According to a report by BBC News, the group's proposals include major investment in renewable energy and the creation of thousands of new "green collar" jobs.
The new grouping said that rising greenhouse gas emissions, combined with escalating food and energy costs, mean the globe is facing one of its biggest crises since the 1930s.
Its members include former Friends of the Earth UK director Tony Juniper, Green MEP Caroline Lucas and Andrew Simms, policy director of the New Economics Foundation.
Simms warns that the combination of the current credit crunch, rising energy prices and accelerating emissions are "conspiring to create the perfect storm".
"The UK and the global economy are entering unchartered waters, and the weather forecast is not bad, but appalling," he said.
"Instead of desperate bailing-out, we need a comprehensive plan and new course to navigate each obstacle in this new phenomenon," he added.
According to the authors, within "the very real timeframe of 100 months", the world will reach the point where the risk of "runaway" climate change became unacceptably high.
The group's recommendations include massive investment in renewable energy and wider transformation in the UK, as well as the creation of thousands of new "green collar" jobs.
It also includes making low-cost capital available to fund the UK's green economic shift, and, building a new alliance between environmentalists, industry, agriculture and unions.