I read this on infowars, but then looked for other sources and found plenty
OK, I changed my first response after reading their study.
The key would be linking cloud cover with global temperatures in a more powerful way.
Climatologist Dr. Roy Spencer has pointed out in his book,
“The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.”
We’ve been discussing the sudden rise in UK and European temperatures in the 1990s, and I was reminded about a study undertaken by Clive Best and Euan Mearns looking at the role of cloud cover four years ago:
Clouds have a net average cooling effect on the earth’s climate. Climate models assume that changes in cloud cover are a feedback response to CO2 warming. Is this assumption valid? Following a study with Euan Mearns showing a strong correlation in UK temperatures with clouds, we looked at the global effects of clouds by developing a combined cloud and CO2 forcing model to sudy how variations in both cloud cover  and CO2  data affect global temperature anomalies between 1983 and 2008. The model as described below gives a good fit to HADCRUT4 data with a Transient Climate Response (TCR )= 1.6±0.3°C. The 17-year hiatus in warming can then be explained as resulting from a stabilization in global cloud cover since 1998. An excel spreadsheet implementing the model as described below can be downloaded from http://clivebest.com/GCC
The full post containing all of the detailed statistical analysis is here.
But this is the key graph:
Figure 1a showing the ISCCP global averaged monthly cloud cover from July 1983 to Dec 2008 over-laid in blue with Hadcrut4 monthly anomaly data. The fall in cloud cover coincides with a rapid rise in temperatures from 1983-1999. Thereafter the temperature and cloud trends have both flattened. The CO2 forcing from 1998 to 2008 increases by a further ~0.3 W/m2 which is evidence that changes in clouds are not a direct feedback to CO2 forcing.
We should note that clouds cannot be modeled properly by global climate models and this causes the biggest uncertainty and wide spread in their projections.
It seems hard for me to believe that the increase in beneficial CO2 and the physics of greenhouse gas warming was NOT responsible for a good chunk of the beneficial warming the last century, regardless of how much was caused by the decrease in clouds during that period.