Atmospheric Correction
In this section, we will talk about two different processing levels, L1B Top of Atmosphere Radiance, and L2A Bottom of Atmosphere Reflectance.
L1B Top of Atmosphere (ToA) Radiance is the raw light signal that a satellite sensor measures coming from the Earth, but it still includes the effects of the atmosphere (like scattering and absorption by air and clouds). L2A Bottom of Atmosphere (BoA) Reflectance, on the other hand, is a corrected product that shows how much light is actually reflected off the Earth's surface itself, as if the atmosphere wasn't there. This makes L2A easier to use for studying surface features like vegetation, water, and soil, because it better represents what’s really on the ground.
Wyvern currently delivers all imagery as L1B Top of Atmosphere, which means that applying atmospheric corrections to the imagery is necessary before any analysis is done. This includes applying indicies like RENDVI. We are currently hard at work building an L2A BoA reflectance product, but in the meantime, there are other tools you can use to atmospherically correct our imagery.
The following table lists atmospheric correction tools that are able to easily ingest and process Wyvern data:
| Name | Type | Details |
|---|---|---|
| ATCOR | Paid | Trusted atmospheric correction tool. |
| ENVI QUAC | Paid | Built-in tool to ENVI. Extremely easy to use. |
| ACOLITE | Free | Open source atmospheric correction tool for coastal applications. |
There are also many other tools than can be used with Wyvern data, however manual work would need to be completed to ensure compatibility and correct output. These tools include Py6s, SICOR, SIAC, SL2P-CCRS, libRadtran, and many more.