A long-term 30-m footprint-matched gross primary productivity dataset for global flux tower sites (1984—2024)

This dataset provides a long-term, high-resolution benchmark of Gross Primary Productivity (GPP) for 324 global flux tower sites. The product is specifically designed to support terrestrial carbon cycle research, model validation, and the assessment of ecosystem responses to climate change.

1. Data Scope and Resolution

• Temporal Coverage: 1984–2024 (Daily resolution).

• Spatial Resolution: 30 meters (nominal).

• Spatial Domain: Each site-level record contains a 200 × 200 pixel domain centered on the respective flux tower coordinates.

• Site Coverage: 324 global flux tower sites.

2. File Format and Structure

• Format: NetCDF-4 (.nc).

• Naming Convention: [SiteID]_daily_30m_1984_2024.nc.

• Variables:

  • GPP: Gross Primary Productivity (Primary variable).

  • Coordinates: Longitude, Latitude, and Time.

• Encoding: GPP values are stored as 16-bit signed integers (Short) with a scale factor of 0.01. To retrieve physical values in g C m⁻² d⁻¹, users must multiply the stored integers by 0.01.

• Fill Value: -32,767 (used for missing values or non-vegetation pixels).

3. Metadata

Detailed global attributes within each file provide essential metadata, including:

• Site identifier

• IGBP vegetation type

• Creation date and processing information