Given such dramatic traffic increases, one could consider simply building a brand-new airport in one or both countries, but it is not merely tarmac and hangars that are required, but a local economy to employ, house, and feed the many thousands of people required to staff this operation. To enable airport construction, the adjacent seaport would need to be expanded to bring in all the construction materials, fuel, sulfur, and other supplies. There is no large economic engine such as Anchorage or Stockholm in this region on which to piggyback, and there is no reasonable geographic alternative to Patagonia. One could perhaps reconceive these southern bases as isolated military installations, but that wouldn’t much change the infrastructure build-out required. Neither Chile nor Argentina would have any incentive to commence such a project until some external funding source stood ready to foot the bill. Nonetheless, given the low ebb at which these projects would start, it may be that the ground infrastructure build-out at the tip of Patagonia would define the critical path for global readiness to arrest the emergence of tipping points at the poles.
A review of public information about newly finished or ongoing airport construction projects around the world provides context regarding the granular cost and span information received from ANC and ARN. A list of substantially all new large commercial airports opened in the last 30 years for which publicly reported cost data is available suggests an average initial development cost of 5.8 billion in 2023 dollars. However, as this includes both very large and mid-sized airports, it is a very crude metric. Dividing these costs by the number of aircraft movements in a recent year yields a cost-per-100,000-movements of $2.9 billion. Alternatively, simply dividing development cost by the number of runways (another crude metric of airport capacity) yields a cost per runway of $2.6 billion. As we envision airports with 2 runways, this would suggest a cost of $5.2 billion for new SAI airports. This array of figures confirms that ANC’s estimate of $3 billion for a brand new airport is on the low end of a very reasonable range. We will therefore assume that a new airport of the size envisioned here might cost $3 – 5 billion. They also confirm that ANC’s estimate $2.3 billion to double the capacity of an airport currently handling roughly 100,000 aircraft movements per year is also reasonable, leading to a planning figure for such an expansion of $2 – 3 billion.