For a wide class of near-integrable systems with additive or multiplic
ative noise the mean zero upcrossing rate for the stochastic system's
Melnikov process tau(u)(-1), provides an upper bound for the system's
mean exit rate, tau(e)(-1). Comparisons between tau(u)(-1) and tau e(-
1) show that in the particular case of additive white noise this upper
bound is weak. For systems excited by processes with tail-limited dis
tributions, the stochastic Melnikov approach yields a simple criterion
guaranteeing the nonoccurrence of chaos. This is illustrated for the
case of excitation by square-wave, coin-toss dichotomous noise. Finall
y, we briefly review applications of the stochastic Melnikov approach
to a study of the behavior of wind-induced fluctuating currents over a
corrugated ocean floor; -the snap-trough of buckled columns with cont
inuous mass distribution and distributed random loading; and open-loop
control of stochastically excited multistable systems.