Spatio‐temporal evaluation of gridded precipitation products for the high‐altitude Indus basin

Abstract

The high-altitude Indus basin is one of the most complex and inadequately explored mountain terrains in the World, where reliable observations of precipitation are highly lacking. Therefore, spatially distributed precipitation products developed at global/regional scale are often used in several scientific disciplines. However, large uncertainties in precipitation estimates of such precipitation data sets often lead to suboptimal outcomes. In this study, performance of 27 widely used gridded precipitation products belonging to three different categories of gauge-based, reanalysis and merged products is evaluated with respect to high-quality reference climatologies of mean monthly precipitation. Widely used statistical measures and quantitative analysis techniques are used to analyse the spatial patterns and quantitative distribution of mean monthly, seasonal and annual precipitation at sub-regional scale.Mean annual precipitation estimates of the gridded data sets are cross validated with the corresponding adjusted streamflows using Turc-Budyko nondimensional analysis. Results reveal poor to moderately good performance of the gridded data sets. Marked differences in spatiotemporal and quantitative distribution of precipitation are found among the data sets. All data sets are consistent in their patterns showing negative or dry bias in wet areas and

Contrasting Fate of Western Third Pole's Water Resources Under 21st Century Climate Change

“…In the several previous studies (Tables S1 and S2 in Supporting Information S1), the discrepancies in runoff composition can be largely explained by the varying magnitudes of precipitation inputs (e.g., ranging between 311 and 832 mm in the UI and 326-942 mm in the USD in annual means). Uncertainties resulting from the challenges/issues in precipitation inputs for model calibration and validation have been widely recognized and assessed in the TP region (Dahri et al, 2021;Lutz et al, 2014Lutz et al, , 2016Pellicciotti et al, 2012;Ragettli et al, 2013;Sun & Su, 2020;Wortmann et al, 2018). Therefore, developing a homogenized and representative climate data archive is urgently needed for a better understanding or assessment or quantification of current and future water availability in the TP.…”

General overestimation of ERA5 precipitation in flow simulations for High Mountain Asia basins

“…compared the precipitation gradient characteristics obtained from ERA5 and gauge observations in the monsoon-dominated and westerlies-dominated HMA basins, suggesting that ERA precipitation can capture the pattern of precipitation gradient in most basins. Dahri et al (2021b) evaluated 27 gridded precipitation products in the high-altitude Indus, and suggested that among all the products, ERA5 exhibited the most acceptable performance for all sub-regions of the upper Indus. However, existing studies about ERA5 precipitation estimates are mostly focused on the spatiotemporal performances in the TP based on limited gauge observations which are mostly located in the eastern TP region.…”

Knowledge Priorities on Climate Change and Water in the Upper Indus Basin: A Horizon Scanning Exercise to Identify the Top 100 Research Questions in Social and Natural Sciences

“…Additionally, exchanging data between the four UIB member countries is complicated (Qamar et al., 2019; Salzmann et al., 2014). Efforts to overcome the paucity of direct observations in the UIB include using gridded observational datasets (from sources such as gauge and satellite measurements) and reanalysis, which have various levels of accuracy and also can give contradictory results (Dahri, Ludwig, Moors, & et al., 2021; H. Li et al., 2018; Palazzi et al., 2013). The questions below reflect attempts to improve data collection and monitoring across the UIB. …”