BEAM Data Processors - Cloud Probability

Please note: The chapter BEAM Scientific Data Processors provides a general description for all BEAM data processors. It describes the common graphical user interface (GUI), the command-line interface and the common processing request file format.

The Cloud Probability In- and Output Parameters tab

Input product file: Select the input product file by either typing the product path into the text field or by pressing the file selection button to invoke a standard file dialog.
Output product file: Select the output product file by either typing the product path into the text field or by pressing the file selection button to invoke a standard file dialog.
Output product format: Select one of the available output product formats.
Extra log to output directory: Select whether to write an additional log file to the directory selected for the output product.

The Cloud Probability Processing Request File

The following table describes the Cloud Probability processor specific processing request file contents. For a detailed description of the processing request file concept and file specification please look at chapter Processing Request Files.

Parameter name	Description	Type	Valueset
type	Request type. Mandatory attribute of the `Request` element	String	"MER_L2_CLOUD"

Advanced configuration

The algorithm uses two different neural nets. The first for usage over land and the second for usage over the open ocean. By default every pixel which altitude is below -50m is treated as ocean.

This selection can be edited in the config files, which together with the neural nets are unpacked into a subdirectory of the user directory. The subdirectory used is .beam/cloud-probability-processor/auxdata The file cloud_config.txt specifies which configuration for the land and the ocean case are used. In the respective configuration files following properties are of interest:

The property neural_net specifies the filename of the neural net to use.
The property validExpression gives a boolean expression, which is used to select between the land and the ocean net.
First the validExpression for land is evaluated and if true the land net is used. As a second option the expression for the ocean net is evaluated. If neither of the two expressions evaluate to true, the no-data value is set.