The “earth” part of the title of this special issue from Scientific American is no doubt self-explanatory, but why “3.0”? Because this planet is no longer simply the home of our species: it is also our creation. And as with any product, sometimes it is prudent to upgrade its quality.

If you will indulge the analogy further, Earth 1.0 was the world that persisted and evolved for billions of years, up until very recently. The environment was dominated by closed ecological loops and a few geological and astronomical processes, such as the movements of continents and the brightness of the sun. As such, life was highly sustainable. Even after we humans developed agriculture, which considerably enlarged our footprint on the environment, our overall influence was fairly small and localized.

That changed two centuries ago with the arrival of Earth 2.0, when the industrial revolution gave the human race the leverage to achieve unprecedented health and prosperity but at the price of wanton consumption of natural resources. Today we have unwittingly become the major drivers of potentially disastrous climate change. We have extinguished species at a rate not seen since the end of the dinosaurs. We have depleted ocean fisheries so severely they could collapse by midcentury. And yet much of the human population still suffers awful poverty and lack of opportunity.

Earth 3.0 is thus the new way forward that we need to establish, one with all the prosperity of 2.0 but also the sustainability of 1.0. And it is in that spirit that we present this issue, which explores and celebrates opportunities for both economic and environmental progress.

Building a better future for ourselves and the rest of the planet is possible, but it will involve action—sometimes drastic action—at every level of society, from elected officials and CEOs to individual consumers. Decisions will need to be informed by knowledge of the relevant underlying science and the available technologies. The right solutions will address both environmental problems and concerns about economic development rather than sacrificing one for the sake of the other.

We are proud to offer Scientific American Earth3.0 as a tool for promo­ting the awareness and discussions that can encourage progress.

Inside this issue:
Global Warming: Beyond the Tipping Point
The world's most outspoken climatologist argues that today's carbon dioxide levels are already dangerously too high. What can we do if he is right?

Growing Vertical: Skyscraper Farming
Cultivating crops in downtown skyscrapers might save bushels of energy and provide city dwellers with distinctively fresh food

Eco-Cities: Urban Planning for the Future
Massive developments proposed for the U.S., China and Abu Dhabi aim to reduce or even eliminate the environmental cost of city living

Is Focusing on "Hot Spots" the Key to Preserving Biodiversity?
Preserving biodiversity in rich habitats is good. But global warming and other new threats may call for a new strategy

Energy versus Water: Solving Both Crises Together
Water is needed to generate energy. Energy is needed to deliver water. Both resources are limiting the other—and both may be running short. Is there a way out?

For National Security, Get Off Oil
Former CIA director R. James Woolsey says America's oil dependence is a grave threat

LEED Compliance Not Required for Designing Green Buildings
Constructing buildings to the LEED standard can conserve energy and materials—or be exploited for promotional gain