/sci/ - Science & Math

>>11392357
I'm 100% right. 300 to 400 ppm CO2 results in insignificant greenhouse effect.

https://wattsupwiththat.com/2013/05/08/the-effectiveness-of-co2-as-a-greenhouse-gas-becomes-ever-more-marginal-with-greater-concentration/

According to well understood physical parameters, the effectiveness of CO2 as a greenhouse gas diminishes logarithmically with increasing concentration and from the current level of ~390 ppmv, (parts per million by volume). Accordingly only ~5% of the effectiveness of CO2 as a greenhouse gas remains beyond the current level.

This inconvenient fact is well understood in the climate science community. It can be accurately modeled using the Modtran program maintained and supported at the University of Chicago.

The logarithmic diminution of the effect of CO2 is probably the reason why there was no runaway greenhouse warming from CO2 in earlier eons when CO2 levels were known to be at levels of several thousands ppmv.


Remarkably, IPCC Published reports , (TAR3), do actually acknowledge that the effective temperature increase caused by growing concentrations of CO2 in the atmosphere radically diminishes with increasing concentrations. This information is in their report. It is well disguised for any lay reader, (Chapter 6. Radiative Forcing of Climate Change: section 6.3.4 Total Well-Mixed Greenhouse Gas Forcing Estimate).

The diminishing percentage effectiveness of CO2 as a greenhouse gas as acknowledged by the IPCC and its concomitant diminishing temperature effect are as follows:

increment cumulative

0-100 ppmv: according to David Archibald / Modtran data ~2.22°C ~2.22°C

100-200 ppmv: plants die below this level of CO2 +~0.29°C ~2.51°C

200-300 ppmv: noted as the preindustrial CO2 level +~0.14°C ~2.65°C

300-400 ppmv: current level IPCC attributes all as Man-made +~0.06°C ~2.71°C

400-600 ppmv: business as usual till 2100 +~0.08°C ~2.79°C