Comparative Analysis of TMPA and IMERG Precipitation Datasets in the Arid Environment of El-Qaa Plain, Sinai

Abstract

The replenishment of aquifers depends mainly on precipitation rates, which is of vital importance for determining water budgets in arid and semi-arid regions. El-Qaa Plain in the Sinai Peninsula is a region that experiences constant population growth. This study compares the performance of two sets of satellite-based data of precipitation and in situ rainfall measurements. The dates selected refer to rainfall events between 2015 and 2018. For this purpose, 0.1° and 0.25° spatial resolution TMPA (Tropical Rainfall Measurement Mission Multi-satellite Precipitation Analysis) and IMERG (Integrated Multi-satellite Retrievals for Global Precipitation Measurement) data were retrieved and analyzed, employing appropriate statistical metrics. The best-performing data set was determined as the data source capable to most accurately bridge gaps in the limited rain gauge records, embracing both frequent light-intensity rain events and more rare heavy-intensity events. With light-intensity events, the corresponding satellite-based data sets differ the least and correlate more, while the greatest differences and weakest correlations are noted for the heavy-intensity events. The satellite-based records best match those of the rain gauges during light-intensity events, when compared to the heaviest ones. IMERG data exhibit a superior performance than TMPA in all rainfall intensities.

Optimization of Rain Gauge Networks for Arid Regions Based on Remote Sensing Data

“…Bearing in mind the above, the suitability of IMERG precipitation datasets was investigated over El-Qaa Plain in the preceding research [14] where the frequency of light events is high. The results of that study were encouraging, as IMERG datasets from the light-intensity events were highly correlated with the in-situ measurements.…”

“…Over the same region, Morsy et al [14] contrasted TRMM (Tropical Rainfall Measurement Mission) and IMERG satellite precipitation products, on the one hand, and against ground rain gauges, on the other hand. They concluded that IMERG estimations perform better than TRMM.…”

“…Each IMERG scene consists of a daily composite of half-hourly scenes obtained from NASA Mirador's official website (Figure 3). The final run of the GPM (IMERG) selection criteria was presented in a companion paper [14].…”

“…Two data sets were chosen in the current analysis to optimize the coarse rain gauge network. The final run of GPM (IMERG), which performed better in a previous comparative study [14], was used, along with 90 × 90 Shuttle Radar Topography Mission (SRTM) elevation data. This was achieved by the use of statistical metrics such as k-means clustering, normal error kriging, and the Empirical Cumulative Distribution Function (ECDF).…”

Performance Evaluation and Comparison of Satellite-Derived Rainfall Datasets over the Ziway Lake Basin, Ethiopia

“…In general, CHIRPS showed slightly better performance than the other three IMERG runs for monthly and seasonal time scales. Previous studies have already confirmed the superiority of CHIRPS than IMERG runs for different parts of the world [40,[71][72][73], including Ethiopia [31,47,49]. For example, Wedajo et al [47] reported better rainfall estimation by CHIRPS compared with IMERG and TAMSAT3 and 3B42/3 products for the Dhidhessa River Basin, Ethiopia.…”