Other disciplines have moved away from gradualism as theory has shown that
such assumptions are unsustainable. However, climatology has been slow to respond, despite over fifty years having elapsed since the climate system was shown to be stochastic rather than deterministic over interannual to decadal timescales and perhaps longer (e.g., Ghil, 2012). A comprehensive theory of climate variability
remains to be developed (Ghil, 2012).