[SM:Indices] CARI

According to the spectral reflectance of plant leaves (between 550 nm and 700 nm) it can be considered constant even if the chlorophyll content of leaves is variable. Based on this relationship, Kim et al. (1994) measured the level of absorption at 670 nm and linked the reflection peak at 700 nm and 550 nm; the Chlorophyll Absorption Ratio Index (CARI) was then developed and can be expressed as:

This is the formula in the original paper by Kim et al. (1994) which was adopted by Cogato et al. (2020), specific only for Sentinel satellite as:

CARI= (REDEDGE5)/RED *√((a.RED+RED+b)^2)/((a^2+1)^0.5 )

a= (REDEDGE5 - GREEN)/150; a which is drawn from the 700nm to 550nm band forms the baseline to measure the depth of the chlorophyll absorption.

b= GREEN-((REDEDGE5-GREEN)/150,550); b is defined as CAR. CAR is the shortest distance from the 670nm band to 550nm- 700nm line.

The semantic model represents the dependenies for the formula by Cogato et al. (2020). The discrete wavlengths of REDEDGE5, GREEN, and RED of Sentinel 2 platform are 0.705 μm, 0.56 μm, and 0.665 μm respectively. The tasks related to CARI are also decribed in the model which are connected to theme/ subdomain as displayed here.