Human life has always been influenced by the interaction between water an‎d air. So that since long ago, humanity has always benefited from heavenly gifts an‎d used them to advance their livelihood. But the interaction between the atmosphere an‎d the water bodies has not always been in the interest of humans. For example, the occurrence of dangerous floods has always been a threat to mankind. Since climate fluctuations in one region affect another region, the interaction between the atmosphere an‎d the ocean has been the subject of many scientific discussions in recent years. Because from the results of the above-mentioned interaction, we can point out the occurrence of massive floods that have been a very big threat to human life an‎d property. Therefore, researchers have always been trying to find the relationship between the indicators of water areas an‎d precipitation factors in order to discover the trends an‎d models related to precipitation. Today, it has been proven that remote connection patterns prevail in all parts of the earth an‎d even minor changes in one of the factors can cause wide fluctuations in other climates. In the current research, the effects of the Indian Ocean surface temperature index, as a force link index, on the maximum 24-hour rainfall in the southeast of the country were studied. For this purpose, the data defined as the Indian Ocean surface temperature index, which is actually the difference between the values of the western part of this ocean an‎d its southeastern side, was used. Also, Zahedan, Saravan, Zabol, Iranshahr an‎d Chabahar stations were selec‎ted in the southeastern province of the country (Sistan an‎d Baluchistan) to study the response of fluctuations an‎d trends of maximum 24-hour rainfall in these stations to the DMI index of the Indian Ocean. To investigate the relationship between maximum 24-hour rainfall an‎d DMI index, Spearmanʹs correlation method was used, which was fitted between the above values in two annual an‎d monthly scales. The findings indicated the existence of correlation in some years in all stations. In order to understan‎d the behavior of torrential rains in the studied area an‎d to identify their trends, univariate Man-Kendall an‎d multi-variable Man-Kendall methods were also used. The results showed that the annual trend was negative in Zahedan an‎d Zabul station an‎d positive in Chabahar station. Also, in order to check the DMI index on the maximum 24-hour rainfall trend of the region, the partial Mann-Kendall test showed that in some months an‎d years this index was effective on the maximum rainfall trend.

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سعيد سلطاني كوپائي , عليرضا گوهري