A Water World conjures up an image of an ocean that stretches on forever. In Traveller, a planet with a Hydrographic Percentage of A, or 100% is termed a “Water World”. Interestingly, a Hydrographic Percentage of A actually covers a range of values between 90% and 100% so our empty ocean may actually have small islands scattered across it – as long as they cover less than 10% of the planet’s surface.
What of the inhabitants of such a Water World? If we assume that they are air-breathers, possible inhabitants might live on ships or on rafts or in floating cites, endlessly following the ocean currents. Equally, the inhabitants could live in undersea domed cities, using submersibles or crawlers to harvest sea life or extract resources from the sea bed and deep sea subduction zones. Perhaps, the inhabitants are either like seabirds or have seabird-like gliding technology and circumnavigate the planet, going from lonely outcrop to lonely outcrop in an endless cycle, hunting and fishing as they soar and swoop across the long, slow ocean swells.
Perhaps the inhabitants are amphibious or aquatic, living partially or totally beneath the waves, either able to breath both above and below the water, or living fully beneath the sea. Would a semi-aquatic or fully aquatic species be able to develop technology? Or would they be a race of philosophers, working out deep and complex equations and theories and debating them back and forth in mile-spanning booms and clicks and cheeps? Would they speculate on the nature of the stars and life on other planets as they float beneath the summer skies or would their observational sciences be swiftly overtaken by speculation and mythology if they lack the means to conduct experiments? Could an amphibious race develop smelting and metal working on the little outcrops of rock and tiny islands dotted across the world ocean?
Kevin Costner famously made a movie called “Water World” which was a bit of a career wrecker – Mad Max on jet skies - and proved that throwing a squillion dollars at a bad story does not make for a good movie, even if it contains good ideas. J. G. Ballard’s novel, “The Drowned World”, looked at life in post-Global Warming London and is an example of how humans might adapt to a major change in climate and sea level, while Jules Verne’s famous novel, “20,000 Leagues under the Sea”, examined life aboard a submersible craft.
Water Worlds can provide a very different environment in which to adventure – both like and unlike outer space with all its associated issues for air breathers. And there are many ways to approach the development of such planets, and the cultures and species that might evolve on or colonise such environments, from the fairly familiar to the completely exotic.