Global warming, climate change and its consequences are major threat for the global agriculture. The agriculture in the North-East region of India is supposed to more in danger due to its topographic features. Agriculture in the state of Arunachal Pradesh is dependent on rainfall and variability in rainfall due to climate change is expected to threaten the food production in future. This study examines the impact of climate change on rainfall using the trend analysis technique for the four districts of Arunachal Pradesh. For this purpose temporal trends in annual and seasonal rainfall were detected using nonparametric Mann-Kendall test at 5% significance level. The daily time series rainfall data for the period 1971-2007 were analyzed statistically for each district separately. The results of Mann Kendall test showed decreasing trend in annual mean rainfall in east Siang, upper Siang and lowers Dibang valley and no trend in the west Siang district over the period of 1971-2007. In case of east Siang, upper Siang and lower Dibang valley districts, decreasing trend of rainfall was observed in the post monsoon season with slope magnitude of 3.01 mm/yr, 3.32 mm/yr and 3.95 mm/yr respectively. Decreasing pattern of rainfall in post monsoon season may affect the vegetable and fruit production in the winter season.
Climate change, Mann-Kendall, Rainfall, Seasonal, Trend analysis
Choudhury, B. U., Das, A., Ngachan S. V., Slong, A., Bordoloi, L. J. and Chowdhury, P. (2012). Trend analysis of long term weather variables in mid altitude Meghalaya, North-East India. Journal of Agricultural Physics, 12 (1): 12-22.
INCCA (2010). Indian network for climate change assessment, Climate Change and India: A 4x4 Assessment, Ministry of Environment and Forests, Government of India, 2010.
IPCC (2001). Climate change: the scientific basis. Intergovernmental panel on climate change. Cambridge (UK): Cambridge Univ. Press.
Hamed, K. H. and Rao, A. R. (1998). A modified Mann-Kendall trend test for auto-correlated data. Journal of Hydrology, 204:182-196.
Kendall, M.G. (1955). Rank Correlation Methods, Charles Griffin: London.
Kendall, M. G. (1975). Rank Correlation Methods, 4th edition. Charles Griffin, London, U. K.
Kothyari, U. C. and Singh, V. P. (1996). Rainfall and temperature trends in India. Hydrological Processes, 10: 357â€“372.
Krishna Kumar, K., Patwardhan, S. K., Kulkarni, A., Kamala, K., KoteswaraRao, K. and Jones, R. (2011). Simulated projections for summer monsoon climate over India by a high-resolution regional climate model (PRECIS). Current Science, 101(3): 312-26.
Krishnakumar, K. N., Prasada Rao, G. S. L. H. V. and Gopakumar, C. S. (2009). Rainfall trends in twentieth century over Kerala, India. Atmospheric Environment, 43(11): 1940-1944.
Kumar, K. K., Kumar, K. R., Ashrit, R. G., Deshpande, N. R. and Hansen, J. W. (2004). Climate impacts on Indian agriculture. International Journal of Climatology, 24 (11): 1375â€“93.
Kumar, V. and Jain, S. K. (2010). Trends in seasonal and annual rainfall and rainy days in Kashmir Valley in the last century. Quaternary International, 212(1): 64-69.
Mall, R. K., Singh, R., Gupta, A., Srinivasan, G. and Rathore, L. S. (2006). Impact of climate change on Indian agriculture: A review. Climatic Change, 78 (2-4): 445-78.
Mann, H. B. (1945), Non-parametric test against trend. Econometrica, 13:245â€“259.
Mondal, A., Kundu, S. and Mukhopadhyay, A. (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, 2(1):70-78.
Partal, T. and Kahya, E. (2006). Trend analysis in Turkish precipitation data. Hydrological processes, 20: 2011-2026.
Sen, P. K. (1968). Estimates of the regression coefficient based on Kendallâ€™s tau. Journal of the American Statistical Association, 39: 379â€“1389.
Sinha, S. K., Singh, G. B. and Rai, M. (1998). Decline in crop productivity in Haryana and Punjab: Myth or reality. Indian Council of Agricultural Research, New Delhi, India, 89.
Patle, G. T., Singh, D. K., Sarangi, Rai, A., Khanna, M. and Sahoo, R. N. (2013). Temporal variability of climatic parameters and potential evapotranspiration. Indian journal of Agricultural Sciences, 83 (4): 518-524.
Sarangi, A. And Kumar, A. (2009). Trend analysis of long term rainfall data for crop planning as an adaptation measure to climate change. 60th International Executive Council Meeting & 5 th Asian Regional Conference, 6-11 December 2009, New Delhi, India: 1-6.
Soman, M. K., Krishna Kumar, K. and Singh, N. (1988). Decreasing trend in the rainfall of Kerala. Current Science, 57: 7â€“12.
Yue, S. and Hashino, M. (2003). Long term trends of annual and monthly precipitation in Japan. Journal of the American Water Resources Association, 39: 587â€“96.
This work is licensed under Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) © Author (s)