If there is such a feedback effect then this is required to be proved: the article cannot merely assert it. And on the face of it it is unlikely: here's why. The increase in greenhouse effect from CO2 is much weaker than from (e.g.) water vapour, as CO2 traps only a small band of wavelengths. Double the amount of CO2 and the amount of greenhouse trapping due to CO2 does not double - still less does the amount of total heat trapped by all greenhouse effects. Therefore the climate system is fundamentally stable with respect to CO2. How then can there be a runaway feedback?
Fact: This was once the case, but it has been resolved now that initial measurement errors have been corrected.
It's been "resolved". Uh-huh. The article needs to post some graphs: temperature at height with a time variation. Remember the requirement of AGW is that the warming should happen at height first, then transmit to the ground.
Claim: Temperatures rose for the first part of the century, then cooled for three decades before warming again. There is no link to carbon dioxide
Fact: Temperatures did follow this pattern, but again there is a good explanation. The mid-century effect fall came about chiefly because of sulphate aerosols – particles that have a cooling effect on the atmosphere.
The programme showed an excellent correlation between solar sunspot activity and temperature change. Unless earth's temperatures are driving sunspot activity its difficult to see why this correlation ocurrs.
MY QUESTIONS:
Why did the temperature rise above current levels in the Mediaeval warm period? Was it perhaps the effect of Henry the First's heavy industrialisation of Britain?
Why did Europes "little ice age" coincide with the period of the Maunder Minimum (1645 to 1715 AD). Was it perhaps due to the effect of sulphur aerosols? Or is it directly correlated to solar activity? Note to Freepers: the Maunder Minimum is named for a prolonged period of zero sunspot activity - of reduced heat output by the sun.
There is no runaway feedback. CO2 concentrations top out at around 280 ppm during interglacials. The positive feedbacks are important for the transition out of a glacial period (and they are negative feedbacks for the transition INTO a glacial period!!!!).
Remember the requirement of AGW is that the warming should happen at height first, then transmit to the ground.
Global warming takes place because atmospheric CO2 absorbs longwave radiation emitted FROM the surface (the surface converts incoming shortwave (solar) radiation into longwave IR). Your statement doesn't make sense.
The programme showed an excellent correlation between solar sunspot activity and temperature change.
See the initial link in point #2 of my profile. Why did the temperature rise above current levels in the Mediaeval warm period?
According to the National Academy of Sciences assessment of the Mann "Hockey Stick", sufficient quantification of proxy climate data is unavailable for a definitive comparison of MWP temperatures to now. Qualitative indicators demonstrate that the MWP was approximately as warm as now. (The Little Ice Age was definitely colder than either.)