The first cell had to develop during a well-defined window of opportunity. Whatever the chemical processes were that led to the first organism capable of reproducing itself, we know that those processes had to take place rapidly. We know that Earth, like all the other planets, went through a period of great bombardment.
During this period, large chunks of debris fell onto the planets from space, bringing a large enormous amount of energy with them. An impact involving an asteroid several hundred miles across. Impacts that have shaped the world we live in today.
Earth stewardship involves shaping trajectories of social-ecological changes at local-to-global scales to enhance ecosystem resilience and human well-being. Over the next decade or two, society has a window of opportunity to radically redefine our relationship with the planet to reduce risks of dangerous global changes that could otherwise seriously degrade Earth’s life-support systems.
Building on the U.N. Millennium Development Goals (MDG), which provide a vision for a sustainable and equitable future, and ESA’s Sustainable Biosphere Initiative, which defines a research agenda for a sustainable biosphere, earth stewardship uses sustainability science to shape pathways toward MDG goals during a time of rapid social-ecological change. Examples include (1) understanding the causes of polar ozone holes and reducing the production of ozone-destroying chemicals that caused them (global scale); (2) transformation of management of the Great Barrier Reef in Australia to protect marine biodiversity and livelihoods (regional scale); and (3) assessment, mitigation, and adaptation of New York City to minimize impacts of climate change (local scale).
Earth stewardship requires a new ethic of environmental citizenship on the part of individuals, businesses, and governments. This must be based on a clear understanding of the consequences, tradeoffs, and opportunities associated with action choices that influence the trajectory of our planet. This in turn requires effective communication of issues and opportunities and improved alignment of incentives with those social norms that foster sustainable human behavior.
We already know enough about the causes of recent global change to begin formulating paths towards more sustainable trajectories at local-to-global scales. Such strategies should enhance ecosystem resilience and human well-being but maintain flexibility to learn and adapt to the inevitable surprises.