An ambitious attempt to develop an early warning system for climate tipping points will combine fleets of drones, cosmic ray detection and the patterns of plankton blooms with artificial intelligence and the most detailed computer models to date.
The UK’s Advanced Research and Invention Agency (Aria), which backs high-risk, high-reward projects, has awarded £81m to 27 teams. The quest is to find signals that forewarn of the greatest climate catastrophes the climate crisis could trigger. Tipping points occur when global temperature is pushed beyond a threshold, leading to unstoppable changes in the climate system.
The programme focuses on two tipping points thought to be at very high risk of being triggered: the collapse of the Greenland ice sheet, which would lead to a huge rise in sea levels, and the collapse of crucial ocean currents in the north Atlantic, which would cause global changes in rainfall and severely damage food supplies.
Scientists have already detected signals indicating that systems such as the Amazon rainforest and the west Antarctic ice sheet are becoming less stable. But researchers are unable to make useful forecasts of when a tipping point is likely to be passed.
Establishing whether that is even possible is the first task for the five-year Aria programme. Tipping points are inherently complex and depend on many factors. Having a chance of success requires much better ocean and ice data, from today and from the past, and better computer models.
“In a similar way to how we use monitoring stations to detect and warn for tsunamis, we’re aiming to establish networks of climate monitoring systems to detect early signs of critical shifts in our climate,” said Gemma Bale and Sarah Bohndiek, the Aria programme directors co-leading the programme. “Through these systems, we can equip decision-makers with the data they need to confront the threat of abrupt climate change head on.”
Scientists have identified at least 16 dangerous tipping points, from northern permafrost collapse to a shift in the west Africa monsoon, and it is possible that some may already have been passed.
The aim of the Aria programme is to create an early warning system that could give a decade-level forecast of tipping points being triggered where possible. Such a warning would be a huge incentive for the world to accelerate climate action, said Prof Tim Lenton at the University of Exeter and the leader of one of the Aria teams. Even if the tipping point could not be stopped, a warning would give precious time for society to prepare for the major impacts.
Lenton said the £81m in total funding was large in research terms: “But it’s a small amount of money compared to the costs of the consequences of crossing one or both of the tipping points.”
The Aria programme targets the Greenland ice sheet and the sub-polar gyre (SPG), which is a component of the globally important Atlantic meridional overturning circulation. Fleets of small, high-speed, vertical takeoff and landing drones, deployed from robotic hangars, will be developed by one project to collect better data in Greenland. Another team is working on autonomous devices that move up and down through the ocean while collecting data on the SPG.
The stakes are high, said Dr Bieito Fernández Castro, at the University of Southampton, who is leading the latter project: “The UK and northern Europe could experience much harsher winters, similar to parts of Canada [if the SPG collapses], while the east coast of the US could see dramatic sea level rises.”
Plankton are the ocean’s pulse, according to another team, and tracking their changes could make them “canaries in the coalmine”. The researchers will attach holographic plankton imaging devices, integrated with artificial intelligence, to container ships, new underwater robots and to filter-feeding ocean giants, such as whales.
Dr Clare Ostle, at the Marine Biological Association and part of the team, said: “By blending cutting-edge technology with decades of global-scale plankton monitoring, we’re creating a system that doesn’t just observe change, but predicts critical ocean shifts.”
The melting rate of the Greenland ice sheet is critical information, and one team will collect the data by developing hardened cosmic-ray neutron sensors suitable for the harsh environment. Another project will deploy a network of sensitive seismic instruments that can measure runoff by listening to the vibrations caused by flowing water.
The project led by Lenton aims to use progress in theory, mathematics and AI to identify the critical measurements needed in the oceans to detect an SPG tipping point, which could then guide the teams in the field. One hypothesis is that a specific three-dimensional pattern of ocean temperature and salinity could be a telltale sign.
Another project will develop highly detailed computer simulations trained on real-world data to test the reliability of potential early warning signals. “We will make use of real-world examples of past tipping points to better understand these events,” said Prof David Thornalley at University College London. More powerful models will be developed by another team, aiming to pinpoint when and where climate tipping points might occur.
“Forecasting tipping points is a formidable challenge,” said Dr Reinhard Schiemann, at the University of Reading. “But the fantastic range of teams tackling this challenge from different angles, yet working together in a coordinated fashion, makes this programme a unique opportunity.”
