In less than two weeks, thousands of people on six different continents will take to the streets to call on world leaders to prevent the catastrophic warming of our planet:
"Politicians all over the world cite a lack of public support as a reason not to take bold action against climate change. So on 21 September we will meet this moment with unprecedented public mobilisations in cities around the world," wrote a coalition of NGO's in the Guardian earlier this week.
Billed as the largest climate march in history, the mass protest will come two days before heads of state gather in New York for an emergency United Nation's summit to discuss the state of our climate.
Organized by the head of the UN Ban Ki Moon, the September 23 gathering is designed to spur ambitious action ahead of next year's all important climate talks in Paris. Next December, world leaders are expected to strike a new deal to rein in carbon emissions responsible for the warming of our planet.
And, striking a solid binding treaty couldn't be more pressing.
According to a recent report from the World Meteorological Organization, "we are running out of time."
As CO2 remains trapped in the atmosphere for centuries, its "cumulative impact" means that even if all emissions stopped tomorrow, our planet is still locked in for a certain degree of warming: "The laws of physics are non-negotiable," warned Michel Jarraud, the head of the WMO
And, to make matters worse, the amount of CO2 absorbed by the world's oceans and forests appears to be "faltering":
"So far these 'carbon sinks' have been locking away almost half of all the carbon dioxide we emit. If they begin to fail in the face of further warming, then our chances of avoiding dangerous climate change become very slim indeed," said Professor Dave Reay from the University of Edinburgh.
That grim warning came a few weeks after a draft of the UN's latest climate report revealed that the risk of "severe, pervasive and irreversible impacts" from global warming are increasing, overwhelming current political efforts to contain the crisis.
Last September, the Nobel Peace prize winning body warned that our planet is warming much faster than expected. Temperatures may now breach the two degrees Celsius mark within the next thirty years.
And, although 2C is widely cited as the upper safe limit of warming, according to Nasa's former climate scientist James Hansen, it is "a prescription for long term disaster."
Echoing those views, one of Nato's most senior officials Jamie Shea says that such a temperature rise has the potential to ignite what he describes as the "development terrorism nexus:"
It will encourage terrorist groups to grow, whilst hampering military efforts to deliver humanitarian aid to areas effected by drought, flooding or storms:
"If we do nothing and there is no agreement, we could go up to more alarming scenarios. So purely in terms of managing the challenges we have at the moment, we can't afford to make this problem worse than it is already."
Five years ago, world leaders vowed to limit the warming of our planet to two degrees celsius. But, according to a recent PwC report, "we are way behind" even meeting that target:
"What we're saying in this report is there is an increasing gap between the talk of two degrees and the reality of what we are on track for," says Jonathan Grant from PwC.
The report echoes similar warnings made by a roadmap presented to the UN in July. According to that report, the 2C target is still possible, but global carbon emissions "will have to approach zero by the second half of this century."
It says that current emission targets are simply way too conservative: "By and large, national targets are not derived from an assessment of what needs to be done to meet the 2C target."
It recommends nothing short of a radical energy transformation amongst the world's largest economies. And, while that power revolution may seem challenging, it is far from impossible. Last year, nearly a quarter of the world's electricity came from green energy sources.
And, according to a recent report from Citigroup, the "age of renewables" has already dawned in the US. It says that both solar and wind have become cost competitive with natural gas, and will continue to "gain market share from coal and nuclear" in the future.
Moreover, if global fossil fuel subsidies were slashed, and plowed into the clean power sector instead, we will have funded the start of our next energy revolution, says the head of the World Bank Jim Yong Kim.
a coalition of NGO's in the Guardian wrote this week:
"There is only one ingredient that is required: to change everything, we need everyone. History is our proof that the impossible is smaller than we think. The abolition of slavery. The end of apartheid. The spread of universal suffrage. All proof that the future is ours to shape. We just need to step out and claim it."
As Thomas Jefferson once said: "Each generation needs a revolution." With a steep temperature rise sitting on our collective horizon, reining in climate change must be ours, for as Paul Gilding, author of The Great Disruption points out: "We'll be growing up in war. Not a war between civilizations, but a war for civilization. It will take every mother, every father and every child. But, this could be our finest hour."
After all, "nothing is more powerful than an idea whose time has come."