IPCC Overestimate of TSI

From Judith Curry:overconfidence-in-ipccs-detection-and-attribution-part-iv

The level of scientific understanding of radiative forcing is ranked by the AR4 (Table 2.11) as high only for the long-lived greenhouse gases, but is ranked as low for solar irradiance, aerosol effects, stratospheric water vapor from CH4, and jet contrails. Radiative forcing time series for the natural forcings (solar, volcanic aerosol) are reasonably well known for the past 25 years (although these forcings continue to be debated), with estimates further back in time having increasingly large uncertainties.
Based upon new and more reliable solar reconstructions, the AR4 (Section 2.7.1.2) concluded that the increase in solar forcing during the period 1900-1980 used in the AR3 reconstructions is questionable and the direct radiative forcing due to increase in solar irradiance is reduced substantially from the AR3.  However, consideration of Table S9.1 in the AR4 shows that each climate model used outdated solar forcing (from the AR3) that was assessed to substantially overestimate the magnitude of the trend in solar forcing prior to 1980.  The IPCC AR4 states: “While the 11-year solar forcing cycle is well documented, lower-frequency variations in solar forcing are highly uncertain.”  “Large uncertainties associated with estimates of past solar forcing (Section 2.7.1) and omission of some chemical and dynamical response mechanisms make it difficult to reliably estimate the contribution of solar forcing to warming over the 20th century.”

Natural Puritanism

What I posted at Judith Curry:


Don

I think you get this mostly right. I for one am struck by the religious attributes of AGW.

I also think we (humanity) have a tendency towards puritanism: that is  moral righteousness and intolerance of "indulgent" enjoyment (sinning); plus a desire to impose this viewpoint on everyone else. In our secular society I think our sins have moved from the religious domain to the natural: health and environment. And these ideologies are backed up by "science", that is scientific papers highlighting the dangers our modern society poses for health and environment. More disturbing some (much?) of this literature seems designed to support a pre-determined policy agenda.

Price of Gas

Christopher Booker - The IPCC declares Greenpeace in our time

Another of the scores of sites across Britain where wind farm plans are now arousing huge anger and unhappiness among locals is the Althorp estate in Northamptonshire, where Earl Spencer is hoping that a French company, EDF, will be allowed to spend £2.5 million to erect 13 2MW turbines, towering 385ft over the Vale of Avon Dassett. These will provide their owners with subsidies of around £650,000 a year, for producing a quantity of power so small that its fluctuating contribution to the grid will scarcely register. Compare this to the nearly 900MW output of the £400 million gas-fired power station recently opened near Plymouth and it can be seen that the capital cost of these wind farms, for the puny amount of electricity they produce, is around 10 times as much. The expense of the Welsh Assembly's £2 billion plan to build 800 turbines, up to 415ft high, across a vast stretch of mid-Wales, plus 100 miles of pylons to connect them to the grid, will be a staggering 15 times higher than would be needed to produce the same amount of power from gas, without subsidy.

Some back of the envelope calculations, if we wanted to power UK with gas and wind, with wind at 40% penetration (I'm assuming that's at 40% of expected capacity rather than nameplate capacity): calcs