I am trying to convert Sentinel L1C level data (TOA Reflectance) to BOA Radiance.
To do this I was able to use Sen2Cor to transform TOA to BOA Reflectance, but I cant transform the reflectance to radiance in the generated product using the (Optical/Reflectance to Radiance).
I get the error “Please specify the solar irradiance”
If I try to convect the L1C TOA Reflectance to Radiance I have no problems.
Any ideas of what I am doing wrong or how to proceed?
The processor only considers S2 L1C, that’s why it doesn’t work with S2 L2A data.
For which application do you want BOA radiances? I Haven’t heard this before.
Thank you for your reply, that makes sense.
The reason for wanting atmospheric corrected radiance values is to be able to apply Lyzenga water column correction for seagrass mapping.
I am sorry, i forgot to ask.
is there a way of transforming reflectance to radiance in S2 L2A products?
Are you talking about water leaving radiance? Because then what you need is the atmospherically corrected data (or reflectance).
Oh, thank you about that.
I was under the impression that Lyzenga could only be applied to radiance data, but I also found a paper that used atmospherically corrected reflectance.
Thanks a lot!
Could you please share with us the name of the paper? I am also doing the same research for seagrass using sentinel-2 data and it could be handy if it is not in my list.
Thank you.
This is the paper:
Thalib, M. S., Nurdin, N., & Aris, A. (2018, June). The Ability of Lyzenga’s Algorithm for Seagrass Mapping using Sentinel-2A Imagery on Small Island, Spermonde Archipelago, Indonesia. In IOP Conference Series: Earth and Environmental Science (Vol. 165, No. 1, p. 012028). IOP Publishing.
Hope it helps!
Working with sentinel-2 and seagrass classification I am trying to find out if the L2A products provided by open hub copernicus are “ready to use” products. By saying “ready to use” I mean further corrections that must be applied to work with underwater materials. Except from water column correction which is another topic, am I satisfied with L2A products or I must apply further correction? As I have understood and already have been said, L2A products are atmospherically corrected and BOA reflectance images.
Hello Marios @msgouros
Yes. L2A (and L1C) are ‘operational’ (i.e. distributed) products. They are ready to use. More interesting things - such as DOP or SDB, or seagrass mapping, are for the User community to perform.
https://scihub.copernicus.eu/news/News00305
Cheers
Jan
S2 MPC Operations Manager
Thank you for clarifying this one. As I see it I must concentrate on shallow water column correction and apply afterwards a classification.
