We have now reached a point in our enquiry where we have all the answers but one. We have seen that over the geological ages the climate has varied from hothouse to ice-house, and that the atmosphere has varied in parallel, from CO2-rich to CO2-poor. We have seen that small perturbations in the global temperature are magnified by several feedback mechanisms. We have seen that during the 20th century and into the 21st, both the temperature and the atmospheric CO2 have increased, and we have seen the connection between the two. What we have not yet seen is the source of the CO2.

WHERE DID THE CO2 COME FROM?

The very accurate daily analyses of air from around the globe and from air trapped in ice have unequivocally shown us that CO2 and methane have increased in our atmosphere over the past 200 years. We know how it is that these gases can affect the climate, so we need to find out where they come from and why they are increasing.