Can we predict Climate Tipping Points?

Researchers are trying to find out whether we can predict tipping points in advance so that we can try and avoid crossing them in the first place.

One way to find out where tipping points may be is by studying past climate records, which show us when tipping points may have happened in the past. There are many times in geological past (for example at the end of ice age glacials, when ice first grew on Antarctica around 34 million years ago, and the rapid warming during the Palaeocene-Eocene Thermal Maximum around 55 million years ago) where very gradual changes give way to a very rapid change in the climate which may be examples of tipping points being reached.

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Temperature records showing rapid warming at the end of Ice Age glacial periods – Can you Spot The Tips? Image: CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=466270

Computer models allow us to find out how big complex systems like the climate may have tipping points. It’s very difficult to understand a system as complex as the climate just by observing it in realtime, and so building a numerical model is a useful way to try and work out how it works by building our own simplified virtual version of the climate or some specific part of it. We can then try out lots of different scenarios pushing the model climate in different ways to see if certain scenarios trigger rapid change because of unknown tipping points.

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Climate Models can be driven by different scenarios to see if they contain hidden tipping points that trigger rapid change. Image By NOAA – http://celebrating200years.noaa.gov/breakthroughs/climate_model/welcome.html http://www.gfdl.noaa.gov/pix/model_development/climate_modeling/climatemodel.png, Public Domain, https://commons.wikimedia.org/w/index.php?curid=18426462

Statistics can be used to look for ‘Early Warning Signals’ of nearby tipping points in climate data. When a system like the climate becomes less stable and resilient near a tipping point, its behaviour becomes much more erratic and it recovers more slowly from small knocks. Think of it like a spinning top – it’s stable for a while, but as it slows down it starts wobbling a lot and eventually tips over (see video below). This behaviour can be picked up using statistical analysis, and can be seen before many past climate shifts and in modern ecosystems before observed ecosystem shifts.


Youtube video from user archer6817j – mute reccomended

Ecosystem Canaries may give us an early warning to ecosystem collapse. Rare species may be the first to disappear in a stressed ecosystem approaching a transition, but may not be noticed if they’re seen as not important in themselves. But these species can act like the canary in a coal mine, and can give us an early warning to change our behaviour before the ecosystem tipping point is reached.

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A coalminer’s canary. Can other species act as an early warning for tipping points in a whole ecosystem? Image: Don McPhee for the Guardian

Research on Climate Tipping Points and Early Warning Signals is currently ongoing and making progress. The ReCoVER network is currently funding cutting-edge tipping point research at the University of Southampton and elsewhere on looking for early warning signals in past climate records and other settings. Visit their website to find out more about the ReCoVER network and the research they support.

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