  In the present paper, the effect of noise intensity on stochastic parabolic
equations is discussed. We focus on the effect of noise on the energy solutions
of the stochastic parabolic equations. By utilising It\^o's formula and the
energy estimate method, we obtain the excitation indices of the energy
solutions $u$ at any finite time $t$. Furthermore, we improve certain existing
results in the literature by presenting a comparably simple method to show
those existing results.
