[_5659]

Perhaps you've heard of the "Butterfly Effect" but not a formal definition of the term.

For the issue of predicting weather, the model of weather is "sensitive". The observation metaphor of the "butterfly effect" is that relatively small perturbations to the system have the observed effect of being indistinguishable between relatively large perturbations. We may substitute "small" with "deterministic" and "large" with "non-deterministic".

A summary of this statement would be that initial or past conditions of the system poorly characterize the dynamic and chaotic behavior of nonlinear dynamic systems.

The phrase is drawn from the title of the paper by EN Lorenz:

https://static.gymportalen.dk/sites/lru.dk/files/lru/132_kap...

Somber note: Weather is in fact, becoming predictable, precise and accurate: towards chaos, volatility and instability. Measurement and policy do not adequately address the ongoing issue of climate "change", which may more adequately be defined as climate chaos.