4 things to know about the Paris climate agreement

Today, President Donald Trump announced his decision to withdraw the United States from the Paris climate agreement. The deal, joined by all but two countries (Syria and Nicaragua), is a broad framework designed to nudge nations to prevent catastrophic climate change.

Update: President Trump pulls US out of Paris climate agreement

The deal was hammered out over weeks of tense negotiations in December 2015 and weighs in at 31 pages. And what it does is actually pretty simple. Here’s a refresher.

The backbone of the Paris agreement is the global target of keeping global average temperatures from rising 2°C (compared to temperatures pre-industrial revolution) by the end of the century. Beyond 2 degrees, we risk dramatically higher seas, changes in weather patterns, food and water crises, and an overall more hostile world.

Critics have argued that the 2-degree mark is arbitrary, or even too low, to make a difference. But it’s a starting point, a goal that, before Paris, the world was on a track to wildly miss.

To accomplish this 2-degree goal, the accord states that countries should strive to reach peak emissions “as soon as possible.” (Currently, we’re on track to hit peak emissions around 2030 or later, which will likely be too late.)

But the agreement doesn’t detail exactly how these countries should do so. Instead it provides a framework for getting momentum going on greenhouse gas reduction, with some oversight and accountability. For the US, the pledge involves 26 to 28 percent reductions by 2025. (Under Trump’s current policies, that goal is impossible.)

195 countries have agreed to it. But there’s also no defined punishment for breaking it. The idea is to create a culture of accountability (and maybe some peer pressure) to get countries to step up their climate game.

In 2020, delegates are supposed to reconvene and provide updates about their emission pledges, and report on how they’re becoming more aggressive on accomplishing the 2-degree goal.

There’s a fundamental inequality when it comes to global emissions. Rich countries have plundered and burned huge amounts of fossil fuels, and gotten rich from them. Poor countries seeking to grow their economies are now shunned from using the same fuels. Many low-lying poor countries also will be among the first to bear the worst impacts of climate change.

So as part of the Paris agreement, richer countries, like the US, are supposed to send $100 billion a year in aid by 2020 to the poorer countries. And that amount is set to increase over time. Again, like the other provisions of the agreement, this isn’t an absolute mandate.

The Paris agreement is largely symbolic, and it will live on even if Trump withdraws the US. But as Vox’s Jim Tankersley writes, “the accord will be weakened, and, much more importantly, so will the fragile international coalition” around climate change.