OK. Let us continue with the 2007 Report. (YES< this the REAL one)
But, even though the linchpin of the AGW hand waving is the Greenhouse, there is no proposal as to why that occurred in the first place, after the Oxygen Age began, or even if it did. More importantly, there is no prediction at all of how the Earth managed to recover if, it happened at all.
And there is always the discussion, from the beginning of the UN-cetainty and the lack of data.
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-7.html
6.7 Concluding Remarks on Key Uncertainties
Knowledge of climate variability over the last 1 to 2 kyr in the SH and tropics is
severely limited by the lack of palaeoclimatic records. In the NH, the situation is better, but there are important limitations due to a
lack of tropical records and ocean records.
Differing amplitudes and variability observed in available millennial-length NH temperature reconstructions, and the extent to which these differences relate to choice of proxy data and statistical calibration methods,
need to be reconciled. Similarly, the
understanding of how climatic extremes (i.e., in temperature and hydro-climatic variables) varied in the past
is incomplete.
Lastly, this assessment
would be improved with extensive networks of proxy data that run right up to the present day. This
would help measure how the proxies responded to the rapid global warming observed in the last 20 years, and it
would also improve the ability to investigate the
extent to which other, non-temperature, environmental changes may have biased the climate response of proxies in recent decades.
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That last, we have to add, IF ANY EXTENT. And that is the problem and that is bad science.
This began with a non-scientific assumption of Greenhouse. And it jumped from gas to gas, and now CO2. And it was ignored by real Science, until now. And now the real thinkers are being the backlash.
The models will be hard pressed to show much warming lately and will find again it is impossible to show AGW.