بررسی روند تغییرات دما، بارندگی و رطوبت نسبی در ایران

نوع مقاله: مقاله پژوهشی

نویسندگان

1 کارشناس ارشد مهندسی منابع آب، دانشگاه شهید چمران اهواز.

2 استاد دانشکده مهندسی علوم آب، دانشگاه شهید چمران اهواز

3 دانشیار دانشکده علوم و مهندسی آب، دانشگاه شهید چمران اهواز .

4 دانشیار دانشکده علوم و مهندسی آب، دانشگاه شهید چمران اهواز.

چکیده

اولین گام در راستای آشکارسازی و چگونگی تغییر اقلیم بررسی ناهنجاری و نوسانات ایجاد شده در پارامترهای اقلیمی میباشد. در این تحقیق به بررسی روند تغییرات پارامترهای اقلیمی دما، بارندگی و رطوبت نسبی در مقیاس‌ زمانی سالانه در 37 ایستگاه سینوپتیک کشور (2010-1961) با استفاده از آزمون‌های آماری ناپارامتریک من-کندال و تخمین‌گر شیب سن پرداخته شده است. به‌طور کلی نتایج حاکی از روند افزایشی دما و روند کاهشی بارندگی و درصد رطوبت نسبی در اکثریت نقاط کشور می‌باشد. در کل کشور به غیر از ایستگاه‌های مرتفع و کوهستانی شهرکرد، خرم‌آباد و سقز روند افزایشی دما مشاهده شد که بیشترین افزایش معنی‌دار دما (سطح اطمینان 95درصد) در ایستگاه‌های مشهد، زاهدان، زابل، بم، یزد، بابلسر، کرمانشاه، آبادان، خوی و تبریز به میزان 1.5 درجه‌ی سانتی‌گراد در طی 50 سال می‌باشد. روند کاهش بارندگی خصوصاً در نیمه‌ی شرقی، غرب و شمال غرب کشور مشاهده گردید که بیشترین کاهش بارندگی معنی‌دار (سطح اطمینان 95 درصد) در  شمال غرب کشور و در حدود 3.2 میلی متر در سال می‌باشد. روند کاهش رطوبت نسبی در اغلب نواحی به غیر از قسمتی در ناحیه‌ی شمال غرب و جنوب دریای خزر مشاهده شد که بیشترین کاهش معنی‌دار در سطح اطمینان 95 درصد در ایستگاه‌های آبادان، زاهدان و کرمانشاه در حدود 4.1 درصد در 50 سال گذشته می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Trend Analysis of Temperature, Precipitation, and Relative Humidity Changes in Iran

نویسندگان [English]

  • Anahita Eblaghian 1
  • Ali mohammad Akhondali 2
  • Fereydon Radmanesh 3
  • Heidar Zarei 4
1 M.Sc. of Hydrology and Water Resource Engineering Department of Shahid Chamran University of Ahvaz, Iran.
2 professor, faculty member of Hydrology and Water Resource Engineering Department of Shahid Chamran University of Ahvaz, Iran
3 Associate professor, faculty member of Hydrology and Water Resource Engineering Department of Shahid Chamran University of Ahvaz, Iran.
4 Associate professor, faculty member of Hydrology and Water Resource Engineering Department of Shahid Chamran University of Ahvaz, Iran.
چکیده [English]

Introduction
In the pursuit of detecting the trend and the shift in trend in hydro-meteorological variables, various statistical methods have been developed and used over the years. Of the two methods commonly used (parametric and non-parametric), the non-parametric method has been favored over parametric methods. Long term trend analysis can reveal the beginning of the trend year, trend changes over time, and abrupt trend detection in a time-series. It is expected that the findings of this study will bring about more insights on understanding the regional hydrologic behavior over the last several decades in Iran.
 
Methodology
This paper analyzes the behavior of annual and seasonal temperatures, precipitation, and relative humidity. Datasets of 37 stations in Iran were analyzed from 1961 to 2010. The
 pre-whitening technique was used to eliminate the effect of the autocorrelation of data series. The Mann–Kendall (MK) test and the Sen's slope estimator were applied to quantify the significance of the trend and the magnitude of the trend at a 95% confidence level, respectively. The surface interpolation technique was used to prepare a spatial temperature, precipitation, and relative humidity data map over Iran from the point data measuring stations within the ArcGIS framework. For spatial distribution of trends in maps, contours are generated using an inverse-distance-weighted (IDW) algorithm.

کلیدواژه‌ها [English]

  • Trend
  • Nonparametric tests
  • Mann-Kendall test
  • Sen's Slope Estimator

1- Akhondali, A.M. and Zarei, h., 2012. Comparison of statistical methods and classical statistics in hydrograph drawings of groundwater unit. Second National Conference Irrigation and Drainage Network Management. Shahid Chamran University of Ahvaz , Ahvaz. Iran. (In Persian).

 

2- Anonymous, 2009. Climate change and agriculture specific review - review of the convention and climate change summits from Rio to Copenhagen. Agricultural Education Publishing Publishing. Tehran. 32 pages. (In Persian).

 

3- Brooks, C.E.P. and Carrthers, N. 1953. Handbook of Statistical Methods in Meteorology.London. H.M.S.O, pp 412.

 

4- Chen, H., Guo, S., Xu, C.Y. and Singh, V.P., 2007. Historical temporal trends of hydro-climatic variables and runoff response to climate variability and their relevance in water resource management in the Hanjiang basin. Journal of Hydrology344(3), pp.171-184.

 

5- Deshmukh, D.T. and Lunge, H.S., 2013. Trend Assessment in Climatic Variables by Mann-Kendall and t-test: A Case Study of Yavatmal District in Vidarbha, India. Statistics2, pp.597-600.

 

6- Dinpashoh, Y., Jhajharia, D., Fakheri-Fard, A., Singh, V.P. and Kahya, E., 2011. Trends in reference crop evapotranspiration over Iran. Journal of Hydrology399(3), pp.422-433.

 

7- Feyzi, V., Farajzadeh, M. and Norozi, R., 2010. Using Mann-Kendall test to Recognize of Climate Change in Sistan VA Balochestan province. 4th International Congress of the Islamic World Geographers (ICIWG). Zahedan. Iran. (In Persian).

 

8- Gharekhani, A. and Ghahreman, N, 2010. Seasonal and Annual Trend of Relative Humidity and Dew Point Temperature in Several Climatic Regions of Iran. Journal of Water and Soil, 24(4), pp.636-646. (In Persian).

 

9- Gilbert, R.O., 1987. Statistical methods for environmental pollution monitoring. John Wiley & Sons.

 

10- Gocic, M. and Trajkovic, S., 2013. Analysis of changes in meteorological variables using Mann-Kendall and Sen's slope estimator statistical tests in Serbia. Global and Planetary Change100, pp.172-182.

 

11- Hejam, S., Khoshkho, Y. and Shamsoldinvandi, R., 2008. Analysis of seasonal and annual rainfall variations of several selected stations in central Iran Using nonparametric methods. Geographical Research Journal, 64, pp. 157-168. (In Persian).

 

12- Johnston, K., Ver Hoef, J.M., Krivoruchko, K. and Lucas, N., 2001. Using ArcGIS Geostatistical Analyst (Vol. 380). Redlands: Esri, pp.113-130.

 

13- Karmeshu, N., 2012. Trend detection in annual temperature & precipitation using the Mann Kendall test–a case study to assess climate change on select states in the northeastern United States. Master of Environmental Studies Capstone Projects, Department of Earth & Environmental Science, University of Pennsylvania.

 

14- Kheshtkarisani, S.and Mehdizadeh, M.,2013. Investigation of Seasonal and Annual Seasonal Rainfall in Urmia Lake Basin Stations Using the Man-Kendall Test. First National Climate Conference of Iran.   University of Advanced Industrial Technology and Advanced Technology. Kerman. Iran. (In Persian).

 

15- Kousari, M.R., Ahani, H. and Hendi-zadeh, R., 2013. Temporal and spatial trend detection of maximum air temperature in Iran during 1960–2005. Global and Planetary Change, 111, pp.97-110.

 

16- Marofi, S. and Tabari, H, 2011. Detection of Maroon River Flow Changes Using Parametric and Nonparametric Methods. Quarterly Journal of Geographic Research, 26(2), pp. 125-146. (In Persian).

 

17- Masah bovani, A., Godarzi, A., Zohrabi, N. and Lotfi, S, 2013. Investigation of the relationship between temperature and precipitation changes and increasing greenhouse gas emissions (Case study of West Azarbaijan Basin). Journal of The Earth and Space Physics. 39(3), pp.111-128. (In Persian).

 

18- Modarres, R. and da Silva, V.D.P.R., 2007. Rainfall trends in arid and semi-arid regions of Iran. Journal of Arid Environments70(2), pp.344-355.

 

19- Modarres, R. and Sarhadi, A., 2009. Rainfall trends analysis of Iran in the last half of the twentieth century. Journal of Geophysical Research: Atmospheres, 114(D3),pp. 1-9.

 

20- Mosaedi, A., Kavakebi, GH. and Abdollahzade, Z, 2011. Detection of Climatic Changes Based on Mann-Whitney Nonparametric test in city of Mashhad. National Conference on Meteorology and Water Management, University of Tehran, Tehran, Iran. (In Persian).

 

21- Partal, T. and Kahya, E., 2006. Trend analysis in Turkish precipitation data. Hydrological Processes20(9), pp.2011-2026.

 

22- Pirnia, A., Teimoori, M,A,E. Omidvar, E., Abkar, A., Habibnejad roshan, M., Soleimani, K., 2009. Investigation of general relationship changes of temperature and precipitation in Mazandaran province and it's comparison with climate changes in northern hemisphere and global scals. 5th National Conference on Watershed Management Sciences and Engineering. Gorgan University of Agricultural Sciences and Natural Resources. (In Persian).

 

23- Salas, J.D., 1980. Applied modeling of hydrologic time series, LLC. Water Resources Publication.

 

24- Sayemuzzaman, M. and Jha, M.K., 2014. Seasonal and annual precipitation time series trend analysis in North Carolina, United States. Atmospheric Research137, pp.183-194.

 

25- Sen, P.K., 1968. Estimates of the regression coefficient based on Kendall's tau. Journal of the American Statistical Association63(324), pp.1379-1389.

 

26- Serrano, A., Mateos, V.L. and Garcia, J.A., 1999. Trend analysis of monthly precipitation over the Iberian Peninsula for the period 1921–1995. Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere24(1), pp.85-90.

 

27- Tabari, H. and Talaee, P.H., 2011. Analysis of trends in temperature data in arid and semi-arid regions of Iran. Global and Planetary Change79(1), pp.1-10.

 

28- Tabari, H., Marofi, S., Aeini, A., Talaee, P.H. and Mohammadi, K., 2011. Trend analysis of reference evapotranspiration in the western half of Iran. Agricultural and Forest Meteorology151(2), pp.128-136.

 

29- Trajkovic, S. and Kolakovic, S., 2009. Wind-adjusted Turc equation for estimating reference evapotranspiration at humid European locations. Hydrology Research40(1), pp.45-52

 

30- Varshavian, V., Khalili, A., Ghahreman, N. and Hajjam, S, 2011. Trend analysis of minimum, maximum, and mean daily temperature extremes in several climatic regions of Iran. Journal of The Earth and Space Physics, 37(1), pp.169-179. (In Persian).

 

31- Von Storch, H., 1995. Spatial patterns: EOFs and CCA. Analysis of Climate Variability, H. von Storch and A. Navarra, Eds, pp. 227-258.

 

32- Xu, Z.X., Takeuchi, K. and Ishidaira, H., 2003. Monotonic trend and step changes in Japanese precipitation. Journal of hydrology279(1), pp.144-150.