Convert from gigagram to tonneau [France]

Unit Definition (gigagram)
An SI unit of mass equal to 10E9 grams, one million kilograms, or 1 kilotonne (1000 metric tons). This unit is used in scientific contexts, such as the measurement of atmospheric emissions. One gigagram equals about 2.2046 million pounds or 1102.3 U.S. (short) tons.

Unit Definition (tonneau [France])
The tonneau is the traditional French ton, equal to 2000 livres or about 979 kilograms (1.079 U.S. ton). The tonneau was also used as a measure of volume equal to 42 cubic pieds (50.84 cubic feet, or about 1440 liters). In the wine trade, the tonneau was a shipment of 100 cases, or 1200 bottles (about 900 liters of wine).