Glenn Guntenspergen, Ph.D.
Science and Products
The Response of Coastal Wetlands to Sea-level Rise: Understanding how Macroscale Drivers Influence Local Processes and Feedbacks
The purpose of this work is to advance our understanding of how coastal wetland responses to sea-level rise (SLR) within the conterminous United States are likely to vary as a function of local, regional, and macroscale drivers, including climate. Based on our interactions with managers and decision makers, as well as our knowledge of the current state of the science, we propose to: (a)...
The response of coastal wetlands to sea-level rise: Understanding how macroscale drivers influence local processes and feedbacks
The purpose of this work is to advance our understanding of how coastal wetland responses to SLR within the conterminous United States are likely to vary as a function of local, regional, and macroscale drivers, including climate. Based on our interactions with managers and decision makers, as well as our knowledge of the current state of the science, we propose to (a) conduct a national...
Sea-level Rise
Acceleration in sea-level rise and changing environmental stressors have important implications for the integrity of coastal wetlands and for efforts to restore and protect the ecosystem services they provide. Federal and state agencies need to make more detailed assessments of how different watersheds and shoreline types might influence an array of ecosystem functions and components and...
Development of a Multimetric Index for Integrated Assessment of Salt Marsh Condition in the Northeast Coastal and Barrier Network
Salt marsh ecosystems along all US coastlines have been altered, degraded, and destroyed by human activities, including ditching and drainage of the marsh platform, tidal restrictions, discharge of pollutants, and introduction of invasive species. The National Park Service conducts long-term monitoring of salt marsh vegetation and nekton (fish and free-swimming crustaceans) to provide...
Improving Our Ability to Forecast Tidal Marsh Response to Sea Level Rise
Our overall objective is to understand what controls the vulnerability of coastal marshes to risks associated with global change drivers and rising sea levels. Fundamental questions pertaining to coastal wetland vulnerability still need to be addressed. What factors explain spatial and geographic variation in tidal wetland vulnerability? How do short term climatic events (storms) influence the...
Vulnerability Assessment of Available Habitat for Wintering Black Ducks within the Refuge System in the Chesapeake Bay
American black duck (Anas rubripes) utilize inland and tidal freshwater and brackish marshes throughout the Chesapeake Bay and are considered to be an indicator species of the ecosystem’s health. Thus, conserving and increasing black duck habitats will subsequently benefit the general health of the bay. The goal of this study was to create a mechanistic model to determine the amount...
Hurricane Sandy Impacts on Coastal Wetland Resilience in the Northeast United States
The Challenge: The high winds and storm surge associated with Hurricane Sandy impacted coastal wetlands from Virginia to Maine. Understanding the ecological and geological impacts of hurricanes on coastal wetlands and their interactive effects with local conditions is important for identifying resilience of these communities to predicted global sea-level rise. Given the projected increase in...
SERAP: Assessment of Shoreline Retreat in Response to Sea Level Rise
The broad range of complex factors influencing coastal systems contribute to large uncertainties in predicting long-term sea level rise impacts. Researchers demonstrated the capabilities of a Bayesian network (BN) to predict long-term shoreline change associated with sea level rise and make quantitative assessments for predicting uncertainty. A BN was used to define relationships between...
Southeast Regional Assessment Project (SERAP): Assessing Global Change Impacts on Natural and Human Systems in the Southeast
The Southeastern United States spans a broad range of physiographic settings and maintains exceptionally high levels of faunal diversity. Unfortunately, many of these ecosystems are increasingly under threat due to rapid human development, and management agencies are increasingly aware of the potential effects that climate change will have on these ecosystems. Natural resource managers and...
Experimental recovery rates of tidal marsh vegetation
We measured the response of plants to disturbance across a gradient in inundation times by transplanting tussocks of Schoenoplectus americanus into mesocosms of different elevation in two marsh organ platforms.
Development of a Multimetric Index for Integrated Assessment of Salt Marsh Ecosystem Condition
This dataset is comprised of eight files related to salt marsh monitoring data or measures of of human disturbance (i.e. human impacts in terms of physical, chemical, and land-use stressors) collected at 33 marsh study units (MSUs) in five National Parks within the NPS Northeast Coastal and Barrier Network (NCBN) along the NE coast of the US.
Coastal marsh degradation into ponds induces irreversible elevation loss relative to sea level
Coastal marshes and their valuable ecosystem services are feared to be lost by sea level rise, yet the mechanisms of marsh degradation into ponds and potential recovery are poorly understood. We quantified and analyzed elevations of marsh surfaces and pond bottoms along a marsh loss gradient (Blackwater River, Maryland, USA). Our analyses show...
Schepers, Lennert; Brennand, Patrick; Kirwan, Matthew L.; Guntenspergen, Glenn R.; Temmerman, Stijn Modelling marsh-forest boundary transgression in response to storms and sea-level rise
The lateral extent and vertical stability of salt marshes experiencing rising sea levels depend on interacting drivers and feedbacks with potential for non‐linear behaviors. A two‐dimensional transect model was developed to examine changes in marsh and upland forest lateral extent and to explore controls on marsh inland transgression. Model...
Carr, Joel A.; Guntenspergen, Glenn R.; Kirwan, Matthew Hurricane Sandy effects on coastal marsh elevation change
High-magnitude storm events such as Hurricane Sandy are powerful agents of geomorphic change in coastal marshes, potentially altering their surface elevation trajectories. But how do a storm’s impacts vary across a large region spanning a variety of wetland settings and storm exposures and intensities. We determined the short-term impacts of...
Yeates, Alice G.; Grace, James; Olker, Jennifer H.; Guntenspergen, Glenn R.; Cahoon, Donald; Adamowicz, Susan C.; Anisfeld, Shimon C.; Barrett, Nels; Benzecry, Alice; Blum, Linda K.; Christian, Rober T; Grzyb, Joseph; Kracauer Hartig, Ellen; Hines Leo, Kelly; Lerberg, Scott; Lynch, James C.; Maher, Nicole; Megonigal, J Patrick; Reay, William G.; Siok, Drexel; Starke, Adam; Turner, Vincent; Warren, Scott Evaluating indicators of marsh vulnerability to sea level rise along a historical marsh loss gradient
Sea level rise (SLR) is threatening coastal marshes, leading to large‐scale marsh loss in several micro‐tidal systems. Early recognition of marsh vulnerability to SLR is critical in these systems to aid managers to take appropriate restoration or mitigation measures. However, it is not clear if current marsh vulnerability indicators correctly...
Schepers, Lennert; Kirwan, Matthew; Guntenspergen, Glenn R.; Temmerman, Stijn Habitat of the endangered salt marsh harvest mouse (Reithrodontomys raviventris) in San Francisco Bay
Understanding habitat associations is vital for conservation of at‐risk marsh‐endemic wildlife species, particularly those under threat from sea level rise. We modeled environmental and habitat associations of the marsh‐endemic, Federally endangered salt marsh harvest mouse (Reithrodontomys raviventris, RERA) and co‐occurrence with eight...
Marcot, Bruce G.; Woo, Isa; Thorne, Karen M.; Freeman, Chase; Guntenspergen, Glenn R. When portfolio theory can help environmental investment planning to reduce climate risk to future environmental outcomes - and when it cannot
Variability among climate change scenarios produces great uncertainty in what is the best allocation of resources among investments to protect environmental goods in the future. Previous research shows Modern Portfolio Theory (MPT) can help optimize environmental investment targeting to reduce outcome risk with minimal loss of expected level of...
Ando , Amy W.; Fraterrigo, Jennifer M.; Guntenspergen, Glenn R.; Howlader, Aparna; Mallory, Mindy L.; Olker, Jennifer H.; Stickley, Samuel Understanding tidal marsh trajectories: Evaluation of multiple indicators of marsh persistence
Robust assessments of ecosystem stability are critical for informing conservation and management decisions. Tidal marsh ecosystems provide vital services, yet are globally threatened by anthropogenic alterations to physical and biological processes. A variety of monitoring and modeling approaches have been undertaken to determine which tidal...
Wasson, Kerstin; Ganju, Neil Kamal; Defne, Zafer; Endris, Charlie; Elsey-Quirk, Tracy; Thorne, Karen M.; Freeman, Chase; Guntenspergen, Glenn R.; Nowacki, Daniel J. ; Raposa, Kenneth B. Thin-layer sediment addition to an existing salt marsh to combat sea-level rise and improve endangered species habitat in California, USA
Current tidal marsh elevations and their accretion rates are important predictors of vulnerability to sea-level rise. When tidal marshes are at risk, adaptation measures, such as sediment addition to increase elevations, can be implemented to prevent degradation and loss. In 2016, wildlife managers prescribed a thin-layer sediment addition of...
Thorne, Karen M.; Freeman, Chase; Rosencranz, Jordan A.; Ganju, Neil Kamal; Guntenspergen, Glenn R.
Hurricane Sandy impacts on coastal wetland resilience
The goal of this research was to evaluate the impacts of Hurricane Sandy on surface elevation trends in estuarine marshes located across the northeast region of the United States from Virginia to Maine using data from an opportunistic (in other words, not strategic) and collaborative network (from here on, an opportunistic network) of surface...
Cahoon, Donald R.; Olker, Jennifer H.; Yeates, Alice G.; Guntenspergen, Glenn R.; Grace, James B.; Adamowicz, Susan C.; Anisfeld, Shimon C.; Baldwin, Andrew H.; Barrett, Nels; Beckett, Leah; Benzecry, Alice; Blum, Linda K.; Burdick, David M.; Crouch, William; Ekberg, Marci Cole; Fernald, Sarah; Grimes, Kristin Wilson; Grzyb, Joseph; Hartig, Ellen Kracauer; Kreeger, Danielle A.; Larson, Marit; Lerberg, Scott; Lynch, James C.; Maher, Nicole; Maxwell-Doyle, Martha; Mitchell, Laura R.; Mora, Jordan; O'Neill, Victoria; Padeletti, Angela; Prosser, Diann J.; Quirk, Tracy; Raposa, Kenneth B.; Reay, William G.; Siok, Drexel; Snow, Christopher; Starke, Adam; Stevenson, J. Court; Staver, Lorie; Turner, Vincent Simulating the effects of climate variability on waterbodies and wetland-dependent birds in the Prairie Pothole Region
Understanding how bird populations respond to changes in waterbody availability in the climatically variable Prairie Pothole Region (PPR) of North America hinges on being able to couple hydrological and climate modeling to represent potential future landscapes. Model experiments run with the Pothole Complex Hydrologic Model using downscaled...
Mcintyre, N.E.; Liu, G.; Gorzo, J.; Wright, C.K.; Guntenspergen, Glenn R.; Schwartz, F. Estimates of tidal-marsh bird densities using Bayesian networks
Conserving tidal-marsh bird communities requires strategies to address continuing pressures from human development to the effects of increasing rates of sea-level rise. Knowing tidal-marsh bird distributions and population sizes are important for developing these strategies. In the Northeast United States, where estimates of sea-level rise are 3...
Wiest, Whitney A.; Correll, Maureen D.; Marcot, Bruce G.; Olsen, Brian J.; Elphick, Chris; Hodgman, Thomas P.; Guntenspergen, Glenn R.; Shriver, W. Gregory U.S. Pacific coastal wetland resilience and vulnerability to sea-level rise
We used a first-of-its-kind comprehensive scenario approach to evaluate both the vertical and horizontal response of tidal wetlands to projected changes in the rate of sea-level rise (SLR) across 14 estuaries along the Pacific coast of the continental United States. Throughout the U.S. Pacific region, we found that tidal wetlands are highly...
Thorne, Karen M.; MacDonald, Glen M.; Guntenspergen, Glenn R.; Ambrose, Richard F.; Buffington, Kevin J.; Dugger, Bruce D.; Freeman, Chase; Janousek, Christopher; Brown, Lauren N.; Rosencranz, Jordan A.; Homquist, James; Smol, John P.; Hargan, Kathryn; Takekawa, John Y.
Managing marsh loss using sediment enhancement to preserve habitat for waterfowl
This article is part of the Spring 2016 issue of the Earth Science Matters Newsletter.