  The modeling of risk situations that occur in a space-time framework can be
done using max-stable random fields on lattices. Although the summary
coefficients for the spatial and temporal behaviour do not characterize the
finite-dimensional distributions of the random field, they have the advantage
of being immediate to interpret and easier to estimate. The coefficients that
we propose give us information about the tendency of a random field for local
oscillations of its values in relation to real valued high levels. It is not
the magnitude of the oscillations that is being evaluated, but rather the
greater or lesser number of oscillations, that is, the tendency of the
trajectories to oscillate. We can observe surface trajectories more smooth over
a region according to higher crossinggram value. It takes value in $[0,1]$ and
increases with the concordance of the variables of the random field.
