Global change will be the defining question of the 21st Century. How does the Earth work and are we now capable of altering major global processes? The upcoming Copenhagen conference will continue that international dialog. The outcomes of these discusssions, resolutions, and international agreements depend on many political, social, economic, and ethical perspectives, but at some levels it come down to what do we believe about the Earth.
What evidence would you want to have, to believe in “strong Gaia” (see the Wikipedia article for strong vs. weak Gaia). What would that belief mean to responding to global climate change? Now think about homeostasis at the ecosystem-level. If we had strong evidence of ecosystem homeostasis relative to, for example, nitrogen deposition on forests (acid rain), what might that lead us to do about acid rain? Would we be more or less upset about the current situation?