Viewing page 189 of 218

This transcription has been completed. Contact us with corrections.

-4-

Many of these disruptions have been brought about by human activities. Thanks to our ability to observe the Earth from space and to the development of large-scale computer systems, we now know that economic and technological activities over the past few generations have contributed significantly to global change. Humankind is now a critical part of Earth's system. And it's clear we've still got a lot to learn about how to be a constructive part of that system.

Human activity has contributed, in large measure, to depletion of the ozone layer; to desertification of once-fertile lands; to deforestation in tropical and other forests; to acid rain and, perhaps, even to a "greenhouse effect", which some scientists believe is gradually warming the Earth's climate.

The good news, however, is that we are now in a position to understand the consequences of our actions; and, once understood, I trust, we'll be able to do something about them together. Every nation in the world will have a part to play in solving these problems, because global problems require global solutions carried out internationally. It is imperative that we join together to correlate and integrate measurements from space with ground-truth measurements all over the globe. And this can involve every nation on the face of the Earth - large and small - be it a space power or not.