Monthly Global Water Cloud Thickness from GCOM-C Satellite

Water cloud optical thickness measurements are derived from the SGLI sensor on JAXA's GCOM-C satellite, launched in December 2017. The dataset provides monthly binned statistics at a 1/12-degree spatial resolution using an EQA projection. It is produced by the Japan Aerospace Exploration Agency (JAXA) to support long-term climate observations.

Use Cases

• Analyze spatial patterns of average water cloud optical thickness (AVE) to study cloud-climate feedback mechanisms.
• Investigate data reliability by comparing the number of input data (Ninput) and used data (Nused) across different geographic regions.
• Track temporal changes in cloud properties by aggregating monthly binned statistics over the satellite's operational period.
• Filter data quality using the provided quality flag (QA_flag) for robust analysis of cloud optical thickness trends.
• Assess variability in cloud thickness by examining the root-mean-square (RMS) statistic alongside minimum (MIN) and maximum (MAX) values.

Strengths

• Data is derived from a dedicated climate observation satellite (GCOM-C) with a 1150-1400 km swath for global coverage.
• Includes multiple statistical measures per bin: average, RMS, max, min, and data counts for transparency.
• Offers data at multiple temporal resolutions: 1-day, 8-day, and 1-month binned products.
• Provides a consistent EQA projection and 1/12-degree spatial resolution for global analysis.

Limitations

• Specific row count, total file size, and exact temporal coverage are not provided in the description.
• Data is spatially aggregated (binned), which reduces the native spatial detail from the original sensor measurements.
• Relies on satellite sensor retrievals for cloud optical thickness, which can contain algorithmic uncertainties.

Provenance

Source

Japan Aerospace Exploration Agency (JAXA), from the SGLI sensor onboard the GCOM-C satellite.

Collection Method

Level 3 product statistically processed from Level 1B and Level 2 satellite retrievals, binned over 1 month.

Time Range

Coverage begins after the satellite's launch on December 23, 2017; end date is not specified.

Freshness

Update frequency is not specified, but the product is at Version 3, indicating ongoing processing.

Geography

Global coverage, binned to a 1/12-degree grid.