Can GPM IMERG Capture Extreme Precipitation in North China Plain?

Abstract

Extreme precipitation events (EPE) often cause catastrophic floods accompanied by serious economic losses and casualties. The latest version (V06) of the Integrated Multi-satellite Retrievals for Global Precipitation Measurement (GPM IMERG) provides global satellite precipitation data from 2000 at a higher spatiotemporal resolution with improved quality. It is scientifically and practically important to assess the accuracy of the IMERG V06 in capturing extreme precipitation. This study evaluates the two widely used products of IMERG during 2000–2018, i.e., IMERG late run (IMERG-L) and IMERG final run (IMERG-F), in the densely populated and flood-prone North China Plain. The accuracy of the IMERG V06 is evaluated with ground measurements from rain gauge stations at multiple scales (hourly, daily, and seasonally). A novel target tracking method is introduced to extract three-dimensional (3D) extreme precipitation events, and the near-real-time uncalibrated PERSIANN-CCS (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks Cloud Classification System) and GSMAP (Global Satellite Mapping of Precipitation) satellite data are added to further evaluate IMERG’s performance during extreme precipitation. Finally, for flash flood events induced by extreme rainfall in the Hebei Province from 15 to 23 July 2016, the accuracy of capturing the event with IMERG-F and IMERG-L was verified. Results reveal that IMERG-F is better than IMERG-L at all investigated scales (hourly, daily, and seasonally), but the difference between the two products is less at higher time resolutions. Both products manifest decreased performance when capturing 3D extreme precipitation events, and comparatively, IMERG-F performs better than IMERG-L. IMERG-F exhibits a distinct discontinuity in extreme precipitation thresholds between land and ocean, which is a limitation of IMERG-F not documented in previous studies. Moreover, IMERG-L and IMERG-F are comparable at an hourly scale for some metrics, which is beyond the expectation that IMERG-F is notably better than IMERG-L. This study provides a scientific basis for the performance of satellite precipitation products and contributes to guiding users when applying global precipitation products.

Disentangling Satellite Precipitation Estimate Errors of Heavy Rainfall at the Daily and Sub-Daily Scales in the Western Mediterranean

“…Several studies have confirmed the ability of IMERG to reproduce the global spatial characteristics of precipitation fields on annual and seasonal scales [15][16][17]. However, spaceborne precipitation estimates at shorter timescales, particularly in the case of heavy rainfall events, pose more challenges, with a general tendency to underestimate [13,[17][18][19][20][21][22]. In addition, despite the large amount of work aimed at evaluating IMERG in different regions around the world, the authors of [23] reviewed a number of limitations, gaps, and suggestions provided in recent studies.…”

The Role of Changbai Mountain in an Extreme Precipitation Event in Liaoning Province, China

“…To establish the credibility of the simulation before analyzing the physical processes based on the simulation output, we use the IMERG-Final Run (V06 version) data product as rainfall observation to evaluate the WRF model's simulation performance concerning the precipitation in Liaoning Province. The IMERG products have the advantage of higher temporal (half-hourly) and spatial resolution (0.1 • ) compared to low density and uneven spatial distribution ground-based observations in the regions with complex terrain [50]. Therefore, using high-resolution satellite-derived precipitation datasets can well reflect the precipitation situation and identify rainfall characteristics in the vicinity of Changbai Mountain.…”

Rapid Extreme Tropical Precipitation and Flood Inundation Mapping Framework (RETRACE): Initial Testing for the 2021–2022 Malaysia Flood

“…IMERG is a US GPM Science Team precipitation product that applies intercalibrated estimates over various international constellations of precipitation satellites and conducts monthly surface precipitation gauge analyses to compute higher temporal (half-hourly) and spatial (0.1 • × 0.1 • ) resolutions [43,44]. These characteristics of IMERG precipitation products are advantageous in extreme studies of precipitation globally [21].…”

“…The European Space Agency's Sentinel-1 Synthetic Aperture Radar (SAR) and Sentinel-2 optical multispectral satellites are becoming popular data sources for effective flood monitoring [20]. Flood mapping using the Sentinel data are mostly conducted in northern temperate latitudes such as Europe, the UK and Canada [21]. In tropical areas, cloud cover is a prevalent issue in optical satellite imagery [22].…”