— A lack of mandatory standards regulating the way businesses report their greenhouse gas emissions has led to massive underestimation in the UK, according a charity-backed report.
The report, commissioned by Christian Aid, estimates that the 100 largest companies listed on the London Stock Exchange (the FTSE 100) omit about 191.42 million tonnes of carbon dioxide from the figures they report each year. According to the report, taking these "missing millions" into account would mean that worldwide activities of these companies could account for as much as 12% to 15% of global emissions - instead of the current estimate of 2.13%.
Although international standards for reporting greenhouse gas emissions exist, abiding by them remains optional unless a company is part of the European Emissions trading scheme.
Christian Aid found that only 16 of the FTSE 100 companies use internationally agreed standards. Together, these firms reported emitting 285.93 million tonnes of carbon dioxide into the atmosphere through worldwide activities over the past year. Other businesses were found to report only part of their total emissions.
"Most businesses are not obliged to reveal their emissions," a spokesperson for Christian Aid told New Scientist. "This makes it very hard to compare like with like." She said that, because one company declares its emissions rigorously, it may seem like it emits more than another company that does not.
"Our research reveals a truly staggering quantity of unreported carbon dioxide is emitted around the world by the top 100 companies on the London Stock Exchange," said Andrew Pendleton, Christian Aid's senior climate change analyst. He admitted that "we don't even know the extent of the emissions of many of the biggest companies".
Beyond Green, a UK-based sustainable development consulting firm told New Scientist that the Christian Aid report "makes a clear and compelling case that we need compulsory, standardised carbon dioxide disclosure organisations and that the wider footprint of the UK's investments and consumption worldwide need to be measured".
"Only then will we be able to quantify the UK's real contribution to global greenhouse gas emissions," Green adds.
The report was published on the same day as a "final draft" of the Intergovernmental Panel on Climate Change's report on global warming was leaked. The Guardian reports that the summary will conclude "there is a 50% chance that widespread ice sheet loss may no longer be avoided because of greenhouse gases in the atmosphere".
Researchers, however, emphasise that the report is yet to be finalised. The second chapter of the IPCC's fourth assessment report and its summary will be officially released in April 2007. The first chapter was released on 2 February.
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