make_clusters(S, t)

Extended = {} (i.e., empty set);

while Msh(S) ≠ {}:

mx0y0: = a randomly selected member of Msh(S); Cx0y0 = {mx0y0}

For each mesh mxy in Cx0y0/Extended: #each mesh not extended yet gets extended below

while Msh(S) ∩ surround(mxy) ≠ {}

add_to_cluster = Msh(S) ∩ surround(mxy)

Cx0y0 = Cx0y0 ∪ add_to_cluster

Msh(S) = Msh(S)/add_to_cluster

Extended = Extended + mxy

return

Computing Hrsat (S, t) as the alarm:

if  rank τ in [t-min(T, t-t0), t] Hravr(S, τ = t) $\le$ γ min(T, t-t0) and

(stdev τ in [t-dt, t] Hr(S, τ) $<$ θstd or stdev τ in [t-dt/2, t] Hr(S, τ) $>$ 2 stdev τ in [t-dt, t-dt/2] Hr(S, τ))

Hrsat(S, t) = Hr(S, t)