The atmosphere and oceans are warming rapidly, and will continue to warm for many decades. But this is hardly the first time our planet has been this warm, though it probably is the most rapid heat up ever.
So, one way to think about it is that the planet is heading for “Pleistocene” conditions in a couple of decades, and “Miocene” conditions in fifty years or so [2]. Obviously, there won’t be Mammoths or sabre tooth cats, alas, but the overall environment could well resemble these ancient periods.
This is the idea behind a study of paleoclimates in the British Isles [1]. The research used fossil pollen to parametrize a climate model. The models infer the Mean Annual Temperature and Mean Annual Precipitation, as well as related statistics.
The results indicate that Britain was warm and wet, warmer and wetter than now (as expected). But conditions in Britain were milder than continental Europe.
The researchers argue that these reconstructions of past climate suggest likely future conditions in Britain. So, for instance, these results suggest that the UK may experience mildly warmer and wetter weather in the coming century.
This sort of modelling is iffy, of course. The fossil pollen records are sparse and hard to interpret precisely. In addition, the models developed from contemporary data may or may not apply to earlier periods, it’s hard to know. So, iffy data plus iffy models equals, what?
On the one hand, the results are quite plausible, which seems to indicate that the models are OK and the data is good enough to make sense.
On the other hand, saying that the overall temperature of the planet is similar to the Miocene is hardly a complete picture. We know that the climate of Britain and Northern Europe are strongly influenced by the Atlantic currents. If the currents change dramatically, then Britain and Europe could experience a much colder and drier climate, regardless of global averages.
The results of this study seem to imply that the currents must have been similar to now in the Miocene, at least during the warm periods studied. If so, then those periods cannot represent what the climate will be like in the event of a major excursion of the Atlantic circulation.
In any case, these findings scarcely change our basic understanding: human activities are modifying the planet rapidly in ways that we don’t completely understand but know are likely to be harmful to humans and other living things.
- M. E. Gibson, J. McCoy, J. M. K. O’Keefe, N. B. Nuñez Otaño, S. Warny, and M. J. Pound, Reconstructing Terrestrial Paleoclimates: A Comparison of the Co-Existence Approach, Bayesian and Probability Reconstruction Techniques Using the UK Neogene. Paleoceanography and Paleoclimatology, 37 (2):e2021PA004358, 2022/02/01 2022. https://doi.org/10.1029/2021PA004358
- Matthew Pound and Martha Gibson, We reconstructed Britain of millions of years ago to see what climate breakdown will involve, in Resilience, February 11, 2022. https://www.resilience.org/stories/2022-02-11/we-reconstructed-britain-of-millions-of-years-ago-to-see-what-climate-breakdown-will-involve/
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