Can you please clarify exactly which articles?
Ghil 2008 explains the problem nicely (this was an invited paper to the 250 euler conference ) CLIMATE DYNAMICS AND FLUID MECHANICS:
NATURAL VARIABILITY AND RELATED UNCERTAINTIES 2008.
Parts of interest are
We have shown, for a stochastically perturbed Arnol’d family of circle maps, that noise can enhance model robustness. More precisely, this circle map family exhibits structurally stable, as well as structurally unstable behavior. When noise is added, the entire family exhibits stochastic structural stability, based on the stochastic-conjugacy concept, even in those regions of parameter space where deterministic structural instability occurs for vanishing noise
Clearly the hope that noise can smooth the very highly structured pattern of distinct behavior types for climate models, across the full hierarchy, has to be tempered by a number of caveats. First, serious questions remain at the fundamental, mathematical level about the behavior of nonhyperbolic chaotic attractors in the presence of noise. Likewise, the case of driving by nonergodic noise is being actively studied
Second, the presence of certain manifestations of a Devil’s staircase has been documented across the full hierarchy of ENSO as well as in certain observations Interestingly, both GCMs and observations only exhibit a few, broad steps of the staircase, such as 4 : 1 = 4 yr, 4 : 2 = 2 yr, and 4 : 3 _= 16 months.
and theorem 3b
Before applying this result, let us explain heuristically how a Devil’s staircase step that corresponds to a rational rotation number can be destroyed” by a sufficiently intense noise. Consider the period-1 locked state in the deterministic setting. At the beginning of this step, a pair of fixed points is created, one stable and the other unstable. As the bifurcation parameter is increased, these two points move away from each other, until they are pi_ radians apart. Increasing the parameter further causes the fixed points to continue moving along, until they finally meet again and are annihilated in a saddle-node bifurcation, thus signaling the end of the locking interval
