[avandonk]

Yes CO2 concentration does lag temperature rise by about 800 years. This is also well understood as the oceans and ground warm they liberate CO2 this then adds to the warming caused by solar variation. This accounts for about 60% of the then temperature rise not solar variation.

The current situation is that we for the first time in history have by burning fossil fuels have taken CO2 levels way past any historic value.

Solar variation is not the major cause of current temperature rise. The situation is even worse if you take into account that every glacier on Earth is retreating. The high levels of CO2 are also raising the pH of the oceans to the extent that any organism that forms calcium carbonate shells for protection are not doing as well as they were doing it in the past. Where do you think limestone comes from. There are also huge amounts of CO2 fixed in clathrates on the colder parts of the oceans floor. If these clathrates warm up there will be a run away effect. The CO2 and methane now held in the frozen arctic tundra will also be liberated. This will make our puny efforts by burning fossil fuels look like a little blip. Trouble is we have set off this chain reaction.

Once the tipping points have been reached there is no going back. By tipping points I mean the negative feedback systems have been overcome and positive feedback then cuts in.

We ignore it at our peril.

As a small aside if it was not for the 200ppm of CO2 the average temperature of the Earth would be -17C.

Bert