5 min read

A Year Above 1.5°C

A Year Above 1.5°C

Early in February, the planet passed yet another milestone: the last twelve months were spent at 1.5°C above pre-industrial levels. 1.5°C, for new subscribers and newborns, is the threshold at which scientists agree we risk knocking over various climatic tipping points–tipping points which cannot be un-knocked and will only exacerbate climate change. If you've been a reader of When/If for a while, you may remember that I used to write posts talking about this stuff happening in our future. You may have noticed that lately I write about how they're happening now. When/If is not even 4 years old. We are blowing past expectations.

A year past 1.5°C in 2023-2024 (indeed, we're sitting close to 2°C right now) is quite a bit sooner than folks imagined this would happen–it's earlier than I had figured, and I'm a doomer. But, to be clear, we have not crossed the 1.5°C threshold as it is defined; we are just standing within that threshold. There is no broadly accepted point at which science says we have crossed the threshold, but it is agreed that it's likely several years spent over 1.5°C. It is entirely possible, probable even, that we will slip back below 1.5°C as El Niño fades and we move into the cooler period of La Niña. A year spent in the threshold of existential danger is not, however, something we should ignore.

Tipping Point In Peril

At almost the same time as articles came out about our dalliance with 1.5°C, others were published following a recently released study regarding AMOC, or the Atlantic Meridional Overturning Circulation–the conveyor belt in the Atlantic of warm, oxygenated water heading north, cooling and descending to return to where it began. This study comes on the heels of another from July last year, which concludes that AMOC is close to reaching its tipping point. AMOC is at its weakest in a thousand years, and there are no inputs into this system currently that can revert its course. Climate change, without fail, will continue to weaken AMOC and almost certainly cause it to cease its flow completely. The report getting passed around in the media today reifies that it will collapse in its current trajectory.

By now I've talked about AMOC roughly ten or fifteen times, but it bears repeating that this mechanism is immensely important, and without it the world as we know it ceases to exist. Without AMOC, the East Coast will see up to a meter in sea-level rise. Ecosystems across the ocean will collapse, which will quickly put immense pressure on coastal communities that rely on fishing for income and, naturally, everyone that relies on fishing for food. The Atlantic itself will begin to die, with vast swaths of anoxic water expanding and killing almost all life within it. Europe and the UK will get up to 10°C colder, as much of those regions get their relatively warm weather from AMOC carrying warm equatorial water north. As you might expect, this means that warm water stays in the equatorial south, which will be warmed commensurately. It's also theorized that the seasons in the Amazon will flip–the sort of thing you only hear about in sci-fi books. This would result in a catastrophic loss of flora and fauna, and potentially drive the Amazon itself past its own tipping point. Parts of Europe will become more arid, making breadbaskets like Ukraine much less reliable. The study from 2023 predicts that AMOC could begin to collapse as soon as 2025. Most scientists find this to be a bit alarmist.

Why That Seems Likelier Than It Did A Year Ago

Picture of a tweet discussing the all-time record high global sea surface temperatures, accompanied by a chart showing the average temperatures over the years.

For much of last year, the world's oceans were breathtakingly warmer than previous years. If the start of 2024 is any indication (which it isn't, necessarily–La Niña and all), the oceans will get that much hotter still. This massive influx of heat is eroding critical ice formations in Antarctica and Greenland, which will continue to weaken and eventually collapse AMOC.

Oceans are a great indicator of planetary health. They are the foundation of the world's ecosystems, enormous CO2 sinks, and they absorb most of the heat the planet takes in. The fact that they are rather suddenly drastically hotter than ever before should be reason enough to sound all the alarms. Taking nothing else into consideration, this increase in temperature plays havoc on ocean life; recent related plagues include miles-wide rafts of rotting seaweed, algal blooms that can choke life from coastlines, and coral bleaching that ruins local food chains. All of this–even the little stuff, matters. Our oceans have not been healthy in a long time, and we have abused them for their resources to a breaking point.

All indicators suggest criticality. I wouldn't bet on AMOC collapsing next year or the year after, but we will continue to see signs that it is weakening, and that will further exacerbate weather issues. What I would bet on is that the longer projections of its demise get blown out as it collapses by, say, 2035. This train is accelerating, and it will only pick up speed–indeed, it will get damn near exponentially faster.

Get Serious About Your Preps

It's well past time to take climate change seriously. If your only engagement with preparedness thus far is subscribing to this newsletter, I beseech you: do more. While you may not feel apocalyptic effects anytime soon, such an event falling on your head is not the time after which you should make preparations–you should be doing this beforehand. Any prep is better than no prep, and the basics do the most. Stock up on non-perishable food; store as much water as you possibly can; buy first-aid kits, stock up on common medicines like ibuprofen and antihistamines. If you live in a region susceptible to inclement weather–like fires or floods–plan escape routes and share these with your family. Make copies of important documents and put them in a go-bag.

Learn how to do the things every human used to know how to do: garden, cook, make simple repairs to clothing. Learn how to stitch a wound and perform CPR. If you find a niche you like, specialize and share your skills with your people. More than anything, more than any can of beans or gallon of water or gadget, you need community. Find yours. Make it. Talk to friends, talk to family. How we fail as a species is by sleepwalking into the fire. Don't be a part of that problem.

I want to share a resource that I've been making use of and enjoying (weird to say that–you know what I mean): American Resiliency is a YouTube account that covers climate change data for the United States in a calm, matter-of-fact way in much greater detail than I do it. For those of you hungry for more scientific and data-driven discussions, this is the channel for you.