The MODIS Cloud Water Path indicates the amount of water in the atmosphere above a unit surface area of the earth. It is measured in grams per square meter (g/m2) and is globally retrieved for liquid and ice cloud phases. This layer is the Column Water Path retrieved using Band 7 (2.1 μm) for pixels classified as either partly cloudy from 250 m cloud mask test or 1 km cloud edges. Cloud water path forms a link between radiative and hydrological properties of the Earth’s climate system.
The MODIS Cloud Water Path layers available are: (1) the MODIS Cloud Water Path layer is the Column Water Path retrieved using Band 7 (2.1 μm); and (2) the MODIS Cloud Water Path PCL (partly cloudy) layer is the Column Water Path retrieved using Band 7 (2.1 μm) for pixels classified as either partly cloudy from 250 m cloud mask test or 1 km cloud edges.
The MODIS Cloud Water Path layers are available from both the Terra (MOD06) and Aqua (MYD06) satellites for daytime overpasses. The sensor/algorithm resolution is 1 km, imagery resolution is 1 km, and the temporal resolution is daily.
References: MODIS Atmosphere - Cloud (06_L2); NCAR|UCAR Climate Date Guide: Cloud Water Path; GES DISC: Cloud Water Path