FINDING 3.4: The U.S. military is well aware of the risks to its coastal facilities and infrastructure from sea-level rise. Recent observations of sea-level rise have exceeded projections made only a decade earlier, and the increasing realization of the potential of changes in ice dynamics leads to the further realization that there perhaps continues to be underestimation of the sea-level rise that would be associated with likely future climate change. The risk of harm to military and civilian coastal facilities from sea-level rise is not linear with the rate of rise. There will be thresholds at which existing natural and built coastal barriers are exceeded. An important dimension of this risk is that of storm surge, especially if warmer future conditions give rise to an increased intensity of storms.

RECOMMENDATION 3.4: For risk management purposes, U.S. naval leaders would be prudent to err on the side of overestimation of future sea-level rise when renovating existing or planning new coastal facilities. The Navy and other branches of U.S. services that have historic commitments to HA/DR efforts for the United States and beyond need to consider as highly probable the need to enhance these capabilities to be prepared for increased damage from coastal storms.