Evaluation of IMERG and ERA5 precipitation products over the Mongolian Plateau

Abstract

Precipitation is an important component of the hydrological cycle and has significant impact on ecological environment and social development, especially in arid areas where water resources are scarce. As a typical arid and semi-arid region, the Mongolian Plateau is ecologically fragile and highly sensitive to climate change. Reliable global precipitation data is urgently needed for the sustainable development over this gauge-deficient region. With high-quality estimates, fine spatiotemporal resolutions, and wide coverage, the state-of-the-art Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG) and European Center for Medium-range Weather Forecasts Reanalysis 5 (ERA5) have great potential for regional climatic, hydrological, and ecological applications. However, how they perform has not been well investigated on the Mongolian Plateau. Therefore, this study evaluated the performance of three IMERG V06 datasets (ER, LR and FR), two ERA5 products (ERA5-HRES and ERA5-Land), and their predecessors (TMPA-3B42 and ERA-Interim) over the region across 2001–2018. The results showed that all products broadly characterized seasonal precipitation cycles and spatial patterns, but only the three reanalysis products, IMERG FR and TMPA-3B42 could capture interannual and decadal variability. When describing daily precipitation, dataset performances ranked ERA5-Land > ERA5-HRES > ERA-Interim > IMERG FR > IMERG LR > IMERG ER > TMPA-3B42. All products showed deficiencies in overestimating weak precipitation and underestimating high-intensity precipitation. Besides, products performed best in agricultural lands and forests along the northern and south-eastern edges, followed by urban areas and grasslands closer to the center, and worst in the sparse vegetation and bare areas of the south-west. Due to a negative effect of topographic complexity, IMERG showed poor detection capabilities in forests. Accordingly, this research currently supports the applicability of reanalysis ERA5 data over the arid, topographically complex Mongolian Plateau, which can inform regional applications with different requirements.

Evaluating the Representations of Atmospheric Rivers and Their Associated Precipitation in Reanalyses With Satellite Observations

“…However, IMERG is produced by merging the precipitation estimates with highest quality passive microwave sensors and infrared sensors. It thus can be regarded as the state‐of‐the‐art observational precipitation product (Li et al., 2023; W. Ma, Chen, & Guan, 2020; Watters et al., 2021; Xin et al., 2022). Compared to IMERG, it has been well known that models have trouble simulating the precipitation realistically (D. Chen et al., 2021; Christopoulos & Schneider, 2021; Frei et al., 2003; H. Kim et al., 2021).…”

“…It thus can be regarded as the state-of-the-art observational precipitation product (Li et al, 2023;W. Ma, Chen, & Guan, 2020;Watters et al, 2021;Xin et al, 2022). Compared to IMERG, it has been well known that models have trouble simulating the precipitation realistically (D. Chen et al, 2021;Christopoulos & Schneider, 2021;Frei et al, 2003;.…”

Climatology of icing conditions over Colombia based on ERA5 reanalysis and in situ observations

“…The overestimation could also be related to the fact that ERA5 overestimates precipitation over high mountain ranges such as the Andes and Himalayas (Hassler & Lauer, 2021). Other studies have reported that ERA5 tends to overestimate precipitation and incorrectly identify numerous non‐precipitation events in various regions, including Austria (Sharifi et al, 2019), southern China (Gao et al, 2020), North America (Tarek et al, 2020), Iran (Yazdandoost et al, 2020), the Tibetan Plateau (Zhang et al, 2022) and the Mongolian Plateau (Xin et al, 2022). This is likely due to the limitations in the representation of cumulus parameterizations in high‐gradient mountain slopes (Zhang et al, 2022).…”

Hydrological Response to Vegetation Changes in the Yellow River Basin

“…Model-based meteorological products have undergone rapid development over the past few decades (Muñoz-Sabater et al, 2021). The state-of-the-art model-based dataset, ERA5-land, has been verified to have a good performance over subregions of temperate monsoon climate and temperate continental climate in China, which is the major type of the YRB (Xin et al, 2022;Xu et al, 2022). The use of ERA5-land enables a continuous and accurate representation of spatial meteorological heterogeneity, as well as the provision of additional surface indicators such as evaporation, which allows for the distributed Budyko analysis to present the runoff analysis results that are comparable to those obtained in physical models.…”