gizmo_2655 wrote on Feb 26
th, 2014 at 11:40am:
Sadly George, what most of the pro-AGW crowd don't realise ( I hope, at least) is that IF you are successful in returning temperatures to pre-1850's levels
False premise. Where is it stated anywhere that this is the stated aim?
Quote: you'd also kill off 1/2 or more likely 3/4 of the world's population.
This is an unproven assertion, and can be ignored because it is constructed on a false premise.
Quote:Because the whole AGW idea is based on a false premise, that pre-Industrial Revolution temperatures were 'normal', and they were NOT.
That in itself is a false premise.
You are asserting that the whole of AGW theory is based on pre-industrial levels of CO
2. It is not.
You are asserting this based on the false assumption that mitigating AGW is not just cutting CO2 emissions, but to return CO2 concentrations to pre-industrial levels. Nowhere have you supported this claim with any evidence because no such evidence exists.
You have implied that the temperatures were caused by CO
2 concentrations. The Maunder sunspot minimum has been hypothesised as another contributor to lowered global temperatures during the Little Ice Age.
Digging up black stuff out of the ground and burning it is not normal either. Where did all that coal and oil go after we burnt it? Much of it is still with us in the atmosphere, adding 100ppm to global CO
2 levels over the pre-industrial levels. That this increase is primarily caused by the burning of fossil fuels has been known since the 1960s.
Quote:The temperatures back then (during the Little Ice Age) were massively below average and below optimum for comfortable human existence.
While an interesting argument, it is constructed on a false premise. However, I do note your implied acceptance that atmospheric CO
2 causes warming.
It is unlikely that CO
2 levels will return to pre-industrial levels any time soon, even with the most aggressive remediation possible, so I doubt this is going to be a problem.
However, we do need to be mindful of the causes of the Little Ice Age as well. Even the science of climate change has as an implied assumption for some models that the output of the sun will not change enough to influence the climate, that there won't be large volcanic eruptions, and there won't be other similar external factors in play. One big volcanic eruption can lower global temperatures by 1°C or more for half a decade. A 0.1% reduction in solar irradiance can also lower global temperatures by a similar amount. It doesn't mean the models that do not include these are wrong, just that they do not take these into account as core assumptions.