  We review some recent methods of subgrid-scale parameterization used in the
context of climate modeling. These methods are developed to take into account
(subgrid) processes playing an important role in the correct representation of
the atmospheric and climate variability. We illustrate these methods on a
simple stochastic triad system relevant for the atmospheric and climate
dynamics, and we show in particular that the stability properties of the
underlying dynamics of the subgrid processes has a considerable impact on their
performances.
