A Comparative Analysis of the Lake Urmia and the Lake Van Water Level Time Series

Recent decline in the Urmia Lake (LU) level makes it crucial to consider thE issue more than any time before. For this, a comparison of the lake level with the Van Lake water level that is close enough to the LU and benefits from relatively similar climatic conditions can be an effective approach. This topic forms the objective of this research work, in which the trend, regime shift and coherency analyses are implemented. The results indicated a negative trend in the Urmia Lake level, while the vice versa occurred in case of the lake Van. Coherency analysis indicated similarities in annual and inter-annual frequencies of the two lake levels to be 1.3 to 12 years. However, in the case of short term periods, namely less than 4 months, the relations are associated with laggings behind and transpositions.