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Highlights • Comparison of IMD and TRMM-TMPA, CMORPH, PERSIANN, and MSWEP precipitation data. • Mann–Kendall (MK), modified Mann–Kendall (MMK), and Sen's Slope for trend analysis. • PERSIANN precipitation data has shown better trend result with the IMD data. Abstract This study compares the precipitation trend from the gridded rain gauge data collected by India Meteorological Department (IMD) and Multisatellite High Resolution Precipitation Products (HRPPs) including Tropical Rainfall Measurement Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) version 7, Climate Prediction Center Morphing (CMORPH) version 1.0, Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), and Multi-Source Weighted-Ensemble Precipitation (MSWEP) version 1.1 for the river basins of India. The IMD and HRPPs are of the same spatial resolution (0.25° × 0.25°) and extend from 1998 to 2015. The gridded precipitation datasets are compared for 25 river basins of India. TRMM, CMORPH, PERSIANN, and MSWEP datasets accuracy for the river basins are assessed by comparison with IMD using root mean square error (RMSE) and correlation coefficient (CC) methods. The Mann–Kendall (MK) and modified Mann–Kendall (MMK) tests are applied for analyzing the data trend, and the change is detected by Sen's Slope using all datasets for annual and seasonal time periods. Variation in precipitation is high (>20%) in the northern part of India in all datasets. All these basins located at the elevations above 2000 m. The annual and monsoon trend pattern for TMPA, CMORPH, PERSIANN, and MSWEP matched with IMD data in the north, northwest, and central part in 1–2, 22–25, and parts of 3, 12, and 21 river basins (1998–2015). The calculated results implied that the TMPA precipitation product (in terms of accuracy) and PERSIANN (in terms of annual and monsoon trend) show a better agreement with IMD and they can be used in climate studies and hydrological simulation in locations/river basins where the number of rain gauges is not adequate to quantify the spatial variability of precipitation. [ABSTRACT FROM AUTHOR]

Highlights • Innovative trend analysis (ITA) and Mann-Kendall (MK) determine average trend. • Double-ITA, Triple-ITA, and partial MK are proposed for stability test of trends. • ITA should be used together D-ITA or T-ITA for better trend analysis. • MK should be used together partial MK for better trend analysis. • Comparisons of ITA, D-ITA, T-ITA, classical MK, and partial MK are presented. Abstract The climate change is an important event that affects hydrological, agricultural and water resources planning variables, and therefore, the hydrologists and meteorologists frequently try to identify trend possibilities especially in rainfall, runoff and temperature time series. For this purpose, the classical Mann-Kendall (MK), Spearman's rho (SR), Sen's slope, and linear regression approaches are applied frequently in the literature. Recently, innovative trend analysis (ITA) provides visual inspection and identification of categorical trends, which is one of the main concerns in this paper. On the basis of ITA methodology, several improvements namely double-ITA (D-ITA) and triple-ITA (T-ITA) procedures are suggested using with simple ITA together. These methods are attractive for the trend stability assessment by comparing partial trend components during different sub-periods of a given record series. Furthermore, partial MK test approach is proposed in this paper for the same purpose. These procedures and approach are applied to a set of annual rainfall records at many stations in different regions of Turkey. As a result, the comparison of the suggested methods based on partial sub-series of the same time series helps to improve trend detection with stability identification. [ABSTRACT FROM AUTHOR]

Summary The Mahanadi river basin, a major river basin in eastern India, is expected to be the worst affected river basins in India in terms of the increase in intensity of floods due to climate change. The last decade has already seen five high floods occurring in the Mahanadi basin. Are these recent high floods an indication that Mahanadi floods are already getting worse? If so, is it due to an increase in extreme rainfalls over the basin? To answer these, we analyse the trends of peak discharge at the mouth of the delta at Naraj gauging site (the flow which is responsible for floods in the delta of Mahanadi basin) and peak releases from Hirakud dam in Mahanadi basin. Subsequently, grid based analysis of extreme rainfall is carried out for the entire Mahanadi basin to analyse the spatially varied extreme rainfall trends. Also, a region based (upper and middle regions of Mahanadi basin) analysis of extreme rainfall is carried out using daily mean areal rainfall. The trends of extreme rainfalls are analysed in relation to the trends of peak floods. The entire analysis pertains to post-Hirakud dam construction period. The analysis reveals that the recent incidences of high floods in Mahanadi basin is due to an increase in extreme rainfall in the middle reaches of the basin. [ABSTRACT FROM AUTHOR]