Cloud Microphysics (CMIC)
Contents:
- Goal of the Cloud Microphysics product
- Cloud Physical Product algorithm summary
- Cloud Physical Product outputs
Goal of the Cloud Microphysics product
The Goal of the Cloud Microphysics (cmic) parameters is to give a more detailed insight into micro-physical conditions of clouds. This means the thermodynamic phase of the cloud particles at the upper part of the cloud and the vertical integrated liquid water path. In addition to these also other cloud micro-physical parameters are retrieved. These additional parameters are made available as they may be of interest to some users. But they are not validated and are not part of the official product.
Cloud Microphysics algorithm summary
A central step within the cmic retrieval is an iterative process wherein the convergence of cloud optical thickness and cloud particle size is tested. First pre-calculated Look-Up Tables (lut) for ice-phase are used and if this does not succeed liquid water luts are used. The finally used lut-set leads directly to the cloud phase product. In case of water-clouds, the vertically integrated liquid water content is derived from an analytic relation, using the following auxiliary data:
- Sun and satellite angles
- Surface albedo
- Surface emissivity
- Surface temperature
- Water vapour path
Cloud Microphysics output
Main output
There are two official products of Cloud Microphysics:
- Liquid Water Path, in kg/m²
- Cloud Phase, in 2 classes, see below
| Value | Class name |
|---|---|
| 1 | Cloud phase: liquid |
| 2 | Cloud phase: ice |
| 255 | Unprocessed / No data |
Additional output
There are five additonal products of Cloud Microphysics:
- Ice Water Path, in kg/m²
- Cloud water path (i.e. both liquid and ice water path) in kg/m²
- Cloud Optical Thickness, a dimensionless quantity from 0 an up
- Cloud Effective Radius, in meters
- Extended cloud phase, in 8 categories
In addition there are six data sets for quality and processing information:
- Error estimates for: cloud water path, cloud optical thickness and cloud effective radius
- Three quality/condition flags