(i.e. both <code>threshCriterion</code> and <code>durationCriterion</code> are <code>TRUE</code>),
and a sequential number uniquely identifying the detected event(s). The second list
component (<code>event</code>) will contain the heatwave event metrics. If <code>protoEvents = TRUE</code>
then only the <code>climatology</code> will be reported. Note also that if <code>protoEvents = TRUE</code>
it will ignore whatever the user provides to the <code>categories</code> argument and anything
else passed to <code