Transport varies for the cost and the purpose.

 This is a table show the energy used to move freight

Carbonfund.org’s shipping calculator utilizes three user generated inputs to determine a unit called a ‘ton-mile’ (e.g. a ton of freight traveling 1 mile, or a half ton of freight traveling two miles, or 1/1000th of a ton traveling 1,000 miles… you get the point):

Total number of shipments
Avg Weight of Shipment (lbs)
Avg Shipping Distance (mi)
Shipping Emissions Factors:

Air cargo – 1.527 kg CO2 per Ton-Mile
Truck - 0.297 kg CO2 per Ton-Mile
Train - 0.0252 kg CO2 per Ton-Mile
Sea freight - 0.048 kg CO2 per Ton-Mile
(Source: EPA Climate Leaders)

Source: http://www.carbonfund.org/how-we-calculate