A global accord to tame global warming pending approval at UN talks in Paris on Saturday would be a huge blow to the fossil-fuel industry, Greenpeace and other prominent environment groups said.
"The wheel of climate action turns slowly, but in Paris it has turned. This deal puts the fossil fuel industry on the wrong side of history," Greenpeace International executive director Kumi Naidoo said.
Greenpeace, major green groups and climate change researchers gave a mixed report card on the many details in the planned accord, which still needs to be endorsed by ministers from 195 nations at the talks.
But they emphasised that by striving to limit warming to 1.5 degrees C (2.7 degrees Fahrenheit) over pre-Industrial Revolution temperatures, the draft accord would have an impact.
"That single number, and the new goal of net zero emissions by the second half of this century, will cause consternation in the boardrooms of coal companies and the palaces of oil-exporting states," Naidoo predicted.
Researchers and activists declared that the agreement, if it is adopted by ministers, would make history.
"The Paris Agreement marks a new form of international cooperation –- one where developed and developing countries are united by a common and fair framework," said Jennifer Morgan, global director of the climate programme at the World Resources Institute (WRI), a Washington-based think tank.
"The agreement is both ambitious and powered by the voices of the most vulnerable."
May Boeve, executive director of 350.org, an organisation pressing financial institutions to divest from fossil fuels, also said the 1.5C reference was key.
"This marks the end of the era of fossil fuels. There is no way to meet the targets laid out in this agreement without keeping coal, oil and gas in the ground," Boeve said.
"The text should send a clear signal to fossil fuel investors: divest now."
Emma Ruby-Sachs, acting executive director of Avaaz, another prominent campaigning group that helped organise giant rallies around the world before the talks started last month, expressed similar sentiments.
"If agreed, this deal will represent a turning point in history, paving the way for the shift to 100-percent clean energy that the world wants and the planet needs," Ruby-Sachs said.
"By marching in the streets, calling leaders and signing petitions, people everywhere created this moment, and now people everywhere will deliver on it to secure the future of humanity."
But Tim Gore, policy director at British charity Oxfam, said the provision in the text aiming to cap global warming at 1.5C would require an unprecedented global effort.
The emissions reduction plans submitted by some 185 nations ahead of the talks have put Earth on a path to least about 3.0C degrees of warming.
"The 1.5C degree target is an important moral victory, but—as we have heard—it may yet ring hollow unless we see significant increases in action in the years ahead," Gore said.
Morgan echoed his warning, noting nations around the global must accelerate the pace of change.
"World leaders need to build on the momentum created by the Paris moment and move even faster and further toward a decarbonised economy."
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