ablgha: Absorption Land (gha)
Variable
World3 03 indicators sector
Absorption Land (gha) [Ghectares]
ablgha = ppgr * hpup / hpgha

ablgha in the updating graph: ( how to read )
In nodes
hpgha : ha per Gha
hpup : ha per unit of pollution
ppgr : persistent pollution generation rate
Out nodes
hef : Human Ecological Footprint