According to Martin Hoffert, a physicist from the New York University, current energy technologies are not sufficient enough to reduce carbon emissions to the required level that will lower the risks associated to climate change. Scientists determined that the mean global temperature must be prevented from rising by more than 2°C above pre-industrial levels of about 280 parts per million.
Current climate models show that this will require limiting atmospheric carbon dioxide concentrations to less than 450 parts per million. The current level is approximately 385 parts per million and rising.
“So far, efforts to curb emissions through regulation and international agreement haven’t worked,” Mr. Hoffert explained in an essay in the latest issue of the journal Science. “Emissions are rising faster than ever, and programs to scale up ‘carbon neutral’ energy sources are moving slowly at best.”
He cited two reasons why present technologies cannot reduce carbon emissions to the level advocated by scientists.
First, there is the inadequate development of supporting technology for alternative energy sources. The widespread deployment of solar and wind power requires utility-scale systems that can store the intermittent supplies of power until they are needed. However, the current energy storage technologies are still either experimental or not cost-effective.
Another reason is that reliance on carbon-emitting fuels is increasing again, with new coal-fired power plants being built in countries such as China, India and even the United States.
And these new power plants could very well push carbon dioxide levels beyond prescribed limits, said Steven Davis and Ken Caldeira of the Carnegie Institution’s department of global ecology.
“The problem of climate change has tremendous inertia,” Mr. Davis explained. “Some of the inertia relates to the natural carbon cycle, but there is also inertia in the manmade infrastructure that emits carbon dioxide and other greenhouse gases.”
The pair discovered that between 2010 and 2060, existing power plants will emit an estimated 500 billion tons of carbon dioxide. They then used a climate model to gauge the impact and found that the atmospheric concentrations of carbon dioxide would stabilize at less than 430 parts per million and the increase of global mean temperatures would be less than 1.3°C.
“Because most of the threat from climate change will come from energy infrastructure we have yet to build, it is critically important that we build the right stuff now – that is, low-carbon emission energy technologies,” Mr. Caldeira concluded.
“We cannot be complacent just because we haven’t yet reached a point of no return,” he stressed.
