The research looks at a popular 2004 approach put forward by two Princeton scientists who said the increase in carbon dioxide emissions could be stopped by dividing the task into seven “slices,” or wedges, that use existing technologies. For example, one wedge called for doubling the use of nuclear energy and another for boosting car fuel efficiency from 30 miles per gallon to 60 mpg.
Now, a team of scientists, citing the recent surge in global greenhouse gas emissions, say seven such wedges — however ambitious — aren’t enough.
“That no longer works,” says Steve Davis, an Earth-system scientist at the University of California-Irvine and co-author of the study, which appears Wednesday in the peer-reviewed journal Environmental Research Letters.
Although the level of emissions from heat-trapping greenhouse gases has fallen in the United States in recent years, it has surged worldwide as other countries rely on a primary contributor — fossil fuels — for development. The rate of increase has also accelerated.
“We have enormous respect for that earlier work,” Davis says of the wedge solution by Princeton scientists Stephen Pacala and Robert Sokolow, which aimed to stabilize emissions for 50 years and then reduce them. But, he says, the problem has worsened so much since 2004 that as many as 31 wedges would now be needed to stabilize the planet’s climate at safe levels and that emission reductions need to start sooner.
“Solving the problem requires eliminating emissions altogether,” Davis says. “That’s the only true solution.” The study says such an approach will require a “fundamental and disruptive overhaul of the global energy system” and involve new technologies. It calls for research funding to develop affordable and large-scale, carbon-free energy sources.
Co-authoring the study are Ken Caldeira of the Carnegie Institution for Science, a non-profit research group, Long Cao of Zhejiang University in China and Martin Hoffert of New York University.
This article originally appeared in USA Today 8 January 2013