Twenty years after the World Commission on Environment and Development (the Brundtland Commission) brought out its highly influential report, Our Common Future, a new study warns that humanity is at grave risk unless it finds ways to combat climate change and species extinction and feed a growing global population.

In October 2007, the United Nations Environment Programme (UNEP) announced the publication of Global Environment Outlook: Environment for development (GEO-4), the latest in UNEP’s series of flagship reports. Prepared by approximately 390 experts and reviewed by more than 1,000 others residing worldwide, GEO-4 “assesses the current state of the global, atmosphere, land, water and biodiversity, describes changes since 1987, and identifies priorities for action,” according to UNEP’s October press release.

GEO-4 echoes the Brundtland Commission in claiming that the ‘environmental crisis,’ ‘development crisis’ and ‘energy crisis’ are actually one single crisis, and that growing human numbers alone are leading to: declining fish stocks; loss of fertile land through degradation; unsustainable pressure on resources; dwindling amounts of available fresh water; and, risk that environmental damage could pass the point of no return.

In terms of climate change, GEO-4 says the threat is so great that “large cuts” urgently need to be made in greenhouse gases by mid-century. The report also warns that “we are living far beyond our means” and that “humanity’s footprint is 21.9 hectares per person while the Earth’s biological capacity is, on average, only 15.7 hectares per person.”

Despite the fact that political will and leadership is needed to make climate change a global priority, the report brands today’s global response as “woefully inadequate” and finds “a remarkable lack of urgency” in tackling the problem.

While the report avows that technology can reduce human vulnerability to environmental stresses, it also identifies a need “to correct the technology-centred development paradigm.”

“I sincerely hope GEO-4 is the final [wake-up call],” says UN under-secretary general and UNEP executive director Achim Steiner. “The systematic destruction of the Earth’s natural and nature-based resources has reached a point where the economic viability of economies is being challenged—and where the bill we hand on to our children may prove impossible to pay.” The entire contents of GEO-4 can be found at .