@article {3004,
	title = {Implications of Single-Step Graphitization For Reconstructing Late Holocene Relative Sea-Level Using Radiocarbon-Dated Organic Coastal Sediment},
	journal = {Radiocarbon},
	year = {2022},
	month = {08/2022},
	pages = {1 - 20},
	abstract = {Late Holocene relative sea-level reconstructions are commonly generated using proxies preserved in salt-marsh and mangrove sediment. These depositional environments provide abundant material for radiocarbon dating in the form of identifiable macrofossils (salt marshes) and bulk organic sediment (mangroves). We explore if single-step graphitization of these samples in preparation for radiocarbon dating can increase the number and temporal resolution of relative sea-level reconstructions without a corresponding increase in cost. Dating of salt-marsh macrofossils from the northeastern United States and bulk mangrove sediment from the Federated States of Micronesia indicates that single-step graphitization generates radiocarbon ages that are indistinguishable from replicates prepared using traditional graphitization, but with a modest increase in error (mean/maximum of 6.25/15 additional 14C yr for salt-marsh macrofossils). Low 12C currents measured on bulk mangrove sediment following single-step graphitization likely render them unreliable despite their apparent accuracy. Simulated chronologies for six salt-marsh cores indicate that having twice as many radiocarbon dates (since single-step graphitization costs \~{}50\% of traditional graphitization) results in narrower confidence intervals for sample age estimated by age-depth models when the additional error from the single-step method is less than \~{}50 14C yr (\~{}30 14C yr if the chronology also utilizes historical age markers). Since these thresholds are greater than our empirical estimates of the additional error, we conclude that adopting single-step graphitization for radiocarbon measurements on plant macrofossils is likely to increase precision of age-depth models by more than 20/10\% (without/with historical age markers). This improvement can be implemented without additional cost.},
	keywords = {age-depth model, mangrove, Massachusetts, Micronesia, Salt marsh},
	isbn = {0033-8222, 1945-5755},
	doi = {10.1017/RDC.2022.55},
	url = {https://www.cambridge.org/core/journals/radiocarbon/article/implications-of-singlestep-graphitization-for-reconstructing-late-holocene-relative-sealevel-using-radiocarbondated-organic-coastal-sediment/41F75E6A0679F0E659C96F438452D64C},
	author = {Sefton, Juliet P. and Kemp, Andrew C. and Elder, Kathryn L. and Hansman, Roberta L. and Roberts, Mark L.}
}
@article {2758,
	title = {Salt marsh ecosystem restructuring enhances elevation resilience and carbon storage during accelerating relative sea-level rise},
	journal = {Estuarine, Coastal and Shelf Science},
	volume = {217},
	year = {2019},
	month = {Jan-02-2019},
	pages = {56 - 68},
	abstract = {

Salt marshes respond to sea-level rise through a series of complex and dynamic bio-physical feedbacks. In this study, we found that sea-level rise triggered salt marsh habitat restructuring, with the associated vegetation changes enhancing salt marsh elevation resilience. A continuous record of marsh elevation relative to sea level that includes reconstruction of high-resolution, sub-decadal, marsh elevation over the past century, coupled with a lower-resolution 1500-year record, revealed that relative sea-level rose 1.5 {\textpm} 0.4 m, following local glacial isostatic adjustment (1.2 mm/yr). As sea-level rise has rapidly accelerated, the high marsh zone dropped 11 cm within the tidal frame since 1932, leading to greater inundation and a shift to flood- and salt-tolerant low marsh species. Once the marsh platform fell to the elevation favored by low-marsh Spartina alterniflora, the elevation stabilized relative to sea level. Currently low marsh accretion keeps pace with sea-level rise, while present day high marsh zones that have not transitioned to low marsh have a vertical accretion deficit. Greater biomass productivity, and an expanding subsurface accommodation space favorable for salt marsh organic matter preservation, provide a positive feed-back between sea-level rise and marsh platform elevation. Carbon storage was 46 {\textpm} 28 g C/m2/yr from 550 to 1800 CE, increasing to 129 {\textpm} 50 g C/m2/yr in the last decade. Enhanced carbon storage is controlled by vertical accretion rates, rather than soil carbon density, and is a direct response to anthropogenic eustatic sea-level rise, ultimately providing a negative feedback on climate warming.
},
	keywords = {14-Carbon, accretion, Carbon storage, Elevation, Salt marsh, Sea level index point, sea-level rise},
	issn = {02727714},
	doi = {10.1016/j.ecss.2018.11.003},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0272771418306851},
	author = {Gonneea, Meagan Eagle and Maio, Christopher V. and Kroeger, Kevin D. and Hawkes, Andrea D. and Mora, Jordan and Sullivan, Richard and Madsen, Stephanie and Buzard, Richard M. and Cahill, Niamh and Donnelly, Jeffrey P.}
}
@article {2854,
	title = {Sea Level Rise Explains Changing Carbon Accumulation Rates in a Salt Marsh Over the Past Two Millennia},
	journal = {Journal of Geophysical Research: Biogeosciences},
	volume = {124},
	year = {2019},
	month = {Sep-10-2019},
	pages = {2945 - 2957},
	abstract = {High rates of carbon burial observed in wetland sediments have garnered attention as a potential {\textquotedblleft}natural fix{\textquotedblright} to reduce the concentration of carbon dioxide (CO2) in Earth{\textquoteright}s atmosphere. A carbon accumulation rate (CAR) can be determined through various methods that integrate a carbon stock over different time periods, ranging from decades to millennia. Our goal was to assess how CAR changed over the lifespan of a salt marsh. We applied a geochronology to a series of salt marsh cores using both 14C and 210Pb markers to calculate CARs that were integrated between 35 and 2,460 years before present. CAR was 39 g C{\textperiodcentered}m-2{\textperiodcentered}year-1 when integrated over millennia but was upward of 148 g C{\textperiodcentered}m-2{\textperiodcentered}year-1 for the past century. We present additional evidence to account for this variability by linking it to changes in relative sea level rise (RSLR), where higher rates of RSLR were associated with higher CARs. Thus, the CAR calculated for a wetland should integrate timescales that capture the influence of contemporary RSLR. Therefore, caution should be exercised not to utilize a CAR calculated over inappropriately short or long timescales as a current assessment or forecasting tool for the climate change mitigation potential of a wetland.},
	keywords = {Carbon storage, Geochronology, Salt marsh, sea-level rise},
	issn = {2169-8953},
	doi = {10.1029/2019JG005207},
	url = {https://onlinelibrary.wiley.com/doi/abs/10.1029/2019JG005207},
	author = {McTigue, Nathan and Davis, Jenny and Rodriguez, Antonio B. and McKee, Brent and Atencio, Anna and Currin, Carolyn}
}
@article {Kemp201713,
	title = {Extended late Holocene relative sea-level histories for North Carolina, \{USA\}},
	journal = {Quaternary Science Reviews},
	volume = {160},
	year = {2017},
	pages = {13 - 30},
	abstract = {Abstract We produced \~{}3000-year long relative sea-level (RSL) histories for two sites in North Carolina (USA) using foraminifera preserved in new and existing cores of dated salt-marsh sediment. At Cedar Island, \{RSL\} rose by \~{}2.4~m during the past \~{}3000 years compared to \~{}3.3~m~at Roanoke Island. This spatial difference arises primarily from differential \{GIA\} that caused late Holocene \{RSL\} rise to be 0.1{\textendash}0.2~mm/yr faster at Roanoke Island than at Cedar Island. However, a non-linear difference in \{RSL\} between the two study regions (particularly from \~{}0 \{CE\} to \~{}1250 CE) indicates that additional local- to regional-scale processes drove centennial-scale \{RSL\} change in North Carolina. Therefore, the Cedar Island and Roanoke Island records should be considered as independent of one another. Between-site differences on sub-millennial timescales cannot be adequately explained by non-stationary tides, sediment compaction, or local sediment dynamics. We propose that a period of accelerating \{RSL\} rise from \~{}600 \{CE\} to 1100 \{CE\} that is present at Roanoke Island (and other sites north of Cape Hatteras at least as far as Connecticut), but absent at Cedar Island (and other sites south of Cape Hatteras at least as far as northeastern Florida) is a local-to regional-scale effect of dynamic ocean and/or atmospheric circulation.},
	keywords = {Salt marsh},
	issn = {0277-3791},
	doi = {http://doi.org/10.1016/j.quascirev.2017.01.012},
	url = {http://www.sciencedirect.com/science/article/pii/S0277379116304759},
	author = {Andrew C. Kemp and Jessica J. Kegel and Stephen J. Culver and Donald C. Barber and David J. Mallinson and Eduardo Leorri and Christopher E. Bernhardt and Niamh Cahill and Stanley R. Riggs and Anna L. Woodson and Ryan P. Mulligan and Benjamin P. Horton}
}
@article {2829,
	title = {Relative sea-level trends in New York City during the past 1500 years},
	journal = {The Holocene},
	volume = {27},
	year = {2017},
	month = {Sep-08-2017},
	pages = {1169 - 1186},
	abstract = {New York City (NYC) is threatened by 21st-century relative sea-level (RSL) rise because it will experience a trend that exceeds the global mean and has high concentrations of low-lying infrastructure and socioeconomic activity. To provide a long-term context for anticipated trends, we reconstructed RSL change during the past ~1500 years using a core of salt-marsh sediment from Pelham Bay in The Bronx. Foraminifera and bulk-sediment δ13C values were used as sea-level indicators. The history of sediment accumulation was established by radiocarbon dating and recognition of pollution and land-use trends of known age in down-core elemental, isotopic, and pollen profiles. The reconstruction was generated within a Bayesian hierarchical model to accommodate multiple proxies and to provide a unified statistical framework for quantifying uncertainty. We show that RSL in NYC rose by ~1.70 m since ~575 CE (including ~0.38 m since 1850 CE). The rate of RSL rise increased markedly at 1812{\textendash}1913 CE from ~1.0 to ~2.5 mm/yr, which coincides with other reconstructions along the US Atlantic coast. We investigated the possible influence of tidal-range change in Long Island Sound on our reconstruction using a regional tidal model, and we demonstrate that this effect was likely small. However, future tidal-range change could exacerbate the impacts of RSL rise in communities bordering Long Island Sound. The current rate of RSL rise is the fastest that NYC has experienced for >1500 years, and its ongoing acceleration suggests that projections of 21st-century local RSL rise will be realized.},
	keywords = {Bayesian transfer function, carbon isotope, Foraminifera, Salt marsh, sedimentation, The Bronx},
	issn = {0959-6836},
	doi = {10.1177/0959683616683263},
	url = {http://journals.sagepub.com/doi/10.1177/0959683616683263},
	author = {Kemp, Andrew C and Hill, Troy D and Vane, Christopher H and Cahill, Niamh and Orton, Philip M and Talke, Stefan A and Parnell, Andrew C and Sanborn, Kelsey and Hartig, Ellen K}
}
@article {2489,
	title = {Relative sea-level change in northeastern Florida (USA) during the last \~{}8.0~ka},
	journal = {Quaternary Science Reviews},
	volume = {142},
	year = {2016},
	month = {Jan-06-2016},
	pages = {90 - 101},
	abstract = {An existing database of relative sea-level (RSL) reconstructions from the U.S. Atlantic coast lacked valid sea-level index points from Georgia and Florida. This region lies on the edge of the collapsing forebulge of the former Laurentide Ice Sheet making it an important location for understanding glacio-isostatic adjustment and the history of ice-sheet melt. To address the paucity of data, we reconstruct RSL in northeastern Florida (St. Marys) over the last \~{}8.0 ka from samples of basal salt-marsh sediment that minimize the influence of compaction. The analogy between modern salt-marsh foraminifera and their fossil counterparts preserved in the sedimentary record was used to estimate paleomarsh surface elevation. Sample ages were determined by radiocarbon dating of identifiable and in-situ plant macrofossils. This approach yielded 25 new sea-level index points that constrain a \~{}5.7 m rise in RSL during the last \~{}8.0 ka. The record shows that no highstand in sea level occurred in this region over the period of the reconstruction. We compared the new reconstruction to Earth-ice models ICE 6G-C VM5a and ICE 6G-C VM6. There is good fit in the later part of the Holocene with VM5a and for a brief time in the earlier Holocene with VM6. However, there are discrepancies in model-reconstruction fit in the early to mid Holocene in northeastern Florida and elsewhere along the Atlantic coast at locations with early Holocene RSL reconstructions. The most pronounced feature of the new reconstruction is a slow down in the rate of RSL rise from approximately 5.0 to 3.0 ka. This trend may reflect a significant contribution from local-scale processes such as tidal-range change and/or change in base flow of the St. Marys River in response to paleoclimate changes. However, the spatial expression (local vs. regional) of this slow down is undetermined and corroborative records are needed to establish its geographical extent.},
	keywords = {Foraminifera, Georgia, Holocene, Salt marsh, St. Marys River},
	issn = {02773791},
	doi = {10.1016/j.quascirev.2016.04.016},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S0277379116301275http://api.elsevier.com/content/article/PII:S0277379116301275?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0277379116301275?httpAccept=text/plain},
	author = {Hawkes, Andrea D. and Kemp, Andrew C. and Donnelly, Jeffrey P. and Horton, Benjamin P. and Peltier, W. Richard and Cahill, Niamh and Hill, David F. and Ashe, Erica and Alexander, Clark R.}
}
@article {2494,
	title = {Relative sea-level change in Connecticut (USA) during the last 2200 yrs},
	journal = {Earth and Planetary Science Letters},
	volume = {428},
	year = {2015},
	month = {Jan-10-2015},
	pages = {217 - 229},
	abstract = {We produced a relative sea-level (RSL) reconstruction from Connecticut (USA) spanning the last \~{}2200 yrs that is free from the influence of sediment compaction. The reconstruction used a suite of vertically- and laterally-ordered sediment samples <=2 cm above bedrock that were collected by excavating a trench along an evenly-sloped bedrock surface. Paleomarsh elevation was reconstructed using a regional-scale transfer function trained on the modern distribution of foraminifera on Long Island Sound salt marshes and supported by bulk-sediment δ13C measurements. The history of sediment accumulation was estimated using an age-elevation model constrained by radiocarbon dates and recognition of pollution horizons of known age. The RSL reconstruction was combined with regional tide-gauge measurements spanning the last \~{}150 yrs before being quantitatively analyzed using an error-in-variables integrated Gaussian process model to identify sea-level trends with formal and appropriate treatment of uncertainty and the temporal distribution of data. RSL rise was stable (\~{}1 mm/yr) from \~{}200 BCE to \~{}1000 CE, slowed to a minimum rate of rise (0.41 mm/yr) at \~{}1400 CE, and then accelerated continuously to reach a current rate of 3.2 mm/yr, which is the fastest, century-scale rate of the last 2200 yrs. Change point analysis identified that modern rates of rise in Connecticut began at 1850{\textendash}1886 CE. This timing is synchronous with changes recorded at other sites on the U.S. Atlantic coast and is likely the local expression of a global sea-level change. Earlier sea-level trends show coherence north of Cape Hatteras that are contrasted with southern sites. This pattern may represent centennial-scale variability in the position and/or strength of the Gulf Stream. Comparison of the new record to three existing and reanalyzed RSL reconstructions from the same site developed using sediment cores indicates that compaction is unlikely to significantly distort RSL reconstructions produced from shallow (\~{}2{\textendash}3 m thick) sequences of salt-marsh peat.},
	keywords = {Atlantic Ocean, Foraminifera, Gulf Stream, Late Holocene, Salt marsh},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2015.07.034},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S0012821X15004690http://api.elsevier.com/content/article/PII:S0012821X15004690?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0012821X15004690?httpAccept=text/plain},
	author = {Kemp, Andrew C. and Hawkes, Andrea D. and Donnelly, Jeffrey P. and Vane, Christopher H. and Horton, Benjamin P. and Hill, Troy D. and Anisfeld, Shimon C. and Parnell, Andrew C. and Cahill, Niamh}
}
@article {2497,
	title = {Late Holocene sea- and land-level change on the U.S. southeastern Atlantic coast},
	journal = {Marine Geology},
	volume = {357},
	year = {2014},
	month = {Jan-11-2014},
	pages = {90 - 100},
	abstract = {Late Holocene relative sea-level (RSL) reconstructions can be used to estimate rates of land-level (subsidence or uplift) change and therefore to modify global sea-level projections for regional conditions. These reconstructions also provide the long-term benchmark against which modern trends are compared and an opportunity to understand the response of sea level to past climate variability. To address a spatial absence of late Holocene data in Florida and Georgia, we reconstructed ~ 1.3 m of RSL rise in northeastern Florida (USA) during the past ~ 2600 years using plant remains and foraminifera in a dated core of high salt-marsh sediment. The reconstruction was fused with tide-gauge data from nearby Fernandina Beach, which measured 1.91 {\textpm} 0.26 mm/year of RSL rise since 1900 CE. The average rate of RSL rise prior to 1800 CE was 0.41 {\textpm} 0.08 mm/year. Assuming negligible change in global mean sea level from meltwater input/removal and thermal expansion/contraction, this sea-level history approximates net land-level (subsidence and geoid) change, principally from glacio-isostatic adjustment. Historic rates of rise commenced at 1850{\textendash}1890 CE and it is virtually certain (P = 0.99) that the average rate of 20th century RSL rise in northeastern Florida was faster than during any of the preceding 26 centuries. The linearity of RSL rise in Florida is in contrast to the variability reconstructed at sites further north on the U.S. Atlantic coast and may suggest a role for ocean dynamic effects in explaining these more variable RSL reconstructions. Comparison of the difference between reconstructed rates of late Holocene RSL rise and historic trends measured by tide gauges indicates that 20th century sea-level trends along the U.S. Atlantic coast were not dominated by the characteristic spatial fingerprint of melting of the Greenland Ice Sheet.},
	keywords = {florida, Foraminifera, Glacio-isostatic adjustment Greenland fingerprint, Salt marsh},
	issn = {00253227},
	doi = {10.1016/j.margeo.2014.07.010},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S0025322714002187http://api.elsevier.com/content/article/PII:S0025322714002187?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0025322714002187?httpAccept=text/plain},
	author = {Kemp, Andrew C. and Bernhardt, Christopher E. and Horton, Benjamin P. and Kopp, Robert E. and Vane, Christopher H. and Peltier, W. Richard and Hawkes, Andrea D. and Donnelly, Jeffrey P. and Parnell, Andrew C. and Cahill, Niamh}
}
@article {2506,
	title = {Calibrating a sedimentary record of overwash from Southeastern New England using modeled historic hurricane surges},
	journal = {Marine Geology},
	volume = {275},
	year = {2010},
	month = {Jan-09-2010},
	pages = {127 - 139},
	abstract = {We present a 2000-year record of overwash deposits preserved in a backbarrier salt marsh from southeastern New England. The timing of recent deposits matches well with large hurricane-induced storm surge events documented by local tide gauges in 1991, 1960, 1954, and 1938. Storm surge modeling is used to evaluate the flooding history at the site as well as to assess the pre-instrumental historical record. Storms in 1815, 1727, and 1635 likely caused significant surge that overtopped the barrier, with the timing of coarse-grained overwash deposition correlating well with these events. We infer that twenty-three prehistoric layers mapped across the site were likely also deposited by landfalling hurricanes. Additional records from the area will help to evaluate whether or not temporal trends at the site are a robust representation of hurricane activity for the region. The frequency of overwash at Mattapoisett Marsh, on average 1.5 events per century, is significantly higher than many other overwash-based reconstructions from the western North Atlantic. Further, the Mattapoisett Marsh record does not contain significant multi-centennial gaps in overwash layers. This initial comparison of the data from Mattapoisett marsh with other reconstructions from the western North Atlantic may point toward relatively constant tropical cyclone frequency over the last 2000 years with significant variation in the number of intense tropical cyclones.},
	keywords = {Holocene, hurricane, Paleotempestology, Salt marsh, storm surge, tropical cyclone},
	issn = {00253227},
	doi = {10.1016/j.margeo.2010.05.002},
	url = {http://linkinghub.elsevier.com/retrieve/pii/S0025322710001702http://api.elsevier.com/content/article/PII:S0025322710001702?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0025322710001702?httpAccept=text/plain},
	author = {Boldt, Katherine V. and Lane, Philip and Woodruff, Jonathan D. and Donnelly, Jeffrey P.}
}
@article {1891,
	title = {Sedimentary evidence of hurricane strikes in western Long Island, New York},
	journal = {Geochemistry Geophysics Geosystems},
	volume = {8},
	year = {2007},
	note = {182vrTimes Cited:48
Cited References Count:59
},
	month = {Jun 21},
	abstract = {[1] Evidence of historical landfalling hurricanes and prehistoric storms has been recovered from backbarrier environments in the New York City area. Overwash deposits correlate with landfalls of the most intense documented hurricanes in the area, including the hurricanes of 1893, 1821, 1788, and 1693 A. D. There is little evidence of intense hurricane landfalls in the region for several hundred years prior to the late 17th century A. D. The apparent increase in intense hurricane landfalls around 300 years ago occurs during the latter half of the Little Ice Age, a time of lower tropical sea surface temperatures. Multiple washovers laid down between similar to 2200 and 900 cal yr B. P. suggest an interval of frequent intense hurricane landfalls in the region. Our results provide preliminary evidence that fluctuations in intense hurricane landfall in the northeastern United States were roughly synchronous with hurricane landfall fluctuations observed for the Caribbean and Gulf Coast, suggesting North Atlantic - wide changes in hurricane activity.},
	keywords = {barrier-island, climate, Coastal geology, fire-island, global change : climate variability, hurricane, hydrology : extreme events, hydrology : hydroclimatology, ice-age, New York, new-england, new-jersey, past 5,000 years, Salt marsh, salt-marsh, sea-level rise, sedimentation, tidal marsh, tropical cyclones},
	isbn = {1525-2027},
	doi = {10.1029/2006GC001463},
	author = {Scileppi, E. and Donnelly, J. P.}
}
