Convert from carat [metric] to gigatonne

Unit Definition (carat [metric])
A metric carat defined in 1907 to be exactly 200 milligrams.

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.