A geological perspective on sea-level rise and impacts along the U.S. mid-Atlantic coast.

TitleA geological perspective on sea-level rise and impacts along the U.S. mid-Atlantic coast.
Publication TypeJournal Article
Year of Publication2013
AuthorsMiller KG, Kopp RE, Horton B, Browning JV, Kemp AC
JournalEarth's Future
Date Published12/2013

We evaluate paleo-, historical, and future sea-level rise along the U.S. mid-Atlantic coast. The rate of relative sea-level rise in New Jersey decreased from 3.5 ± 1.0 mm/yr at 7.5–6.5 ka, to 2.2 ± 0.8 mm/yr at 5.5–4.5 ka to a minimum of 0.9 ± 0.4 mm/yr at 3.3–2.3 ka. Relative sea level rose at a rate of 1.6 ± 0.1 mm/yr from 2.2 to 1.2 ka (750 Common Era [CE]) and 1.4 ± 0.1 mm/yr from 800 to 1800 CE. Geological and tide-gauge data show that sea-level rise was more rapid throughout the region since the Industrial Revolution (19th century = 2.7 ± 0.4 mm/yr; 20th century = 3.8 ± 0.2 mm/yr). There is a 95% probability that the 20th century rate of sea-level rise was faster than it was in any century in the last 4.3 kyr. These records reflect global rise (∼1.7 ± 0.2 mm/yr since 1880 CE) and subsidence from glacio-isostatic adjustment (∼1.3 ± 0.4 mm/yr) at bedrock locations (e.g., New York City). At coastal plain locations, the rate of rise is 0.3–1.3 mm/yr higher due to groundwater withdrawal and compaction. We construct 21st century relative sea-level rise scenarios including global, regional, and local processes. We project a 22 cm rise at bedrock locations by 2030 (central scenario; low- and high-end scenarios range of 16–38 cm), 40 cm by 2050 (range 28–65 cm), and 96 cm by 2100 (range 66–168 cm), with coastal plain locations having higher rises (3, 5–6, and 10–12 cm higher, respectively). By 2050 CE in the central scenario, a storm with a 10 year recurrence interval will exceed all historic storms at Atlantic City.