Earth ECS Upper Limit using Modified Energy Budget Methods and Trend Analyses v.3b (2406.11869v5)

Abstract: Earth global and regional effective thermal "conductance" G(eff) (in (W/m^2)/C and often labeled lambda in climate research) and the related Equilibrium Climate Sensitivity (ECS) are evaluated by applying a modified version of the Energy Budget method, and using data only after 1970. By removing Periodic Interfering temperature components (using a novel PIR process) and applying high frequency filtering, an extraordinarily near linear temperature response is revealed, enhancing accurate G(eff) calculation and avoiding the pre-1970 aerosol forcing and ocean energy per area (E*) absorption uncertainties. A formal/empirical method is used to determine more reliable values of Q(t)=d[E*(Ocean.energy)]/dt . Using NOAA data, and after PIR, it is shown that: 1) The Energy Budget Method can be realistically applied to the Ocean and Land regions independently, 2) the effective volcanic forcing is <= 1/5 the IPCC AR5 estimate, 3) the "historical" 1980-2020 ECS(eff) values for Global, global Ocean, and global Land regions values are <= 2.16, 1.69, 2.96 C/2xCO2 respectively; where the updated IPCC AR5 orthodox independent global Forcing value of 0.4 (W/m^2)/Decade and F/2xCO2= 3.7 W/m^2 were used. Uncertainty is about 10%. The Global average ECS(true) value of <= 2.10 C is 70% of the IPCC AR6 ECS estimate of 3.0 C, but 127% of the ECS(eff) value reported by Lewis (1.66 C). The estimated oceans average TCR/ECS ratio = 0.71 and the global average TCR/ECS ratio = 0.83, and ECS(land)/ECS(Ocean) = 1.78 . [Results using HADCRUT temperature data instead are similar, but 6% "cooler" over land, and 8% "warmer" over oceans.] A simplified physically realistic formal/empirical Coarse 2-D Global Climate Model is derived wherein variation of Geff(t) until equilibrium (i.e. "pattern effects") are proven to be negligible or "cooling", using these Methods. And so it is likely ECS(true)<= ECS(eff).