No they don't. They emit about 0.25 gigatonnes annually. That's less than one percent as

在长期观测下我们发现大气中碳十三的浓度正在减少。

Today, that figure is already down to less than 350 gigatonnes.

今天，这一数字已经降到了3500亿吨。

I'll take a guess at b) 500 gigatonnes.

我猜是b) 5000亿吨。

Yes, you asked me how many gigatonnes of Greenland's ice sheet are now melting every year.

是的，你问我格陵兰岛现在每年融化多少冰原。

So my quiz question is this: how many gigatonnes of ice are now melting into the ocean every year?

每年有多少海冰融入海洋？

However, last year coal-fired electricity emitted more than ten gigatonnes of carbon dioxide for the first time, 30% of the world's total.

然而，去年燃煤发电首次排放了超过100亿吨的二氧化碳，占世界总量的30%。

So overall, they found discrepency of three gigatonnes which in lams and terms as 10% of the global emissions in 2013.

总之，他们发现了中国30亿吨的差额，这相当于2013年全球排放量的10%。

If nothing is done, pollution from two- and three-wheeled vehicles in Africa will hit 1.7 gigatonnes of emissions every year, according to our estimates.

如果什么都不做，根据我们的估计，两、三轮车辆的污染排放量将会达到每年十七亿吨。

Is it a) 450 gigatonnes, b) 500 gigatonnes, or c) 550 gigatonnes?

是 A. 450 千兆吨，B.500 千兆吨，还是 C. 550 千兆吨？