February 2016 was a stunningly warm month. According to NASA data, it was the most anomalously hot month the Earth has seen since record keeping began — fully 1.35 degrees Celsius (2.43 degrees Fahrenheit) warmer than the average from 1951-1980.

In the context of international climate policy, February is ominous as well. If you go back further in time to consider pre-industrial temperatures, then some analysts have suggested February was well over 1.5 degrees C warmer — and thus, breached a key temperature threshold cited in the recent Paris climate agreement. Up until relatively recently, 2 degrees C above pre-industrial temperatures – also cited in the Paris accord — was widely regarded as an upper limit for a “safe” level of global warming, but of late that has come into major question.

Fortunately, temperatures aren’t expected to stay this high — we are at a peak moment for the effect of El Nino on the atmosphere. The Earth should cool somewhat as more neutral conditions return. But long term warming won’t abate, and these milestones, 1.5 and 2 degrees Celsius, now feel much closer, and much more real, than ever before.

At the same time, meanwhile, two pieces of new research have questioned whether, from an energy standpoint, keeping long term warming below 2 degrees C is even likely to be possible.

Take, for instance, a study, just released as a working paper by the National Bureau of Economic Research this week. In it, Richard Newell of Duke University and two colleagues use a “harmonization” methodology to reconcile and compare future energy outlooks issued by the International Energy Agency, the U.S. Energy Information Administration, ExxonMobil, BP, and others.

Synthesizing all of these outlooks, they find an expectation of major growth in demand for energy out to 2040. And while the forecasts suggest a rapid expansion of renewable energy is also afoot, it’s simply starting from too small of a percentage of total energy to catch up very quickly. Therefore, this paper finds that “Global carbon dioxide emissions continue to rise under most projections and, unless additional climate policies are adopted, are more consistent with an expected rise in average global temperature of close to 3 C or more, than international policy goals of 2 C or less.”

“For any analyst that has been deeply immersed in energy forecasting or projections, the degree of shift that would be required in the global energy system to meet targets like 2 degrees Celsius are very different from the path that we’re currently on,” says Newell. And he says that the recent Paris climate accord, although highly significant, probably doesn’t shift the trajectory downward enough, although it does put the Earth on a path toward a faster flattening of emissions overall.

Optimists could say that this is still all based on models and projections, and that those have been wrong before. And indeed, the Duke study duly notes that past energy outlooks have missed major phenomena that upended energy markets, such as the shale gas and shale oil boom. Something like that could, assuredly, happen again — but as Newell cautions, we shouldn’t assume that it will be a simple clean energy breakthrough that undermines fossil fuels.

“We had solar costs that have come down much more quickly than people expected,” Newell says. “On the other hand, we also have had the oil and gas boom, and so, the thing that I always have to remind myself is that, when there’s technological advances in clean energy, that doesn’t mean that the incumbent sits still.”

Thus, the study ultimately suggests that the world will try really hard to get its act together in time, and quite a lot of renewables will indeed be installed — but ultimately, it may not be enough to keep to the 2 degrees C target.

A second new study, just out in Energy Policy by Glenn Jones and Kevin Warner of Texas A&M University at Galveston, raises further doubts. Using a modeling approach to take into account energy demand (expected to greatly increase), population growth (also set to boom), and greenhouse gas emissions between now and the end of the century, they find a giant energy hurdle for a world that, presumably, also wants to battle climate change.

Many more people are going to need electricity in the future as populations expand and electrification reaches many who currently lack it, note Jones and Warner. And yet at the same time, they calculate, to meet the 2 degrees C goal, half of all our energy will have to come from renewables by the year 2028. But it was only at around 9 percent in 2014, meaning that the scale-up must be massive in little more than a decade.

Considering just wind energy, the study finds, we’d need to be installing the equivalent of 485,000 5 megawatt windmills annually by 2028. That would represent “a 37-fold…expansion in the annual installation rate in only thirteen years.”

“That rate of expansion, to go from like 9 percent to 50 percent….we’ve never seen that in the history of the world’s use of energy,” says Jones. The study argues that coal, oil, and natural gas each required “35 + years to increase from 5 % to 25 % of total global energy production.” The authors therefore bluntly conclude that “it is unlikely that the < 2 C goal can be met.”

Granted, unlikely is not the same as impossible. “Not that it can’t happen, but I don’t see the world or governments or officials getting together in the timespan it would take to make a difference,” says Jones.

“Hopefully it comes as a wake-up call to people,” he says of the study.

The study does not contemplate the removal of carbon dioxide through the air through advanced “negative emissions” technologies that, all of a sudden, seem likely to be essential to meeting climate goals. But the calculations provided by the authors certainly support that conclusion.

And as if all of this is not enough, the so-called “carbon budget” of 1,000 additional gigatons of carbon dioxide, which has been used until now to determine how much humans can emit and still keep warming below 2 degrees C, may have been too generous, recent research has suggested. The budget, as of last year, could be as low as 590 – 1,240 gigatons of carbon dioxide, when current emissions are around 40 gigatons per year, a recent study in Nature Climate Change found.

A great example of how much the world is turning to renewables, and yet how it could still fall short of climate goals, comes in the form of India, one of the top countries to watch when it comes to the energy future.

As of 2014, India had 249 gigwatts of installed electricity capacity, according to the Energy Information Administration, roughly one quarter of what exists in the U.S. And this is to serve a population more than three times as large. Thus, India will greatly expand its provision of electricity to its people in the coming years. There is simply no doubt of that.

At a recent gathering of India energy experts hosted by the World Resources Institute, Ajay Mathur, the director-general of the Energy and Resources Institute (TERI) in New Delhi, and Arunabha Ghosh, CEO of India’s Council on Energy, Environment and Water, explained India’s energy outlook out to 2030. And it’s very impressive — as installed electricity capacity expands to about 800 gigawatts, they said, it is also expected to reach 40 percent renewable capacity, or 320 gigawatts.

“Going forward, our share of electricity generation from renewables will be significantly larger than China,” said Ghosh. At the same time, though, India is also expected to greatly ramp up its coal production, as well as expanding nuclear power — an all-of-the-above strategy, which will lead both to increased renewables and also increased emissions.

There may still be some other way of putting all of these pieces together. But for now, while the future will clearly hold many more renewables — and while the Paris accord will surely prove to be an important milestone — what still seems to be missing is a fast and sweeping energy transition.