Suppose that you have a fight with your partner.
It can last 5 min and be solved or it can last, hours, days, weeks, months or even years.
Duration combined with intensity tell you about that shadow's impact.
A 5 min conflict is very different than a 5 year court case battle.
You get that, right?
You can as well have a 5 min shadow explosion at 100% intensity that gets someone killed.
This one would be short life span but high intensity.
That's possible too!
You can have ongoing low intensity shadows like air pollution for instance.
It is bearable, relatively low intensity but has huge impact because of its permanence.
So we have shadow intensity and duration as 2 core parameters that give us shadow impact.
Are there other parameters?