There are actually several greenhouse gases, but carbon dioxide is the one that gets all the publicity.
A more potent gas, that warms the atmosphere at up to 33 times the effect of CO2, is methane.
This is one of the reasons that being vegetarian is better for the environment – one of the greatest contributors to global warming is the livestock that we farm to eat.
Scientists from The University of Copenhagen have been measuring atmospheric conditions for the last 2,100 years by looking at drilled sections of the Greenland ice sheet. Ice sheets are accurate recorders of atmospheric gas concentrations going back over millenia. Snow falls through the atmosphere, retaining some of it, then is frozen in discernible layers over the years.
The researchers have found that methane emissions first began to build during Roman times, then there was another increase around 1,000 years ago. But since the beginning of the industrial age in 1800, there has been a leap in the production of methane from man-made sources, which can be judged from studying the carbon isotope in the methane atom.
It looks like there’s yet another reason to feel bad about eating hamburgers.