Deep neural network enhanced global tropospheric zenith delay model

DOI

With the growing use of airborne platforms in Earth observation, accurate tropospheric delay corrections across various altitudes have become essential. Most existing tropospheric delay models are referenced to the Earth’s surface and rely on analytical closed-form vertical adjustments to approximate delays at user heights. However, these analytical models often fail to capture the complex vertical variations in atmospheric conditions.

To address this limitation, we developed a novel approach leveraging deep neural networks (DNN) to reconstruct global three-dimensional zenith hydrostatic delay (ZHD) and zenith wet delay (ZWD) derived from numerical weather models (NWM). Using the ERA5 pressure-level product (Hersbach et al., 2020) for model training, the DNN refines predictions by correcting the residuals of an analytical third-order exponential model (EXP3). This hybrid method takes advantage of the non-linear fitting capabilities of DNN, significantly enhancing the accuracy of vertical tropospheric delay corrections up to 14 km above the Earth’s surface. The model achieves an average precision of 0.4 mm for ZHD and 0.8 mm for ZWD, reducing root-mean-square (RMS) errors by 63% and 36%, respectively, compared to EXP3.

This dataset includes the EXP3 model, structured on a 1° × 1° global grid at four synoptic times daily (00:00, 06:00, 12:00, and 18:00 UTC) for the period 2019–2022. Additionally, it provides the corresponding DNN model to correct errors in the EXP3 predictions. It is important to note that the model is designed for altitudes ranging from the Earth’s surface up to 14 km.

Identifier
DOI https://doi.org/10.5880/GFZ.1.1.2024.001
Related Identifier IsSupplementTo https://doi.org/10.1029/2024GL111404
Related Identifier Cites https://doi.org/10.1002/qj.3803
Metadata Access http://doidb.wdc-terra.org/oaip/oai?verb=GetRecord&metadataPrefix=oai_datacite&identifier=oai:doidb.wdc-terra.org:8024
Provenance
Creator Yuan, Peng ORCID logo; Balidakis, Kyriakos ORCID logo; Wang, Jungang ORCID logo; Xia, Pengfei ORCID logo; Wang, Jian ORCID logo; Zhang, Mingyuan ORCID logo; Jiang, Weiping ORCID logo; Schuh, Harald ORCID logo; Wickert, Jens ORCID logo; Deng, Zhiguo ORCID logo
Publisher GFZ Data Services
Contributor Yuan, Peng; Deng, Zhiguo
Publication Year 2024
Funding Reference Bundesministerium für Umwelt, Naturschutz, nukleare Sicherheit und Verbraucherschutz http://dx.doi.org/10.13039/501100013549 Crossref Funder ID 67KI32002C EKAPEx; Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 Crossref Funder ID SFB 1464, No. 434617780 TerraQ; Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 Crossref Funder ID FOR 5456, No. 490990195 COCAT; State Key Laboratory of Geo-Information Engineering http://dx.doi.org/10.13039/501100011354 Crossref Funder ID SKLGIE2024-M-1-1
Rights CC BY 4.0; http://creativecommons.org/licenses/by/4.0/
OpenAccess true
Contact Yuan, Peng (GFZ German Research Centre for Geosciences, Potsdam, Germany)
Representation
Resource Type Model
Discipline Geosciences
Spatial Coverage (-180.000W, -90.000S, 180.000E, 90.000N); Global coverage at synoptic hours in 2019-2021
Temporal Coverage Begin 2019-01-01T00:00:00Z
Temporal Coverage End 2021-12-31T18:00:00Z