Study on X-band Dual Polarization Radar Echo Attenuation Correction Based on Transformer Architecture

Expand
  • 1. College of Atmospheric SciencesChengdu University of Information TechnologyChengdu 610225SichuanChina
    2. State Key Laboratory of Disaster Weather Science and TechnologyCAMSBeijing 100081China
    3. College of Electronic EngineeringChengdu University of Information TechnologyChengdu 610225SichuanChina
    4. Hebei Provincial Meteorological Disaster Prevention and Environmental Meteorology CenterShijiazhuang 050021HebeiChina

Online published: 2025-10-20

Abstract

Attenuation effects in X-band weather radar significantly constrain its detection accuracy. Traditional attenuation correction methods typically rely on empirical formulas with limited parameters and poor generalization capabilityleading to significant uncertainty in the correction results. In recent yearsdeep learning algo‐ rithm with powerful nonlinear fitting capacity has emerged as a promising technical approach to overcome the limitations of conventional methods. Based on the Transformer's underlying frameworkthis study develops an X-band radar attenuation correction architecture named as XCORnet. Utilizing the observational data from the up‐ graded polarimetric S-band Next Generation Weather RadarCINRAD/SADat Beijing Daxing in 2023-2024 flood season as truththe horizontal reflectivityZHand differential reflectivityZDRmeasurements in corresponding range bins from the Beijing Fangshan X-band dual-polarization radarXPOLare spatially and tempo‐ rally matched. These matched XPOL observations of ZHZDR along with specific differential phaseKDPare incorporated to construct the AI training datasetin which 2642624 samples for ZH and 2605583 samples for ZDRrespectively. The dataset is partitioned with 80% for training and 20% for testing. Within the XCORnet frame‐ workthe models with KDP as the primary feature input for ZH and ZDR attenuation correction are trainedrespectively. And thentwo XCORnet-based models are evaluated by means of the test set. The results demonstrate that the AI-based model outperforms traditional methods significantly. For ZH correctionthe ratio biasBIASof XPOL to SAD are from original 0. 875 to model-based correction 0. 972surpassing the empirical formula-based 0. 901. The root mean square errorRMSEare reduced from original 8. 693 to model-based 5. 811 dB with a 33. 15% improvementwhereas the empirical formula only reduced it to 6. 820 dBwith a 21. 54% improvement. For ZDR correctionthe BIAS are from original 0. 862 to model-based 1. 141outperforming the over-correction of empirical formula-based1. 273. The RMSE decreased from original 1. 679 to model-based 0. 972 dB with a 42. 10% improvement),compared to the empirical formula-based reduction only 1. 382 dBwith a 17. 69% improvement. For ZH correctionthe mean absolute errorMAEimproves from 6. 292 to 4. 222 dB with a 32. 89% improvement),whereas the empirical formula only reduces it to 5. 113 dBZwith a 18. 73% improvement. For ZDR correctionthe MAE decreases from original 1. 271 to model-based 0. 697 dBwith a 45. 16% improvement),compared to the empirical formula-based reduction only to 1. 008 dBwith a 20. 69% improvement. The MAE with model correction also showed distinct advantages over that with traditional methods. Three cases further validate the stability and generalization capability of AI-based correction.

Cite this article

ZHANG Yuankang, HU Zhiqun, ZHENG Jiafeng, WANG Lirong . Study on X-band Dual Polarization Radar Echo Attenuation Correction Based on Transformer Architecture[J]. Plateau Meteorology, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00089

Outlines

/