A sustained Moon-base or Mars-settlement program is plausibly a multi-decade to multi-generational endeavor: NASA’s Artemis planning explicitly frames the next decade as laying foundations for a “sustained” lunar presence, and NASA’s “Moon to Mars” framing envisions human Mars missions beginning in the 2030s with follow-on activity thereafter. (NASA)

Over those same horizons, credible assessments project meaningful sea-level rise even under lower-emissions pathways, with larger rises possible under higher-emissions or high-end ice-sheet outcomes. The IPCC AR6 assessment (as summarized in its sea-level datasets/tools) gives likely global mean sea-level rise by 2100 (relative to 1995–2014) of roughly 0.28–0.55 m under very low emissions (SSP1-1.9) and 0.63–1.01 m under very high emissions (SSP5-8.5), with additional rise beyond 2100 depending on emissions and ice-sheet behavior. (IPCC Browser) NOAA’s U.S. sea-level scenario work also highlights a wide planning envelope, with global mean sea level scenarios by 2100 spanning roughly 0.3 m up to 2.5 m to bound uncertainty and low-probability/high-impact outcomes. (NOAA Ocean Service)

For conventional rocket-based launch, this creates an accumulating infrastructure-risk problem because major spaceports and their logistics ecosystems are typically coastal and low-lying: adaptation could require dikes, causeways, elevated pads, hardened utilities, raised access roads/rail, storm-surge defenses, and repeated retrofits to keep cryogenic storage, power distribution, clean rooms, and processing facilities operational as flooding frequency increases. If protection becomes uneconomic, relocation pressure rises—potentially at the same time that surrounding communities and industries are also competing to relocate, rebuild, or harden infrastructure, which can spike costs and disrupt labor, housing, transport, and permitting.

In a supply-chain context, the failure mode that matters is not just long-run capex, but schedule risk: if sea-level rise (or storm-surge exposure on top of higher mean sea level) accelerates faster than anticipated, a coastal launch base could face intermittent shutdowns or major rebuild windows that directly interrupt the cadence needed to deliver critical spares, consumables, and fresh crew to a lunar base or Mars program.

VPSL’s architecture is inherently resilient to sea-level rise. By placing its horizontal acceleration section offshore and submerged and routing its ramp through a tunnel to high elevation, VPSL avoids dependence on low-lying coastal infrastructure. This replaces the challenge of indefinitely defending a massive coastal spaceport with operating a smaller, naturally sea-level-insensitive facility—better suited to sustaining long-term off-world supply lines.