The Sea Level Rise Tipping Point of Delta Survival
Abstract
The estimated rate of global eustatic sea-level rise (RSLR) associated with the formation of thirty-six of the world's coastal deltas was calculated for the last 22,000 years. These deltas are located in a variety of environmental settings in respect to tidal range, isostasy, and climate. After correcting the original uncalibrated radiocarbon age estimates to calibrated years, 90% of the deltas appear to have formed at an average age of 8,109 ± 122 BP and a median age of 7,967 BP. This age corresponds to a period of significant deceleration in the RSLR to between 5 mm yr-1 and 10 mm yr-1, and is in agreement with two regional estimates of vegetation growth limits with respect to RSLR. This RSLR tipping point for delta formation can be used to inform forecasts of delta resiliency under conditions of climate change and concomitant sea level rise. The RSLR is accelerating and will likely be several times higher than the formation tipping point by the end of this century. Hence, the demise of the world's deltaic environments are likely to occur within the same time frame.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMEP14B..02T
- Keywords:
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- 1825 Geomorphology: fluvial;
- HYDROLOGY;
- 1861 Sedimentation;
- HYDROLOGY;
- 4315 Monitoring;
- forecasting;
- prediction;
- NATURAL HAZARDS;
- 4235 Estuarine processes;
- OCEANOGRAPHY: GENERAL