Cows: Bum Or Burp?
The atmospheric scientists tell us that we humans have affected our planet's atmosphere in two major ways.
We have punched a hole in the ozone layer; and we have, quite separately, set off global warming by dumping so-called greenhouse gases into the atmosphere.
Most of us know that the most villainous of these gases is carbon dioxide. Many of us probably know that methane from cattle and sheep is another significant greenhouse gas.
But practically all of us wrongly believe that this methane gas comes from the back end of the animals. And very few of us know that methane is 22-or-so times nastier than carbon dioxide.
