title: Sensing a changing world.
authors.affiliation: Centre for Geo-Information, Wageningen University, Droevendaalsesteeg 3, 6708 PB Wageningen, The Netherlands; E-Mail:  lammert.kooistra@wur.nl.
authors.forename: Arend
authors.initials: A
authors.lastname: Ligtenberg
authors.forename: Lammert
authors.initials: L
authors.lastname: Kooistra