Most global warming-causing gases emitted by 90 companies

Two-thirds of the greenhouse gases produced by industry are generated by just 90 companies, according to a recent study. Between 1854 and 2010 the majority of greenhouse gases that are responsible for climate change were generated by less than 100 companies, including Exxon Mobil, Chevron, Saudi Aramco and Pemex.

A new report from the Climate Accountability Institute in Colorado shows that only a few companies are responsible for large levels of emissions, such as carbon dioxide, that have helped to contribute to global warming. Researchers looked at over 200 years worth of records to attribute emissions to companies that started out by extracting fossil fuels.

A total of 914 billion tonnes of greenhouse gases are attributed to the 90 companies by the study. This is 63 per cent of the total amount of greenhouse gases - measuring at around 1,450 billion tonnes, that were emitted during the time period looked at by the researchers. Around half of the 914 billion tonnes was found to have been produced between 1986 and 2010, due to the growth in industrialisation. 

Researchers began looking at the current emissions and pollution rates, which were then applied to companies' historic production figures. The carbon value of gas, oil and coal then had to be determined in order to assess what emissions could be linked to the companies. Any fossil fuels that were used for other purposes and were not burned - therefore didn't produce emissions - were removed from the equation.

The study, published in the journal 'Climatic Change', also took into account company nationalisations or acquisitions and attributed any former company's emissions to the new owner. Emissions linked to deforestation, landfills or agriculture were not included in the figures.

The aim of the research was to prompt companies that were found to produce large amounts of greenhouse gases to make moves to reduce their carbon footprint, effectively becoming part of the solution to climate change rather than continuing to contribute towards it.