Unprecedented Carbon Reductions Needed to Prevent Catastrophe, Reports PwC

At least six degrees Celsius of global warming could be possible by century's end if current rates of growth in fossil fuel emissions remain stable, according to a new analysis from PwC, one of the "Big Four" accounting firms.

Most climate experts agree that a rise in average global temperatures of over two degrees Celsius would be extremely serious, resulting in rising sea levels, receding coast lines, floods, more extreme weather, and crop loss. The effects of a six degree Celsius rise would be completely catastrophic.

The PwC report shows that while global carbon emissions intensity (a metric that measures emissions per unit of GDP) was reduced 0.7% in 2011, limiting global warming to just two degrees Celsius would mean reducing global carbon intensity by an average of 5.1% per year. Since 1950, when PwC's carbon emissions intensity records began, such reductions have never been achieved.

Emissions growth in emerging economies has been especially pronounced, with total emissions growing by 7.4% in 2011. In the developed world, France, Germany, and the UK, all countries with relatively robust climate change policies, achieved record levels of annual carbon emissions intensity reductions.

The UK has pledged to reduce emissions by 34% compared with 1990 levels. The PwC report shows that such reductions would require action on a scale equivalent to shutting down all the UK's coal-fired power plants.

"The new reality is a much more challenging future in terms of planning, financing and predictability," said Jonathan Grant, Director of Sustainability and Climate Change at PwC. "Even doubling our current annual rates of decarbonisation globally every year to 2050 would still lead to six degrees Celsius, making governments' ambitions to limit warming to two degrees Celsius appear highly unrealistic."

PwC released the report to coincide with the run up to the upcoming UN Climate Summit in Doha. "The analysis illustrates the scale of the challenge facing negotiations," said PwC of the upcoming summit.

Previous international climate conferences, such as the Copenhagen Climate Council in 2009, have thus far failed to yield satisfactory commitments from business and governments to curb climate change.

Still, the situation is far from hopeless. Among the more promising solutions is the proposal to adjust the price of carbon to reflect the negative effects of carbon emissions.

"Almost nothing happens without a market signal," says Mark Reynolds, Executive Director of Citizens Climate Lobby, a group working to pass climate change legislation in the United States.

Increasing the price of carbon by removing current subsidies and taxing emissions will incentivize the development of renewable energy and foster innovation, says Reynolds.

Moreover, most of the technology required to shift from fossil fuel to clean, renewable energy already exists, according to research conducted by Stanford's Mark Jacobson and the University of California's Mark Delucchi.

Using data from the U.S. Energy Information Administration, Jacobson and Delucchi have shown that a massive global shift from fossil fuels to renewable energy, requiring a total commitment from government, business, and civil society, could curb carbon emissions enough to prevent the worst possible outcomes of climate change.

"We're heading into uncharted territory for the scale of transformation and technical innovations required," said Leo Johnson, a partner at PwC. "Whatever the scenario, or the response, business as usual is not an option"

Image credit: Dominic Alves