  In this Letter we follow the short-ranged Syrian refugees' migration to
Lebanon as documented by the UNHCR. We propose a model inspired by the
Debye-H\"{u}ckel theory and show that it properly predicts the refugees'
mobility while the gravity model fails. We claim that the interaction between
origin cities attenuates and/or extenuates the flux to destinations, and
consequently, in analogy with the effective charges of interacting particles in
a plasma, these source cities are characterized by effective populations
determined by their pairwise remoteness/closeness and defined by areas of
control between the fighting parties.
