Relative Sea Level Trends before 1992 in the 21st century from Seven GPS-paired Tide Gauge Records along the Coast of the Chesapeake Bay

The Chesapeake Bay (CB) is the largest estuary in the United States and originated from the strike by a bolide 35 million years ago. Global warming since the industrial age has been expediting worldwide sea level rise (SLR). As a result, flood risk and ecosystem change have been elevated. In this study, observations from seven pairs of closely spaced tide gauge (TG) stations and GPS stations around the CB have been analyzed to simulate the SLR process since the 20th century. The CB Coastal Plain wedge owns its outcrops extending from Cretaceous in the Northwest to Holocene in the Southeast. Relative sea-level rise (RSLR) at TG is assumed to be the sum of paired- GPS-detected land subsidence (LS) and absolute sea-level rise (ASLR) in this paper. Before 1992 in the 20th century, three TG stations seated at the Cretaceous zone are Baltimore, Annapolis, and Washington D.C., which have corresponding pairs of RSLR and LS rates of (3.0, 1.9) mm/year, (3.34, 2.24), and (2.68, 1.58), respectively; three TG stations seated at the Tertiary zone are Cambridge, Solomons Island, and Yorktown, which have the corresponding pair of RSLR and LS rates of (3.45, 2.34) mm/year, (3.75, 2.66), and (3.06, 1.96), respectively; and one pair at the Quaternary zone in Kiptopeke indicate the rate of (4.05, 2.95) mm/year. It is estimated that the ASLR before 1992 in the 20th century in the CB area, is about 1.09 to 1.11 mm/year by removing LS from RSLR at above seven TG locations.