Improved Modified Chlorophyll Absorption Ratio Index (MCARI)

The MCARI results from the following equation:

Index = ((VNIR - Red)-0.2*(VNIR - Green))*(VNIR / Red) using Sentinel-2 Band 5 (VNIR), Band 4 (Red) and Band 3 (Green).

The MCARI is responsive to leaf chlorophyll concentration and ground reflectance. Generally high MCARI values indicate low leaf chlorophyll content. MCARI shows weakness in predicting low chlorophyll concentrations, especially the impact of soil signal limits its functionality. In consequence, MCARI should be interpreted together with NDVI or LAI. (Nagler, Daughtry, and Goward 2000)
 

Sources

Nagler, P.L., C.S.T. Daughtry, and S.N. Goward. 2000. “Plant Litter and Soil Reflectance.” Remote Sensing of Environment 71 (2): 229. https://doi.org/10.1016/S0034-4257(99)00082-6.