If the Interdecadal Pacific Oscillation (IPO) hasn’t yet moved into a positive phase, though, the 1.5° Celsius threshold will still be passed by 2031 or so, according to the research.
I put “barrier” in quotes above because the Paris climate talks agreement has always been toothless, and seems to have been mostly about positive PR for the countries in question (to make it look like something was being done) more than anything else. In other words, I think they were another example of the way that many things in the “modern” world have devolved to simply being a matter of obnoxious showiness and mindless noise, rather than as a serious intent to comprehend and enact change (with all of the costs, sacrifices, and resistance/conflicts that go along with that).
With regard to the new research, which is detailed in a paper published in the journal Geophysical Research Letters, the general takeaway is that if the positive phase of the IPO has now started, as appears to be the case, then a sharp increase in the rate of global average temperature rise is in store for the next decade or so.
The current warming trend is occurring despite the fact that the IPO has been in the negative phase of its cycle since 1999 — typically the negative phase of the IPO cycle results in cooling temperatures (or in the case of the last few 50 or so years, a stalled rise in temperatures). As an example here, the last time the IPO was in a negative phase (previous to the current one) was during 1947–1976.
“Even if the IPO remains in a negative phase, our research shows we will still likely see global temperatures break through the 1.5° Celsius guardrail by 2031,” commented lead author Dr Ben Henley.
“If the world is to have any hope of meeting the Paris target, governments will need to pursue policies that not only reduce emissions but remove carbon from the atmosphere. Should we overshoot the 1.5°C limit, we must still aim to bring global temperatures back down and stabilise them at that level or lower.”
So, the general takeaway, according to the researchers, is that cost-effective carbon capture technologies/approaches will be necessary if temperatures are to remain low enough for anything like the current industrial civilization to survive. If temperatures rise high enough, and cause enough climatic turbulence, of course, then people may well not stick around at all (there are massive social and geopolitical problems looming as a result of rising resource extraction costs, soil erosion, desertification, pollution, species extinctions + biodiversity/genetic loss, etc., as well, it should be remembered).
The press release about the new climate research provides more: “The IPO has a profound impact on our climate because it is a powerful natural climate lever with a lot of momentum that changes very slowly over periods of 10-30 years. During its positive phase the ocean temperatures in the tropical Pacific are unusually warm and those outside this region to the north and south are often unusually cool. When the IPO enters a negative phase, this situation is reversed.
“In the past, we have seen positive IPOs from 1925–1946 and again from 1977–1998. These were both periods that saw rapid increases in global average temperatures. The world experienced the reverse — a prolonged negative phase — from 1947–1976, when global temperatures stalled. A striking characteristic of the most recent 21st Century negative phase of the IPO is that on this occasion global average surface temperatures continued to rise, just at a slower rate.”
“Although the Earth has continued to warm during the temporary slowdown since around 2000, the reduced rate of warming in that period may have lulled us into a false sense of security. The positive phase of the IPO will likely correct this slowdown. If so, we can expect an acceleration in global warming in the coming decades,” Dr Henley concluded.
“Policy makers should be aware of just how quickly we are approaching 1.5° Celsius. The task of reducing emissions is very urgent indeed.”
I’ll depart from Dr Henley’s viewpoint here by noting that, whether or not policy makers are “aware” of the problem is less the issue than whether or not there are any/many solutions that are politically acceptable.
The truth, to my eyes, is that most people — “conservative,” “liberal,” or otherwise — are completely unwilling to give up the incredibly resource- and carbon-intensive modern way of living. And, thus, there are no ways of addressing the looming climate problems that are acceptable to the populace(s) at large. Once the impacts start hitting in earnest over the next few decades, that may well change…