Roychoudhury et al. (2026) MATCHA, a novel regional hydroclimate-chemical reanalysis: System description and evaluation

Identification

• Journal: Earth system science data
• Year: 2026
• Date: 2026-07-22
• Authors: Chayan Roychoudhury, Rajesh Kumar, William Y. Y. Cheng, Kirpa Ram, Naoki Mizukami, Avelino F. Arellano
• DOI: 10.5194/essd-18-5209-2026

Research Groups

• Department of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, USA
• Research Applications Laboratory, NSF National Center for Atmospheric Research, Boulder, USA
• Department of Chemistry, Indian Institute of Technology, Varanasi, India
• Department of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, USA

Short Summary

This study presents MATCHA (Model for Atmospheric Transport and Chemistry in Asia), a 17-year regional hydroclimate-chemical reanalysis for Asia at 12 km resolution. MATCHA couples WRF-Chem with CLM-SNICAR to simulate interactions between atmospheric composition and regional hydroclimate.

Objective

• Develop a high-resolution regional hydroclimate-chemical reanalysis for Asia that explicitly represents interactions between atmospheric composition and regional hydroclimate.
• Evaluate the ability of MATCHA to simulate meteorological, hydrological, and air quality parameters over High Mountain Asia (HMA).

Study Configuration

• Spatial Scale: 12 km resolution over the Asian domain (58–140°E, 4–40°N)
• Temporal Scale: 17 years (2003–2019)

Methodology and Data

• Models used:
  • Weather Research and Forecasting model with Chemistry (WRF-Chem)
  • Community Land Model (CLM) version 4.0 coupled with SNICAR snow albedo model
• Data sources:
  • Aerosol optical depth (AOD) from Moderate Resolution Imaging Spectroradiometer (MODIS)
  • Carbon monoxide (CO) profiles from Measurement of Pollution in the Troposphere (MOPITT)

Main Results

• MATCHA reproduces surface and upper-air meteorology well, with Kling-Gupta efficiencies (KGEs) of 0.65 to 1.
• Snow cover fraction seasonality is captured across major glacier regions, with a slight underestimation during snowmelt.
• Daily precipitation agrees most closely during the monsoon (KGE up to 0.6).
• MATCHA reproduces spatial and seasonal patterns of AOD and single scattering albedo (SSA) at 550 nm but overestimates summer AOD over India and Southeast Asia.

Contributions

• This study provides a comprehensive validation of the MATCHA dataset and documents error characteristics for different parameters.
• The novelty of this regional reanalysis includes coupling aerosol species with radiation and snowpack using CLM-SNICAR coupled with WRF-Chem.

Funding

• NSF National Center for Atmospheric Research (NCAR)
• University of Arizona

Citation

@article{Roychoudhury2026MATCHA,
  author = {Roychoudhury, Chayan and Kumar, Rajesh and He, Cenlin and Cheng, William Y. Y. and Ram, Kirpa and Mizukami, Naoki and Arellano, Avelino F.},
  title = {MATCHA, a novel regional hydroclimate-chemical reanalysis: System description and evaluation},
  journal = {Earth system science data},
  year = {2026},
  doi = {10.5194/essd-18-5209-2026},
  url = {https://doi.org/10.5194/essd-18-5209-2026}
}