A new study demonstrates how a prolonged warming pause or even global cooling may happen in coming years despite increasing levels of atmospheric greenhouse gases — caused by natural climatic variability.
Natural climatic variability has always been a topic that contains a lot of unknowns, but it has been rarely explicitly stated just how little we know about it. Such variability has been habitually underplayed as it was “obvious” that the major driver of global temperature was the accumulation of greenhouse gasses in the atmosphere, with natural variability a weaker effect.
But the global temperature data of this century demonstrate that natural variability has dominated in the form of El Ninos. ‘Doesn’t matter’, came the reply, ‘just wait and the signal of greenhouse warming will emerge out of the noise of natural climatic variability.’ How long will we have to wait for that signal? Quite a long time, according to some researchers as more papers acknowledge that natural climatic variability has a major, if not a dominant influence on global temperature trends.
With the usual proviso concerning climatic predictions there seems to be a growing number of research papers suggesting that the global average temperature of at least the next five years will remain largely unchanged. The reason: natural climatic variability.
Only last week the UK Met Office produced figures suggesting that there is only a 1 in 34 chance that the 1.5°C threshold will be exceeded for the next five year period. Now a new paper by climate modellers extends such predictions, suggesting that because of natural variability the average global temperature up to 2049 could remain relatively unchanged – even with the largest increase in greenhouse gas emissions.
Using two types of computer models in a first of its kind study, Nicola Maher of the Max Planck Institute for Meteorology, Hamburg, Germany, and colleagues writing in Environmental Research Letters looked at the 2019-2034 period concluding that,
We first confirm that on short-term time-scales (15-years) temperature trends are dominated by internal variability. This result is shown to be remarkably robust.”
Looking even further ahead they say that natural variability remains important,
… even out to thirty years large parts of the globe could still experience no-warming due to internal variability,” they add.
The researchers demonstrate internal climatic variability and its importance in driving the climate change that we observe. With a series of maps they visualise both the maximum and minimum global, future trends that could occur on short and mid-term timescales. They also demonstrate clearly the global cooling that could occur under levels of increasing greenhouse gases — caused by internal variability.
The researchers state,
In the short-term all points on the globe could individually experience cooling or no warming, although in a probabilistic sense they are much more likely to warm.”
Looking beyond the short-term they add,
We find that even on the mid-term time-scale a large proportion of the globe could by chance still not experience a warming trend due to internal variability, although this result is somewhat model dependent.”
In the past climate extremists have grasped natural El Ninos and enlisted them as examples of rapid greenhouse global warming. It’s a disingenuous approach that may become harder and harder to do if research like this is any indication.