Past and future sea-level rise along the coast of North Carolina, USA

Abstract

We evaluate relative sea level (RSL) trajectories for North Carolina, USA, in the context of tide-gauge measurements and geological sea-level reconstructions spanning the last $\mathord{\sim}$11,000 years. RSL rise was fastest ($\mathord{\sim}$7 mm/yr) during the early Holocene and slowed over time with the end of the deglaciation. During the pre-Industrial Common Era (i.e., 0--1800 CE), RSL rise ($\mathord{\sim}$0.7 to 1.1 mm/yr) was driven primarily by glacio-isostatic adjustment, though dampened by tectonic uplift along the Cape Fear Arch. Ocean/atmosphere dynamics caused centennial variability of up to $\mathord{\sim}$0.6 mm/yr around the long-term rate. It is extremely likely (probability $P = 0.95$) that 20th century RSL rise at Sand Point, NC, (2.8 $\pm$ 0.5 mm/yr) was faster than during any other century in at least 2,900 years. Projections based on a fusion of process models, statistical models, expert elicitation, and expert assessment indicate that RSL at Wilmington, NC, is very likely ($P = 0.90$) to rise by 42--132 cm between 2000 and 2100 under the high-emissions RCP 8.5 pathway. Under all emission pathways, 21st century RSL rise is very likely ($P > 0.90$) to be faster than during the 20th century. Due to RSL rise, under RCP 8.5, the current `1-in-100 year' flood is expected at Wilmington in $\mathord{\sim}$30 of the 50 years between 2050-2100.Comment: 13 main text pages, 4 figures, 4 supplemental pages. Published in Climatic Chang

Variations in the difference between mean sea level measured either side of Cape Hatteras and their relation to the North Atlantic Oscillation

“…Greenland (Tamisiea and Mitrovica 2011;Kopp et al 2015), and to the many glaciological and hydrological processes that result in 'eustatic' sea level changes. A geophysical fingerprint due to melting of the Greenland ice sheet equivalent to a global-average sea level rise of 1 mm/year would produce a rate of rise measured in Florida that is several tenths of mm/year larger than that in Nova Scotia (Tamisiea and Mitrovica 2011).…”

Holocene Relative Sea-Level Changes from Near-, Intermediate-, and Far-Field Locations

“…We expand on recent reviews showing Holocene RSL variability [13,[44][45][46][47] by applying a non-parametric statistical technique (empirical hierarchical modeling with Gaussian process priors) that appropriately accounts for the vertical and chronological uncertainties of the RSL data to provide a probabilistic assessment of past RSL changes and rates of past RSL change [48][49][50]. This method has not been previously adopted to describe spatial variability in RSL change on a global scale and represents a [54,56], Northwest Georgia Strait, Canada [49], Southern Maine, USA [71], New Jersey, USA [43], Louisiana, USA [74], California, USA [49], St. Croix [99], Suriname and Guyana [100 ], Rio Grande do Norte State, Brazil [102], and South Shetland Islands, Antarctica [112,114].…”

Analyzing the Effect of Ocean Internal Variability on Depth-Integrated Steric Sea-Level Rise Trends Using a Low-Resolution CESM Ensemble

“…However, there are potentially large uncertainties due to lack of ocean temperature observations, particularly for the deep ocean (below 2000 m) [1, [3][4][5], and in the Southern Hemisphere, where observational coverage is sparse [6][7][8][9][10][11][12][13]. Uncertainties in both observed and modeled sea-level change can influence interpretations about sea-level rise risks [14][15][16], such as flooding, increased storm surge and coastal erosion [1, 16,17]. In addition, characterising the relative contributions of different integrated ocean depths to steric sea-level rise can provide important insights about the vertical structure of ocean…”