Modeling the economic value of carbon sequestration by wetlands in the Delaware Estuary : historic estimates and future projections

© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Journal of Environmental Management 206 (2018): 40-50, doi:10.1016/j.jenvman.2017.10.018.Coastal wetlands sequester large amounts of carbon in their soils, effectively removing carbon dioxide from the atmosphere and acting as a carbon sink. In this paper, we estimate the economic value of carbon sequestered by wetlands in the Delaware Estuary. We estimate the value of the current stock of wetlands, the value of the historic loss of wetlands, and under a range of different scenarios the expected future loss. We use historical topographic maps and Land Cover inventories of the Delaware Estuary to measure the acreage of tidal wetlands in nine distinct time periods from 1778 to 2011. Using these data, we estimate an annual rate of wetland loss of 1.03km2. Coupling observed land cover change with exogenous factors including sea-level rise, population pressure, and channel dredging, we estimate changes in tidal wetland area under a range of future scenarios for our expected future economic loss estimates.This research is supported by NSF Coastal SEES Grant No. 1325136

Salinity intrusion in a modified river-estuary system: an integrated modeling framework for source-to-sea management

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Hoagland, P., Beet, A., Ralston, D., Parsons, G., Shirazi, Y., & Carr, E. Salinity intrusion in a modified river-estuary system: an integrated modeling framework for source-to-sea management. Frontiers in Marine Science, 7, (2020): 425, doi:10.3389/fmars.2020.00425.Along the US Atlantic and Gulf coasts, port authorities and governments have been competing for access to federal funds to deepen the channels and berths in each of the major estuary-based harbors, thereby facilitating access by larger containerships. Consistent with a source-to-sea conceptualization, physical modifications of an estuary can result in dynamic changes to its water and sediment flows, resulting in new arrangements of environmental features. These modifications, in turn, can lead to redistributions of the net benefits arising from extant flows of valued ecosystem services to stakeholders and communities in the broader river-estuary system. Here, some of the implications of channel deepening in the Hudson river-estuary system were examined as a case study. An integrated analytical framework was developed, comprising hydrodynamic models of water flows and environmental characteristics, especially salinity; extreme value estimates of the occurrence of regional droughts; and assessments of the welfare effects of changes in ecosystem services. Connections were found among channel deepening in the lower estuary, increased risks to fluvial drinking water withdrawals in the upper estuary, and expected economic losses to hydropower generation in the upper river. The results argue for a more inclusive consideration of the consequences of human modifications of river-estuary systems.This work was sponsored by NSF Coastal SEES Grant No. 1325136

Three essays on social cost elements of electricity generation and storage in the Mid-Atlantic region

Parsons, George R.Electricity generation and storage systems are experiencing dramatic shifts in the United States. Each decision underpinning these shifts involves a variety of complex trade-offs. From an economic welfare perspective, these trade-offs are described in terms of social costs and social benefits. Three essays presented in this dissertation explore aspects of social costs—and to a lesser extent social benefits—of electricity generation and storage technologies in the Mid-Atlantic region. While the social costs of mature technologies are generally well known, the social costs of emerging technologies or mature technologies in emerging environments have not been studied extensively. ☐ The first essay investigated the economics of vehicle-to-grid enabled electric school buses. This emerging storage technology was found to impose a variety of novel costs that have been frequently overlooked in the literature. Contrary to previous findings, a vehicle-to-grid enabled electric school bus was found to increase net present cost per seat relative to a conventional diesel bus. Vehicle-to-grid technology may become economically justifiable in future years contingent upon favorable technological, market and regulatory developments. ☐ A second essay investigated cost increases at a nuclear generating station from expected future salinity increases in the Delaware River and Estuary. This mature technology is projected to encounter an emerging operational environment as ambient water used for cooling increases in salinity from sea level rise and a deepened navigational channel. To estimate cost increases, a linked physical-economic model was developed to generate daily forecasts of ambient salinity under different future conditions and the resulting changes in the facility’s cooling water treatment and pumping requirements. On an equivalent annual basis (discounted at 5%), average cost increases were estimated as $0.4M per year. Methods developed here can be adapted to other estuarine facilities to estimate future cost increases under different salinity and operating regimes. ☐ The final essay investigated recreational impacts from offshore wind power projects by analyzing data from four in-person survey events. Respondents (n≈1500) were provided with simulated images of a large offshore wind project at different distances from shore and indicated if their beach enjoyment would have been made better or worse. In addition, respondents indicated whether they would have canceled their last beach trip due to the presence of the project at each distance. At policy relevant distances of 12.5 - 15 miles, mostly neutral and positive impacts to beach recreation were found. In addition, cancelation rates at these distances were generally under 10%. Trip cancelation rates varied significantly across surveys, suggesting responses may be sensitive to seemingly minor changes in survey format, wording and/or timing. ☐ These essays provide estimates and insights that can assist in identifying socially optimal electricity generation and storage systems. In addition, they illuminate ongoing uncertainties in the fields of vehicle-to-grid, salinity-induced cost increases to evaporatively cooled generating stations and visual impacts from offshore wind power.University of Delaware, School of Marine Science and PolicyPh.D