A Preindustrial Sea‐Level Rise Hotspot Along the Atlantic Coast of North America

Radiocarbon dates from 176 sites along the Delmarva Peninsula record the timing of deposition and sea-level rise, and non-marine wetland deposition. The dates provide confirmation of the boundaries of the Holocene subepochs (e.g. “early-middle-late” of Walker et al.) in the mid-Atlantic of eastern North America. These data record initial sea-level rise in the early Holocene, followed by a high rate of rise at the transition to the middle Holocene at 8.2 ka, and a leveling off and decrease in the late-Holocene. The dates, coupled to local and regional climate (pollen) records and fluvial activity, allow regional subdivision of the Holocene into six depositional and climate phases. Phase A (>10 ka) is the end of periglacial activity and transition of cold/cool climate to a warmer early Holocene. Phase B (10.2–8.2 ka) records rise of sea level in the region, a transition to Pinus-dominated forest, and decreased non-marine deposition on the uplands. Phase C (8.2–5.6 ka) shows rapid rates of sea-level rise, expansion of estuaries, and a decrease in non-marine deposition with cool and dry climate. Phase D (5.6–4.2 ka) is a time of high rates of sea-level rise, expanding estuaries, and dry and cool climate; the Atlantic shoreline transgressed rapidly and there was little to no deposition on the uplands. Phase E (4.2–1.1 ka) is a time of lowering sea-level rise rates, Atlantic shorelines nearing their present position, and marine shoal deposition; widespread non-marine deposition resumed with a wetter and warmer climate. Phase F (1.1 ka-present) incorporates the Medieval Climate Anomaly and European settlement on the Delmarva Peninsula. Chronology of depositional phases and coastal changes related to sea-level rise is useful for archeological studies of human occupation in relation to climate change in eastern North America, and provides an important dataset for future regional and global sea-level reconstructions.

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Preventing local extinctions of tidal marsh endemic Seaside Sparrows and Saltmarsh Sparrows in eastern North America

The Condor ◽

10.1093/condor/duy024 ◽

2019 ◽

Vol 121 (2) ◽

Cited By ~ 3

Author(s):

Samuel G Roberts ◽

Rebecca A Longenecker ◽

Matthew A Etterson ◽

Chris S Elphick ◽

Brian J Olsen ◽

...

Keyword(s):

New Jersey ◽

North America ◽

Sea Level Rise ◽

Sea Level ◽

Salt Marshes ◽

Local Population ◽

Population Persistence ◽

Vital Rates ◽

Saltmarsh Sparrow ◽

Management Actions

Abstract Globally limited to 45,000 km2, salt marshes and their endemic species are threatened by numerous anthropogenic influences, including sea-level rise and predator pressure on survival and nesting success. Along the Atlantic coast of North America, Seaside (Ammospiza maritima) and Saltmarsh (A. caudacuta) sparrows are endemic to salt marshes, with Saltmarsh Sparrows declining by 9% annually. Because vital rates and factors affecting population persistence vary for both species, local estimates are necessary to best predict population persistence in response to management actions. We used a metapopulation model to estimate the population viability of the breeding Seaside and Saltmarsh sparrow populations in coastal New Jersey over a 42-yr period. We incorporated empirical data on the vital rates and abundances of these populations and simulated the effect of low (0.35 m) and high (0.75 m) levels of sea-level rise. We found that the Seaside Sparrow population persisted under both sea-level rise scenarios; however, the Saltmarsh Sparrow population reached a quasi-extinction threshold within 20 yr. Using the same framework, we modeled potential management scenarios that could increase the persistence probability of Saltmarsh Sparrows and found that fecundity and juvenile survival rates will require at least a 15% concurrent increase for the local population to persist beyond 2050. Future field research should evaluate the feasibility and effectiveness of management actions, such as predator control, for increasing Saltmarsh Sparrow vital rates in order to maintain the species in coastal New Jersey.

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Application of STORMTOOLS Coastal Environmental Risk Index (CERI) to Inform State and Local Planning and Decision Making along the Southern RI Shoreline

Journal of Marine Science and Engineering ◽

10.3390/jmse8040295 ◽

2020 ◽

Vol 8 (4) ◽

pp. 295

Author(s):

Malcolm L. Spaulding ◽

Annette Grilli ◽

Chris Damon ◽

Teresa Crean ◽

Grover Fugate

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Rhode Island ◽

Environmental Risk ◽

Structural Damage ◽

Risk Index ◽

Atlantic Coast ◽

Wave Model ◽

Flood Plain ◽

State And Local

STORMTOOLS coastal environmental risk index (CERI) was applied to communities located along the southern coast of Rhode Island (RI) to determine the risk to structures located in the flood plain. CERI uses estimates of the base flood elevation (BFE), explicitly including the effects of sea level rise (SLR); details on the structure types, from the E911 emergency data base/parcel data, and associated first floor elevation (FFE); and damage curves from the US Army Corp of Engineers North Atlantic Coast Comprehensive Study (NACCS) to determine the damages to structures for the study area. Surge levels and associated offshore waves used to determine BFEs were obtained from the NACCS hydrodynamic and wave model predictions. The impacts of sea level rise and coastal erosion on flooding were modeled using XBeach and STWAVE and validated by observations at selected locations along the coastline. CERI estimated the structural damage to each structure in the coastal flood plain for 100 yr flooding with SLR ranging from 0 to 10 ft. The number of structures at risk was estimated to increase approximate linearly from 3700 for no SLR to about 8000 for 10 ft SLR, with about equal percentages for each of the four coastal communities (Narragansett, South Kingstown, Charlestown, and Westerly, Rhode Island (RI)). The majority of the structures in the flood plain are single/story residences without (41%) and with (46%) basements (total 87%; structures with basements are the most vulnerable). Less vulnerable are structures elevated on piles with 8.8% of the total. The remaining are commercial structures principally located either in the Port of Galilee and or Watch Hill. The analysis showed that about 20% of the structures in the 100 yr flood plain are estimated to be damaged at 50% or greater. This increases to 55% of structures as SLR rises to 5 ft. At higher SLR values the percent damaged at 50% or greater slowly declines to 45% at 10 ft SLR. This behavior is a result of the number of homes below MSL increasing dramatically as SLR values moves higher than 5 ft and thus being removed from the structures damaged pool. Generalized CERI risk maps have developed to allow the managers to determine the broad risk of siting structures at any location in their communities. CERI has recently become available as a mobile phone App, facilitating the ability of state and local decision makers and the public to determine the risk of locating a selected building type at any location in their communities.

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Spatio-temporal decomposition of geophysical signals in North America

10.5194/egusphere-egu2020-16232 ◽

2020 ◽

Author(s):

Aoibheann Brady ◽

Jonathan Rougier ◽

Bramha Dutt Vishwakarma ◽

Yann Ziegler ◽

Richard Westaway ◽

...

Keyword(s):

North America ◽

Sea Level Rise ◽

Sea Level ◽

Global Scale ◽

Bayesian Hierarchical ◽

Isostatic Adjustment ◽

Modelling Framework ◽

Vertical Land Motion ◽

Early Results ◽

Spatio Temporal

<p>Sea level rise is one of the most significant consequences of projected future changes in climate. One factor which influences sea level rise is vertical land motion (VLM) due to glacial isostatic adjustment (GIA), which changes the elevation of the ocean floor. Typically, GIA forward models are used for this purpose, but these are known to vary with the assumptions made about ice loading history and Earth structure. In this study, we implement a Bayesian hierarchical modelling framework to explore a data-driven VLM solution for North America, with the aim of separating out the overall signal into its GIA and hydrology (mass change) components. A Bayesian spatio-temporal model is implemented in INLA using satellite (GRACE) and in-situ (GPS) data as observations.&#160;Under the assumption that GIA varies in space but is constant in time, and that hydrology is both spatially- and temporally-variable, it is possible to separate the contributions of each component with an associated uncertainty level. Early results will be presented. Extensions to the BHM framework to investigate sea level rise at the global scale, such as the inclusion of additional processes and incorporation of increased volumes of data, will be discussed.</p>

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Global sea level rise and glacial isostatic adjustment: An analysis of data from the East Coast of North America

Geophysical Research Letters ◽

10.1029/96gl00848 ◽

1996 ◽

Vol 23 (7) ◽

pp. 717-720 ◽

Cited By ~ 62

Author(s):

W. R. Peltier

Keyword(s):

North America ◽

Sea Level Rise ◽

Sea Level ◽

East Coast ◽

Glacial Isostatic Adjustment ◽

Isostatic Adjustment ◽

Global Sea Level

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An extreme event of sea-level rise along the Northeast coast of North America in 2009–2010

Nature Communications ◽

10.1038/ncomms7346 ◽

2015 ◽

Vol 6 (1) ◽

Cited By ~ 103

Author(s):

Paul B. Goddard ◽

Jianjun Yin ◽

Stephen M. Griffies ◽

Shaoqing Zhang

Keyword(s):

North America ◽

Sea Level Rise ◽

Sea Level ◽

Extreme Event ◽

Northeast Coast

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