Convert from microgram to gigatonne

Unit Definition (microgram)
The microgram is a metric unit of mass equal to 0.001 milligram (mg) or one millionth of a gram. Ingredients of drugs and vitamins are often stated in micrograms.

Unit Definition (gigatonne)
The gigatonne is a metric unit of mass or weight equal to one billion metric tons (tonnes) or about 2.2046 trillion pounds. This very large unit is used, for example, in discussing the amounts of carbon added to the atmosphere by human activities.