Özet:
In this study, the hydrological modelling of Arkun dam basin is made by using GR4J runo -precipitation model and CemaNeige snow accounting routine. Arkun dam located in C oruh River is chosen as an outlet and its basin determined by using Geographical Information Systems. The area is chosen due to its characteristics. The basin is largely fed by melting snow during spring and early summer seasons. In the working area, the highest mountains of Turkey are located. The altitude of Arkun dam is 870 m and the highest altitude of the basin is 3705 m. The elevation uctuates throughout the basin. Due to these characteristics, the hydrology of the basin is mostly a ected by the altitude di erences, snow melting and its delayed e ect. In this study, model parameters of GR4J and CemaNeige are tried to be determined for Arkun dam basin in order to be used in stream ow calculations. Besides, GR4J model is also presented alone without any snow accounting routine. The necessity of a snow accounting routine, in this case CemaNeige, is clearly shown.