The Sea-Level Change Curve Calculator has been integrated into the Sea Level Tracker (SLT) (accessible here: https://climate.sec.usace.army.mil/slr_app/). We recommend that all United States Army Corps of Engineers (USACE) personnel use the SLT for their analysis going forward to promote consistency across projects. The Calculator will be deprecated at the end of the 2023 calendar year.
Sea-Level Change Curve Calculator (Version ())
This version employs the same computations as previous versions, yielding the same projections along with some additional functionality, the 2014 NOAA rates, and several additional gauges.
ER 1100-2-8162 (pdf, 317 KB) were developed with the assistance of coastal scientists from the NOAA National Ocean Service and the US Geological Survey. Their participation on the USACE team allows rapid infusion of science into engineering guidance. ETL 1100-2-1 (pdf, 9.87 MB) , Procedures to Evaluate Sea Level Change: Impacts, Responses, and Adaptation.
ER 1100-2-8162 (pdf, 317 KB) use the historic rate of sea-level change as the rate for the "USACE Low Curve". ETL 1100-2-1 (pdf, 9.87 MB) , Procedures to Evaluate Sea Level Change: Impacts, Responses, and Adaptation.
The rate for the "USACE Intermediate Curve" is computed from the modified NRC Curve I considering both the most recent IPCC projections and modified NRC projections with the local rate of vertical land movement added.
The rate for the "USACE High Curve" is computed from the modified NRC Curve III considering both the most recent IPCC projections and modified NRC projections with the local rate of vertical land movement added.
The three scenarios proposed by the NRC result in global eustatic sea-level rise values, by the year 2100, of 0.5 meters, 1.0 meters, and 1.5 meters. Adjusting the equation to include the historic GMSL change rate of 1.7 mm/year and the start date of 1992 (which corresponds to the midpoint of the current National Tidal Datum Epoch of 1983-2001), instead of 1986 (the start date used by the NRC), results in updated values for the coefficients (b) being equal to 2.71E-5 for modified NRC Curve I, 7.00E-5 for modified NRC Curve II, and 1.13E-4 for modified NRC Curve III.
The three local relative sea level change scenarios updated from EC 1165-2-212 (pdf, 845 KB) (and and its successor ER 1100-2-8162), Equation 2 are depicted in the Figure to the right of the table. ETL 1100-2-1 (pdf, 9.87 MB) , Procedures to Evaluate Sea Level Change: Impacts, Responses, and Adaptation.
ER 1100-2-8162, Equation 2: E(t) = 0.0017t + bt2
This on-line Sea Level Change Curve Calculator has several added features which are detailed in the User's Manual. You can plot both the USACE and NOAA curves in feet or meters relative to either NAVD88 or LMSL.
This calculator also develops the SLC curves between the user entered dates using equation #3 in ER 1100-2-8162.
See also the USACE Sea Level Tracker to:
About the Program
Climate change has the potential to affect all of the missions of the U.S. Army Corps of Engineers. The Climate Preparedness and Resilience Community of Practice develops and implements practical, nationally consistent, and cost-effective approaches and policies to reduce potential vulnerabilities to water infrastructure resulting from climate change and variability. We work in partnership on this effort with other Federal science and water management agencies, academic experts, the private sector, and other stakeholders.
Planning for Changing Sea Levels
Engineering Technical Letters
SLC User Manual