Sentences with phrase «structural uncertainties in observations»
The large structural uncertainties in observations hamper our ability to determine how well models simulate the tropospheric temperature changes that actually occurred over the satellite era.
http://www.realclimate.org/
There were two strands to our critique: i) that the statistical test they used was not appropriate and ii) that they did not acknowledge the true structural uncertainty in the observations.
This is of course the same Douglass et al paper that used completely incoherent statistics and deliberately failed to note the structural uncertainty in the observations.
Not exact matches
There are basically two key points (explored in more depth here)-- comparisons should be «like with like», and different sources of uncertainty should be clear, whether uncertainties are related to «weather» and / or structural uncertainty in either the observations or the models.
Because the differences between the various observational estimates are largely systematic and structural (Chapter 2; Mears et al., 2011), the uncertainty in the observed trends can not be reduced by averaging the observations as if the differences between the datasets were purely random.
let's take this to an extreme... suppose that internal variability is zero... then the «within group» s.d. is zero... suppose that models agree pretty well with each other and observations fall within the tight band of model projections... then by steve's method you create the average of models and call it a model... with an s.d. of zero... show that the model falls outside the observational s.d.... proclaim that the model fails... claim that this is a test of modelling... hence extrapolate that all models fail... even though observations fall slap bang in the model range... this result is nonsensical... per tco it isn't how models are used... where's structural uncertainty?
The two obvious contributors to the uncertainty are the structural biases in the proxies and the sampling error from estimating GAST from 5 - 61 SST observations.