List of Articles SPEI

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  1 - Monitoring and Zoning of Drought in Southern Alborz
  Porya Ghasemi Masoud Karbasi Alireza Zamani Nouri Mahdi Sarai Tabrizi
  Drought is one of the most important natural hazards and often affects the lives of many people and causes economic damage, environmental damage and social problems. This study was conducted to evaluate the drought trend, intensity and duration during 1988-2019 in relat More

  Drought is one of the most important natural hazards and often affects the lives of many people and causes economic damage, environmental damage and social problems. This study was conducted to evaluate the drought trend, intensity and duration during 1988-2019 in relation to the existing climates in the southern Alborz region. To describe droughts in 3, 6, 12 and 24-month time scales, two drought indices, namely standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) were used. In the case of SPEI, evapotranspiration was an important factor in monitoring drought. Therefore, (HS) method was used to calculate evapotranspiration. Drought intensity and duration maps were presented for SPI and SPEI. The correlation between SPI and SPEI was also examined. In the present results, unlike humid climates, SPI does not have a good correlation with SPEI in extremely arid and arid climates and shows the importance of reference evapotranspiration (ET0) to identify drought in these areas and the index (SPEI) has more accurate monitoring results. Relative to the index (SPI). In addition, drought intensity maps for (SPI) and (SPEI) have shown that the region is experiencing very dry conditions and water resources are affected by intense drought in the short and medium term. Short-term drought in the east of the region (Zanjan) and long-term drought in the center and west of the region (Garmsar, Semnan, Karaj, Tehran) have been more. Manuscript profile
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  2 - Seasonal monitoring of drought in the country Using CRU network data
  Azadeh Arbaby
  Drought is a natural and recurring feature of the climate that occurs in all climatic regions, but its structure and important effects vary from region to region.The main purpose of this study is to investigate the country's meteorological droughts over a long period of More

  Drought is a natural and recurring feature of the climate that occurs in all climatic regions, but its structure and important effects vary from region to region.The main purpose of this study is to investigate the country's meteorological droughts over a long period of time using network data with appropriate spatial and temporal resolution. Data analysis was performed using SPEI multivariate index. The results of drought calculation showed that in terms of time during the period (1966-2015) the rainfall of the cold period of the year decreases in general, the decrease in rainfall in different parts of the country mainly starts from the late 90s In the last years of the study period, except in autumn, we see more repetition of dry periods and unlike the late 80s, droughts have occurred more. Moderate drought intensities are significant and experience of severe droughts, which are among the most critical areas of the country. Manuscript profile