LAI is a dimensionless index measuring the one-sided green leaf area over a unit of land (m^2 / m^2).
Note that the LAI script is as implemented in SNAP but without input and output validation! Input/output values which are suspect are not reported or changed. Most values, however, do not fall under this category. Visualized as an interval from 0-3. This can be adjusted in the evaluatePixel method.
Leaf area index, Rome. Acquired on 08.10.2017.