@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 {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}
}
