بررسی انواع خشکسالی و مشخصه‌های آن در ایران با استفاده از شاخص بارش تبخیر-تعرق استاندارد شده (SPEI)

نوع مقاله : مقالات پژوهشی

نویسندگان

• نسترن ترابی نژاد ¹
• آذر زرین ²
• عباسعلی داداشی رودباری ³

¹ دانشجوی کارشناسی ارشد اقلیم شناسی، گروه جغرافیا، دانشگاه فردوسی مشهد

² دانشیار اقلیم شناسی، گروه جغرافیا، دانشگاه فردوسی مشهد

³ پژوهشگر پسادکتری اقلیم شناسی، گروه جغرافیا، دانشگاه فردوسی مشهد

https://doi.org/10.22067/jsw.2023.81322.1257

چکیده

خشکسالی یک مخاطره طبیعی پرهزینه با پیامدهای گسترده بر کشاورزی، اکوسیستم و منابع آب است. هدف از این پژوهش بررسی مشخصه­های خشکسالی و انواع آن در ایران طی چهار دهه گذشته است. برای این منظور از داده­های 49 ایستگاه هواشناسی همدید طی دوره آماری 2020-1981 استفاده شده است. خشکسالی با شاخص بارش تبخیر-تعرق استاندارد شده (SPEI) در چهار مقیاس 3، 6، 12 و 24 ماهه مورد بررسی قرار گرفته است. سپس با استفاده از تئوری Run مشخصه­های خشکسالی شامل بزرگی، طول دوره، شدت و فراوانی آن برای هر چهار مقیاس مورد بررسی محاسبه شد. نتایج نشان داد که در دوره چهل ساله مورد بررسی فراوانی رخداد خشکسالی از حداقل 13/12 درصد تا حداکثر 13/18 درصد از کل ماه­ها در مناطق مختلف کشور در نوسان است. بررسی اقلیم­شناسی مشخصه­های خشکسالی در پهنه ایران نشان می­دهد که فراوانی خشکسالی در غرب، جنوب­غرب، سواحل خلیج فارس و شمال­غرب ایران بیش­تر از سایر مناطق کشور است. این در حالی است که طول دوره خشکسالی در مناطق شرقی و مرکزی ایران بالاتر است. بررسی انواع خشکسالی نشان می­دهد که بیش از 60 درصد از خشکسالی­های رخ داده در ایران از نوع خشکسالی متوسط است. خشکسالی­های متوسط و شدید در ایران بیش­تر در غرب، جنوب­غرب و شمال­غرب ایران دیده می­شوند. طول دوره خشکسالی ایران از حداقل 3 ماه برای SPEI-3 تا بیش از 8 ماه برای SPEI-24 در تغییر است. شدت خشکسالی نیز در مناطق شرقی و داخلی بیش­تر از مناطق غربی و شمال­غربی ایران است. تغییرات دهه­ای خشکسالی نیز نشان می­دهد که طی دهه­های اخیر طول دوره و بزرگی خشکسالی در ایران افزایش یافته و شدت خشکسالی کاهش داشته است.

کلیدواژه‌ها

• انواع خشکسالی
• تئوری RUN
• خشکسالی
• مشخصه‌های خشکسالی
• ایران

20.1001.1.20084757.1402.37.3.9.2

موضوعات

• هواشناسی کشاورزی

عنوان مقاله [English]

Analysis of Different Types of Droughts and Their Characteristics in Iran Using the Standardized Precipitation Evapotranspiration Index (SPEI)

نویسندگان [English]

• N. Torabinezhad ¹
• A. Zarrin ²
• A.A. Dadashi-Roudbari ³

¹ Graduate student of Climatology, Department of Geography, Ferdowsi University of Mashhad

² Associate Professor of Climatology, Department of Geography, Ferdowsi University of Mashhad

³ Postdoctoral Research Associate of Climatology, Department of Geography, Ferdowsi University of Mashhad

چکیده [English]

Introduction
Drought is a costly natural hazard with wide-ranging consequences for agriculture, ecosystems, and water resources. The purpose of this research is to determine the characteristics of drought and its types in Iran during the last four decades. Drought turns into different types in the water cycle and imposes many negative consequences on natural ecosystems and different socio-economic sectors. According to International Disaster Database (EM-DAT), drought accounts for 59% of the economic losses caused by climate change. Many parts of the world have experienced extensive and severe droughts in recent decades. In Iran, droughts have occurred frequently during the last four decades and have become more severe in the last decade.
Materials and Methods
In this research, we used precipitation, temperature, wind speed, and sunshine hours of 49 synoptic meteorological stations during 1981-2020. Drought has been investigated with The Standardized Precipitation-Evapotranspiration Index (SPEI) in four scales of 3, 6, 12, and 24 months, which represent meteorological, agricultural, hydrological, and socio-economic droughts. To calculate the SPEI, the precipitation variable (P) is analyzed with the cumulative difference between P and potential evapotranspiration (PET). In other words, surplus/deficit climate water balance (CWB) is considered. The FAO Penman-Monteith method was used to calculate PET. Then, using the RUN theory, the characteristics of drought, including its magnitude, duration, intensity, and frequency, were determined for all four investigated scales.
Results and Discussion
The results showed that the frequency of drought events fluctuates from a minimum of 12.13% to a maximum of 18.13% in different regions of the country during 1981-2020. The climatological study of drought characteristics shows that the most frequent drought events occurred in the west, southwest, and southern coasts of the Persian Gulf and northwest of Iran compare to other regions of the country. This is while the duration of the drought period is longer in the eastern and interior regions of Iran. Examining the types of droughts shows that more than 60% of the droughts occurring in Iran are moderate droughts. Moderate and severe droughts are mostly seen in the west, southwest, and northwest of Iran. The duration of Iran's drought varies from at least 3 months in meteorological drought to more than 8 months in socio-economic drought. Therefore, droughts are more frequent in the western regions and longer in the eastern regions. The intensity of drought is also higher in the eastern and interior regions than in the western and northwestern regions of Iran. The decadal changes of drought show that the duration and magnitude of drought in Iran have increased and the severity of the drought has decreased during recent decades.
Conclusion
The intensity, magnitude, and duration of the drought period in Iran increased with the increase of the investigated scales from 3 months to 24 months. Examining the average frequency of drought showed that as we move from meteorological drought to socio-economic drought, the frequency of drought increases, which confirms the previous findings. The eastern and southeastern parts of Iran have experienced a longer duration and larger magnitude of drought than the western and northwestern Iran, which can be caused by the climate conditions of this region, i.e., high temperature and evapotranspiration and less precipitation, and seasonality.
The maximum magnitude of drought in Iran is related to socio-economic drought (SPEI-24) followed by hydrological drought (SPEI-12). This characteristic has increased especially in the last two decades (2001-2020) compared to the previous decades (1981-2000). This is while the magnitude of meteorological (SPEI-3) and agricultural (SPEI-12) droughts do not increase much in the last two decades compared to the previous decades.
Anthropogenic activities play a more prominent role in increasing the magnitude of socio-economic (SPEI-24) and hydrological (SPEI-12) droughts than natural forcing. With the construction of many dams and the digging of countless deep wells, as well as changing the direction of rivers, the water cycle has been completely affected by human activities during the last four decades in Iran. Obviously, anthropogenic activities play an important role in increasing the magnitude of hydrological and socio-economic droughts. In contrast, meteorological and agricultural droughts have not shown many changes in Iran.
The results of the decadal average of drought intensity showed that this characteristic of drought in the last decade (2011-2020) has decreased compared to previous decades (1981-2010). On the other hand, as mentioned earlier, the magnitude and duration of drought, especially for hydrological and socio-economic droughts, have increased in the last two decades (2001-2020). Therefore, the reason for the decrease in the severity of the drought has a statistical explanation before it has a climatic reason because the severity of the drought is calculated by dividing the magnitude of the drought by its duration.

کلیدواژه‌ها [English]

• Characteristics of drought
• Drought
• Iran
• RUN theory
• Types of droughts

مراجع

1.  

   1. Bachmair, S., Stahl, K., Collins, K., Hannaford, J., Acreman, M., Svoboda, M., ... & Overton, I. C. (2016). Drought indicators revisited: the need for a wider consideration of environment and society. Wiley Interdisciplinary Reviews: Water, 3(4), 516-536. http://dx.doi.org/10.1002/wat2.1154
   2. Bazrafshan, J. (2017). Effect of air temperature on historical trend of long-term droughts in different climates of Iran. Water Resources Management, 31, 4683-4698. https://doi.org/10.1007/s11269-017-1773-8
   3. Brito, S.S.B., Cunha, A.P.M., Cunningham, C.C., Alvalá, R.C., Marengo, J.A., & Carvalho, M.A. (2018). Frequency, duration and severity of drought in the Semiarid Northeast Brazil region. International Journal of Climatology, 38(2), 517-529. https://doi.org/10.1002/joc.5225
   4. Cook, B.I., Mankin, J.S., Marvel, K., Williams, A.P., Smerdon, J.E., & Anchukaitis, K.J. (2020). Twenty‐first century drought projections in the CMIP6 forcing scenarios. Earth's Future, 8(6), e2019EF001461. https://doi.org/ 10.1029/2019EF001461
   5. EM-DAT, (2021). The International Disaster Database. (Available at: https://www.emdat.be/index.php)
   6. Ghabaei, S.M., Zare Abyaneh, H., Mosaedi, A., & Samadi, S.Z. (2016). Assessment of humidity conditions and trends based on standardized precipitation evapotranspiration index (SEPI) over different climatic regions of Iran. Water and Soil, 30(5), 1700-1717. (In Persian with English abstract). http://doi.org/10.22067/jsw.v0i0.47565
   7. Gumus, V., Dinsever, L.D., & Avsaroglu, Y. (2023). Analysis of drought characteristics and trends during 1965–2020 in the Tigris River basin, Turkey. Theoretical and Applied Climatology, 1-17. https://doi.org/10.1007/s00704-023-04363-x
   8. Hao, Z., & AghaKouchak, A. (2013). Multivariate standardized drought index: a parametric multi-index model. Advances in Water Resources, 57, 12-18. https://doi.org/10.1016/j.advwatres.2013.03.009
   9. Heudorfer, B., & Stahl, K. (2017). Comparison of different threshold level methods for drought propagation analysis in Germany. Hydrology Research, 48(5), 1311-1326. https://doi.org/10.2166/nh.2016.258
   10. Isfahani, P.M., Soltani, S., & Modarres, R. (2022). Assessing agrometeorological drought trends in Iran during 1985–2018. Theoretical and Applied Climatology, 150(1-2), 251-262. https://doi.org/10.1007/s00704-022-04159-5.
   11. Kazemzadeh, M., Noori, Z., Alipour, H., Jamali, S., Akbari, J., Ghorbanian, A., & Duan, Z. (2022). Detecting drought events over Iran during 1983–2017 using satellite and ground-based precipitation observations. Atmospheric Research, 269, 106052. https://doi.org/10.1016/j.atmosres.2022.106052.
   12. Li, L., She, D., Zheng, H., Lin, P., & Yang, Z.L. (2020). Elucidating diverse drought characteristics from two meteorological drought indices (SPI and SPEI) in China. Journal of Hydrometeorology, 21(7), 1513-1530. https://doi.org/10.1175/JHM-D-19-0290.1
   13. Li, Y., Qin, Y., & Rong, P. (2022). Evolution of potential evapotranspiration and its sensitivity to climate change based on the Thornthwaite, Hargreaves, and Penman–Monteith equation in environmental sensitive areas of China. Atmospheric Research, 273, 106178. https://doi.org/10.1016/j.atmosres.2022.106178
   14. Lloyd‐Hughes, B., & Saunders, M.A. (2002). A drought climatology for Europe. International Journal of Climatology: A Journal of the Royal Meteorological Society, 22(13), 1571-1592. https://doi.org/10.1002/joc.846
   15. McKee, T.B., Doesken, N.J., & Kleist, J. (1993, January). The relationship of drought frequency and duration to time scales. In Proceedings of the 8th Conference on Applied Climatology, 17(22), 179-183.
   16. Mehta, D., & Yadav, S.M. (2022). Temporal analysis of rainfall and drought characteristics over Jalore District of SW Rajasthan. Water Practice and Technology, 17(1), 254-267. https://doi.org/10.2166/wpt.2021.114
   17. Mianabadi, A., Salari, K., & Pourmohamad, Y. (2022). Drought monitoring using the long-term CHIRPS precipitation over Southeastern Iran. Applied Water Science, 12(8), 183. https://doi.org/10.1007/s13201-022-01705-4
   18. Mosaedi, A., Mohammadi Moghaddam, S., & Kavakebi, Gh. (2017). Drought characteristics based on Reconnaissance Drought Index and its variations in different time periods and regions of Iran. Journal of Water and Soil Conservation, 23(6), 27-52. (In Persian with English abstract). http://doi.org/10.22069/jwfst.2017.8878.2266
   19. Nouri, M., & Homaee, M. (2020). Drought trend, frequency and extremity across a wide range of climates over Iran. Meteorological Applications, 27(2), e1899. https://doi.org/10.1002/met.1899
   20. Palmer, W.C. (1965). Meteorological drought (Vol. 30). US Department of Commerce, Weather Bureau.
   21. Pei, Z., Fang, S., Wang, L., & Yang, W. (2020). Comparative analysis of drought indicated by the SPI and SPEI at various timescales in inner Mongolia, China. Water, 12(7), 1925. https://doi.org/10.3390/w12071925
   22. Peña-Gallardo, M., Vicente-Serrano, S.M., Hannaford, J., Lorenzo-Lacruz, J., Svoboda, M., Domínguez-Castro, F., & El Kenawy, A. (2019). Complex influences of meteorological drought time-scales on hydrological droughts in natural basins of the contiguous Unites States. Journal of Hydrology, 568, 611-625. https://doi.org/10.1016/j.jhydrol.2018.11.026
   23. Pokhrel, Y., Felfelani, F., Satoh, Y., Boulange, J., Burek, P., Gädeke, A., & Wada, Y. (2021). Global terrestrial water storage and drought severity under climate change. Nature Climate Change, 11(3), 226-233. https://doi.org/10.1038/ s41558-020-00972-w
   24. Pour, S.H., Abd Wahab, A.K., Shahid, S., & Ismail, Z.B. (2020). Changes in reference evapotranspiration and its driving factors in peninsular Malaysia. Atmospheric Research, 246, 105096. https://doi.org/10.1016/j.atmosres. 2020.105096
   25. Shi, M., Yuan, Z., Shi, X., Li, M., Chen, F., & Li, Y. (2022). Drought assessment of terrestrial ecosystems in the Yangtze River Basin, China. Journal of Cleaner Production, 362, 132234. https://doi.org/10.1016/j.jclepro.2022. 132234
   26. Sobhani, B., Zengir, V.S., & Kianian, M.K. (2019). Drought monitoring in the Lake Urmia basin in Iran. Arabian Journal of Geosciences, 12, 1-15. https://doi.org/10.1007/s12517-019-4571-1
   27. Svoboda, M., Hayes, M., & Wood, D. (2012). Standardized precipitation index: user guide.
   28. Ullah, I., Ma, X., Yin, J., Saleem, F., Syed, S., Omer, A., & Arshad, M. (2022). Observed changes in seasonal drought characteristics and their possible potential drivers over Pakistan. International Journal of Climatology, 42(3), 1576-1596. https://doi.org/10.1002/joc.7321
   29. Vicente-Serrano, S.M., Beguería, S., & López-Moreno, J.I. (2010). A multiscalar drought index sensitive to global warming: the standardized precipitation evapotranspiration index. Journal of Climate, 23(7), 1696-1718. https://doi.org/10.1175/2009JCLI2909.1
   30. Wang, L., Yuan, X., Xie, Z., Wu, P., & Li, Y. (2016). Increasing flash droughts over China during the recent global warming hiatus. Scientific Reports, 6(1), 30571. https://doi.org/10.1038/srep30571
   31. Wu, B., Ma, Z., & Yan, N. (2020). Agricultural drought mitigating indices derived from the changes in drought characteristics. Remote Sensing of Environment, 244, 111813. https://doi.org/10.1016/j.rse.2020.111813
   32. Xu, K., Yang, D., Yang, H., Li, Z., Qin, Y., & Shen, Y. (2015). Spatio-temporal variation of drought in China during 1961–2012: A climatic perspective. Journal of Hydrology, 526, 253-264. https://doi.org/10.1016/j.jhydrol. 2014.09.047
   33. Yevjevich, V.M. (1967). Objective approach to definitions and investigations of continental hydrologic droughts, An (Doctoral dissertation, Colorado State University. Libraries).
   34. Zarei, A.R. (2019). Analysis of changes trend in spatial and temporal pattern of drought over south of Iran using standardized precipitation index (SPI). SN Applied Sciences, 1, 1-14. https://doi.org/10.1007/s42452-019-0498-0
   35. Zhao, R., Sun, H., Xing, L., Li, R., & Li, M. (2023). Effects of anthropogenic climate change on the drought characteristics in China: From frequency, duration, intensity, and affected area. Journal of Hydrology, 617, 129008. https://doi.org/10.1016/j.jhydrol.2022.129008
   36. Zhuang, X., Hao, Z., Singh, V. P., Zhang, Y., Feng, S., Xu, Y., & Hao, F. (2022). Drought propagation under global warming: Characteristics, approaches, processes, and controlling factors. Science of The Total Environment https://doi.org/10.1016/j.scitotenv.2022.156021
   37. Zolina, O., Simmer, C., Kapala, A., & Gulev, S. (2005). On the robustness of the estimates of centennial‐scale variability in heavy precipitation from station data over Europe. Geophysical Research Letters, 32, 1-5. https://doi.org/10.1029/2005GL023231