Far secondary to the many physical (and geophysical) problems with your scenario, but it sounds like you have to EVOLVE, within just a few thousand years, the thousands and thousands and thousands of species, often with highly unusual or specialized adaptations, uniquely suited to living in alpine, arctic, abyssal and other extreme environments which didn't exist before the flood.
But then I suppose this is only an intensification of a more general problem with the global flood / Noah's Ark scenario: that it requires rates of EVOLUTION far faster than evolutionists would consider remotely plausible. IOW only a few thousands, at most tens of thousands, of "created kinds" can be fit into the ark (each with only the biological diversity that can be held in a population of 2, or in some cases 14, individuals); but only a few thousands of years later you have millions, and possibly tens of millions, of distinct species inhabiting the earth.
You make it sound like a miracle.
"The animals on the ark would repopulate the world by migrating away from the ark landing site. The mountainous area around the ark would be ideal to encourage successful repopulation, as a mountainous area contains varying ecological zones and would tend to fragment the growing population into sub-populations (different "herds") giving the animal type multiple chances to avoid extinction. Inbreeding within these sub-populations would also cause differing traits to become dominant within each sub-population, leading to the formation of what we now call different "species" ("rapid speciation"). It is important to remember that speciation (the formation of a new species) is NOT evolution, as no new complexity is being introduced, only the rearranging of existing genetic information. We must also remember that it was God who made the final selection of the animals for the ark. This was necessary as only God could know the genetic makeup of the individual animals, and it was important to choose animals having the widest range of genetic potential. But even if this were not the case, it is true that most of the potential variation of any type of animals will be found in every male/female pair. There are modern day examples of a pair or small number of individuals successfully starting a repopulation effort that eventually leads to a diversified population exhibiting much variation (such as the rock pigeon introduced into the USA from England)."
http://emporium.turnpike.net/C/cs/ark/sld020.htm
Why not? Are you saying that is impossible?