Reposted by NOT MANY PEOPLE KNOW THAT
By Paul Homewood
Ken Gregory sent me his latest paper on the social costs of carbon.
If he’s right, it reverses all arguments for spending trillions of dollars on a nonexistent problem:
Social costs (benefits) of carbon dioxide from FUND
with corrected temperatures, energy and CO2 fertilization
By Ken Gregory, P.Eng. May 26, 2021
Climate policies such as carbon taxes are set by governments using social carbon cost (SCC) values calculated by economic computer programs called integrated valuation models (IAM). FUND is the most complex of the IAMs, which links emission scenarios and models for the economy, climate and impacts for 16 world regions. Unfortunately, the climate component of FUND, which determines temperature, is flawed because it assumes that the deep oceans are instantly in temperature equilibrium with the atmosphere with no time lag when the equilibrium climate sensitivity (ECS) is 1.5 ° C or less. The FUND model runs too warm compared to climate models.
The ESC can only be estimated using the energy balance method, which compares the climate actuators with historical temperature records. The Lewis & Curry 2018 paper presents estimates from ECS with uncertainty analysis. The analysis was flawed in that natural climate change was not taken into account and no correction was made to remove the urban heat island effect from the temperature record. With these adjustments, the likely range of the ECS based on energy balance calculations using actual historical temperatures is 0.76-1.39 ° C with a best estimate of 1.04 ° C.
The energy influencing components for the FUND’s space heating and cooling expenses are very poor. The change in spending in temperatures does not reflect the published spending data for the United States. A paper by Peter Lang and me shows that a 3 ° C rise in temperature would reduce US energy spending by 0.07% of gross domestic product (GDP), but the FUND is forecasting an increase in spending of 0.80% of GDP, if not temperature-related factors are recorded constant. A study by Dayaratna, McKitrick and Michaels (D, M & M 2020) on the CO2 fertilization effect and the FUND agricultural component shows that the FUND CO2 fertilization effect should be increased by 30%.
I created a modified version of FUND that includes a 2-box ocean climate model that is precisely tailored to the temperature profile of climate models. I replaced the faulty space heating and cooling components with new components that match the empirical data for heating and cooling from the US and increased the FUND CO2 fertilizing effect by 30%. The net social benefit of CO2 emissions is calculated using the ECS probability distribution. The results show that the net benefits from CO2 emissions are US $ 11.74 and US $ 8.41 / tCO2 at a discount rate of 3% and 5%, respectively.
Agriculture dominates the SCC values, which account for more than 100% of the net benefits of CO2 emissions. The mainstream media is fixated on storms and sea level rises, which are insignificant. The data shows that climate change is quite beneficial with the CO2 fertilization effect, so policies that cost trillions of dollars to reduce CO2 emissions are wrong. See the report here.