MERIS FUB-CSIRO Coastal Water Processor - Processor Description |

### Processor Description

The MERIS FUB-CSIRO Coastal Water Processor can be invoked from the SNAP tool menu by selecting the MERIS FUB-CSIRO Coastal Water Processor command. On the command line the MERIS FUB-CSIRO Coastal Water Processor is available by means of the Graph Processing Tool `gpt` which is located in the SNAP `bin` directory. Typing `gpt FUB.Water -h` displays further information.

Selecting the MERIS FUB-CSIRO Coastal Water Processor command from the SNAP tool menu pops up the following dialog:

#### I/O Parameters Tab

##### Source Product Group

Source product: Here the user specifies the source product. The combo box presents a list of all products open in SNAP. The user may select one of these or, by clicking on the button next to the combo box, choose a product from the file system.

##### Target Product Group

Name: Used to specify the name of the target product.

Save as: Used to specify whether the target product should be saved to the file system. The combo box presents a list of available file formats. The text field or the button next to it allow to specify a target directory.

Open in SNAP: Used to specify whether the target product should be opened in SNAP. When the target product is not saved, it is opened in SNAP automatically.

##### Button Group

Run Creates the target product. The MERIS FUB-CSIRO Coastal Water Processor is actually deferred until its band data are accessed, either by writing the product to a file or by viewing its band data. When the Save as option is checked, the processing is triggered automatically.

Close Closes the dialog.

##### Menu Group

File The entries found in this menu allow to save the current processing parameters to disk and to open a saved parameter set from disk.

Help Access to this help pages and to an About dialog.

#### Processing Parameters Tab

Compute chlorophyll-a concentration band:
Whether chlorophyll-a concentration band shall be computed.

Compute yellow substances band:
Whether yellow substances band shall be computed.

Compute total suspended matter band:
Whether total suspended matter band shall be computed.

Compute water leaving reflectances and AOT bands:
Whether atmospheric correction bands shall be computed

Check whether l1_flags.SUSPECT is valid:
This is an expert parameter. Performs a check whether the l1_flags.SUSPECT shall be considered in an expression. This parameter is only considered when the expression contains the term 'and not l1_flags.SUSPECT'". This test is useful because some MERIS Level 1b scenes mark almost all pixels as suspect. If more than 50% of the pixel of an line in the scene center are marked as suspect than the suspect flag is removed from the expression.

Use valid pixel expression:
Band maths expression which defines valid pixels. If the expression is empty, all pixels will be considered as valid. The default value for the expression is
"not l1_flags.GLINT_RISK and not l1_flags.BRIGHT and not l1_flags.INVALID and not l1_flags.SUSPECT"