On Thursday, 6 March 2014 20:58:36 UTC, Lawrence Jenkins wrote:
On Thursday, 6 March 2014 20:50:23 UTC, John Hall wrote: In article , Lawrence Jenkins writes: snip Could it be that 80ppm that humans have put into the atmosphere has reached a saturation point where it no longer has any effect on catastrophic warming. I think that the short answer is: no, it couldn't. -- John Hall

So its a linear process doubling co2 twice the effect.

There is a temperature response to a CO2 increase. It doesn't have to be linear for there to be a response. In fact it is known that the response is *not* linear but that doesn't negate the view that excess CO2 causes warming.

Tudor Hughes, Warlingham, Surrey.