Glaring Inconsistency in Estimating CO2 vs. Solar Forcing Suggests CO2 Impacts Are Wildly Exaggerated

Spread the love

From about 11,000 to 9,000 years ago the summer solar irradiance absorbed by the Earth’s surface has been estimated to be 40-60 W/m² greater than today from latitudes 40°N to 70°N (Ullman et al., 2015). These values seriously undermine the claim CO2 is the driver of climate change.

Image Source: Ullman et al., 2015

Despite these much higher insolation values, surface temperatures have been estimated to be only a few degrees warmer than today at these latitudes during the Early Holocene.

At 77°N in High Arctic Svalbard, for example, summers were estimated to be 7°C warmer than today from 10,000 to 9,000 years ago due to this higher radiative forcing (van der Bilt et al., 2019).

Image Source: van der Bilt et al., 2019

So if an additional 60 W/m² radiative forcing only elicits a 7°C surface temperature change, the effective sensitivity of a 1 W/m² perturbation to the surface energy imbalance would be about 0.12°C.

This formula (1 W/m² produces 0.12°C surface warming) has been reproduced by NASA and other scientists using satellite observations.

For example, the Mount Pinatubo eruption produced a surface temperature drop of -0.5°C to -0.6°C associated with a -4 W/m² decline in radiative forcing (Self et al., 1993). This is amounts to a 0.12°C to 0.15°C temperature sensitivity per W/m².

Image Source: Self et al., 1993

Other scientists (Douglass and Knox, 2005) have also computed a “0.15 ± 0.06 K/(W/m²)” radiative forcing-temperature sensitivity.

Image Source: Douglass and Knox, 2005

Anthropogenic global warming advocates suggest it takes an increase of 22 ppm CO2 (about 10 years) to produce a surface forcing change of 0.2 W/m² (Feldman et al., 2015).

Image Source: Feldman et al., 2015

So, using this formula, it would take 110 ppm (40-50 years) to produce a positive 1 W/m² surface forcing imbalance. This would only produce a temperature change of, at most, 0.15°C.

Bellamy and Barrett (2007) have likewise suggested the doubling of CO2 could only represent a temperature change of “0.6 – 0.8°C” with the addition of 280 ppm CO2 since the pre-industrial era. This estimate uses the assumption that doubling CO2 produces a 3.7 W/m² top-of-atmosphere (TOA) forcing.

Image Source: Bellamy and Barrett, 2007

Dr. Kimoto (2015), in contrast, suggests using the the surface radiative forcing value (1.1 W/m²) for doubling CO2 from 280 to 560 ppm rather than the TOA value (3.7 W/m²) due to the physical reality of water vapor, not CO2, dominating the infrared absorption in the lower atmosphere. He also computes a surface climate sensitivity of 0.13°C per 1 W/m².

Consequently, with doubled CO2 only yielding a 1.1 W/m² surface forcing perturbation to Earth’s energy imbalance, the climate sensitivity from doubling CO2 from 280 to 560 ppm may only be 0.14 to 0.17°C

Image Source: Kimoto, 2015

In sum, none of these values even remotely suggest CO2 can be a driver of climate change.

via NoTricksZone

By Kenneth Richard on 23. June 2022

This site uses Akismet to reduce spam. Learn how your comment data is processed.