The science of climate change skepticism

If CO2 is but one of several causes of warming over the past decades, then current climate models almost certainly have to be exaggerating future warming. Only by attributing all of the past warming to CO2 can catastrophic future warming forecasts be justified. In fact, even the 0.7C of measured historic warming is well under what the climate models should have predicted for warming based on past CO2 increases and their assumed high sensitivity of temperature to CO2 levels. In other words, to believe a forecast of, say, 5C of warming over the next 100 years, we should have seen 2C or more of warming over the past century.

This is why the IPCC actually had to make the assumption that global temperatures would have fallen naturally and due to other manmade pollutants over the past several decades. By arguing that without man’s CO2 the climate would have cooled by, for example, 0.5C, then they can claim past warming from CO2 as 1.2C (the measured 0.7C plus the imaginary 0.5C). Anyone familiar with how the Obama administration has claimed large stimulus-related jobs creation despite falling employment levels will recognize this approach immediately.

Despite these heroic efforts to try to find observational validation for their catastrophic warming forecasts, the evidence continues to accumulate that these forecasts are wildly overstated.