Investigation of environmental and circulating conditions of heavy and persistent rainfall in Dez basin

Variation of rainfall origin in different parts of Iran along with latitude, distance and proximity to moisture sources, etc. causes rainfall behaviors such as intensity and continuity to have temporal and spatial changes .Using statistical methods and discharge data of Dez river, severe floods of this river were extracted to identify the effective factors in their creation.In this research, the information of all effective atmospheric levels has been analyzed using a combination of illustrative and appropriate maps.And Synoptic and thermodynamic properties of heavy cloud precipitation in Dez catchment At the same time, the synoptic patterns lead to the prolongation of the systems on the catchment And its effect on flow rate was identified and presented.The purpose of this study was to identify the pattern or patterns of durable rainfall systems in the Dez River Basin. There is a deep landing in the eastern Mediterranean that has caused the cold European air to fall in the west of the ship, as well as the transfer of moisture from the Arabian Sea and the Persian Gulf in the east. And the conditions for creating an ascent in the Dez River Basin are the most important elements of the pattern of heavy and durable rainfall in this basin. Water resources planning, prevention and timely information, and flood control and control are among the results that can be expected from this research.