Graphic of Observed sea-level trends (NOAA), Coastal Vulnerability Index (USGS), USACE Projects, and Port  Tonnage on map of Population Density (Census)

Observed sea-level trends (NOAA), Coastal Vulnerability Index (USGS), USACE Projects, and Port Tonnage on map of Population Density (Census).

We know sea levels are changing, both globally and locally. Sea-level change will be the foundation

This map represents collaborative efforts with USGS and NOAA around understanding sea-level change.

Observed sea-level trends, both rising and falling (as shown by arrows), for CONUS are superimposed on a map showing the population density of the US (darker colors with greater population densities). USACE projects are the black dots, and ports are purple, with the relative size of the purple dots corresponding to annual tonnage. It’s clear that inland areas – the source of raw and manufactured products shipped through the ports – are tied to coastal areas by a complex network, including the inland navigation system, road and rail transport, and supply chains. Also note the large population densities close to the coast – with the implication that economic damages associated with increased sea-level are large. So coastal changes will impact inland areas as well.

The USGS Coastal Vulnerability Index, representing potential for erosion of undeveloped coastlines under changing sea level, is shown as a multicolored ribbon along the edge of the coastline. This index is a composite made from six variables and parameters. Here, green represents low vulnerability, and red represents very high vulnerability. USGS is working with us on a more sophisticated analysis that will help us better define risks to our projects at a finer resolution.

Contributors: Gregg Bertrand (graphic design), Rob Thieler (USGS), Steve Gill (NOAA), Heidi Moritz (NWP Technical Team Lead), Henri Langlois (IWR, Planning Lead), Kate White (IWR, Program Manager)