The detailed analysis of individual rain events characteristics is an essential step for improving our understanding of variation in precipitation over different topographies. In this study, the homogeneity among rain gauges was investigated using the concept of “rain event properties,” linking them to the main atmospheric system that affects the rainfall in the region. For this, eight properties of more than 23,000 rain events recorded at 47 meteorological stations in Mumbai, India, were analyzed utilizing seasonal (June-September) rainfall records over 2006-2016. The high similarities among the properties indicated the similarities among the rain gauges. Furthermore, similar rain gauges were distinguished, investigated and characterized by cluster analysis using self-organizing maps (SOM). The cluster analysis results show six clusters of similarly behaving rain gauges, where each cluster addresses one isolated class of variables for the rain gauge. Additionally, the clusters confirm the spatial variation of rainfall caused by the complex topography of Mumbai, comprising the flatland near the Arabian Sea, high-rise buildings (urban area) and mountain and hills areas (Sanjay Gandhi National Park located in the northern part of Mumbai).
Lokanadham, B., Gupta, K. and Nikam, V. (2012) Characterization of Spatial and Temporal Distribution of Monsoon Rainfall over Mumbai. ISH Journal of Hydraulic Engineering, 15, 69-80. https://doi.org/10.1080/09715010.2009.10514941
Brown, B.G., Katz, R.W. and Murphy, A.H. (1984) Statistical Analysis of Climatological Data to Characterize Erosion Potential: 4.Freezing Events in Eastern Oregon/Washington. Oregon Agricultural Experiment Station Spec. Rep. No. 689, Oregon State University.
Diodato, N. and Bellocchi, G. (2007) Estimating Monthly (R)USLE Climate Input in a Mediterranean Region Using Limited Data. Journal of Hydrology, 345, 224-236. https://doi.org/10.1016/j.jhydrol.2007.08.008
Haile, A.T., Rientjes, T.H.M., Habib, E., Jetten, V. and Gebremichael, M. (2011) Rain Event Properties at the Source of the Blue Nile River. Hydrology and Earth System Sciences, 15, 1023-1034. https://doi.org/10.5194/hess-15-1023-2011
Larsen, M.L. and Teves, J.B. (2015) Identifying Individual Rain Events with a Dense Disdrometer Network. Advances in Meteorology, 2015, Article ID: 582782. https://doi.org/10.1155/2015/582782
Dunkerley, D. (2008) Rain Event Properties in Nature and Rainfall Simulation Experiments: A Comparative Review with Recommendations for Increasingly Systematic Study and Reporting. Hydrological Processes, 22, 4415-4435. https://doi.org/10.1002/hyp.7045
Adams, B.J. and Papa, F. (2000) Urban Stormwater Management Planning with Analytical Probabilistic Models. John Wiley & Sons, New York.
Nojumuddin, N.S., Yusof, F. and Yusop, Z. (2018) Determination of Minimum Inter-Event Time for Storm Characterisation in Johor, Malaysia. Journal of Flood Risk Management, 11, S687-S699. https://doi.org/10.1111/jfr3.12242
Medina-Cobo, M.T., Garcia-Marin, A.P., Estevez, J. and Ayuso-Munoz, J.L. (2016) The Identification of an Appropriate Minimum Inter-Event Time (MIT) Based on the Multifractal Characterization of Rainfall Data Series. Hydrological Processes, 30, 3507-3517. https://doi.org/10.1002/hyp.10875
Hanel, M. and Máca, P. (2014) Spatial Variability and Interdependence of Rain Event Characteristics in the Czech Republic. Hydrological Processes, 28, 2929-2944.
Joo, J., Lee, J., Kim, J.H., Jun, H. and Jo, D. (2014) Inter-Event Time Definition Setting Procedure for Urban Drainage Systems. Water, 6, 45-58. https://doi.org/10.3390/w6010045
Balistrocchi, M. and Bacchi, B. (2011) Modelling the Statistical Dependence of Rainfall Event Variables by a Trivariate Copula Function. Hydrology and Earth System Sciences Discussions, 8, 429-481. https://doi.org/10.5194/hessd-8-429-2011
Gyasi-Agyei, Y. and Melching, C.S. (2012) Modelling the Dependence and Internal Structure of Storm Events for Continuous Rainfall Simulation. Journal of Hydrology, 464, 249-261. https://doi.org/10.1016/j.jhydrol.2012.07.014
Shamsudin, S., Dan’azumi, S. and Aris, A. (2010) Effect of Storm Separation Time on a Rainfall Characteristics—A Case Study of Johor, Malaysia. European Journal of Scientific Research, 45, 162-167.
Chin, R.J., Lai, S.H., Chang, K.B., Othman, F. and Jaafar, W.Z.W. (2016) Analysis of Rainfall Events over Peninsular Malaysia. Weather, 71, 118-123. https://doi.org/10.1002/wea.2723
Dunkerley, D. (2008) Identifying Individual Rain Events from Pluviograph Records: A Review with Analysis of Data from an Australian Dryland Site. Hydrological Processes, 22, 5024-5036. https://doi.org/10.1002/hyp.7122
Saikranthi, K., Rao, T.N., Rajeevan, M. and Bhaskara Rao, S.V. (2013) Identification and Validation of Homogeneous Rainfall Zones in India Using Correlation Analysis. Journal of Hydrometeorology, 14, 304-317. https://doi.org/10.1175/JHM-D-12-071.1
Sinha, P., Mohanty, U.C., Kar, S.C., Dash, S.K., Robertson, A.W. and Tippett, M.K. (2013) Seasonal Prediction of the Indian Summer Monsoon Rainfall Using Canonical Correlation Analysis of the NCMRWF Global Model Products. International Journal of Climatology, 33, 1601-1614. https://doi.org/10.1002/joc.3536
Nair, A., Mohanty, U.C. and Acharya, N. (2013) Monthly Prediction of Rainfall over India and Its Homogeneous Zones during Monsoon Season: A Supervised Principal Component Regression Approach on General Circulation Model Products. Theoretical and Applied Climatology, 111, 327-339. https://doi.org/10.1007/s00704-012-0660-8
Ahuja, S. and Dhanya, C.T. (2012) Regionalization of Rainfall Using RCDA Cluster Ensemble Algorithm in India. Journal of Software Engineering and Applications, 5, 568. https://doi.org/10.4236/jsea.2012.58065
Bharath, R. and Srinivas, V.V. (2015) Regionalization of Extreme Rainfall in India. International Journal of Climatology, 35, 1142-1156. https://doi.org/10.1002/joc.4044
Saha, M., Mitra, P. and Nanjundiah, R.S. (2017) Deep Learning for Predicting the Monsoon over the Homogeneous Region of India. Journal of Earth System Science, 126, 54. https://doi.org/10.1007/s12040-017-0838-7
Kakade, S.B. and Kulkarni, A. (2017) Seasonal Prediction of Summer Monsoon Rainfall over Cluster Regions of India. Journal of Earth System Science, 126, 34. https://doi.org/10.1007/s12040-017-0811-5
Dilmi, M.D., Mallet, C., Barthès, L. and Chazottes, A. (2017) Data-Driven Clustering of Rain Events: Microphysics Information Derived from Macro-Scale Observations. Atmospheric Measurement Techniques, 10, 1557-1574. https://doi.org/10.5194/amt-10-1557-2017
Manaan, A., Chaudhary, S., Dhanya, C.T. and Swamy, A.K. (2017) Regionalization of Rainfall Characteristics in India Incorporating Climatic Variables and Using Self-Organizing Maps. ISH Journal of Hydraulic Engineering, 24, 147-156.
Sherly, M.A., Karmakar, S., Chan, T. and Rau, C. (2015) Design Rainfall Framework Using Multivariate Parametric-Nonparametric Approach. Journal of Hydrologic Engineering, 21, Article ID: 04015049. https://doi.org/10.1061/(ASCE)HE.1943-5584.0001256
Sen, S., Vittal, H., Singh, T., Singh, J. and Karmakar, S. (2013) At-Site Design Rainfall Estimation with a Diagnostic Check for Nonstationarity: An Application to Mumbai Rainfall Datasets. Proceedings of Hydro, Madras, 4-6 December 2013.
Nayak, M.A. and Ghosh, S. (2013) Prediction of Extreme Rainfall Event Using Weather Pattern Recognition and Support Vector Machine Classifier. Theoretical and Applied Climatology, 114, 583-603. https://doi.org/10.1007/s00704-013-0867-3
Singh, J., Sekharan, S., Karmakar, S., Ghosh, S., Zope, P.E. and Eldho, T.I. (2017) Spatio-Temporal Analysis of Sub-Hourly Rainfall over Mumbai, India: Is Statistical Forecasting Futile? Journal of Earth System Science, 126, 38. https://doi.org/10.1007/s12040-017-0817-z
Estevez, J., Gavilan, P., García-Marin, A.P. and Zardi, D. (2015) Detection of Spurious Precipitation Signals from Automatic Weather Stations in Irrigated Areas. International Journal of Climatology, 35, 1556-1568. https://doi.org/10.1002/joc.4076
Restrepo-Posada, P.J. and Eagleson, P.S. (1982) Identification of Independent Rainstorms. Journal of Hydrology, 55, 303-319. https://doi.org/10.1016/0022-1694(82)90136-6
Lowe, R., Madsen, H. and McSharry, P. (2016) Objective Classification of Rainfall in Northern Europe for the Online Operation of Urban Water Systems Based on Clustering Techniques. Water, 8, 87. https://doi.org/10.3390/w8030087
He, Z., Zhao, W., Liu, H. and Chang, X. (2012) The Response of Soil Moisture to Rainfall Event Size in Subalpine Grassland and Meadows in a Semi-Arid Mountain Range: A Case Study in Northwestern China’s Qilian Mountains. Journal of Hydrology, 420, 183-190. https://doi.org/10.1016/j.jhydrol.2011.11.056
Huang, J., Zhang, J., Zhang, Z. and Xu, C.Y. (2012) Spatial and Temporal Variations in Rainfall Erosivity during 1960-2005 in the Yangtze River Basin. Stochastic Environmental Research and Risk Assessment, 27, 337-351. https://doi.org/10.1007/s00477-012-0607-8
Meusburger, K., Steel, A., Panagos, P., Montanarella, L. and Alewell, C. (2012) Spatial and Temporal Variability of Rainfall Erosivity Factor for Switzerland. Hydrology and Earth System Sciences, 16, 167-177. https://doi.org/10.5194/hess-16-167-2012
Ran, Q., Su, D., Li, P. and He, Z. (2012) Experimental Study of the Impact of Rainfall Characteristics on Runoff Generation and Soil Erosion. Journal of Hydrology, 424-425, 99-111. https://doi.org/10.1016/j.jhydrol.2011.12.035
Kohonen, T. (1995) Self-Organizing Maps. Third Edition, Springer, Berlin. https://doi.org/10.1007/978-3-642-97610-0
Kohonen, T. (2013) Essentials of the Self-Organizing Map. Neural Networks, 37, 52-65. https://doi.org/10.1016/j.neunet.2012.09.018
Vesanto, J., Himberg, J., Alhoniemi, E. and Parhankagas, J. (2000) SOM Toolbox for Matlab 5, Report A57. http://www.cis.hut.fi/projects/somtoolbox/
Fincke, T., Lobo, V. and Bação, F. (2018) Visualizing Self-Organizing Maps with GIS. GI Days. https://www.researchgate.net/profile/Fernando_Bacao/publication/228660313_Visualizing_self-organizing_maps_with_GIS/links/0fcfd50a2730443654000000.pdf
Lourenço, F.C., Lobo, V.S. and Bação, F.L. (2014) Exploratory Geospatial Data Analysis Using Self-Organizing Maps. Case Study of Portuguese Mainland Regions. https://www.researchgate.net/publication/237226357
Polzlbauer, G., Dittenbach, M. and Rauber, A. (2006) Advanced Visualization of Self-Organizing Maps with Vector Fields. Neural Networks, 19, 911-922. https://doi.org/10.1016/j.neunet.2006.05.013
Tan, P.N., Steinbach, M. and Kumar, V. (2006) Introduction to Data Mining. Pearson Education, Addison Wesley, Boston, 769.
Paul, S., Ghosh, S., Mathew, M., Devanand, A., Karmakar, S. and Niyogi, D. (2018) Increased Spatial Variability and Intensification of Extreme Monsoon Rainfall Due to Urbanization. Scientific Reports, 8, Article No. 3918. https://doi.org/10.1038/s41598-018-22322-9