Convert Gigatons to Megatons

Convert Gigatons (Gt) to Megatons (Mt) instantly and accurately.

Gigatons (Gt)
Megatons (Mt)

Conversion Formula

Mt = Gt × 1000

About Gigatons

A gigaton (Gt) equals one billion metric tonnes (10¹² kg). It is the standard unit for planetary-scale mass measurements and global environmental budgets. Annual human CO₂ emissions are approximately 37 Gt CO₂; Earth's atmosphere contains roughly 5,480 Gt of air; Antarctic ice sheet mass is around 26,500,000 Gt of ice. Climate scientists report ice sheet mass balance changes in gigatons per year - the Greenland ice sheet loses approximately 280 Gt of ice annually due to climate change.

About Megatons

A megaton (Mt) equals one million metric tonnes (10⁹ kg). Nuclear weapon yields are measured in megatons of TNT equivalent: the largest weapon ever detonated, the Soviet Tsar Bomba tested in 1961, had a yield of approximately 50 Mt TNT and produced a fireball 8 km in diameter. Annual global CO₂ emissions are reported in gigatons (Gt), but regional emissions data and specific industrial sectors are quoted in megatons. The Chicxulub asteroid impact that caused the Cretaceous-Paleogene mass extinction released energy equivalent to roughly 100 million Mt of TNT.

Quick Reference Table

Gigatons (Gt)Megatons (Mt)
1 Gt1000 Mt
2 Gt2000 Mt
5 Gt5000 Mt
10 Gt10000 Mt
25 Gt25000 Mt
50 Gt50000 Mt
100 Gt100000 Mt

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