Business warned to prepare for catastrophic impacts

Jo Confino in the Guardian (UK): PricewaterhouseCoopers, the world's largest professional services firm, is not known for scaremongering. So it is worth paying particular attention to its latest annual low carbon economy index. Behind the understated language, it points to a catastrophic future unless radical action is taken now to combat climate change.

"Business leaders have been asking for clarity in political ambition on climate change," says partner Leo Johnson. "Now one thing is clear: businesses, governments and communities across the world need to plan for a warming world – not just 2C, but 4C or even 6C." The trigger for its dire warning comes from the failure of the global community to reduce carbon emissions by anywhere near the amount needed to restrict temperature rises.

PwC's latest report shows the required improvement in global carbon intensity to meet a 2C warming target has risen to 5.1% every year from now to 2050. The improvement in 2011 was just 0.7% despite the global economic slowdown, and since the turn of the century the rate of decarbonisation has averaged 0.8%.

PwC, the largest of the big four accounting firms, points out that even if the 5.1% improvement might be achievable in the longer term, it is unrealistic to expect that decarbonisation could be stepped up immediately – which means that the reduction required in future years is likely to be far greater. "We have passed a critical threshold – not once since the second world war has the world achieved that rate of decarbonisation, but the task now confronting us is to achieve it for 39 consecutive years," says the report.

It adds: "Even doubling our current rate of decarbonisation would still lead to emissions consistent with 6 degrees [C] of warming by the end of the century. To give ourselves a more than 50% chance of avoiding 2 degrees [C] will require a six-fold improvement in our rate of decarbonisation....

Contemporary picture of the Burchardi flood, around 1634.