To what extent are temperature levels changing due to greenhouse gas emissions?

Even if recent recorded temperature variations should turn out to deviate from previous variation patterns in a systematic way it is still a difficult challenge to establish how much of this change is due to increasing man made emissions of carbon dioxide (CO2) and other greenhouse gases.

From NOT A LOT OF PEOPLE KNOW THAT

By Paul Homewood

A new Norwegian paper has found that the effects of man-made CO2 emissions are not strong enough to explain global warming in the last 200n years, implying that natural factors must play a large role:

The study contains a lot of statistical analysis. But the bottom line is that Global Climate Models, GCMs, do not track past temperature changes at all well:

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