Members of Greenpeace at the Brandenburg Gate in Berlin. Credit:Reuters The encounter was a prelude to what promises to be a bitter battle in Paris next year, where countries are intended to sign a new binding treaty on radical action against global warming. Countries including – but not limited to – the United States, Brazil, China and Saudi Arabia fought to ensure the summary could not be used as a weapon against them in pre-Paris negotiations. The IPCC Working Group III report found that, in order to keep temperature change below two degrees, the world will have to quickly switch over to an energy supply dominated by renewables such as wind and solar power, with carbon-capture technology mopping up the remaining fossil fuel use. However several authors said that teams of negotiators sent in by governments had refused to accept controversial parts of the report for inclusion in the summary of policymakers. Their work only survives in the full, technical report, which will be read by far fewer people, and was not released to the media on Sunday. Some of the economists and scientists involved even considered withdrawing their work entirely, so they could speak without having to toe the eventual IPCC line.

The report's co-chair Dr Rajendra Pachauri. Credit:Reuters Fairfax was told that the co-chair of Working Group III, Professor Ottmar Edenhofer, is one of those aggrieved by changes. It is believed he may use "unadulterated" parts of the report, as well as the amended summary, in a presentation at Technical University in Berlin on Monday. However he said that getting governments involved created “ownership” of the report’s conclusions, and “there’s nothing wrong with that as long as scientists have control over the full report”. Economist Reyer Gerlagh, of Tilburg University in the Netherlands, was a co-ordinating lead author on a chapter of the report. He saw a lot of his work – exploring the link between economies and their carbon emissions - deleted from the summary over the last week. “Some governments [said] we cannot write things that they forsee will immediately have consequences in international negotiations,” Professor Gerlagh said. “They cannot change the scientific findings. But they can say there are things that are not [appropriate] to be told at [the SPM] level.

“It left me depressed personally, initially ... I am not paid for this work. I do most of this work on the weekend, in evenings and on holidays. My payment is not in money or time, my payment is that I believe I can contribute to society’s benefit by providing the information. Despite this, Professor Gerlagh said he was not angry: “I can understand their point,” he said of the countries who asked for changes or deletions. In other parts of the summary, objections from rich nations resulted in the removal of a line saying: “In 2010, ten countries accounted for about 70 per cent of CO2 emissions from fossil fuel combustion and industrial processes.” They also demanded, and won, removal of a line reporting that ethical mitigation of climate change would require the developed world to transfer “hundreds of billions of dollars per year” to non-OECD countries to invest in green technologies. Objections from "upper middle income" countries resulted in the deletion of a graph that showed the stunning rise in emissions from those countries in the decade to 2010, compared with other parts of the world.

“The atmosphere has of course been contentious on some details,” said Stephan Singer, director of energy policy for the WWF, who was an observer during the week’s debate. “Some of the stuff is much more clearly spelled out in the underlying chapters than it is in the [summary].” But Dr Singer said the alterations should not be allowed to distract from the central message. Loading “This document is sufficient enough to tell governments what to do to stay below two degrees [temperature rise], despite some vague and ambiguous language [added by] the governments which was based on consensus and haggling back and forth for very long hours.” Report co-chair Dr Rajendra Pachauri, asked what had been omitted from the summary, said “the entire IPCC process and the approval of the [summary] is based on debate and discussion and naturally when you have different points of view there will be disagreement. The strength of the process is that we were able to resolve them.”