So-called environmentally induced migration is multi-level problem. According to Essam El-Hinnawi definition form 1985 environmental refugees as ―those people who have been forced to leave their traditional habitat, temporarily or permanently, because of a marked environmental disruption (natural or triggered by people) that jeopardised their existence and/or seriously affected the quality of their life. The fundamental distinction between `environmental migrants` and `environmental refugees` is a standpoint of contemporsry studies in EDPs.

According to Bogumil Terminski it seems reasonable to distinguish the general category of environmental migrants from the more specific (subordinate to it) category of environmental refugees.

Environmental migrants, therefore, are persons making a short-lived, cyclical, or longerterm change of residence, of a voluntary or forced character, due to specific environmental factors. Environmental refugees form a specific type of environmental migrant.

Environmental refugees, therefore, are persons compelled to spontaneous, short-lived, cyclical, or longer-term changes of residence due to sudden or gradually worsening changes in environmental factors important to their living, which may be of either a short-term or an irreversible character