Planetary Variables

Planetary Variables are analysis-ready data feeds from Planet that measure changing conditions on the Earth's land surface, so that users can monitor water, temperature and vegetation without acquiring and processing raw satellite imagery themselves. Planet's remote-sensing scientists fuse observations from Planet's own satellites and from public missions across the spectrum (optical, radar and passive microwave) into consistent, gap-free measurements:

• Soil Water Content: near-daily soil moisture at 1 km resolution with global coverage, derived from the SMAP, AMSR2 and AMSR-E passive-microwave radiometers, with an archive back to 2002.
• Land Surface Temperature: twice-daily global measurements at 1 km from AMSR2 and AMSR-E microwave observations, available regardless of cloud cover.
• Crop Biomass: a daily, cloud-free relative biomass index for agricultural fields at 10 m (from 2019) and 3 m (from 2024), fusing Sentinel-1 radar with Sentinel-2 and PlanetScope optical imagery.

Users subscribe to their areas of interest through Planet's Subscriptions API, the Planet SDK for Python or its command-line tools, and receive GeoTIFF rasters and time series delivered to Amazon S3, Google Cloud Storage, Microsoft Azure or Oracle Cloud, or hosted on the Planet Insights Platform. Planet publishes a technical specification, validation material and peer-reviewed methodology for each variable.

Applications include irrigation and field-operation planning, crop growth and stress monitoring, variable-rate input planning, yield modelling, drought and water-resource monitoring, and natural-disaster risk assessment. Named users include AXA Climate and Swiss Re, which build parametric drought insurance on Soil Water Content, the Dutch Water Authorities for managing water distribution, and agricultural companies BASF and Disagro for crop monitoring.