Volume 5, Number 13 (3-2017)                   DEEJ 2017, 5(13): 101-116 | Back to browse issues page


XML Persian Abstract Print


Abstract:  

In this research, for analysis the spatial- temporal changes of precipitation in Iran, the monthly data of GPCC data base in the spatial resolution of 0.5°×0.5° during 40 years period(1974- 2013) have been used. In order to analyze the spatial character of precipitation, the mean of annual, seasonal and monthly amounts of precipitation were prepared and then by applying IDW method in GIS, 17 average maps were produced. To examine the temporal trend of precipitation, first 17 graphs were prepared using the weighted amount of precipitation and then the trend was evaluated using Mann-Kendall nonparametric test at 0.95 level of significance. The results from this study indicated that the pixel based precipitation amount is 255.22 mm. the max of precipitation is located on the west shores of the Caspian sea and the highlands of Zagros and the min of precipitation is generally seen at the central, eastern and south-eastern extents of the country. The amount of precipitation is reduced by crossing from north, north-west and west toward central, eastern and southern regions.  The winter and summer amounts of precipitation is 79.6 and 11.5 mm and these two seasons are regarded to be the wettest and driest seasons respectively. The max of winter precipitation is seen on the western shores and the peaks of Zagros Mountains while the min precipitation in this season is on the central, eastern and southern areas of the country. The analysis of monthly precipitation maps of the country revealed two temporal groups of precipitation: The months of November, December, February, March and April with the mean precipitation of 23.3 mm are considered the wettest months and the months of May, June, July, August, September and October are the driest months in the country. The examination of annual amounts of precipitation indicated a significant downward trend at 0.95 level of significance.  From 1992 to 2013 it has been a decreasing trend in annual amount of precipitation in Iran. Only in winter there has been a significant downward trend and in none of the other seasons no meaningful trend was detected. The analysis of precipitation revealed no significant trend on monthly time series at the 0.95 level of significance.

Type of Study: Research | Subject: Climatology
Received: 2016/06/28 | Accepted: 2016/12/20 | Published: 2017/02/26

References
1. Ampitiyawatta, A.D., ShenglianGuo, 2009. precipitation trends in the kalu Ganga basin in srilanka, The Journal of Agricultural Science, vol.4, no.1: 10-18.
2. Baldwin, M.E, and S.Lakshmivarahan, 2009. Rainfall classification using histogram analysis: An example of data mining in meteorology. Technical Report, School of Computer Science, University of Oklahoma, Norman, Ok.
3. Chaouche, K. Luc Neppel, Claudine Dieulin, Nicolas Pujol, Bernard Ladouche , Eric Martin , Dallas Salas , Yvan Caballero, 2010, Analyses of precipitation, temperature and evapotranspiration in a French Mediterranean region in the context of climate change. C. R. Geoscience 342 (2010) 234–243.
4. DE LUIS. M, Raventos. J.C, Hidalgo. Gonzalez and Longares. L.A, 2010. Is rainfall erosivity increasing in the Mediterranean Iberian Peninsula? Land degradation & development, 21: 139-144.
5. Drosdowsky Wasyl. 1993. An analysis of Australian seasonal rainfall anomalies 1950- 1987. Inter journal climatological. Vol 13.
6. Gandomkar, A. Soltani Gord faramarzi, T. Safaripour Chafi, P. Amani, A.R, 2011. Analysis of Precipitation and Temperature Trends in Sefid-Roud Basin; World Academy of Science, Engineering and Technology 59 2011.
7. Gemmer, M., S. Becker, T. Jiang, 2004. Observed monthly precipitation trendsin China 1951–2002, Theor. Appl. Climatol. 77, 39–45.
8. Hartman, H., Andresky, L., 2013. flooding in Indus River Basin – A Spatiotemporal Analysis of Precipitation Records, Global and planetary change, Available online 12 April 2013.
9. IndraniPal, Abir Al-Tabbaa, 2009. Trends in seasonal precipitation extremes – An indicator of ‘climate change’ in Kerala, India, Journal of Hydrology 367: 62–69.
10. Javanmard, S., Yatagai, A., Nodzu, M. I., Bodaghjamali, J., Kawamoto, H. 2010. Comparing high-resolution gridded precipitation data with satellite rainfall estimates of TRMM_3B42 over Iran, Advances in Geosciences, Volume 25, pp.119- 125.
11. Jayawardene, H.K.W.I., D.U.J. Sonnadara, and D.R. Jayewardene, 2005. Trends of Rainfall in Sri Lanka over the Last Century, Sri Lankan Journal of Physics, Vol. 6 : 7-17.
12. Jiang, T., Su, B., Hartmann, H., 2007. Temporal and spatial trends of precipitation and river flow in the Yangtze River Basin, 1961–2000, Geomorphology, Volume 85, Issues 3–4, 143–154.
13. Kim, J. S. and Jain, S., 2011. Precipitation trends over the Korean peninsula: typhoon- induced changes and a typology for characterizing climate-related risk, Environ. Res. Lett. 6,034033:1-6.
14. Keykhosravi kiani, M.S., 2012. Comprative analysis of gird data of Asfezari precipitation and GPCC and GPCP, M.Sc. thesis, University of Isfahan. 88 pp.
15. Mamedov, R.M., Safarov, S.G., Safarov, E.S., 2009. Current changes of the atmospheric precipitation regime on the territory of Azerbaijan, Geography and Natural resources, Volume 30, Issue 9, PP 403-407.
16. Masoodian, A., 2011. Climate of Iran, Sharieh toos, Mashhad, Iran.
17. Masoodian, A., Keykhosravi kiani, M.S., Rayatpishe, F., 2014. Introduction and Comparison of Asfezari precipitation database and GPCC, GPCP and CMAP Database, Journal of geographical research112, 73-87.
18. Merianji, Z., 2012. Variability of precipitation regim in Iran, ph.D thesis, University of Isfahan.
19. Mohamadi, B., 2012. Trend analysis of annual rainfall over Iran, Journal of Geography and environmental planning 22 (3), 95-106.
20. Mohamadi, H., 2010. Applied climatology, Tehran University, Tehran.
21. Mondal1, A; S. Kundu1, A. Mukhopadhyay, 2012, rainfall trend analysis by mann-kendall test: a case study of north-eastern part of cuttack district, orissa; International Journal of Geology, Earth and Environmental Sciences; Vol. 2 (1) January-April, pp.70-78.
22. Mosmann, V., Castro, A., Fraile, R., Dessens, J., Sanchez, J., 2004. Detection of statistically trends in summer precipitation of mainland Spain, Atmospheric research, 70, 1, 43-53.
23. Sen Roy, S., Rouault, M., 2013. Spatial Pattern of seasonal scale trends in extreme hourly precipitation in South Africa, Applied Geography, 39, 151-157.
24. Turgay, P. and Ercan K. 2005. Trend Analysis in Turkish Precipitation data, Hydrological Processes, vol. 20, Issue 9, pp.2011-2026.
25. UnkasÏevic, M and Radinovic, D., 2000. Statistical Analysis of Daily Maximum and Monthly Precipitation at Belgrade, J. Theor and Applied Climatol, 66: 241-249.
26. Vivekanandan, N., 2007. Analysis of trend in rainfall using Non Parametric statistical methods, international symposium on rainfall rate and radio wave propagation, American institute of physics. P: 101-113.
27. Wan. L, Zhang. X.P, Ma. Q, Sun. Y.P, Ma. T.Y, Zhang. J.J., 2011. spatiotemporal trends of precipitation on the loess Plateau of china, 19th International Congress on Modelling and Simulation, Perth, Australia, 12–16.
28. Will mottt. C. J., 1978. P-mode principal components analysis, grouping and precipitation regions in California, archive for meteo. Ser. B. Vol 26. No 4.
29. http://www.esrl.noaa.gov/psd/data/gridded/data.gpcp.html

Add your comments about this article : Your username or email:
Write the security code in the box

Send email to the article author


© 2015 All Rights Reserved | Desert Ecosystems Engineering Journal

Designed & Developed by : Yektaweb