بررسی تغییرات مقادیر حدی دما و بارش ایران در 60 سال گذشته

نوع مقاله : مقاله پژوهشی

نویسندگان

1 کارشناس ارشد پژوهشی، پژوهشکده اقلیم شناسی مشهد

2 عضو هیات علمی پژوهشکده اقلیم شناسی مشهد

3 عضو هیات علمی، پژوهشکده اقلیم شناسی، مشهد، ایران

چکیده

گرمایش جهانی، باعث احتمال بیشتر رخداد دماهـای حـدی مـی شـود کـه تـأثیرات اجتماعی و زیست- محیطی آنها در مقیاس محلی زیاد است. بیشتر مطالعات انجام شـده در این زمینه، حاکی از کاهش دماهای حدی پایین و افزایش دماهـای حـدی بالاسـت. بـه منظور بررسی این تغییرات ، از داده های دما و بارش روزانه 27 ایستگاه همدیدی (سینوپتیک) کشـور استفاده گردید. نمایهها ی حدی دما نیز در پنج دسته، شامل نمایه ها ی حدی مبتنی بر صدک ،ها مطلق، آستانه ای، دورهای و سایر در دوره 2017-1958 محاسبه گردیـد. نمایه های حدی دما ﻣﺮﺑﻮط ﺑـﻪ ﺑـﺎرش و دﻣـﺎ ﻛـه توسط گروه کارشناسیETCCDMI معرفی شده، استفاده و با نرم افزار RClimdex مقادیر نمایه ها محاسبه شد. به کمک آزمون ناپارامتری من کندال معنا داری روند بر روی هر کدام از ایستگاهها در سطح اطمینان 95 و 90 درصد مورد آزمون قرار گرفت و به کمک رگرسیون خطی و شیب سن مقادیر شیب و نرخ تغییرات بدست آمد. یافته های این پژوهش نشان داد که به طورکلی شاخص های حدی بارش کشور فاقد روند بوده و شاخص های حدی گرم مانند روزهای تابستانی، تعداد شب های حاره ای، روزها و شب های گرم کشور دارای روند افزایشی می باشند. در حالیکه شاخص های حدی سرد در دوره مورد مطالعه روند کاهشی دارند که نشان دهنده کاهش شدت و فراوانی رویدادها و روزها و شبهای سرد است. در ایران هیچ روند زمانی معنی داری در میانگین فراوانی روزهای یخی وجود ندارد. ولی روزهای یخبندان روند کاهشی معنی داری را تجربه کرده است.

کلیدواژه‌ها


عنوان مقاله [English]

Investigation of changes in the extreme of temperature and precipitation in Iran in the last 60 years

نویسندگان [English]

  • sharareh malboosi 1
  • fatemeh abbasi 1
  • Morteza Pakdaman 2
  • zohreh javanshiri 3
1 Climatology Research Institute-Climatic Disasters Group-Mashhad-Iran
2 Assistant Professor, Climatological Research Institute (CRI), Mashhad, Iran
3 climatoligical research institute. Assistant Researcher, Mashhad, Iran
چکیده [English]

Introduction:

Over the past hundred years, human activity has significantly altered the atmosphere and increase of concentration of greenhouse gases lead to warm the earth's surface. This global warming leads to change of climatic extreme index and increases the intensity and frequency of occurrence of extreme climate events. Investigation of extreme values for planning and policy for the agricultural sector and water resource management is important.In this study, a comprehensive review of extreme indices of temperature and precipitation are discussed. This paper aims to investigate extreme temperature and precipitation indices defined in accordance with CCL, and the study of other climatic parameters in Iran.

Materials and Methods:

In this research, statistics and data of 27 stations in the Iran during the period 1958-2017 were used. To evaluate the extreme climate indices trend, 27 indices of rainfall and temperature, were defined by the ETCCDMI. They were calculated by RClimdex software. In this software, prior to the index calculation, data by quality control software became quantitative and incorrect data were controlled and outlier data were examined. The indices were calculated by daily data. 11 rainfall and 16 temperature indices were calculated by this software.The target of the ETCCDMI process is to delineate a standardized set of indices allowing for comparison across regions. These extreme indices were classified in five categories which included the percentile-based extreme indices, the absolute extreme indices, the threshold extreme indices, the periodic extreme indices, and the other indices. They were estimated at the 0.05 significant levels. The Mann-Kendall test was used to investigate the climatic parameters, temperature and precipitation.

Results and Discussion:

Thermal analysis results are consistent with warming patterns, and they have showed that hot extremes indices have increased. Hot days index (SU25), shows a significant positive trend in all studied stations. Number of tropical nights has a positive trend in all stations. Hot day frequency (TX90P) and hot night frequency (TN90P) in most of stations show a positive trend, indicating an increase in the number of warm days and nights. Cold extreme indices show a decreasing trend. (TX10P) and (TN10P) show significant negative trends in all stations and indicate a decrease in cold days and nights. Number of frost day index shows a decreasing trend. Overall, the results revealed a decrease in the severity and frequency of cold events, while warm events during the study period were significantly increased. Comparison of years with the highest rainfall and those with the lowest, showed that the amplitude of fluctuations in precipitation in different years is very high and the distribution of rainfall at distinct stations is different.

Conclusion :

The results showed that intense warm indices, such as the summer day index, the number of tropical regions Warm nights, days, and nights have increased, while during the study period, severe cold indices have decreased. Trends, which show a decrease in the intensity and frequency of cold events. the door There was no significant trend in rainfall indices during the study period.



Introduction:

Over the past hundred years, human activity has significantly altered the atmosphere and increase of concentration of greenhouse gases lead to warm the earth's surface. This global warming leads to change of climatic extreme index and increases the intensity and frequency of occurrence of extreme climate events. Investigation of extreme values for planning and policy for the agricultural sector and water resource management is important.In this study, a comprehensive review of extreme indices of temperature and precipitation are discussed. This paper aims to investigate extreme temperature and precipitation indices defined in accordance with CCL, and the study of other climatic parameters in Iran.

Materials and Methods:

In this research, statistics and data of 27 stations in the Iran during the period 1958-2017 were used. To evaluate the extreme climate indices trend, 27 indices of rainfall and temperature, were defined by the ETCCDMI. They were calculated by RClimdex software. In this software, prior to the index calculation, data by quality control software became quantitative and incorrect data were controlled and outlier data were examined. The indices were calculated by daily data. 11 rainfall and 16 temperature indices were calculated by this software.The target of the ETCCDMI process is to delineate a standardized set of indices allowing for comparison across regions. These extreme indices were classified in five categories which included the percentile-based extreme indices, the absolute extreme indices, the threshold extreme indices, the periodic extreme indices, and the other indices. They were estimated at the 0.05 significant levels. The Mann-Kendall test was used to investigate the climatic parameters, temperature and precipitation.

Results and Discussion:

Thermal analysis results are consistent with warming patterns, and they have showed that hot extremes indices have increased. Hot days index (SU25), shows a significant positive trend in all studied stations. Number of tropical nights has a positive trend in all stations. Hot day frequency (TX90P) and hot night frequency (TN90P) in most of stations show a positive trend, indicating an increase in the number of warm days and nights. Cold extreme indices show a decreasing trend. (TX10P) and (TN10P) show significant negative trends in all stations and indicate a decrease in cold days and nights. Number of frost day index shows a decreasing trend. Overall, the results revealed a decrease in the severity and frequency of cold events, while warm events during the study period were significantly increased. Comparison of years with the highest rainfall and those with the lowest, showed that the amplitude of fluctuations in precipitation in different years is very high and the distribution of rainfall at distinct stations is different.

Conclusion :

The results showed that intense warm indices, such as the summer day index, the number of tropical regions Warm nights, days, and nights have increased, while during the study period, severe cold indices have decreased. Trends, which show a decrease in the intensity and frequency of cold events. the door There was no significant trend in rainfall indices during the study period.

کلیدواژه‌ها [English]

  • Climatic parameters
  • Rainfall indices
  • Temperature indices
  • Trend
  1. Rahimzadeh, F; Hidayat Dezfuli, A; Pourasgharian, A;, 2011, "Evaluation of the trend and change of extreme temperature and rainfall profiles in Hormozgan province," Geography and Development Magazine, Volume 21, pp. 116-97.
  2. Abbasi, F; Javanshiri, Z; Malboosi, Sh.; Partners; 2018. "Research plan for detecting and updating climate change in the country's stations (period 1958-2017) ," National Climatology Center Research Institute, Mashhad.
  3. Erfanian, M.; Ansari, H; Alizadeh; Banayan first, M.; 2014. "Investigation of changes in meteorological limit indices in Razavi Khorasan province," Iran Irrigation and Drainage Journal, Volume 8, No. 4, pp. 825-817
  4. Kuzegran, S; Mousavi Baighi, M., 2015. "Investigating the trend of climatic extreme events in Northeast Iran," Water and Soil Journal (Agricultural Sciences and Industries), Volume 29, No. 3.
  5. Massoudian, S., A. Darend, 2011. "Synonymous Analysis of Extreme Colds of Iran", Geography and Development Quarterly, Volume 9, No. 22. pp. 165-185.
  6. Masoudian, S. , A. Darend, 2012. "Temporal-spatial analysis of the trend of extreme cold days in Iran," Geographical Research, Volume 27, No. 105.
  7. Alexander, L.V., Zhang, X., Peterson, T.C., Caesar, J., Gleason, B., Klein Tank, A.M.G., Haylock, M., Collins, D., Trewin, B., Rahimzadeh, F. and Tagipour, A., 2006. “Global observed changes in daily climate extremes of temperature and precipitation. Journal of Geophysical,” Research: Atmospheres, 111(D5).
  8. Bonsal, B.R., Zhang, X., Vincent, L.A. and Hogg, W.D., 2001. Characteristics of daily and extreme temperatures over Canada. Journal of climate, 14(9), pp.1959-1976.
  9. Darand, M., 2020. Future changes in temperature extremes in climate variability over I ran. Meteorological Applications, 27(6), p.e1968.
  10. DeGaetano, A.T., 1996. Recent trends in maximum and minimum temperature threshold exceedences in the northeastern United States. Journal of Climate, 9(7), pp.1646-1660.
  11. Fathian, F., Ghadami, M., Haghighi, P., Amini, M., Naderi, S. and Ghaedi, Z., 2020. Assessment of changes in climate extremes of temperature and precipitation over Iran. Theoretical and Applied Climatology, 141, pp.1119-1133.
  12. Guijarro, J, "Climatol R package," http://cran.r-project.org/packages/climatol.pdf, 2016.
  13. IPCC, (2007), In: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., Miller, H.L. (Eds.), Climate Change ,2007, The Physical Science Basis. Contribution of Working Group I to The Fourth Assessment Report of The Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom/ New York, USA.
  14. IPCC; Watson; Core;, "Synthesis Report, A Contribution of Working Groups. I, II and III to the third Assessment Report of the Intergovernmental Panel on Climate Change," Climate Change ,2001, Cambridge University press., Cambridge United Kingdom , and New York, USA.
  15. Karl, T.R. and Knight, R.W., 1998. Secular trends of precipitation amount, frequency, and intensity in the United States. Bulletin of the American Meteorological society, 79(2), pp.231-242.
  16. Kattenberg, A; Filippo G;2001. "The Third Assessment Report of the Intergovernmental Panel on Climate Change," The scientific of climate change , Cambridge University Press, pp. pp.156-159.
  17. Mahsafar, H., Maknoon, R. and Saghafian, B., 2010. The impact of climate change on Urmia Lake water level. Iran-Water Resources Research, 7(1), pp.47-58.
  18. Plummer, N., Salinger, M.J., Nicholls, N., Suppiah, R., Hennessy, K.J., Leighton, R.M., Trewin, B., Page, C.M. and Lough, J.M., 1999. Changes in climate extremes over the Australian region and New Zealand during the twentieth century. Weather and climate extremes: Changes, variations and a perspective from the insurance industry, pp.183-202.
  19. Plummer, N., Salinger, M.J., Nicholls, N., Suppiah, R., Hennessy, K.J., Leighton, R.M., Trewin, B., Page, C.M. and Lough, J.M., 1999. Changes in climate extremes over the Australian region and New Zealand during the twentieth century. Weather and climate extremes: Changes, variations and a perspective from the insurance industry, pp.183-202.
  20. Rahimi, M. and Fatemi, S.S., 2019. Mean versus extreme precipitation trends in Iran over the period 1960–2017. Pure and Applied Geophysics, 176, pp.3717-3735.
  21. Rydén, J., 2011. Statistical analysis of temperature extremes in long-time series from Uppsala. Theoretical and applied climatology, 105, pp.193-197.
  22. Salahuddin, A. and Curtis, S., 2011. Climate extremes in Malaysia and the equatorial South China Sea. Global and Planetary Change, 78(3-4), pp.83-91.
  23. Sensoy, S., Türkoğlu, N., Akçakaya, A., Ekici, M., Demircan, M., Ulupinar, Y., Atay, H., Tüvan, A. and Demirbaş, H., 2013, April. Trends in Turkey climate indices from 1960 to 2010. In 6th Atmospheric science symposium (Vol. 24, p. 26).
  24. Sohrabi, M.M., Ryu, J.H., Abatzoglou, J. and Tracy, J., 2013. Climate extreme and its linkage to regional drought over Idaho, USA. Natural Hazards, 65, pp.653-681.
  25. Taghavi, F.A.R.A.H.N.A.Z., 2010. Linkage between climate change and extreme events in Iran. Journal of the Earth & Space Physics, 36(2), pp.33-43.

 

  1. Varfi, M.S., Karacostas, T.S., Makrogiannis, T.J. and Flocas, A.A., 2009. Characteristics of the extreme warm and cold days over Greece. Advances in Geosciences, 20, pp.45-50.
  2. World Meteorological organization, The global climate 2001-2010, A decade of climate extremes, summary report, No.1119, 2013.
  3. Zhai, P., Sun, A., Ren, F., Liu, X., Gao, B. and Zhang, Q., 1999. Changes of climate extremes in China. Weather and Climate Extremes: Changes, Variations and a Perspective from the Insurance Industry, pp.203-218.
  4. Zhao, C., Wang, W. and Xing, W., 2012. Regional analysis of extreme temperature indices for the Haihe river basin from 1960 to 2009. Procedia Engineering, 28, pp.604-607.