In dynamical systems with periodic attractors which have just emerged
from a saddle-node bifurcation the addition of weak noise may induce c
haotic behaviour. This is accompanied by two remarkable observable eff
ects: noise-induced attractor explosion and noise-induced intermittenc
y. The theory of quasipotentials is used to explain qualitative and un
iversal aspects of these phenomena. The influence of the noise-distrib
ution and its observational implications are discussed.