Thread by @ncdave4life

@Rocky35418823 @JusticeTrudeau @Willard1951 @Climatehope2 @SniemN @AristotleMrs @DenisDaly @ammocrypta @Anvndarnamn5 @BointonGiles @priscian @Veritatem2021 @fischerfischy @Hji45519156 @Jaisans @SeekerTheGreat1 @Michael_D_Crow @ChrisBBacon3 @Mark_A_Lunn @ubique60 @CDMarshall7 @Data79504085 @glinch72 @heinsenberger @Ceist8 @EthonRaptor @JimBowersclimb @RMcgillss @paligap17 @JustThi30117912 @S_D_Mannix @TheDisproof @MaggieL @Willy1000 @AuroriaTwittori @3GHtweets @RushhourP @MartinJBern @gstrandberg1 @ItsTheAtmospher @Jakegsm @EricWil06256732 @DTGvmd @wille99 @PaulDFarrar @KCTaz @Valja46Zhark5 @drochir_thonnuk @paulp1232 We've had CO2 forcing = 58% of a full doubling,
PLUS minor GHG forcings,
PLUS air pollution abatement,
PLUS UHI.
(Let's ignore the last 2.)

Myhre estimated 42% of GHG forcing is from minor GHGs, 58% from CO2.

Kiehl est. 34% from minor GHGs, 66% from CO2.

2/3 CO2 = typical est.

@Rocky35418823 @JusticeTrudeau @Willard1951 @Climatehope2 @SniemN @AristotleMrs @DenisDaly @ammocrypta @Anvndarnamn5 @BointonGiles @priscian @Veritatem2021 @fischerfischy @Hji45519156 @Jaisans @SeekerTheGreat1 @Michael_D_Crow @ChrisBBacon3 @Mark_A_Lunn @ubique60 @CDMarshall7 @Data79504085 @glinch72 @heinsenberger @Ceist8 @EthonRaptor @JimBowersclimb @RMcgillss @paligap17 @JustThi30117912 @S_D_Mannix @TheDisproof @MaggieL @Willy1000 @AuroriaTwittori @3GHtweets @RushhourP @MartinJBern @gstrandberg1 @ItsTheAtmospher @Jakegsm @EricWil06256732 @DTGvmd @wille99 @PaulDFarrar @KCTaz @Valja46Zhark5 @drochir_thonnuk @paulp1232 google.com/search?q=log2(…

If, Rocky says, we've had 1°C of anthropogenic warming, that means only 2/3 °C is from CO2.

If 58% of a doubling yields 2/3 °C, then "practical sensitivity" S is (2/3)/0.58 = 1.15°C/doubling.

@Rocky35418823 @JusticeTrudeau @Willard1951 @Climatehope2 @SniemN @AristotleMrs @DenisDaly @ammocrypta @Anvndarnamn5 @BointonGiles @priscian @Veritatem2021 @fischerfischy @Hji45519156 @Jaisans @SeekerTheGreat1 @Michael_D_Crow @ChrisBBacon3 @Mark_A_Lunn @ubique60 @CDMarshall7 @Data79504085 @glinch72 @heinsenberger @Ceist8 @EthonRaptor @JimBowersclimb @RMcgillss @paligap17 @JustThi30117912 @S_D_Mannix @TheDisproof @MaggieL @Willy1000 @AuroriaTwittori @3GHtweets @RushhourP @MartinJBern @gstrandberg1 @ItsTheAtmospher @Jakegsm @EricWil06256732 @DTGvmd @wille99 @PaulDFarrar @KCTaz @Valja46Zhark5 @drochir_thonnuk @paulp1232 Practical sensitivity S is roughly midway between TCR and ECS. If S is 1.15°C, and ECS = 1.5 × TCR (a typical estimate), that makes:
TCR = 0.92°C
ECS = 1.38°C

See detailed calculations, here:
sealevel.info/practical_sens…

@Rocky35418823 @JusticeTrudeau @Willard1951 @Climatehope2 @SniemN @AristotleMrs @DenisDaly @ammocrypta @Anvndarnamn5 @BointonGiles @priscian @Veritatem2021 @fischerfischy @Hji45519156 @Jaisans @SeekerTheGreat1 @Michael_D_Crow @ChrisBBacon3 @Mark_A_Lunn @ubique60 @CDMarshall7 @Data79504085 @glinch72 @heinsenberger @Ceist8 @EthonRaptor @JimBowersclimb @RMcgillss @paligap17 @JustThi30117912 @S_D_Mannix @TheDisproof @MaggieL @Willy1000 @AuroriaTwittori @3GHtweets @RushhourP @MartinJBern @gstrandberg1 @ItsTheAtmospher @Jakegsm @EricWil06256732 @DTGvmd @wille99 @PaulDFarrar @KCTaz @Valja46Zhark5 @drochir_thonnuk @paulp1232 Those climate sensitivity estimates are obviously far below the IPCC's estimates, and they'd be even lower if we had used Myhre's "58% CO2" estimate.

As you can see, the IPCC's climate sensitivity estimates are incompatible with observations.