Reality Clouds climate crystal balls
It is obvious that in any real-life activity it is impossible to wholly rely on such deductions. The reason is at least that the parameters of the studied phenomena are never known absolutely exactly and a small change in parameters (for example, the initial conditions of a process) can totally change the result. Say, for this reason a reliable long-term weather forecast is impossible and will remain impossible, no matter how much we develop computers and devices which record initial conditions.
In exactly the same way a small change in axioms (of which we cannot be completely sure) is capable, generally speaking, of leading to completely different conclusions than those that are obtained from theorems which have been deduced from the accepted axioms. The longer and fancier is the chain of deductions ("proofs"), the less reliable is the final result.
Vladimir Arnold..
In what could be perceived as an about turn in reporting the BBC has separated the "forecasts" for climate to the "reality" that the observations have shown that global warming has stopped
.
This headline may come as a bit of a surprise, so too might that fact that the warmest year recorded globally was not in 2008 or 2007, but in 1998.
But it is true. For the last 11 years we have not observed any increase in global temperatures.
And our climate models did not forecast it, even though man-made carbon dioxide, the gas thought to be responsible for warming our planet, has continued to rise.
So what on Earth is going on?
Climate change sceptics, who passionately and consistently argue that man's influence on our climate is overstated, say they saw it coming.
They argue that there are natural cycles, over which we have no control,
As we see with quasiperiodic systems the return to a “previous climate” state is regularly seen in the NAO.,PDO and IPO. These are sates with long periodicity for a climate regime of warmer then normal or cooler then normal climate states.
The ability for a recurrent periodic state such as the PDO or an inverse temperature “state” is in essence a binary transformation or bifurcation.. The transformation as a velocity inversion has the same effect as a time inversion, (v to - v ) (t to - t )
A fundamental consequence of the aperiodicity of the atmospheric and climate dynamics is the well-known difficulty to make reliable predictions.Contrary to simple periodic or multiperiodic phenomena(such as eclipses,tides ets) for which a long term prediction is possible, predictions in meteorology and climate are limited in time.
The most plausible (and currently admitted) explanation is based on the realization that a small uncertainty in the initial conditions used in a prediction scheme (usually referred as error") seems to be amplified in the course of the evolution. Such uncertainties are inherent in the process of experimental measurement, The uncertainty being in the “closeness of the boundary to the point of bifurcation, and the error in linear equations.” An important aspect discussed by Arnold and Shulinov.
As the “natural variability” and inverse regimes are often accompanied by inverse temperature states always and everywhere(except in gcm predictions) explanations are clearly in order.