400 little reminders

As global carbon dioxide levels edge closer to the dangerously high level of 400 parts per million (ppm), Paul Suff reflects on the world's slow progress to cut emissions

At the end of April, the daily CO₂ level measured by the Mauna Loa Observatory in Hawaii was 399.72ppm. At the advent of the industrial revolution in the 18th century, the level was around 280ppm. And, when Charles Keeling, founder of the Hawaiian monitoring station, started measuring atmospheric greenhouse gas in 1958, the level was 316ppm.

To put the 400ppm figure further into perspective: the last time it was recorded was around 2.5–5 million years ago, during the Pliocene epoch, a period when average temperatures around the world were 3–4°C higher than now (10°C at the poles) and sea levels were up to 40 metres higher than current levels.

That doesn’t necessarily mean we’re on course for a similar scenario. For one thing, the speed at which CO₂ levels have risen over the past century is unprecedented, so we are entering the unknown. But it does suggest that our ability to restrict the rise in global temperature to 2°C above pre-industrial times – a level scientists say would avoid dangerous climate change and one most governments endorsed at the Cancún climate conference in 2010 – is looking increasingly remote.

The Bonn round of climate negotiations has just closed without any breakthrough towards a new international agreement due in 2015. Christiana Figueres, executive secretary of the United Nations Framework Convention on Climate Change, said no nation was doing enough to combat global warming.

Figueres reminded governments during the meeting that, while they are on track to meet the milestones they have set themselves, they are not yet on track to meet the demands of science. Indeed, we carry on burning fossil fuels as though there are no repercussions for the planet.

There is a continuing belief among many that recoverable fossil fuels should go up in smoke. A report from Carbon Tracker and the Grantham Institute on Climate Change and the Environment at the LSE illustrates the short-sightedness of such an approach and its incompatibility with global climate change goals.

Nonetheless, governments persist in heavily subsidising the oil and gas industries, encouraging producers to scour the ends of the Earth to locate new sources. The IMF recently revealed that $480 billion is spent annually on direct fossil fuel subsidies, mostly in developing countries, while an additional $1.4 trillion is spent on indirect subsidies.

As the IMF points out, energy subsidies distort resource allocation by encouraging excessive energy consumption, artificially promoting capital-intensive industries, reducing incentives for investment in renewable energy, and accelerating the depletion of natural resources.

The Washington-based body also notes that subsidies mostly benefit higher-income households, increasing inequality. The rejection of plans to underpin the plummeting price of allowances in the EU emissions trading scheme is another illustration of a reluctance among policymakers to make the kind of shift needed to wean us off our addiction to fossil fuels.

Passing the 400ppm threshold is an important reminder that our chances of achieving the 2°C target are fast melting away. It’s also worth recalling that the World Bank said last year that the current trajectory of emissions indicated a level of warming by the end of century that is more like 4°C than 2°C. Such a rise in temperature would trigger cataclysmic changes, including extreme heatwaves and a sea-level rise – back to the Pliocene epoch, then.