Delete---ICESat-2 leaf area index (LAI) Retrieval Comparisons

This is the first release of the LAI used for the submitted paper:

Guo et al., 2021: Exploring photon-counting laser altimeter ICESat-2 in retrieving LAI and correcting clumping effect.

The grid LAI derived from airborne LiDAR data was used to validate the LAI derived from ICESat-2, which has been validated by the field measurements and has the spatial resolution of 5*5 m.