On Earth, there is much change afoot.  The changes are many and rapid, perhaps more rapid than at any time in human history; perhaps more rapid than at any time in Earth’s history.  The accumulation and interaction of these changes may well threaten our well-being and our planet’s well-being.

There are shortages of clean and accessible freshwater, degradation of terrestrial and aquatic ecosystems, increases in soil erosion, loss of biodiversity, changes in the chemistry of the atmosphere, alterations of the coastal zone, declines in fisheries, and the possibility of significant changes in climate. These changes are over and above the stresses imposed by the natural variability of a dynamic planet.

The linked challenges of confronting and coping with global environmental change and addressing and securing a sustainable future are daunting and immediate, but they are not insurmountable. The challenges can be met, but only with a more vigorous and visionary approach to understanding our changing planet. It requires a new stage in the Exploration of the Earth from space.