A unit of explosive force equal to one billion (10⁹) tons of trinitrotoluene (TNT)
- ‘You know we're going to probably put somewhere around 3,000 maybe 4,000 gigatons of carbon into the atmosphere over a period of let's say 300 years.’
- ‘The protocol will only come into force after it is signed by at least 55 countries whose total greenhouse gas emissions accounted for at least 55 percent of global emissions in 1990, which was 13.7 gigatons.’
- ‘Now, we are spewing out more than 7 gigatons of carbon a year and large amounts of other greenhouse gases such as methane.’
- ‘Nature produces silica on a scale of gigatons - thousands of millions of tons - thousands-fold more than man can produce, said Morse.’
- ‘Britain's BBC reports that an annual emission of 29 gigatons of CO2 would mean 'the mass death of forests, with the trees releasing the CO2 they had stored up, adding to global warming instead of restraining it.'’
We take a look at several popular, though confusing, punctuation marks.