the controls of past hydroclimate to characterize and manage the risk of future streamflow in the AGB and SE.

The potential Broader Impacts include the potential for enhanced understanding of both the history of hydroclimate variability (especially extreme low flow events) and the role of regional and large-scale climate forcing mechanisms that drive streamflow variability. This project seeks to provide information useful for applied risk management around hydrologic extremes in the South Atlantic Gulf Basin (AGB) and Southeastern (SE) United States region. Understanding the timing and magnitude of past events and having accurate future forecasting is crucial for public and private stakeholders to prepare for the future and increase resiliency. In addition, by characterizing past, present and future streamflow and the risk of extreme events in the AGB and SE watersheds, this research will advance knowledge of how to protect and sustain riparian zones, coastal watersheds and surrounding lands now and into the future.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

This project addresses the global challenge of rebalancing the nitrogen cycle by developing an innovative, sustainable technology to deliver nitrogen to crop roots more efficiently using minute spherical sacs called liposomes. The goal of the work is to use these liposomes as nitrogen carriers to reduce the amount of nitrogen that is added to farm fields and increase the percentage of nitrogen that is absorbed by the plant. The research is motivated by the immense environmental and human health costs associated with excess nitrogen use, including eutrophication in lakes and coastal waters, associated cyanotoxins produced by algal blooms, greenhouse gas emissions from production of nitrogen-based fertilizer, on-farm greenhouse gas emissions from nitrogen processes, and contaminated drinking water sources. The proposed technology is a holistic solution to address global food challenges by including sustainable and performance design criteria as well as considering the environmental impacts during the design and development stages. The proposed research aims to transform crop production from a net polluting system to a sustainable system and to align the needs of feeding society while protecting its prosperity.

The interdisciplinary team of engineers and scientists includes collective expertise in chemical processes, transport phenomena, transport of natural resources in Earth systems, sustainable material design, and systems analyses. The research leverages an emerging chemical process, continuous flow processing, to develop new liposome compositions that result in novel carriers for delivering nitrogen to crops. Isotopically labeled nitrogen-15 will illuminate partitioning and transport of the delivered nitrogen through soil-plant systems. Systems-level analysis will be integrated throughout the project to inform material choice, processing decisions, and feasibility assessment. Results from greenhouse studies will inform the nutrient carrier performance in terms of crop production and reducing leached nitrogen. These data will be used in a watershed model to project positive ecosystem impacts. The team will also develop initiatives that educate and train students across disciplinary silos in a convergent, collaborative environment through an interdisciplinary approach to mentoring, learning, and research. The research team will engage with stakeholders through the Pittsburgh Collaboratory for Water Research, Education, and Outreach, housed at the University of Pittsburgh (a network of over 100 governmental, non-governmental, advocacy, academic partner organizations, and over 300 individual water stakeholders), and the public through programming at the University of Pittsburgh’s field station, Pymatuning Lab of Ecology, in the Shenango River watershed.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2)

Improving the climate record of past tropical cyclone (TC) activity and related large-scale atmospheric driving mechanisms in the Southeast United States will advance knowledge and understanding of past TC characteristics and their mark left in the coastal environment. This project aims to develop a comprehensive multi-proxy database of tropical cyclone (TC) activity, including storm frequency and intensity throughout the last 150 years for northern Gulf of Mexico (nGoM) coastal systems. Specifically, the researchers will compare annually to seasonally resolved tree-ring records that act as TC proxies with lower resolution records of high intensity TC events recorded in sediment cores.

The project will develop a multi-proxy database of tropical cyclone occurrence for the nGoM by using existing, site-specific, well-calibrated sediment records of TCs in conjunction with instrumental and historical records of TC events to develop a 150-year record of TC events for each site in southeastern US. Additionally, particle size from established sediment records of TCs will be re-analyzed to model TC surge intensity over the 150-year period. The project will also develop annually resolved tree-ring records of TC activity for the Southeast by analyzing extant collections of multiple tree species (principally slash pine, longleaf pine, and bald cypress) that are known to be long-lived (~200–2,500 years), and are responsive to hydroclimatic variability, in multiple locations throughout the Southeast. The researchers will analyze various tracers including ring width and stable oxygen isotopes for a period of ~150 years to calibrate against the constrained TC chronology developed from sediment and instrumental records.

The potential Broader Impacts include the development and calibration of Tropical Cyclones (TCs) data set over the last 150 years for the northern Gulf of Mexico (nGoM). This data can be used to improve assessments of hazard impact, coastal ecosystem resiliency, and predictions of Tropical Cyclones. Coastal communities along the nGoM coast are at extreme risk in the light of projected climate change. Additionally, identifying geographic regions of greatest impact from TCs can inform local stakeholders on recent TC trends and the primary drivers, thus improving hurricane forecasts and response, and saving economic, cultural, and ecologically important resources. The results of the project will be disseminated to climate modelers, and to stakeholders, coastal managers, and policy makers to inform planning for TC damage from high winds, storm surge, and intense rainfall. Data developed from this research will be made publicly available. The project will support two early career researchers and will provide educational, research training and professional development opportunities for graduate and undergraduate students at University of Alabama Tuscaloosa.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.