PDQ
You mention that the only thing all/both sides agree on is that average temperature has risen by about a degree. I think the fixation with 'average temperature' rise and the calculation thereof has only served to muddy the arguments. If you think about what measuring the average temperature of the world actually implies you have to do, with all the huge changes in day/night and summer/winter temperatures, its not surprising that its hard to get good data.

However there are a number of things that most people should be able to agree on, and I'd be interested to hear people's comments

1. Carbon Dioxide absorbs heat from solar radiation. The physics of that has been pretty clear for about 100 years, thanks to Arrhenius and others.

2. Humans are burning a lot of hydrocarbon fuels that have increased the amount of carbon dioxide in the atmosphere.

3. You would expect the heat absorbed by the extra carbon dioxide has to go somewhere.

4. Our global climate should be affected by the extra heat - there is more energy driving the fronts and cyclones around

5. Carbon dioxide is clearly not the only thing driving changes in global climate - there are solar variations, Milankovitch cycles etc. In particular we don't know nearly enough about the role of methane as a greenhouse gas, and the impact of aerosols in mitigating the greenhouse effect.

6. You can't make any useful conclusions about the changes in global climate from individual episodes of good/bad weather - weather is a chaotic system (especially here in the northern UK), which means tiny changes in the starting conditions have huge changes in the final weather outcome. Indeed chaos maths was first discovered by a meteorologist.

7. Changes in average temperature don't kill you - its the possible increase of extreme events that's damaging. Its a problem if a 1 in 300 year flood actually happens every 25 years.

8. At some point we will have to move to a renewable non-fossil fuel economy so it makes sense to invest in these technologies. Given the sources of much of the world's oil and gas there are probably good political reasons for doing so.

9. The cost of converting large quantities of the world's power supply to renewables/nuclear could be huge (the International Energy Authority are talking about a trillion dollars a year for the next thirty years!), but its not dissimilar to the amounts Governments are spending/talking about spending to reflate the world economy out of the current recession/depression.

10. Although a lot of attention is focused on the impact of transport (from SUV's to air travel), actually the biggest source of greenhouse gases is the heating lighting and air-conditioning of buildings (about 40% in the UK). Reducing the carbon footprint of buildings can usually be achieved by decreasing their energy consumption - in other words it can save you money to reduce your emissions. There are lots of easy gains here - there is typically a 500% difference in energy consumption between the best and worst office buildings for example. So it makes sense to 'turn the lights off when you go home'.

I don't know about every point but I would hope that many of the contributors to this debate would actually agree with much of the above.

As a personal note I have sufficient technical background to understand some of the climate science but am not a practicing researcher in the area. I used to work for an oil company, and indeed still own shares in it. I do produce a number of studies into the economic impact of global warming and some of the amelioration strategies.

Looking forward to hear your comments.
KP