Hydrology is destiny
I’ve written before about topography, but without expanding on the fact that all topography is shaped by plate tectonics and water. Every ridge and valley was carved by rain. Settlement patterns, cultural links, trade have all been shaped by hydrology. Sorkin already mentioned “the rate at which the seas are rising” (#16), and this prompt may simply be reiterating the impact of rising seas.
On the micro scale, ‘hydrology is destiny’ has a different connotation. Moisture in soils freeze and thaw every year, cracking and chipping away at concrete. Moisture attacks steel and rots wood. No engineer ever designs a structure to be ‘permanent’. Everything is slowly degrading – eaten away, mostly by water. Everything is designed to fail in a manageable way.