From Phillip Magness, The ‘Climate Science’ MONIAC Machine

Economics has fortunately moved well beyond the days of the hydraulic MONIAC machine and its underlying assumptions about economic causality. We have since learned – sometimes the hard way – that the economy is simply too complex to causally map out as a precise system of policy levers that could shape production and commerce with reliable and predictable outcomes. Forecasting took a similar turn as well, moving away from drawing out trend lines that were backfilled to fit the predictions of overly simplified causal relationships. In its place, economics adopted the statistical conventions of modern forecasting tools with their associated cautions against making long range predictions and claims of precision.

In a strange way, modern climatology shares much in common with the approach of 1950s Keynesian macroeconomics. It usually starts with a number of sweeping assumptions about the relation between atmospheric carbon and temperature, and presumes to isolate them to specific forms of human activity. It then purports to “predict” the effects of those assumptions with extraordinarily great precision across many decades or even centuries into the future. It even has its own valves to turn and levers to pull – restrict carbon emissions by X%, and the average temperature will supposedly go down by Y degrees. Tax gasoline by X dollar amount, watch sea level rise dissipate by Y centimeters, and so forth. And yet as a testable predictor, its models almost consistently overestimate warming in absurdly alarmist directions and its results claim implausible precision for highly isolated events taking place many decades in the future. These faults also seem to plague the climate models even as we may still accept that some level of warming is occurring.