Precipitation Trend Analysis in Zohre-Jirahi Basin in Kohgiluyeh and Boyer-Ahmad Province

Subject Areas : Hydrology, hydraulics, and water transfer buildings

Amirabbas Mahmoudian Bidgoli ¹ , Mohammadsadegh Sadeghian ² , Ali Saremi ³ , hooman Hajikandi ⁴

1 - Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
2 - Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
3 - Department of Water Engineering and Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran
4 - Department of Civil Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran.

Received: 2022-08-20 Accepted : 2022-10-16 Published : 2023-07-23

Keywords: Mann-Kendall, Sen's slope, Kohgiluyeh and Boyer-Ahmad, Precipitation, Trend analysis,

Abstract :

Background and Aim: Water resources management has long been the focus of residents in Iran. Knowing of the time and the amount of rainfall contributes to better planning for water resources management, and this can be examined according to the available statistical data. The need for knowledge about precipitation trends in the study areas facilitates and legalizes water resources management and planning and helps to supply water with a higher reliability factor. The purpose of this research is to estimate and analyze the precipitation trends in Kohgiluyeh and Boyer-Ahmad Province within the  Zohre-Jirahi basin.Method: This research is carried out in the Zohre-Jirahi basin in Kohgiluyeh and Boyer-Ahmad province based on the data from 1966 to 2018. In this regard, first, meteorological stations related to the studied area were located and their statistics were extracted from the received data. The stations’ data homogeneity is calculated based on the Kolmogorov-Smirnov method, and those without homogeneous data or with limited data are removed and, 30 stations are selected for data rebuilding. Rebuilding of missing data is done with Inverse Distance Weighted methods with the power of two and ordinary linear Kriging and after evaluating the methods by three criteria of Root Mean Square Error, Mean Absolute Error, and Coefficient of Determination, the optimal method is selected to rebuild the missing data in this study area. After rebuilding the data, a multi-dimensional raster containing rainfall information related to the years of the statistical period is produced and the time series of the relevant data is created in an array and per surface unit. In this research, according to the surface of the study area, time series of 8915 points are analyzed, and the trend of changes based on the Mann-Kendall method and Sen's slope on an annual and monthly scale are assessed in these points and, raster maps are produced.Results: Among the methods used for rebuilding missing data, based on the evaluation of the models, the optimal method for rebuilding missing data in the study area was the Inverse Distance Weighted method with a coefficient of determination of 0.95.The results of calculations on an annual scale show that the average Sen's slope in the study area does not have a significant trend and is equal to 0.0011. The average Sen's slope in the study area on a monthly scale is 0.28 in April and has an upward trend, in May Sen's slope is equal to -0.03 and indicates a downward trend and in June and July, an unobserved trend, and the results of Sen's slope calculations are zero. In August, there is an upward trend, and it’s value is equal to 0.11. In September, there is an upward trend, and it is equal to 0.06. In October, there is no observed trend, and it is equivalent to zero. In November and December, the trend is upward, and the average Sen's slope in the study area is equal to 0.19 and 0.62, respectively, and in January, February and March, the downward trend is equal to -0.48, -0.55, and -0.14.Conclusion: The results do not demonstrate a significant trend on an annual scale, however on a monthly scale, in December, April, November, August, and September, respectively, the highest upward trend is observed, while in February, December, March, and May, respectively, have the highest downward trend, and June, July, and October lack trends. The maximum average Sen's slope is calculated for December and equal to 0.62, and its minimum is in February and equal to -0.55. The management of water resources, especially in the agricultural sector as the main consumer, has large economic and social dimensions and is inevitable, and due to the great impact of water supply time to optimize and increase productivity, this research can be used to review the pattern and time of cultivation in this area. Groundwater artificial recharge, storage process, and consumption process should adapt to the new changes.

References:

Bhusal, A., Parajuli, U., Regmi, S., Kalra, A. (2022). Application of Machine Learning and Process-Based Models for Rainfall-Runoff Simulation in DuPage River Basin, Illinois. Hydrology, 9(7), 117. doi:10.3390/hydrology9070117

Ceyhunlu, A., and Ceribasi, G. (2021). Analysis of total monthly precipitation of Susurluk Basin in Turkey using innovative polygon trend analysis method. Journal of Water and Climate Change |, 12, 1532-1543. doi:10.2166/wcc.2020.253

Dad, J., Muslim, M., Rashid, I., Rashid, I., Reshi, Z., (2021). Time series analysis of climate variability and trends in Kashmir Himalaya. Ecological Indicators, 126, 107690. doi: 10.1016/j.ecolind.2021.107690

Fung , K., Chew , K., Huang, Y., Ahmed, A., Teo, F., Ng, J., and Elshafie, A. (2022). Evaluation of spatial interpolation methods and spatiotemporal modeling of rainfall distribution in Peninsular Malaysia. Ain Shams Engineering Journal, 13(2), 101571. doi: 10.1016/j.asej.2021.09.001

Harka, A., Jilo, N., Behulu, F. (2021). Spatial-temporal rainfall trend and variability assessment in the Upper Wabe Shebelle River Basin, Ethiopia: Application of innovative trend analysis method. Journal of Hydrology: Regional Studies, 37, 100915. doi: 10.1016/j.ejrh.2021.100915

Hossain, S., Mingying, M., Delin, H. (2020). Climate Change in Bangladesh: Evidence from Temperature, Precipitation, and Rainfall. International Journal of Arts Humanities and Social Sciences Studies, 5(10), 80-88.

Kamble, P., and Ovhal, V. (2018). Green Economy in Developing Countries: An Analytical Study. Journal of Shivaji University (Humanities and Social Sciences), 51(1), 24-37.

Luiz, A. J., and Lima, M. A. (2021). Application of the Kolmogorov-Smirnov test to compare greenhouse gas emissions over time. Brazilian Journal of Biometrics, 39(1), 60-70. doi:10.28951/rbb.v39i1.498

Mojtaba, N., and Ghermezcheshmeh, b. (2019). Investigating the rainfall trend suitable opportunities for harvesting rainwater (case study of Caspian region). 8th National Conference on Rainwater Catchment Systems (p. 11). Mashhad: Ferdowsi university. (in Farsi)

Rai, S., Dahal, B., Anup, K. (2022). Climate change perceptions and adaptations by indigenous Chepang community of Dhading, Nepal. GeoJournal. doi:10.1007/s10708-022-10577-9

Sari, R., and komarudin, a. (2021). Confirmatory Factor Analysis (CFA) Model for Testing Normality with the Weight Least Square (WLS) Estimation Method. Jurnal Sains dan Teknologi, 13(1), 12-20. doi:10.31958/js.v13i1.3169

Tantoh, H. B. (2021). Water metering in piped community-based water supply systems: the challenge of balancing social and economic benefits. Development in Practice, 31, 781-793. doi:10.1080/09614524.2021.1937546

Vyver, H. (2012). Spatial regression models for extreme precipitation in Belgium. Water Resources Research, 48(9). doi:10.1029/2011WR011707

Wang, Y., Xu, Y., Tabari, H., Wang, J., Wang, Q., Song, S., and Hu, Z. (2020). Innovative trend analysis of annual and seasonal rainfall in the Yangtze River Delta, eastern China. Atmospheric Research, 104673. doi:10.1016/j.atmosres.2019.104673.