تحلیل اثر طول دوره آماری بر احتمال وقوع خشکسالی با استفاده از رویکرد توابع مفصل (مطالعه موردی: ایستگاه سینوپتیک اراک)

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی آب، دانشکده کشاورزی و محیط زیست، دانشگاه اراک، اراک ، ایران

2 دانشیار، گروه مهندسی آب، دانشکده کشاورزی و محیط زیست، دانشگاه اراک، اراک، ایران دانشیار، گروه منابع آب پژوهکشده آب، دانشگاه اراک،

3 عضو سازمان هواشناسی استرالیا، ملبورن ، استرالیا

4 گروه هیدرولوژی و منابع آب، دانشکده مهندسی آب و محیط زیست، دانشگاه شهید چمران اهواز، اهواز، ایران

چکیده

در سال­های اخیر با توسعه روش­های آماری و کاربرد ریاضیات پیشرفته ساختار وابستگی موجود در پدیده­های حدی نظیر خشکسالی مورد توجه قرار گرفته است. در مطالعه حاضر تحلیل چندمتغیره خشکسالی­های ایستگاه سینوپتیک اراک با استفاده از شاخص SPEI و توابع مفصل و اثر طول دوره آماری بر احتمال وقوع خشکسالی بررسی گردید. بدین منظور داده­های بارش و دمای مشاهداتی و شبکه­ای پایگاه اقلیمی جهانی (CRU) برای ایستگاه منتخب جمع­آوری و دو دوره آماری 100 و 37 ساله برای این تحقیق انتخاب شده است. سپس خصوصیات مدت و شدت خشکسالی در مقیاس­های زمانی مختلف (1، 3، 6، 9 و 12ماهه) استخراج و ساختار وابستگی موجود در بین مشخصه­ها با استفاده از ضرایب همبستگی اسپیرمن و تاو کندال بررسی و مشخص گردید که بجز در مقیاس یک ماهه، در سایر مقیاس­های زمانی همبستگی معناداری بین مشخصه­ها وجود دارد. پس از تعیین بهترین توزیع حاشیه­ای، پنج تابع مفصل برای ایجاد توزیع دو متغیره شدت و مدت خشکسالی برازش داده شد. نتایج نشان داد که در ایستگاه اراک برای هر دو دوره آماری 100 و 37 ساله به­ترتیب مفصل کلایتون و گامبل- هوگارد به دلیل دارا بودن بیشترین مقدار NS و کمترین مقدار NRMSE بهترین عملکرد را داشته و برای ایجاد توزیع­های دومتغیره شدت و مدت خشکسالی انتخاب شدند. همچنین نتایج حاکی از آن بود که دوره آماری 37 ساله برای برررسی خشکسالی­ها با شرط "یا" مناسب بوده اما در حالت "و" و تشدید خشکسالی­ها، دوره بازگشت توأم نزدیک به 45 سال می­رسد. بنابراین پیشنهاد می­شود که از دوره آماری 100 ساله برای تحلیل خشکسالی­های منطقه مورد مطالعه استفاده شود.

کلیدواژه‌ها


عنوان مقاله [English]

Analysis of the Effect of Statistical Period Length on Occurrence Probability of Drought Using the Copula Functions Approach (Case Study: Arak Synoptic Station)

نویسندگان [English]

  • Kimia Nadari 1
  • Mahnoosh Moghaddasi 2
  • Ashkan Shokri 3
  • Farshad Ahmadi 4
1 Department of Water Science and Engineering, Faculty of Agriculture and Environment, Arak University, Arak, Iran
2 Associate professor, Department of Water Science and Engineering, Faculty of Agriculture and Environment, Arak University, Arak, Iran. 3Associate professor, Department of Water Resources, Water Institute, Arak University, Arak, Iran.
3 Member of Bureau of Meteorology, Australia, Melbourne Australia
4 Department of Hydrology and Water Resources Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran
چکیده [English]

In recent years, with the development of statistical methods and the application of advanced mathematics, the structure of dependence on extreme phenomena such as drought has been considered. In the present study, multivariate analysis of droughts using SPEI and copula functions and the effect of statistical period length on the occurrence probability of drought was investigated in Arak synoptic station. For this purpose, precipitation and observational temperature data and global climate database (CRU) networks have been collected for the selected station, and two statistical periods of 100 and 37 years have been selected for this research. Then, the characteristics of duration and severity of drought were extracted and at different time scales (1, 3, 6, 9, and 12), and its dependency structure was calculated by Spearman’s rho and Kendall’s tau correlation coefficients that it shows there is a significant correlation between severity and duration of drought except on one-month scales. After determining the best fitted marginal distributions on the drought characteristics, the fitness of five different copulas for developing the bivariate distribution of severity and duration of drought was examined. The results showed that at Arak station for both statistical periods of 100 and 37 years, Clayton and Gumble-Huggard copula functions, respectively, due to having the highest value NS (0.9, 0.9) and the lowest values of NRMSE (12.9, 7.9). The results also showed that the 37-year statistical period was suitable for the study of droughts with the condition "or" but in the case of "and" and the intensification of droughts, the joint return period reaches nearly 45 years. Therefore, it is recommended that a statistical period of 100 years be used to analyze the droughts in the study area.

کلیدواژه‌ها [English]

  • Climate Research Unit
  • Marginal distribution
  • Dependency structure drought characteristics
Abdollahi Asadabadi, S., Akhondali, A. M. and Mirabbasi, R. (2018). Frequency analysis of rainfall characteristics using copula functions (Case study: Kasilian Basin). Eco Hydrology, 5(2), 497-509. .(In Farsi)
Abbasian, M. and Abrishamchi, A. (2014). Comparison of multivariate with univariate analysis for drought event using copula functions. In: Proceedings of 9th National Congress of Civil Engineering, Noshirvani University of Babol, Babol, Iran. (In Farsi)
Ahmadi, F., Radmanesh, F. and Mirabbasi, R. (2016). Analysis of rainfall trends in the northern half of the country in the last half century.Water and Soil Science, 26(1), 207-224. (In Farsi)
Ahmadi, F., Radmanesh, F., Parham, Gh. A. and Mirabbasi, R. (2017). Comparison of common and intelligent methods in estimating the detailed function parameter in order to analyze the multivariate frequency of the minimum flow (Case study: Dez catchment).Eco Hydrology, 4(2), 315-329.(In Farsi)
Ahmadi, F., Nazeri Tahroudi, M., Mirabbasi, R., Khalili, K. and Jhajharia, D. (2018). Spatiotemporal trend and abrupt change analysis of temperature in Iran. Meteorological Applications, 25(2), 314-321.
Bazrafshan, O., Zamani, H. and Shekari, M. (2020). A copula‐based index for drought analysis in arid and semi‐arid regions of Iran. Natural Resource Modeling, 33(1), e12237.
Byun, H. R. and Wilhite, D. A. (1999). Objective quantification of drought severity and duration. Journal of Climate, 12(9), 2747-2756.
Das, J., Jha, S. and Goyal, M. K. (2020). Non-stationary and copula-based approach to assess the drought characteristics encompassing climate indices over the Himalayan states in India. Journal of Hydrology, 580, 124356.
Danandeh Mehr, A., Sorman, A. U., Kahya, E. and Hesami Afshar, M. (2020). Climate change impacts on meteorological drought using SPI and SPEI: case study of Ankara, Turkey. Hydrological Sciences Journal, 65(2), 254-268.
Dinpashoh, Y., Mirabbasi, R., Jhajharia, D., Abianeh, H. Z. and Mostafaeipour, A. (2013). Effect of short-term and long-term persistence on identification of temporal trends. Journal of Hydrologic Engineering, 19(3), 617-625.
Eini, M. R., Javadi, S. and Delavar, M. (2018). Evaluating the performance of CRU and NCEP CFSR global reanalysis climate datasets, in hydrological simulation by SWAT model, Case Study: Maharlu basin. Iran-Water Resources Research14(1), 32-44. (In Farsi)
Farrokhnia, A. and Morid, S. (2008). Analysis of drought severity and duration using copula functions. In: Proceedings of 4th National Congress of Civil Engineering, Tehran University, Tehran, Iran. (In Farsi)
Harris, I., Jones, P.D., Osborn T.J. and Lister, D.H.(2013). Updated high-resolution grids of monthly climatic observations - the CRU TS3.10 Dataset. International Journal of Climatology, 34(3), 623-642.
Jahannemaeii, N., Khosravinia,  P., Sanikhani, H. and Mirabbasi, R. (2020). Bivariate Analysis of Duration and Severity of Drought in Sanandaj and Saqez Stations. Irrigation and Water Engineering, 11(42), 131-146. .(In Farsi)
 Joe, H. (1997). Multivariate models and multivariate dependence concepts. CRC Press.
Kempes, C. P., Myers, O. B., Breshears, D. D. and Ebersole, J. J. (2008). Comparing response of Pinus edulis tree-ring growth to five alternate moisture indices using historic meteorological data. Journal of Arid Environments, 72(4), 350-357.
Khajeh, S., Paimozd, S. and Moghaddasi, M. (2017). Assessing the impact of climate changes on hydrological drought based on reservoir performance indices (case study: ZayandehRud River basin, Iran). Water Resources Management, 31(9), 2595-2610.
Khalili, K., Tahoudi, M. N., Mirabbasi, R., & Ahmadi, F. (2016). Investigation of spatial and temporal variability of precipitation in Iran over the last half century. Stochastic environmental research and risk assessment, 30(4), 1205-1221.
Kim, T. W., Valdés, J. B., and Yoo, C. (2003). Nonparametric approach for estimating return periods of droughts in arid regions. Journal of Hydrologic Engineering8(5), 237-246.
Li, L., She, D., Zheng, H., Lin, P. and 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.
Liu, C., Yang, C., Yang, Q. and Wang, J. (2021). Spatiotemporal drought analysis by the standardized precipitation index (SPI) and standardized precipitation evapotranspiration index (SPEI) in Sichuan Province, China. Scientific Reports, 11(1), 1-14.
Mahmoudi, P., Rigi, A. and Kamak, M. M. (2019). Evaluating the sensitivity of precipitation-based drought indices to different lengths of record. Journal of Hydrology, 579, 124181.
McKee, T.B., N.J. Doesken and J. Kleist. 1993. The relationship of drought frequency and duration to time scales. In Proceedings of the 8th Conference on Applied Climatology, 17:179-183.
Mesbahzadeh, T., Mirakbari, M., Mohseni Saravi, M., Soleimani Sardoo, F. and Miglietta, M. M. (2020). Meteorological drought analysis using copula theory and drought indicators under climate change scenarios (RCP). Meteorological Applications, 27(1), e1856.
Moghaddasi, M., Morid, S. and Ghaemi, H. (2005). Daily drought monitoring, Tehran Province. Iranian Journal of Agriculture Science, 26(1), 51-62. (In Farsi)
Mohtashami Borzadaran, H. A. (2013). Distorted copula and its properties. MSc. Thesis, Ferdowsi University Of Mashhad.
Mirakbari, M., A. Ganji and S.R. Fallah. 2010. Regional bivariate frequency analysis of meteorological droughts. Journal of Hydrologic Engineering, 15(12): 985-1000.
Mirabbasi, R., Fakheri-Fard, A. and Dinpashoh, Y. (2012). Bivariate drought frequency analysis using the copula method. Theoretical and Applied Climatology, 108(1), 191-206.
Miri, M., Azizi, G., Khoshakhlagh, F.and Rahimi, M. (2016). Evaluation statistically of temperature and precipitation datasets with observed data in Iran. Iran-Watershed Management Science and, Engineering, 35, 39-51. (In Farsi)
Nazemi A. and Elshorbagy A. (2011). Application of copula modeling to the performance assessment of reconstructed watersheds. Stochastic environmental research and risk assessment, 26(2): 189-205.
Nelsen, R. B. (2006). An Introduction to Copulas. Springer, New York. MR2197664.
Nosrati, K., (2014). Assessment of standardized precipitation evapotranspiration index (SPEI) for drought identification in different climates of Iran. Environmental Science, 12(4), 63-74. (In Farsi)
Pei, Z., Fang, S., Wang, L. and Yang, W. (2020). Comparative analysis of drought indicated by the SPI and SPEI at various timescales in inner Mongolia, China. Water, 12(7), 1925.
Sajeev, A., Deb Barma, S., Mahesha, A. and Shiau, J. T. (2021). Bivariate drought characterization of two contrasting climatic regions in India using copula. Journal of Irrigation and Drainage Engineering, 147(3), 05020005.
Shiau, J. T. (2006). Fitting drought duration and severity with two-dimensional copulas. Water resources management20(5), 795-815.
Shiau, J. T. and Shen, H. W. (2001). Recurrence analysis of hydrologic droughts of differing severity. Journal of Water Resources Planning and Management127(1), 30-40.
Singh, S. K., Chamorro, A., Srinivasan, M. S. and Breuer, L. (2017). A copula-based analysis of severity-duration-frequency of droughts in six climatic regions of New Zealand. Journal of Hydrology (New Zealand)56(1), 13-30.
Sklar, M. (1959). Fonctions de repartition an dimensions et leurs marges. Publ. inst. statist. univ. Paris8, 229-231.
Vicente-Serrano, S. M., Beguería, S. and 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.
Won, J., Choi, J., Lee, O. and Kim, S. (2020). Copula-based joint drought Index using SPI and EDDI and its application to climate change. Science of the Total Environment, 744, 140701.
Yevjevich, V. (1967). An objective approach to definitions and investigations of continental hydrologic droughts. Journal of Meteorology, 36(5), 41-50.
Yue, S. and Rasmussen, P. (2002). Bivariate frequency analysis: discussion of some useful concepts in hydrological application. Hydrological Processes, 16(14), 2881-2898.
Zamani, R., Mirabbasi, R., Nazeri, M., Meshram, S. G. and Ahmadi, F. (2018). Spatio-temporal analysis of daily, seasonal and annual precipitation concentration in Jharkhand State, India. Stochastic environmental research and risk assessment, 32(4), 1085-1097.
Zhang, Q., Chen, Y. D., Chen, X. and Li, J. (2011). Copula-based analysis of hydrological extremes and implications of hydrological behaviors in the Pearl River basin, China. Journal of Hydrologic Engineering, 16(7), 598-607.