Is it too late to limit greenhouse gas emissions to 2 degrees?

Published by MAC on 2012-11-11
Source: PlanetArk

Business as usual not an option, says PwC

Unprecedented world carbon emissions cuts needed by 2050: PwC

Nina Chestney

PlanetArk

6 November 2012

The world will have to cut the rate of carbon emissions by an unprecedented rate to 2050 to stop global temperatures from rising more than 2 degrees this century, a report released by PwC on Monday showed.

PwC's annual "Low Carbon Economy Index" report examined the progress of developed and emerging economies towards reducing their carbon intensity, or their emissions per unit of gross domestic product.

Global temperatures have already risen by about 0.8 degrees Celsius above pre-industrial times. Almost 200 nations agreed in 2010 at United Nations climate talks to limit the rise to below 2 degrees C (3.6 Fahrenheit) to avoid dangerous impacts from climate change.

Carbon intensity will have to be cut by over 5 percent a year to achieve that goal, the study said. That compares with an annual rate of 0.8 percent from 2000 to 2011.

"Because of this slow start, global carbon intensity now needs to be cut by an average of 5.1 percent a year from now to 2050. This rate of reduction has not been achieved in any of the past 50 years," it added.

Climate scientists have warned that the chance of limiting the rise to below 2C is getting smaller.

Global carbon emissions went up over 3 percent in 2011 to a record high, according to the International Energy Agency.

Slow Progress

Even if the 5 percent rate is achievable in the long term, decarbonisation will not be ramped up immediately, meaning that future cuts would have to be far more.

"Even doubling our current rate of decarbonisation would still lead to emissions consistent with 6C warming by the end of the century," said Leo Johnson, PwC partner for sustainability and climate change.

"To give ourselves a more than 50 percent chance of avoiding 2C will require a six-fold improvement in our rate of decarbonisation."

According to the study, European Union countries had the highest rates of decarbonisation, with Britain, France and Germany all cutting carbon intensity by over 6 percent in 2010-2011.

"The irony is that a key reason for lower energy use was the milder winter in the region. Both the UK and France also witnessed increased generation in low-emissions nuclear power, whereas Germany's exit from nuclear is reflected in its relatively lesser decline in emissions," PwC said.

The United States experienced a 3.5 percent decrease in carbon intensity in 2011, mostly due to a shift to shale gas from coal in its fuel mix and more efficient vehicles.

Decarbonisation in China and India in the last decade seems to have stalled, while Australia's carbon intensity grew by 6.7 percent last year and Japan's was up 0.8 percent.

Although major economies have promised to cut carbon dioxide emissions, the pledges combined are insufficient to meet the 2C target, PwC said.

It questioned whether some of the pledges can be met due to economic pressures.

Nations will meet in Qatar at the end of this month for the next round of U.N. climate talks when they are supposed to discuss ways of ramping up their climate targets.

(Editing by Jane Baird)

---

"Business as usual is not an option"

Key points from the PwC report:

We estimate that the world economy now needs to reduce its carbon intensity by 5.1% every year to 2050 to have a fair chance of limiting warming to 2°C above pre-industrial levels.

Even to have a reasonable prospect of getting to a 4°C scenario would imply nearly quadrupling the current rate of decarbonisation.

The decarbonisation rate required for a 2°C world has not been achieved in a single year since World War 2. The closest the world came to that rate of decarbonisation was during the severe recessions of the late 1970s/early 1980s (4.9% in 1981) and the late 1990s (4.2% in 1999).

The expected reduction in emissions resulting from the current economic slowdown has not materialised, partly because of sustained growth in emerging markets.

The observed relationship between economic growth and CO2 emissions is also asymmetric - emissions tend to grow proportionally with economic growth, but fall by less than the rate of economic decline.

The only way to avoid the pessimistic scenarios will be radical transformations in the ways the global economy currently functions: rapid uptake of renewable energy, sharp falls in fossil fuel use or massive deployment of CCS, removal of industrial emissions and halting deforestation.

This suggests a need for much more ambition and urgency on climate policy, at both the national and international level.

Either way, business-as-usual is not an option.

Regardless of the outcomes at the UN climate change summit in Doha this year, one thing is clear. Governments and businesses can no longer assume that a 2°C warming world is the default scenario.

Any investment in long-term assets or infrastructure, particularly in coastal or low- lying regions, needs to address more pessimistic scenarios.

Sectors dependent on food, water, energy or ecosystem services need to scrutinise the resilience and viability of their supply chains.

More carbon intensive sectors need to anticipate more invasive regulation and the possibility of stranded assets. And governments' support for vulnerable communities needs to consider more drastic actions.