sayad asghari

One of the most important natural hazards that is affecting a large number of people, due to extensive damage, is drought. Drought is also a phenomenon directly related to the issue of water scarcity and because of its reversibility, it can affect the various aspects of human life and the environment. The drought affects almost all the determinants of the hydrological cycle from the onset of precipitation and then the surface water flow and eventually storage in groundwater. Therefore, in this research, due to the results of the stable process of precipitation and temperature in the Ardabil DareRood basin, SPI Index which relies on precipitation, with the RDI index which combines the parameters of potential evapotranspiration and precipitation, were compared and evaluated in different time intervals.

In this study, in order to identify drought and wet periods, it was used from monthly precipitation data, Minimum and maximum monthly temperature for seven synoptic stations, for a 30 years (1985-2014) in the Ardabil DareRood basin in the northwest of Iran. In order to identify the trend in the precipitation and temperature series in this research was used Man-Kendall (MK) and Sen's slope (Sen) models. Also, to assess the long-term stability of the trend in the time series was used the LOWESS curve (at a significant level of 5%). Also using Aridity index, four stations in the arid area and three stations in the semi-arid region were established. In order to calculate the RDI index, the values of potential evapotranspiration were use. The amount of PET in the RDI index using monthly temperature values, and was obtained by the Hargreaves method. Finally, SPI and RDI indices were compared in 3, 6, 9, and 12-month scales.

The results of the LOWESS curve showed that the annual temperature at all stations follows an incremental scenario. While the precipitation behaves differently and often is decreasing. The results also showed that SPI and RDI indices are very similar in different time scales, and R2 is in most cases greater than 0.90. The extreme drought the observed in SPI and RDI models is related to the Ardabil station in 2010-2011 on a 3-month scale, whose values were respectively -3/11 and -3/09. Also, the results showed that the RDI index that Extreme and severe wet values it’s larger than SPI. Eventually, both indices are many similarities with each other but because of RDI's use of PET, It can be used more widely for arid and semi-arid regions of Iran

this research, two SPI and RDI indices were used to compare the drought events in the DarehRood Ardabil basin of the northwest of Iran.Due to the dry and semi-arid climate of most regions of Iran, It is very probable that the amount of precipitation is zero in some seasons. Therefore precipitation-based indices such as SPI may have less efficiency than RDI index, which, in addition to rainfall, uses potential evapotranspiration (PET) in their formulation. Considering the importance of PET parameter in agriculture and water resources management in Iran, It is necessary to examine the RDI index in other regions of Iran, such as the northwest and mountainous regions of Iran and its results can be compared with other indicators such as the important and highly applicable SPI indicator.

The aim of this study is to identify and evaluate the (prioritization) of geopolitical factors (fixed and variable), codes and genomes of Turkey in the formulation of defense policy perspective of the Islamic Republic of Iran. Therefore, it is an applied research of the descriptive depth research type. The statistical population consists of military academic lecturers and experts familiar with the matter comprising two groups of 10 interviewees and 59 questionnaire repliers selected in stratified random sampling method. In this way, the data gathering tools are interviews, researcher-made questionnaires and library studies. The qualitative data was analyzed via content analysis and the hypotheses were tested through descriptive statistics (average coefficient) and inferential statistics (paired comparison and Friedman ranking). The findings suggest the identification of 77 geopolitical factors, codes and genome of Turkey, coded to 34, influencing the formulation of defense policy perspective of the Islamic Republic of Iran. These factors include 9 fixed factors, 5 variable factors and 20 geopolitical codes and genomes which, in order of importance, are: membership of Turkey in NATO and the deployment of missile shield in Turkey, the US-Turkey relations, the political structure of power, foreign policy, the proxy role of Turkey and its relations with Israel. In addition, it was discovered that the geopolitical codes and genomes of Turkey have a significantly greater role and influence in the formulation of defense policy perspective of the Islamic Republic of Iran than the fixed and variable geopolitical factors.