Dataset Title
Daily Global Sea Surface Ageostrophic Current Dataset from 1993–2023 via Physics-Informed Deep Learning
1. Dataset Overview
This dataset provides a daily, high-resolution (0.25°) reconstruction of global sea surface circulation spanning a 31-year period from January 1, 1993, to December 31, 2023. The reconstruction accurately models ocean dynamics by explicitly accounting for key physical drivers, including wind stress, non-linear effects, and the Coriolis force. It separates the total flow field into geostrophic, Ekman, and non-linear advective components, providing a comprehensive view of global surface currents.
2. Data Format and CF Standard Compliance
Format: NetCDF-4 Classic (netcdf4_classic)
Standard Compliance: The NetCDF files have been formatted to comply with the Climate and Forecast (CF) Metadata Conventions (CF-1.8). All spatial and temporal dimensions, variable names, units, and missing values conform to standard conventions to ensure seamless integration with standard Earth science software (e.g., Panoply, CDO, Python xarray, MATLAB).
3. File Naming Conventions and Directory Structure
The dataset contains daily files spanning 31 years. The dataset is systematically organized into subdirectories by year and month. Each daily file follows a standard path structure:
Structure: [YYYY]/[MM]/[YYYY]_[MM]_[DD].nc
Examples:
1993/01/1993_01_01.nc
1993/01/1993_01_02.nc
4. Variables, Units, and Missing Values
The data variables are defined on a 1440 (longitude) × 720 (latitude) grid. Missing data points (e.g., over landmasses) are designated with a standard _FillValue of NaN.
Variable Name
Long Name / Definition
Units
Dimensions
Data Type
lon
Longitude
degrees_east
lon (1440)
double
lat
Latitude
degrees_north
lat (720)
double
time
Time
days since 1993-01-01
time (1)
double
sla
Sea Level Anomaly
m
lat, lon
double
uadv
Zonal (u) component of the nonlinear advective term
m/s
lat, lon
double
vadv
Meridional (v) component of the nonlinear advective term
m/s
lat, lon
double
utotal
Zonal (u) component of the total flow field (ugeo+uekman+uadv)
m/s
lat, lon
double
vtotal
Meridional (v) component of the total flow field (vgeo+vekman+vadv)
m/s
lat, lon
double
resu
Residual of the zonal (u) momentum
m/s2
lat, lon
double
resv
Residual of the meridional (v) momentum
m/s2
lat, lon
double
ugeo
Zonal (u) component of the geostrophic current
m/s
lat, lon
double
vgeo
Meridional (v) component of the geostrophic current
m/s
lat, lon
double
uekman
Zonal (u) component of the surface (0 m) Ekman current
m/s
lat, lon
double
vekman
Meridional (v) component of the surface (0 m) Ekman current
m/s
lat, lon
double
Missing Data handling: All un-computable grid points or land areas utilize a standard missing value indicator (_FillValue = NaN).
5. Global Metadata
Each NetCDF file contains global attributes to track provenance and creation details:
creation_date: Automatically generated date of file creation.
author: Zhongya Cai and Guangxi Cui et al., University of Macao.
Conventions: CF-1.8
6. Data Access and Download Method
Due to the large volume of the full 31-year dataset (exceeding 500 GB), which surpasses standard repository upload limits, we have uploaded a representative sample data file alongside the README.txt directly to this Zenodo repository.
To access and download the complete dataset, all individual files are hosted on a high-speed remote S3 server.
Base URL:
s3.jn1.is.shanhe.com
Users can retrieve specific files by appending the standardized directory structure to the Base URL:
[Base_URL]/[YYYY]/[MM]/[YYYY]_[MM]_[DD].nc
Download Examples:
s3.jn1.is.shanhe.com
s3.jn1.is.shanhe.com
Please refer to the attached README.txt file on this page for a comprehensive list of direct download links for every individual file in the 31-year series.