According to a study by group of scientists from five nations, the earth is rapidly approaching a “tipping point” of catastrophic and irreversible global environmental upheaval.  The research shows a combination of population growth, climate change, habitat and species extinction, and the over exploitation of energy resources threaten to cause major destructive changes to the earth similar to those not seen since the end of the last ice age, close to 14,000 years ago.  Led by Anthony Barnosky, a paleobiologist at the University of California, Berkeley, the report appears in the June 7 issue of the journal, Nature. The endeavor, the Berkeley Initiative in Global Change Biology, involved more than 100 UC Berkeley scientists from a wide range of disciplines.

The scientists used ecological modeling plus paleontological evidence centering on how much of the earth’s surface has been transformed by humans.  They calculated severe damage will occur when the percentage of usage level of the land exceeds 50 percent, anticipated when the earth’s population reaches eight billion.  The researchers also say there is an urgent need for more accurate models and observations to both anticipate future changes and predict how close the planet is to a tipping point where recovery will be impossible.

In an article in the San Francisco Chronicle, Barnosky was quoted, saying, “The science tells us that we are headed toward major changes in the biosphere.  And given all the pressures we are putting on the world, if we do nothing different, I believe we are looking at a time scale of a century or even a few decades for a tipping point to arrive.”

Barnosky’s research points to several issues:

• Global human population is growing too fast and quickly consuming available resources.
• Fossil fuels are being burned at an increasing rate causing large concentrations of carbon dioxide to enter the atmosphere.  Ocean acidity is rising at the same time.
• There are vast “dead zones” in the oceans, devoid of fish and the earth’s land mass contains far fewer types of crops and domestic animals.
• More animal species are becoming extinct, and global warming is forcing many species to seek new territory that could put them in danger of extinction as well.
• The average global temperature continues to rise.

The report’s authors, however, admit to a high degree of uncertainty as to when this catastrophic event will happen. To slow or reverse the trend, researchers say that international cooperation to slow population growth, lesson dependence on fossil fuels, increase the efficiency of food population, and develop the earth and oceans as sources of biodiversity will be required. 

At the same time, a new assessment of the environment and human wellbeing was released by the United Nations Environmental Programme (UNEP) on the eve of the Rio+20 Summit slotted for June 20-22 in Brazil.  The fifth edition of the Global Environmental Outlook (GEO-5) reported that the earth is continuing on an unsustainable path despite more than 500 internationally agreed goals and objectives.  The report found that significant progress had only been made on four of these goals: eliminating the production and use of substances that wreak havoc on the ozone layer, removal of lead from fuel, increased accessibility to improved water supplies, and more research to reduce marine environment pollution. 

In a news statement, United Nations undersecretary and UNEP executive director, Achim Steiner, said, “If current trends continue, if current patterns of production and consumption of natural resources prevail and cannot be reversed and ‘decoupled,’ then governments will preside over unprecedented levels of damage and degradation.”

The report also states that meeting sustainability goals by mid-century is possible if existing polices and strategies are changed and strengthened and offers several examples of successful policy initiatives, including green accounting, public investment, the establishment of new markets, technological innovation, green accounting and capacity building.