Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30127
Analysis of Trend and Variability of Rainfall in the Mid-Mahanadi River Basin of Eastern India

Authors: Rabindra K. Panda, Gurjeet Singh

Abstract:

The major objective of this study was to analyze the trend and variability of rainfall in the middle Mahandi river basin located in eastern India. The trend of variation of extreme rainfall events has predominant effect on agricultural water management and extreme hydrological events such as floods and droughts. Mahanadi river basin is one of the major river basins of India having an area of 1,41,589 km2 and divided into three regions: Upper, middle and delta region. The middle region of Mahanadi river basin has an area of 48,700 km2 and it is mostly dominated by agricultural land, where agriculture is mostly rainfed. The study region has five Agro-climatic zones namely: East and South Eastern Coastal Plain, North Eastern Ghat, Western Undulating Zone, Western Central Table Land and Mid Central Table Land, which were numbered as zones 1 to 5 respectively for convenience in reporting. In the present study, analysis of variability and trends of annual, seasonal, and monthly rainfall was carried out, using the daily rainfall data collected from the Indian Meteorological Department (IMD) for 35 years (1979-2013) for the 5 agro-climatic zones. The long term variability of rainfall was investigated by evaluating the mean, standard deviation and coefficient of variation. The long term trend of rainfall was analyzed using the Mann-Kendall test on monthly, seasonal and annual time scales. It was found that there is a decreasing trend in the rainfall during the winter and pre monsoon seasons for zones 2, 3 and 4; whereas in the monsoon (rainy) season there is an increasing trend for zones 1, 4 and 5 with a level of significance ranging between 90-95%. On the other hand, the mean annual rainfall has an increasing trend at 99% significance level. The estimated seasonality index showed that the rainfall distribution is asymmetric and distributed over 3-4 months period. The study will help to understand the spatio-temporal variation of rainfall and to determine the correlation between the current rainfall trend and climate change scenario of the study region for multifarious use.

Keywords: Eastern India, long-term variability and trends, Mann-Kendall test, seasonality index, spatio-temporal variation.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1125001

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1089

References:


[1] Dore, Mohammed HI. "Climate change and changes in global precipitation patterns: what do we know?" Environment international vol. 31, no. 8, pp. 1167-1181, 2005.
[2] Da-Quan, Zhang, Feng Guo-Lin, and Hu Jing-Guo. "Trend of extreme precipitation events over China in last 40 years." Chinese Physics, vol. 17, no. 2, pp. 736, 2008.
[3] Bhaskaran, B., J. F. B. Mitchell, J. R. Lavery, and M. Lal. "Climatic response of the Indian subcontinent to doubled CO2 concentrations." International Journal of Climatology, vol. 15, no. 8, pp. 873-892, 1995.
[4] May, W. "Simulation of the variability and extremes of daily rainfall during the Indian summer monsoon for present and future times in a global time-slice experiment." Climate Dynamics, vol. 22, no. 2-3, pp. 183-204, 2004.
[5] Gosain, A.K., Sandhya Rao and Debajit Basuray. “Climate change impact assessment on hydrology of Indian river basins”. Current Science, vol. 90, no.3, pp. 346-353, 2006.
[6] Turner, Andrew G., and Hariharasubramanian Annamalai. "Climate change and the South Asian summer monsoon." Nature Climate Change, vol. 2, no. 8, pp. 587-595, 2012.
[7] H.B., Mann. “Non-parametric tests against trend”,1945 Econometrica 13:163-171.
[8] M.G. Kendall. Rank Correlation Methods. 4th edition, Charles Griffin, London, U.K, 1975.
[9] Walsh, R. P. D., and D. M. Lawler. "Rainfall seasonality: description, spatial patterns and change through time." Weather, vol. 36, no. 7, pp. 201-208, 1981.
[10] Guhathakurta, Pulak, and Elizabeth Saji. "Detecting changes in rainfall pattern and seasonality index vis-à-vis increasing water scarcity in Maharashtra." Journal of Earth System Science, vol. 122, no. 3, pp. 639-649, 2013.
[11] Kanellopoulou, E. A. "Spatial distribution of rainfall seasonality in Greece." Weather, vol. 57, no. 6, pp. 215-219, 2002.
[12] Mohapatra, M., and U. C. Mohanty. "Spatio-temporal variability of summer monsoon rainfall over Orissa in relation to low pressure systems." Journal of earth system science, vol. 115, no. 2, pp. 203-218, 2006.