@flimsin@Peters_Glen@ClimateAdam@MichaelEMann@FrediOtto Yes, I was going to mention that more generally there is a misunderstanding that the political goals for limiting warming to round(fish) numbers (1.5C, 2C) represent some sort of physical threshold, beyond which feedbacks suddenly kick in or all is lost in some other way >
@flimsin@Peters_Glen@ClimateAdam@MichaelEMann@FrediOtto And as a variant on that, some folk seem to think that there is some sort of physical significance to warming of 1.5C, 2C at smaller scales, eg. individual countries. These numbers were established as targets to keep *global* warming below (+2C) or to try to limit to (+1.5C)
@flimsin@Peters_Glen@ClimateAdam@MichaelEMann@FrediOtto There's also a particularly pernicious conspiracy theory that climate scientists (especially those in government institutions) are deliberately hiding some sort of terrible "truth" from the public (that things are even worse than we say)
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It doesn't even need one of the highest emissions scenarios. RCP6.0 (considered likely with current policies) gives that much warming fairly near the middle of the range in our latest projections
They label it 3C but that's the central estimate, & I don't think it accounts for uncertainties in carbon cycle feedbacks like the UKCP18 probabilistic projections do
Yes global warming of 4˚C this century is quite possible, & would bring massive risks to life & society (heatwaves, coastal & river flooding, drought etc)
Ilan does not seem to dispute that - he just says (correctly) that societal outcomes can't be predicted >
@PlanB_earth@IlanKelman@thetimes@bwebster135 Ilan's right that the DARA claim of 400,000 deaths per year due to climate change can't be verified - they don't give the source. It's possible that they have mis-typed a reference as there's a similar one in their bibliography, but even that doesn't seem to support the number >
@PlanB_earth@IlanKelman@thetimes@bwebster135 This is not to say that the number is less. It might be more. We just don't know, and IMO quoting numbers that can't be substantiated is just not useful because it undermines the concept of rigorous analysis (and this number is being quoted as if it's somehow authoritative) >
The latest forecast from the World Meteorological Organization @WMO, led by @metoffice, suggests that over the next five years there is a 24% chance of the global average temperature exceeding 1.5C above pre-industrial levels for at least one year
This is a reminder of rising temperatures, but it would not mean that the long-term Paris goal to limit warming to 1.5C will have been breached
The 1.5C limit refers specifically to long-term human-caused warming and not the added effect of natural fluctuations in the climate
The blue band shows the WMO forecast for the next five years, with the darker blue shading indicating higher probabilities.
Annual global temperatures are likely to be > 1C warmer than pre-industrial in each of the coming five years – and very likely within the range 0.91-1.59C
I see that this scientist (Cath Senior, our Head of Understanding Climate Change) is not quoted until paragraph 16 of the article, whereas Johan Rockström (not a climate modeller, and not involved in developing, evaluating or using this model in any way) is quoted in paragraph 5