But a longer term trend can also be seen - the graph is steadily rising.  And the start of the rise can be seen to be roughly around the time of the beginning of the Industrial Revolution; ie when the burning of fossil fuels really took off.  The graph also shows that there is a corresponding change in average air temperature, which shows the annual trend and the long-term rise.  Now, even before modern man, there were variations in CO2 concentrations.  We know this by measuring CO2 concentrations which became trapped in ice cores, and also by studying tree growth rings.  The question is - is the current rise in CO2 and air temperature man-made, or would it have happened anyway?  The scientists are fully conscious that it may be a natural variation; work is still being done on separating out the natural changes from the man-made changes.  It is not possible to go into great detail, but this is an outline of what it going on in the scientific community.

Millions of data are being taken.  Often automatic remote measurement stations record, CO2 concentrations, temperatures at all altitudes, wind speeds, rainfall etc.  The amount of data collected is truly staggering.  The scientists use these data to check their models.

Other planets are observed to study global warming.  For example, measurements of temperatures on Venus taken from earth and by probes show us that the planet is a lot hotter than it would be if it did not have an atmosphere.  Having an atmosphere is like putting a greenhouse around a planet - it keeps it warm.

Computer models are run on super-computers around the world.  These numerical models take into account many phenomena - sunlight energy reaching us, heat energy radiating back out to space, absorption of CO2 by plants, movement of CO2 between the atmosphere and the oceans, and of course the models consider how much CO2 is released by humans burning fossil fuels.  The scientists are constantly improving the models.  The models are tested again and again; to check their effectiveness, the output from each test is compared against the field data.  When the agreement is good the scientists know the model is working well.  When the model is working, it is used to test the future - and when the computer programs are run at today’s levels of CO2 release, they show that Earth is going to warm up.  Global warming.  The scientists publicise their findings through the IPCC - the Inter-Governmental Panel on Climate Change.  The IPCC has concluded that the observed rises in CO2, global temperatures and the resulting changes in weather patterns are probably caused by human actions.  

So given that Terry’s comments fly in the face of the data and the conclusions of many trained minds, and given that Terry is a disc jockey: not a scientist,  the question is why does he say those things?  The answer is that Terry’s perception of the world is not accurate, he is suffering from delusion.  Terry is in denial of his conscience.  Terry finds it convenient to dismiss the truth, as the truth exposes that he is not taking adequate responsibility to care for his world.  Suppressing the conscience with falsehoods is a very common disorder.  Unfortunately, Terry is in a position where he can pass on his delusions to his audience.  There will be many people in the UK who want to hear Terry ridicule environmentalists, so that their consciences may also be suppressed.  Many people