Wow, I opened a can of worms with that one...
Haven't had time to read all responses (and probably won't get time), but I trust all is fair and people are remembering to "play the ball, not the man" so to speak.
Hi Adam!
I think it's all healthy debate.
I would probably be much less anxious to publicly label someone so highly qualified as stupid and ignorant (even if I disagreed with their opinion) but each to their own

It is water off a duck's back (that's provided the earth doesn't dry out and burst into flames tomorrow due to global warming

)
Um, so what she said was:
She agrees that climate change is real and is happening;
She doesn't know what will happen (you've stressed the whole 'maybe not much will happen' but have conveniently ignored the whole 'maybe a lot will happen'; and
She agreed that more carbon dioxide will change something.
South_Aussie_Hiker, what exactly are you unsure about? Are you not sure, or are you just going to wait for twenty years and then say 'Yep, that's exactly what I said would happen'?
Hi La_Pahina.
I'd like you to show me on my previous posts where I (or my colleague) ever said nothing should be done. I want to make it absolutely clear that I think we should act to reduce our carbon emissions and that I'm actually a staunch supporter of a carbon tax (for several reasons).
What I meant by "I'm unconvinced" was that I don't believe that the current global warming trend is in fact entirely (or largely) a function of human activity, and that if it were to continue the effects would be no rain/no snow/extreme freak weather/destruction of huge ecosystems.
Do I think unsure should mean we don't do anything? ABSOLUTELY NOT.
The parallel drawn earlier with stratospheric ozone is quite interesting.
The scientists at the time identified the problem (largely CFC related), and the fix very accurately.
Interestingly, some were also of the opinion that the ozone which had been lost would never EVER return and the levels would spiral downwards quickly to nothing, even if the cause of the depletion was completely and immediately rectified.
Luckily, this proved incorrect and current estimates show the ozone layer should have returned to historic levels in the next 40-60 years.
Why is this interesting? Well the problem and solution were reasonably well understood, but the end result (ie permanent versus temporary effect) was dead wrong. I agree the greenhouse effect exists, and I agree eliminating human carbon emissions would solve OUR contribution to warming, but I don't accept that the current rate of increase in average global temperatures is PURELY a result of human carbon OR that the current rates could not have occurred completely naturally. I also don't accept that a higher average global temperature will definitely reduce rainfall/snow.
I've been to a meteorology lecture where the lecturer spent the first half of the lecture proving higher average temp = more rain, and then with a perfectly straight face, spent the second half of the lecture proving the absolute opposite. It was interesting to say the least.
This statement is flat out untrue. There are no historical or proxy records that show climate changes at the same rate as what has been observed in recent decades. None. Zip. Nada. Anybody who found one would be instantly famous in the climate science community. That's not to say that there cannot have been changes at the same rate as the present, just that there is no evidence to support such a claim. Saying it's been seen "time and time again" is just not true.
I know I'm probably wasting my breath (or finger muscles!) here Alliecat, but I do think it important here to metion that decades really mean diddly squat here. My colleague was adament that over much larger periods of time (ie tens of thousands of years) that even relatively simple methods (I think she mentioned ice core/earth core CO2 sampling, but don't know if was in relation to this particular point or something else) had shown much higher rates of increase/decrease in global temperature. If I am to get in touch with her again (she has moved home), I'll be sure to bug her for more info on this and see if I mis-understood her.
As you have been employed in statistical analysis of climate change, If my comment
Whenever something like climate change comes along, you have to first exclude anyone who has anything personal to gain by supporting one way or the other.
hit a nerve with you, then I apologise.
It is good to see someone so passionate about our planet.