The floating soccer pitch is not without precedent. There's one in Singapore called The Float at Marina Bay that appears to be a tourist destination as well as a place for sport.
But it's not really a stadium that you could easily transport. Many cruise lines do have some sports on their ships. Shuffleboard, volleyball, and swimming usually pop into mind, but a couple of cruise lines including Norwegian and Royal Carribean have some more elaborate plans for sport on their ships as seen in these renderings:
Still, the question is, will a regulation international football (soccer) pitch fit on a cruise ship or other such vessel? The international football association board sets the dimensions of a standard international field at 330-360 feet long and 210-240 feet wide. As of 2010, Royal Carribean's The Oasis of the Seas, is the largest cruise ship in the world. It is 1,181 feet in length, which is plenty long for several soccer pitches, but the width of the ship is only 154 feet. So, that won't work. How about an aircraft carrier? The flight deck on those seems like the perfect opportunity for introducing sport. Someone else agreed and came up with this Photoshop rendering of a golf course on a flight deck.
If we look at the dimensions of the US aircraft carrier CVN-77 it is 1,040 feet long and 252 feet across. Success! Our World Cup soccer field will fit, although with very little room for bleachers. But they would have room below deck for plenty of concessions and lodging. So, instead of being sore losers, maybe the US can let Qatar borrow a few of our carriers for the event. I'm certain we already have several over there protecting our oil interests anyhow.
