Two years to the day after 195 nations adopted the Paris Agreement, French President Emmanuel Macron will convene a follow-up climate summit Tuesday to jump-start the lagging transition to a greener global economy.
Launched in part to counter US President Donald Trump's decision to exit the landmark 2015 treaty, the One Planet Summit -- co-sponsored by the United Nations and the World Bank -- will centre on how to finance the shift in developing countries trying to simultaneously reduce their carbon footprints, adapt to climate change impacts, and accommodate growing populations.
"The focus on finance is particularly timely because that was the area we had the least progress on at the COP23," said Alden Meyer, a climate policy expert at the Washington-based Union of Concerned Scientists, referring to the "Conference of the Parties" UN negotiations in Bonn last month.
Some 50 world leaders are set to attend the Paris meeting, including Mexico's Enrique Pena Nieto, Theresa May of Britain, Spain's Mariano Rajoy, European Commission President Jean-Claude Juncker, and numerous African leaders.
UN Secretary-General Antonio Guterres will also be in attendance, along with ministers from China, India, Canada.
Officially, the United States -- which helped seal the Paris deal under Barack Obama -- will be represented by a low-level official from the Paris embassy. In November, an aide to Macron said Trump had not been invited.
But what some call "the other America" will also be present in force: California Governor Jerry Brown, whose state -- the sixth largest economy globally -- boasts among the most ambitious carbon-cutting targets in the world; former New York Mayor Michael Bloomberg, who has spearheaded a climate coalition of dozens of megacities, and corporate guidelines for assessing climate risk; and megastars Arnold Schwarzenegger and Leonardo Di Caprio.
"It's a mobilisation of all those who want to pick up the pace," said Laurence Tubiana, CEO of the European Climate Foundation and one of the main architects -- as France's climate ambassador -- of the Paris pact.
"Everything must be done to show that it is necessary and possible to do more than what was pledged in 2015," she told AFP.
The Paris Agreement calls for capping global warming at "well under" two degrees Celsius (3.6 degrees Fahrenheit), and at least $100 billion per year (85 billion euro), from 2020, in climate finance to poor nations. So far, neither commitment is assured.
Voluntary national plans, annexed to the treaty, to cut greenhouse gas emissions would still result in a rise of 3 C by century's end, a recipe for human misery on an unprecedented scale, scientists say.
With only a single degree Celsius of global warming so far, the planet has already seen a crescendo of deadly droughts, heatwaves and superstorms engorged by rising seas.
Ramping up financial flows to the developing world is also not on track, especially when long-term needs -- beyond the 2020 horizon -- are taken into account.
"One of the big topics in Paris next week is the need to scale up financing, which is still not nearly enough to meet the Paris commitments," said World Bank President Jim Yong Kim.
More broadly, the International Energy Agency has estimated it will take $3.5 trillion (3 trillion euros) a year in investments until mid-century to contain the rise of global temperatures and retool the global economy.
Macron's team foresees a dozen "major announcements" during the summit.
A new "Transport Decarbonisation Alliance" may, for the first time, constrain the rapidly expanding shipping sector, which -- if it were a country -- would be the 7th or 8th largest CO2 emitter.
The transport sector accounts for 15 percent of man-made CO2 emissions, on track to increase 50 percent by mid-century.
The Powering Past Coal Coalition of nations committing to shutter coal-fired power plants, launched last month, will likely take on new members, and a couple dozen countries that have laid out climate strategies to 2050 will also be joined by a raft of cities and sub-national regions.
"This is the real world, with leaders and ministers and business leaders and NGOs coming to talk about what's happening in the real economy," said Meyer.
The number of global companies committed to implementing Bloomberg’s climate-risk assessments will also grow, sources said.
A large group of institutional investors, meanwhile, will band together in a five-year campaign to pressure companies with large carbon footprints.