Abstract: A multi-purpose cargo hold, carrier vessel, and shipping methods for circulating conditioned air through multiple levels and types of cargo situated therein. Disclosed are apparatus and methods for shipping and conditioning air surrounding cargo on a carrier vessel comprising the steps of loading cargo onto a loading means; forming a plurality of air gaps throughout the cargo in the cargo hold; placing supply and return air plenums in fluid communication with one another; and delivering and circulating conditioned air to cargo via an air conditioning means.