Abstract
Study of changes in the global solar radiation is one of the key factors in sustainable agricultural production and management. Therefore, we investigated trends in the solar radiation using sunshine duration as a suitable alternative, based on the recommendation of the FAO Irrigation and Drainage—Paper No. 56, by using the Mann-Kendall (MK) test at different time scales in the humid environments of Northeast India. The average annual bright sunshine hours over Agartala is found to be 6.6 hours (h) with a standard deviation of 0.4 h and coefficient of variation of 6.4%. On annual (seasonal) time scale, statistically significant decreasing trends in bright sunshine duration through the MK test were observed at 5% level of significance at the rate of 0.245 h/decade (0.545 and 0.118 h/decade in winter and monsoon) over Agartala. Similarly, sunshine decreases were observed in the months of January, February, March, May, September, October, and December in the range of 0.237–0.688 h/decade. The observed decreases in sunshine duration modify the evapotranspiration process and affect the crop water requirements, which, in turn, will negatively influence the agricultural production in humid environments of Northeast India.
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Acknowledgements
The authors thank the India Meteorological Department (Pune) for providing the climatic data used in this study.
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Jhajharia, D. et al. (2018). Changes in Sunshine Duration in Humid Environments of Agartala (Tripura), India. In: Singh, V., Yadav, S., Yadava, R. (eds) Climate Change Impacts. Water Science and Technology Library, vol 82. Springer, Singapore. https://doi.org/10.1007/978-981-10-5714-4_2
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DOI: https://doi.org/10.1007/978-981-10-5714-4_2
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