General characteristics of sea-level changes along the North Atlantic coast in the past 2000 years

The North Atlantic coast is one of the most vulnerable regions to sea-level rise in the world. The history and characteristics of the past sea-level changes in the region is of great scientific significance for understanding the course of modern sea-level changes and for predicting the trend of future sea-level changes, and also helps minimize the uncertainty of prediction results. Therefore, it is necessary to systematically analyze and integrate the published sea-level data as well as the tidal observation records along the North Atlantic coast. Using the available 1 350 tidal observation records and 1 604 calibrated data, the history of sea-level changes along the North Atlantic coast in the past 2000 years was established, and the main processes and characteristics, regional differences, and existing issues of sea-level changes along the North Atlantic coast in the past 2000 years were analyzed. Results show that: ① the sea-level changes in the North Atlantic coast in the past 2000 years are remarked by significant spatial and temporal differences, as well as the regional differences in amplitude and frequency. ② The sea-level along the North Atlantic coast shows a fluctuating upward trend in the past 2000 years, but the elevations of sea-level rising in different regions are quite different in different coastal regions. The sea-level rise in the eastern coast of North America is more than 2.5 m. The sea-level rise in Greenland-Iceland, Europe, and the southern and southeastern parts of the United States is about 1.9 m. The sea level rise in the North Sea and the Mediterranean is about 1 m. ③ Since 1900 AD, the rate of sea-level rise along the east and west coast of the North Atlantic has generally accelerated, showing a significant difference in latitude, namely, from the Mediterranean to the European coast to Greenland-Iceland on the east coast of the North Atlantic, the sea-level rise rate gradually increases with the increase of latitude. Similarly, from the south and southeast of the United States on the west coast of the North Atlantic to the east of the United States and then to the east of Canada, with the increase of latitude, the sea-level rise rate also increases in turn. ④ The sea-level change and its temporal and spatial differences in the North Atlantic coast during the past 2000 years are likely the combined effects of various factors. The alternation of cold and warm climate, glacial isostatic adjustment, atmospheric-ocean dynamics, regional tectonic movement, coastal terrain changes, sediment compaction, and tidal range changes may be the main reasons.