- Oct 7, 2011
Do any climate scienists agree with the above opinion?
@Patslatt1 also. It is perhaps worth remembering that before ice cores began to be used to gain information about historical atmospheric content scientists who were convinced that anthropomorphic warming was a fact were quite confident that the new information would confirm their belief that CO2 actually caused global warming. What a surprise then that the ice cores revealed the exact opposite. Warming predated CO2 elevation by centuries. Obviously reeling from this for a while they then responded with a very plausible argument that while CO2 obviously didn't initiate warming it certainly accentuated it once it was initiated and I'm sure they are correct in saying that.AFAIK, NO, they do not.
The paragraph is wrong - the causal cycle for going in an out of ice ages is: Orbital shifts (Milankovitch cycles) cause warming ---> Warming unlocks CO2 ---> More warming ----> Melting ice & more CO2 in the atmosphere --> More water vapour in the atmosphere ---> Even more warming.
Water vapour is a strong greenhouse gas, but is not regarded as a forcing for global warming because it does not mix well in the atmosphere - it precipitates out as rain or snow. CO2 on the other hand, once released, mixes well and stays around for thousands of years, until it is re-absorbed by the earth or the sea.
CO2 is the "control knob" of the global thermostat. Its level in the atmosphere is the main driver of planetary temperature.
However this much more complex situation introduces a massive level of doubt into any attempt to assess what is going on because clearly warming has to be initiated by other factors before CO2 can get to do its work and it's impossible to be any way sure how much warming can be assigned to each process rendering the historical records preserved in the ice much less useful on the face of it because none of it can provide an example of where CO2 elevated temperatures at a time when other forces were not active.
It is noticeable , however, that there is generally a quite close alignment between temperature and levels of CO2 with changes in the former being closely matched by adjustments in the latter-generally taking less than a thousand years which would definitely suggest that there was a substantial and direct causation between elevated levels of CO2 and higher temperatures. The warmists were having a field day.
Not for long however. Ice cores from Vostock initially confirmed the emerging consensus until diligent scientists began to study the real timescales somewhat hidden in the graphs. As you say the cycle is that orbital factors initiate warming with the result that CO2 levels are increased so that at the start of each Ice Age there is an elevated level of CO2 in the atmosphere as a result of the preceding warming period and I'm sure it was at the start of the last Ice Age that the Vostock cores revealed just such a situation with CO2 levels quite similar to what we have today but with an Ice Age raging on for 14,000 years before the CO2 began to fall.
The high CO2 levels did nothing to prevent the Ice Age raging on with plummeting temperatures or so it would seem. Of course you could say that the other forces controlling temperature were acting against the tendency of CO2 to warm the Earth and I've no doubt that this is absolutely true. But it is surely the case that when orbital controllers are switching from forcing a higher temperature to when they are doing the opposite there must be a period of neutral influence during which CO2 might be said to be acting alone. This is not apparent here but perhaps more detailed studies have to be carried out. In any case it seems to be inescapable that CO2 levels offer virtually nothing to mankind as a method of control over the earths temperature. The gas is too weak. You would turn the control knob and nothing would happen most especially when the other controllers are not supportive.