In 2015, when the countries of the world hammered out the Paris Agreement, they committed to limiting global temperatures to 2 degrees Celsius above preindustrial levels and “pursuing efforts” toward keeping them below 1.5 degrees C. The plan didn’t work out so well. Ten years later, the planet might have crossed that lower threshold sooner than expected.
A pair of new studies in the journal Nature Climate Change looked at historical data and came to the conclusion that the record heat last year — the first year to surpass 1.5 degrees C — wasn’t a temporary fluke, but a sign that the world is now soaring past this influential climate target over the long term. The new year continued that upward trajectory. Even as a natural cooling pattern called La Niña took hold recently, January managed to be hotter than ever, clocking in at a record 1.75 degrees C warmer than the preindustrial average.
One analysis of the two studies warned that Earth had entered a “frightening new phase.” It’s a reflection of the language that has been used around 1.5 C ever since the Intergovernmental Panel on Climate Change, the United Nations-backed team of leading climate experts, wrote an influential report in 2018 on the consequences of exceeding that threshold, which it estimated would happen in 2030. Headlines warned that the world had 12 years to avert climate catastrophe. The line was echoed by the young Swedish activist Greta Thunberg and Representative Alexandria Ocasio-Cortez from New York. So is the world now at the edge of disaster?
Mike Hulme, a professor of human geography at the University of Cambridge, asserts that it isn’t. “There’s no ‘cliff edge’ that emerges from any of the scientific analyses that have been done about these thresholds,” he said. “They are, in many senses, just arbitrary numbers plucked because they are either integers or half of an integer.”
Hulme, who has been studying the way people think about climate change for decades, argues that an obsession with global temperatures misunderstands why people care about climate change in the first place: They care about how it affects their lives, not abstract readings of the thermometer. He’s also argued that climate advocates should stop chasing a series of “deadlines” to try to drum up enthusiasm for meeting these goals.
Grist spoke with Hulme to learn more about how setting these deadlines can backfire and if there’s a better way to talk about how to make progress on climate change. This interview has been condensed and edited for clarity.
Q. You’ve written that the 1.5 C goal “painted the world into a dangerous corner.” What exactly was dangerous about it?
A. The danger of this goal is that it was always impossible to achieve — or 99 percent impossible to achieve — 10 years ago. And everybody, I think, who understands both the dynamics of the physical climate system, and also the dynamics of the world energy system, understood that — 1.5 became a campaigning number around which civic groups, activists, and youth entrepreneurs mobilized: “1.5 to stay alive.” It was interpreted as being if 1.5 was breached, then the world either moved into an entirely different physical state that was dangerous compared to 1.4 — or, and this came along later, that somehow 1.5 represents a “tipping point” in the Earth system, which if exceeded, triggers certain feedback mechanisms that cannot be undone.
Either way, it cultivates an atmosphere of fear. And the danger is, if we’ve transgressed 1.5, the feeling mounts that somehow it’s game over, that we’ve failed in our task to manage the risks of climate change. And that, to some at least, will cultivate cynicism, disillusion, and a loss of focus. These are dangerous emotions. They don’t help with clear-eyed thinking around the difficult politics of climate and energy.
Lucy North / PA Images via Getty Images
Q. I think the report the IPCC wrote about 1.5 C in 2018 is really tied up with this discussion. Do you think that report was bound to be misinterpreted?
A. Yeah, the idea of deadlines is a long one in the history of climate advocacy and politics. To me, it’s a pernicious way of thinking about this. There is no cliff edge over which the world’s climate or humanity is going to fall over, whether it’s 1.5, or 2, or 2.5.
The movie that came out a few years ago, Don’t Look Up, used the idea of an asteroid hitting the planet as an allegory for climate change. And that is actually a very bad way of thinking about climate change. It’s not something that will destroy the planet at any particular threshold. It’s an incremental risk — and it’s a relative risk, actually. By relative risk, I mean, one has to think about the things that concern people in the wider context of their life and their aspirations for the future. It’s relative to a pandemic, relative to a nuclear war between two superpowers, relative to having one’s family destroyed by terrorism. So climate change is that type of a problem. It’s not like an asteroid.
Q. Most estimates said that 1.5 C wouldn’t happen until at least the early 2030s. What do you make of these new studies that show the world might be breaching that 1.5 C goal now?
A. The interesting thing about this is, how do we interpret 1.5? Climatologists have always worked with the understanding that climate is something that one can only adequately get a snapshot of over, traditionally, a 30-year period. The IPCC has more recently moved to defining this over a 20-year period. And what these papers are doing is trying to preempt this. Clearly, we haven’t been exceeding 1.5 degrees for 20 years. No one’s claiming that. What these papers are saying is that, in fact, if we’re entering into this 20-year window from 2025 to 2045, we are now entering into this regime where the world’s average temperature will be more regularly exceeding 1.5.
From a scientific point of view, statistical point of view, those studies are fair. I think the danger is the way they get interpreted — that if we have now reached 1.5, suddenly a new category of climate impacts or weather extremes will manifest themselves around the planet.
Of course, the thing that’s going to happen is, “Well, if 1.5 is now in the back mirror, what’s in the front mirror now?” There’s going to be a lot of work done to reconstruct a narrative for those people who think that 1.5 was the be-all and the end-all. There’s now going to have to be very significant work in reeducating and reframing what the future actually holds, if 1.5 is no longer the benchmark.
Q. Is the problem with putting a deadline on climate change partly that it can motivate action in the near-term, but not the long term?
A. I think that’s a good way of making the distinction, perhaps. Climate change is not something that can be arrested in the short term. It is something that is going to be managed in the long term. Putting 1.5 out there at the beginning in Paris in 2015 was not a good move. It may have had some mobilizing power initially, but it doesn’t actually help us achieve the long-term goals of what we need around climate change.
Global temperature isn’t a thing that anyone can control. At least in principle, if you disaggregate this, you can think about particular energy systems — whether they’re fossil-driven or how efficient they are. There are no levers that can directly control global temperature, other than the putative lever of solar geoengineering.

Q. The idea that we’re running out of time to tackle climate change, or that the clock is ticking, is such a common metaphor. Do you think there’s a better way to frame these efforts?
A. Well, yes. We know for a variety of reasons that a world that is 85 to 90 percent dependent on fossil fuels is probably not a good world for the future for all sorts of reasons, climate change being one of them. So one could actually structure some of the politics of this around decarbonization and providing incentives for accelerated decarbonization, but without putting artificial deadlines on it. It’s not as though if we don’t get the world energy system down to 80 percent, 75, 70, 65 percent by certain dates, we’ve somehow lost the battle. At least we’re going in the right direction.
Another way into this is focusing on sustainable development goals. Actually, the things that matter to most people around the relationship that humans have with their physical environment and their social well-being are well captured in the U.N. sustainable development goals, particularly for those who are most exposed to some of the dangers of a changing climate. They are set out with a target to be met by 2030, so you could say there’s a deadline there. But the way in which we think about development is very different from the way we think about climate. No one is saying that we’ve only got five more years in order to achieve any of those development goals. If we don’t, we will continue over the following five or 10 or 15 years to alleviate poverty, increase sanitation, and bring education, particularly for women, up to the standards that people desire.
!function(f,b,e,v,n,t,s)
{if(f.fbq)return;n=f.fbq=function(){n.callMethod?
n.callMethod.apply(n,arguments):n.queue.push(arguments)};
if(!f._fbq)f._fbq=n;n.push=n;n.loaded=!0;n.version=’2.0′;
n.queue=[];t=b.createElement(e);t.async=!0;
t.src=v;s=b.getElementsByTagName(e)[0];
s.parentNode.insertBefore(t,s)}(window, document,’script’,
‘https://connect.facebook.net/en_US/fbevents.js’);
fbq(‘init’, ‘542017519474115’);
fbq(‘track’, ‘PageView’);