I am extracting four MODIS (Level 03) parameters SST, Chl-a, DOC, FLH and eleven reflectance bands time-series from google earth engine. I couldn't find the rest of ocean color variables. I am trying to calculate Kd490 and other parameters like Zeu_morel (euphotic depth), Zsd_morel (Secchi disk depth), tindx_morel (turbidity index) bbp_547_giop (particulate backscattering coefficient) from the reflectance bands. Which one of these variables are easy to calculate using band ratio? and what is the formula to do so? I found some formulas on this website but they seem like more theoretical formulas than practical!
I read this in one of the posts. "The input ratio for Kd490 is Rrs488 / Rrs547"
Is this formula correct for Kd490?
Thank you so much
Most of those products are easily computed (e.g. uses a simple equation)...Kd_490 (based on an Rrs ratio), the Zeu/sd_morel products (based on chl), and tindx_morel (based on chl and Rrs). GIOP, well that's more complex.
The Kd_490 is described here: https://oceancolor.gsfc.nasa.gov/atbd/kd_490/
The Zsd/eu_morel algorithms are described here: https://doi.org/10.1016/j.rse.2007.03.012
tindx_morel is described here: https://doi.org/10.1016/j.rse.2006.01.022
GIOP is described here:https://doi.org/10.1364/ao.52.002019
but how should it be implemented in SeaDas?
Can you reply with a screen shot of the written expression in the program?
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