The C2RCC processor for OLCI is known to overestimate TSM concentrations (conc_tsm band).
This has been investigated and now we want to release an update which gives much better results.
Because of the major effect, this update has on the TSM band, we wanted to inform you upfront of the release. This gives you time to prepare your processing chains, your validation setup or whatever you need to do ;-).
In the next release we will use the following equation:
conc_tsm = tsmFac * iop_btot^tsmExp
For the factor and the exponent, the following values will be set by default:
tsmFac= 1.06
tsmExp= 0.942
You can actually already test the new results with the current processor by using the equation below in the BandMath operator. The expression would look like this:
1.06 * pow(iop_btot, 0.942)
You can adapt these values to your regional requirements.
The update will probably be released early next month
I was wondering if you could explain the change from the linear TSM relationship used in C2RCC v1.0 to the power relationship used in v2.1.
I’m wondering what is the relationship between the new ‘TSMfac’ and the old ‘TSMfakBpart’, and also, the new ‘TSMexp’ and the old ‘TSMfakBwit’ if the equation has changed between v1.0 and v2.1.
The documentation seems to indicate that they were merely renamed in the new version, however, the change to the TSM relationship equation suggests they are new parameters.
But as far as I can remember, the new factors and exponents were derived from comparison with in-situ data and there is no relation to the old factors.