Temporal variation of RCS from a tree trunk

Temporal variation of Radar Cross Section (RCS) from a tree trunk placed in anechoic chamber was measured with ground based scatterometor. Temporal variation of dielectric constant in a tree trunk in Tomakomai national forest was measured with Time Domain Reflectometry. Temporal variation of σHv over Tomakomai national forest was calculated from PALSAR data. The RCS from the tree trunk shows near daily variation especially for above 2GHz, while TDR and PALSAR data show the variation related with precipitation. We conclude that a few dB variations observed with PALSAR over the forest area mainly or partly come from the variation of dielectric constant for trees.