مدل‏ سازی و پایش پدیده خشک‌سالی در جنوب غرب ایران با استفاده از شاخص جدید فازی

خشک‌سالی یکی از مخاطرات طبیعی و تاثیرگذار در همه فعالیت‏های موجودات زنده است. هدف از پژوهش حاضر مدل‏سازی و تحلیل خشک‌سالی در جنوب ‏غرب ایران است. برای این کار، نخست از پارامترهای اقلیمی‌ بارش، دما، ساعات آفتابی، حداقل رطوبت نسبی، و سرعت باد‌ در بازه زمانی 32‌ ساله (1987-2018) در 15 ایستگاه جنوب ‏غرب ایران استفاده شد. برای مدل‏سازی شاخص فازی t.i.b.i، نخست چهار شاخص (set, spi, seb, mczi) با استفاده از منطق فازی در نرم‏افزار matlab فازی‏سازی شدند. سپس، شاخص‏ها با هم مقایسه شدند و در نهایت از مدل تصمیم‏گیری چندمتغیره saw برای اولویت‌سنجی مناطق درگیر با خشک‌سالی استفاده شد. یافته‏های پژوهش نشان داد بیشترین درصد فراوانی وقوع خشک‌سالی در مقیاس 6 و 12ماهه در ایستگاه اسلام‏آباد غرب و کمترین آن در مقیاس شش‌ماهه در همدان فرودگاه و در مقیاس دوازده‌ماهه در ایستگاه خرم‌آباد رخ داده است. مدل t.i.b.i طبقات خشک‌سالی چهار شاخص یادشده را با سطح اطمینان بالا در خود منعکس کرد. براساس مدل‏سازی انجام‌گرفته، شاخص فازی t.i.b.i نسبت به شاخص فازی spei برتری نسبی نشان داد. در نهایت، براساس مدل تصمیم‏گیری چندمتغیره saw، ایستگاه اسلام‏آباد غرب با مقدار امتیاز 1 در اولویت بیشتر در معرض درگیری خشک‌سالی قرار گرفت.

Modeling and monitoring Drought phenomenon in southwest of Iran Using the new fuzzy index

Extended abstract Introduction Drought is one of the natural hazards, which during its occurrence has damages and effects of irreparable damage in various sectors of agriculture, economics, and so on. In recent years, different regions of the world have experienced more severe drought (Mirzai et al., 2015: 98). Also, drought is one of the most important natural disasters affecting agriculture and water resources, which is abundant especially in arid and semiarid regions (Shamsenya et al., 2008: 165).Drought changes are wellsuited for optimal management of water resources utilization (Alizadeh, 2017: 169). Drought is also referred to as a climate phenomenon with a lack of humidity and rainfall relative to normal conditions. This phenomenon strongly affects all aspects of human activity (Zeinali and Safarian Zangier, 2017). Regarding the studies done inside and outside of the country, this study attempted to model and monitor the drought phenomenon in southwest of Iran using a new index. Material and method In this study, drought modeling in southwest of Iran was carried out using climatic data of rainfall, temperature, sunshine, minimum relative humidity and wind speed monthly (6 and 12 months scale) for the period of 31 years (1987 2018) in five provinces of Khuzestan, Lorestan, Ilam, Kermanshah and Hamedan in 15 stations using a new index modeling called the TIBI Architectural Index, fuzzyized from four indices (SET, SPI, SEB, MCZI) The World Meteorological Organization was used. Fuzzy index T.I.B.I The fuzzy index (T.I.B.I) is presented to resolve some of the disadvantages of the SPEI index. The index T.I.B.I was derived from the integration of the indicators (SET, SPI, SEB, MCZI), which is the result of drought fuzzy modeling architecture that is designed using fuzzy logic in a fuzzy inference system. Conclusion Monitoring of drought fluctuations based on four integrated indicators in T.I.B.I In order to investigate the effect of drought fluctuations in drought conditions of stations, it is possible to find changes in the parameters (SET, SPI, SEB, MCZI) in the TIBI index, Checked. Considering the large number of stations studied, for the sake of better understanding, only the drought series chart, East Islamabad station at two 6 and 12month scale was presented in Figures 7 and 8 (Figures 7 and 8). The abovementioned red dot indicates a 6month drought margin with a value of 0.44 and more, and represents a 0.44 and a magnitude 12month scale. The analysis of these forms shows that at IslamabadWest station at 6 and 12month scale, the temperature was different in the drought environment, which was decreasing in the 6month scale from April 1994 to August 1997, and after This month has been gaining momentum, from July 1996 through 2003, an incremental increase. If the impact of rainfall on a 12month scale is weaker than the 6month scale. Between May 1994 and November 1997, the declining trend followed by a 12monthlong drought after June 1997 to December 2002, followed by a similar pattern. And the indicators (SET, SPI, SEB, MCZI) affect the TIBI index and show some trends, indicating that the new TIBI fuzzy index reflects the four indicators well and the scale Drought classes were presented in Table 5. The T.I.B.I index on a 12month scale shows a sharper shape than scale 6. Results One of the natural hazards that has affected the country in recent years is the dangers of drought. One of these areas affected by drought was the southeastern part of Iran, where researchers conducted many studies to monitor drought in Southwest Iran with different models but did not adequately address the issue. Is The purpose of this study is to model and monitor the drought phenomenon in southwest of Iran using a new fuzzy index in the 6 and 12month scale. In the study area, the intensity and frequency of drought are more than 6 months on a 12month scale. Drought persistence is more than 12 months old. Shortterm droughts were less sustained and affected by rainfall and temperature parameters. While the severity of drought in the long periods of time was less responsive to temperature and precipitation variations.The trend of drought in the southwest of Iran was increasing and the temperature trend was more rapid, increasing and increasing trend. The highest frequency of drought occurrence was at the 6th and 12th month scale, IslamabadWest station and the lowest rate was 6 Hamadan airport scale and 12month scale Khorram Abad station. The percentage of drought frequency in Hamedan Nogheh, Islamabad and Zarapulzahab stations was higher than the 6month scale in the 12month scale.