Can Trump really back out of the climate deal?

With this year's United States presidential election marred by fake news, it's time for a fact-check.

During the presidential election campaign, Trump said he would "cancel" the Paris Agreement, negotiated by United Nations member countries in 2015 to limit global warming to maximum 2 degrees Celsius (3.6 degrees Fahrenheit).

Spurred on by unprecedented political will over the past year, the treaty came into force just days before the US presidential election and its unexpected result.

This included ratification by President Obama on behalf of the United States - as well as by more than 80 other nations, among them the world's other largest greenhouse gas polluters.

But can Trump really pull the US out of the Paris Agreement - and if so, how would that work?

Anti-climate platform

Trump has called global warming a "hoax" perpetrated by the Chinese to make US manufacturing uncompetitive.

Trump's election has set off alarm bells around the world - for environmentalists, among others.

The US president-elect has pledged that as soon as he is in charge as president, he would boost coal, oil and shale industries. He would support Keystone XL, the controversial oil pipeline from Canada that Barack Obama blocked on environmental grounds.

And Trump wants to prevent the Clean Power Plan, a set of regulations intended to reduce greenhouse gas emissions from power generation, which constituted Obama's climate policy linchpin, from ever coming into effect.

What's more, Trump previously called the US Environmental Protection Agency (EPA), which administers most environment and climate law in the US, "a disgrace." 

Republicans at their national convention vowed to dismantle the EPA, along with other environmental regulatory structures.

Making good on promises

And now, as president-elect, Trump has picked climate change denier Myron Ebell to head his EPA transition team.

Ebell is chair of the "Cooler Heads Coalition," a group of nonprofits that "question global warming alarmism and oppose energy-rationing policies." He has testified before Congress as a doubter of the existence of manmade climate change - global advocacy group Avaaz named Ebell one of its seven "climate criminals" at the Paris climate talks last year.

All of this is hinting at Trump planning to make true on his campaign promises.

Even so, the Paris Agreement has already become international law, and is due to take full effect by 2020. Under the framework, this means Trump could theoretically only revoke the agreement in four years' time.

How withdrawal could work

However, an anonymous source from Trump's transition team told Reuters that Trump was considering bypassing this four-year procedure for leaving the accord.

This strategy would entail either withdrawing from a 1992 convention that is the parent treaty to the Paris Agreement - which would get the US out in one year's time - or by issuing a presidential decree to delete the US signature from the Paris accord.

Faced with a Republican Congress that opposed the Paris Agreement, President Obama had to resort to executive action in order to have the US participate at all.

Although ratification of treaties generally requires a two-thirds majority from Senate, executive agreements can be instituted through executive powers vested in the president.

So although overturning a treaty generally requires congressional approval, an executive agreement can be undone by a new executive order that revokes the previous one.

Another, perhaps far simpler option if Trump intends to follow through - not counting political backlash - would be to leave the accord in place, but not take any action to comply with it.

Preemptive backlash

In any case, political backlash would be assured - and it seems already to have begun.

France's ex-president Nicolas Sarkozy proposed an EU-wide carbon tax on all US goods if Trump goes through with his promise to pull out of the Paris Agreement.

UN Secretary-General Ban Ki-moon told AFP that action on climate change has become "unstoppable." He said he hopes Trump will come around and drop his pledge to withdraw from the Paris agreement, as it would "create serious problems if anybody wants to undo it."

Germany's environment minister Barbara Hendricks echoed this, saying she is not giving up hope.

"I don't dare to predict how the US might position itself in the future, that's fortune-telling. But I am confident that treaties which are already international law will apply."

China and other countries said at the current climate change talks in Marrakesh that they will remain committed to the Paris Agreement, regardless of what the next US administration decides to do.

Pushback and cooperation

Oldag Caspar, team leader for German and EU low-carbon policy at Germanwatch, told DW that nothing has been decided yet. A chance remains that Trump won't pull the US out of the Paris Agreement after all.

And even if Trump does follow through, this could result in significant pushback.

"Since Trump's election, we've seen a lot of strong voices coming out of the US that are calling for more climate protection," Caspar said.

On Wednesday (16.11.2016), a coalition of more than 350 US companies made an appeal to the Trump administration to continue the country's climate policy, to not back out of the Paris Agreement, and to keep driving the world's decarbonization forward.

"So even if the new US government were to start a destructive climate policy, it is likely that individual US states, corporations and the people will continue their efforts to keep global temperatures well below 2 degrees," Caspar said.

Another positive development, according to Caspar, is that since the US elections, eight more countries - including Japan, Pakistan and Australia - have ratified the Paris Agreement. As of writing, more than 100 countries have officially joined the climate change deal.

 "Maybe we're going to see even more multilateralism and cooperation across countries now - and that would be a positive development," Caspar said.