If anyone thought that December’s historic Paris climate agreement meant the problem of climate change was officially solved, they got the wrong idea. While a critical first step, the emissions cuts pledged cannot be the end of the story if we want to stabilize our unintentional experiment with Earth’s climate.

Technically, the 195 countries in on the pact are agreeing to keep global average temperatures less than 2 degrees Celsius above pre-industrial times. In fact, a late addition to the agreement purports to aim to stay below 1.5 degrees Celsius above. Unfortunately, it now seems that the actual emissions pledges submitted by each nation (which go through 2030) don’t get us there.

A team led by Joeri Rogelj of Austria’s International Institute for Applied Systems Analysis has published a close look at those pledges to show us just where we’re at. The team compares several scenarios for future greenhouse gas emissions: a baseline “no policy” world in which no cuts are made, a world in which only existing (pre-Paris) policies are in effect, a Paris Agreement scenario, and a more aggressive scenario that would obey the 2 degrees Celsius limit.

In 2010, the world emitted greenhouse gases equivalent to about 48 billion tons of CO 2 . With no climate policy, the researchers project annual emissions would rise to about 65 billion tons in 2030. Our current policies should shave that down to around 59 billion tons, and the Paris pledges should drop it further to about 53 to 55 billion tons. (These are the numbers the researchers work with, but it’s important to note that the Paris Agreement includes five-year reviews that are intended to result in further cuts.) An optimized scenario that keeps us below 2 degrees Celsius with minimal global costs, however, would cut emissions by an additional 11 to 14 billion tons.

In order to project global temperatures through the end of this century, of course, we have to make some assumptions about what happens after 2030. In this case, the researchers basically extrapolate the trajectories of each emission scenario. After the Paris Agreement expires, emissions continue to drop at a similar rate—rather than a returning to growth or experiencing a more dramatic drop.

So here’s the damage in each scenario. In a pedal-to-the-metal no-policy world, we’re looking at more than 4 degrees Celsius above pre-industrial levels by the year 2100. Current policies (also extrapolated into the future) reduce that number to around 3.2 degrees Celsius. The Paris Agreement reduces it further to about 2.5-3.1 degrees Celsius. That’s certainly quite preferable to >4 degrees Celsius, but it’s also much higher than the 2 degrees Celsius limit that the Paris agreement was supposed to implement.

It might technically be possible to keep warming below 2 degrees Celsius with steep cuts after 2030, but it won’t be easy. Emissions would only approach leveling off by 2030, but they would have to actually go down by more than two percent each year for the next couple of decades. At the same time, efforts to capture emitted CO 2 and lock it away somewhere—something we are only doing at a few pilot projects currently—would have to ramp up big time. By 2050, we would need to be capturing 10 billion tons of CO 2 per year—the equivalent of several hundred coal plants.

Of course, doing better than the Paris pledges before 2030 would slightly extend the timetable for the remaining emissions cuts. But the fact remains that the 2 degrees Celsius goal is becoming more improbable every year.

The researchers write, “The optimism accompanying [the Paris Agreement] process has to be carefully balanced against the important challenges that current [pledges] imply for post-2030 emissions reductions. Even starting today, limiting warming to no more than 2 [degrees Celsius] relative to pre-industrial levels constitutes a societal challenge; at the same time, the warming projected from current [pledges] constitutes an important challenge on its own in terms of coping with climate impacts.”

Nature, 2016. DOI: 10.1038/nature18307 (About DOIs).