From the “worse than we thought” department comes this new climate model, but at least they acknowledge the pause.
The next few years could be “anomalously warm”, according to a new study.
Researchers have developed a mathematical model to predict how average global surface air temperatures will vary over the next few years.
The results suggest that the period from 2018 to 2022 could see an increased likelihood of extreme temperatures.
The findings are published in the journal Nature Communications.
The warming caused by emissions of greenhouse gases like CO2 is not increasing at a perfectly steady rate.
In the early years of the 21st Century, scientists pointed to a hiatus in warming. But several analyses show that the five warmest years on record all have taken place since 2010.
These variations from year-to-year do not affect the long-term trend in warming temperatures.
Now, a new method for trying to predict global temperatures suggests the next few years will be hotter than expected.
Rather than using traditional climate simulation techniques, Florian Sévellec, from the CNRS in Brest, France, and Sybren S Drijfhout, from the University of Southampton, developed a statistical method to search through simulations of climatic conditions in the 20th and 21st Century and look for situations that are comparable to the present day.
The team then used these climatic “analogues” to deduce future possibilities.
In particular, the anomalous warmth predicted over the next few years is due to a low probability of intense cold climatic events.
Once the algorithm is “learned” (a process which takes a few minutes), predictions are obtained in a few hundredths of a second on a laptop. In comparison, supercomputers require a week using traditional simulation methods.
Gabi Hegerl, professor of climate system science at the University of Edinburgh, who was not involved with the study, said: “The authors have tried to predict whether global climate variability will make the next years warmer or cooler overall than the mean warming trend. They have skilfully used worldwide climate model data for previous years to calculate probabilities for the next few years.
“The findings suggest it’s more likely we’ll get warmer years than expected in the next few years.
Full article here
As noted further in the article, the result is “purely statistical”, so take it with a grain of salt, because I suspect the “learning” part of the algorithm doesn’t handle long-term natural variation well at all, just like the short term memory of humans often can’t recall the intensity of weather events in the far past. Of course, humans programmed this, so…
UPDATE: Here’s the paper:
A novel probabilistic forecast system predicting anomalously warm 2018-2022 reinforcing the long-term global warming trend
In a changing climate, there is an ever-increasing societal demand for accurate and reliable interannual predictions. Accurate and reliable interannual predictions of global temperatures are key for determining the regional climate change impacts that scale with global temperature, such as precipitation extremes, severe droughts, or intense hurricane activity, for instance. However, the chaotic nature of the climate system limits prediction accuracy on such timescales. Here we develop a novel method to predict global-mean surface air temperature and sea surface temperature, based on transfer operators, which allows, by-design, probabilistic forecasts. The prediction accuracy is equivalent to operational forecasts and its reliability is high. The post-1998 global warming hiatus is well predicted. For 2018–2022, the probabilistic forecast indicates a warmer than normal period, with respect to the forced trend. This will temporarily reinforce the long-term global warming trend. The coming warm period is associated with an increased likelihood of intense to extreme temperatures. The important numerical efficiency of the method (a few hundredths of a second on a laptop) opens the possibility for real-time probabilistic predictions carried out on personal mobile devices.