An ocean system which our mild climate relies on could reach a tipping point by 2040 without us even knowing about it, a report has warned.
Researchers said we are ‘flying blind’ when it comes to the impacts of climate change as we don’t have enough monitoring in place, and we have not addressed the national security risks.
Chaotic and violent impacts could catch us completely off guard like the Covid pandemic, researchers said, with current climate models potentially out of sync with the (worse) reality which could lead to unrest and food shortages.
The UK would be particularly sensitive to changes in ocean currents in the Atlantic, as it is thanks to these that we don’t have a subpolar climate despite being on the same latitude as Canada.
But the report today warned that we are not monitoring the ocean to see how the currents are doing, so we wouldn’t even know the circulation was collapsing until the effects were being felt, giving us little time to prepare.
Collapse might even have been triggered already due to melting Arctic ice, researchers said in the joint report by the Institute for Public Policy Research, Chatham House, the University of Exeter, and the Strategic Climate Risks Initiative.
A study last year warned that that Atlantic Meridional Overturning Circulation (Amoc) could collapse much sooner than previously thought, potentially as early as this decade.
This is the huge system of currents which circulates around the entire Atlantic ocean. Warm water from the tropics cools and evaporates as it moves, becoming saltier and denser. This causes it to sink and head south before it is pulled to the surface and warmed again, repeating the cycle.
On a smaller level, the North Atlantic subpolar gyre (SPG) does much the same thing but in a more local region, which includes the UK.
A weakening of this gyre is a key theory of what led to a ‘Little Ice Age’ in Europe from the 16th to 19th centuries, with ‘profound consequences for the stability of societies,’ the report reads.
Today’s 54-page report argues that climate-security threats ‘should be a core part of national security planning’, and looks at SPG collapse as one of several devastating impacts we need to get our heads round and prepare for.
Lead author Laurie Laybourn told Metro: ‘We don’t exactly know what SPG collapse would do but we have to apply the precautionary principle as these threats are very bad, and say hang on a minute, we need to act with all haste.
‘The climate system might be more delicate than we had thought before, and could respond more violently and chaotically to what fossil fuels are doing to it.’
The wide-ranging report looks at theNorth Atlantic subpolar gyre (SPG) for a section, using it as an example of a potentially abrupt or irreversible change in the climate.
Researchers warned that the there is a 45% chance of it collapsing this century, which could be as soon as 2040.
Its collapse, which might take less than ten years, could ‘disrupt the jet stream, creating more extreme weather, and trigger a collapse of the west African monsoon’, it says, citing previous studies.
It would be likely to cause more extreme weather patterns with hotter summers and colder winters, impacting the ability to farm and grow crops, and damaging infrastructure and public health.
‘There is now a range of evidence to suggest that even at the present stage of climate change, the SPG appears destabilised with potential for tipping,’ the report says.
With such potentially huge and imminent consequences, you’d think it would be a priority to keep close tabs on the subpolar gyre, but we’re not, and nor is any other country.
Mr Laybourn said it isn’t even clear what the best ways of monitoring it would be, but could potentially involve sensors in the ocean to see how circulation is changing, and the movement of meltwater in polar regions.
Climate tipping points
Tipping points in climate change are changes which we cannot reverse, and which could have devastating impacts. Although they may begin gradually, they can suddenly shift abruptly, and will affect other aspects of the climate too.
Some examples of tipping points are:
- Collapse of large ocean current systems
- Melting of ice caps
- Transformation of the Amazon rainforest to grassland
- Death of coral reefs
The report explains them like this: ‘Think about leaning back on a chair until it suddenly falls backwards. That moment is the tipping point. Your previous state – balancing precariously – has been replaced by a new state: lying on the floor.
‘Components of the climate system can experience a similar dynamic, ‘falling over’ at varying speeds depending on the system in question.
‘Some, like the collapse of ice sheets, could play out over centuries. Others, including the tipping points we explore below, can play out over a matter of years: timescales with direct relevance to security decision-making.’
‘Due to the speed at which SPG collapse could play out, it is critical to have early warning to support rapid adaptation efforts if collapse were to occur,’ the report says.
We have signals intelligence for terror attacks, and global health monitoring for potential pandemics and act accordingly when warnings arise, he said, but we’re not prepared enough for the effects of climate tipping points.
On a more optimistic note, he said there ‘is a movement across the world in national security in government to face up to the threat we now see’.
The US and and Australian governments are among those to have launched reviews into the effect of climate change on national security, and he is hopeful the UK will do the same.
Improved risk assessments would ‘highlight how the threats to the UK from climate change are far more severe and disruptive than is generally understood’ by both politicians and the general public, the report said.
‘Cascading impacts will escalate, and tipping points might be triggered. This reality is hard to face – a potentially profound dislocation of expectation,’ it says.
‘But it does not mean that climate action is futile. The opposite is true. Whatever climate change throws at the UK, the unavoidable will have to be managed.’
‘The Security Blind Spot: Cascading climate impacts and tipping points threaten national security’ can be read in full here.
Get in touch with our news team by emailing us at webnews@metro.co.uk.
For more stories like this, check our news page.
MORE : Map shows where 20 flood warnings are in place across UK
MORE : Hurricane Milton live: Millions told to flee as ‘life or death’ warning issued
MORE : Does ‘gay face’ actually exist? Experts have brilliant response to pseudo-science
Get your need-to-know
latest news, feel-good stories, analysis and more
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
