We describe the rationale for long-term monitoring of global climate f
orcings and radiative feedbacks as a contribution to interpretation of
long-term global temperature change. Our discussion is based on a mor
e detailed study and workshop report (Hansen et al., 1993b). We focus
on the potential contribution of a proposed series of inexpensive smal
l satellites, but we discuss also the need for complementary climate p
rocess studies and ground-based measurements. Some of these measuremen
ts could be made inexpensively by students, providing both valuable cl
imate data and science educational experience.