Dryad
Published October 11, 2024 | Version v1
Other Open

Precipitation identifiers for meteorological features combining global GPM-IMERG retrievals and ERA5 reanalysis

Authors/Creators

  • 1. University of California Los Angeles
  • 2. Indiana University Bloomington
  • 3. University of Exeter
  • 4. University of California, Davis
  • 5. Pacific Northwest National Laboratory
  • 6. University of California, Berkeley
  • 7. Lawrence Berkeley National Laboratory

Description

The data collection provides 0.25-deg., 6-hourly global feature-precipitation categories from 2001 to 2019. The data is generated by merging GPM-IMERG observational rainfall (V6 final version) and atmospheric features identified by multiple object-based algorithms. Classified precipitation identifiers include rainfall associated with atmospheric rivers (AR), frontal systems (FT), low-pressure systems (LPS), mesoscale convective systems (MCS), and their co-occurrences (overlapping areas of features at a given time). In addition to algorithm-identified features, precipitation contributed from deep convection, non-deep convection, stratiform, and drizzle are pixel-wise defined using thresholds of CPC MERGE-IR brightness temperature and GPM-IMERG rain rate. The dataset is supported by the Department of Energy and Environment (DOEE): DE-SC0023244.

Notes

Funding provided by: Department of Energy and Environment
ROR ID: https://ror.org/05d5hbz44
Award Number: DE-SC0023244

Methods

The categorization of global precipitation relies on recognizing four primary atmospheric features: atmospheric rivers (ARs), fronts (FTs), mesoscale convective systems (MCSs), and low-pressure systems (LPSs). Initially, identified atmospheric features with varying temporal and spatial resolutions are harmonized into a unified framework (6-hourly and 0.25-degree). GPM-IMERG precipitation data (0.1-degree resolution) is then coarse-grained to 0.25-degree for labeling using merged feature outputs. Additionally, precipitation attributed to deep convection, non-deep convection, stratiform, and drizzle is discerned at the pixel level using MERGE-IR brightness temperature data alongside GPM-IMERG precipitation. These classifications exclusively apply to rainy pixels not aligned with the four primary features. Rainy pixels within a specific feature boundary are considered associated with that feature object. For frontal systems represented as line segments, the line-segment masks are expanded outward by 250 km to generate two-dimensional bounded features. The identification of precipitation sources is conducted independently every 6 hours over 19 years (2001-2019). Detailed methodologies and demonstrations are accessible at https://docs.google.com/document/d/1O8NQesgyjIXv2X37wLsZ1EhgBdRKtvtPR7OYNBSBdBs/edit

Files

Global_GPM-IMERG_feature-associated_precipitation_categories.pdf

Files (1.0 MB)

Additional details

Related works

Is derived from
10.5061/dryad.v9s4mw73g (DOI)