'Hawaii will be a hotter place, with fewer cooling trade winds and more drought, fewer waterfalls and forest streams. Sea levels will rise, meaning there will be fewer beaches and more flooding as the coast erodes.'
The IPCC’s AR5 attribution statement: 'It is extremely likely that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic increase in greenhouse gas concentrations and other anthropogenic forcings together. The best estimate of the human induced contribution to warming is similar to the observed warming over this period.'
The reasoning process used by the IPCC in assessing confidence in its attribution statement is described by this statement from the AR4: “The approaches used in detection and attribution research described above cannot fully account for all uncertainties, and thus ultimately expert judgement is required to give a calibrated assessment of whether a specific cause is responsible for a given climate change.'
Curry: 'The attribution statement itself is at best imprecise and at worst ambiguous: what does “most” mean – 51% or 99%? Whether it is 51% or 99% would seem to make a rather big difference regarding the policy response.'
'The IPCC’s attribution statement does not seem logically consistent with the uncertainty in climate sensitivity.'
'I am arguing that climate models are not fit for the purpose of detection and attribution of climate change on decadal to multidecadal timescales.'
'The one thing that they do not want to have to admit is that they exaggerate the amount that the earth’s average temperature will increase as a result of human greenhouse gas emissions. If the models are overheated, then so too are all the projected impacts that derive from the model projections—and that would be a disaster for all those pushing for regulations limiting our use of fossil fuels for energy.
It is clearly not a good situation for climate models when even a sustained temperature rise equal to the fastest yet observed (Scenario 3) still leads to complete model failure within two decades.'