Data Questions¶

• Solar: The data is available in its original source spatial resolution.
• Meteorology: The data is available in its original source spatial resolution.

• Solar: The data was initially produced in 3-hour time increments which are averaged to provide daily values. The daily averaged values are used to calculate climatologically averaged monthly values.
• Meteorology: The data was initially produced in hourly time increments which are averaged to provided daily values. The daily averaged values are used to calculate climatologically averaged monthly values.

The POWER solar data is inferred via radiative transfer models from satellite observations.

• Solar: The data originates from NASA's GEWEX SRB 4.0-IP archive and multiple versions of NASA's CERES project.
• Meteorology: The data originates from NASA's GMAO MERRA-2 assimilation model and GEOS-IT.

Specific time periods associated with each project are listed on the Methodology: Data Sources Page.

The POWER Data Archive can be downloaded either as daily time series analysis-ready data files or as climatological monthly averaged values. For more information on the way the POWER Data Archive data is distributed to the public, see the POWER data services.

Data values in the POWER APIs are provided in units that are tailored to the selected community. If you access data directly from the Zarr datastores without using the API, the units may not adhere to community-specific standards and may need to be converted accordingly. For more information about data units served via the APIs, please visit the Parameter Dictionary.

The accuracy of both the solar and meteorology data are evaluated through direct comparisons with surface site observations. Results from these comparisons are documented in the POWER Methodology.

The POWER data, including the elevation value, represent average values over their original source spatial resolution. In complex terrain, such as mountainous regions, the averaged elevation of the grid cell can differ substantially from that of a local surface site.

For hourly data, the timestamp indicates the last day for which data was provided and includes all 24 hours of the requested date.

Collectively, the POWER Data Archive has a latency of 2-3 days for meteorological parameters and a 5-7 days for solar parameters. For the current latency status, please see the POWER Services Status Dashboard.