James Stewart

These instruments have special sensors attached to them, which measure things like ocean current speed, temperature, salinity and direction of the water crossing the arrays.

These instruments have special sensors attached to them, which measure things like ocean current speed, temperature, salinity and direction of the water crossing the arrays.

One of the major things to keep an eye on in relation to when this collapse might be imminent, the sort of alarm clock if you will, is the flow of water in the Atlantic, which has been measured with the RAPID project since 2004. The other measurements help us monitor water mixing during winter in the North Atlantic and Nordic seas.

One of the major things to keep an eye on in relation to when this collapse might be imminent, the sort of alarm clock if you will, is the flow of water in the Atlantic, which has been measured with the RAPID project since 2004. The other measurements help us monitor water mixing during winter in the North Atlantic and Nordic seas.

One of the major things to keep an eye on in relation to when this collapse might be imminent, the sort of alarm clock if you will, is the flow of water in the Atlantic, which has been measured with the RAPID project since 2004. The other measurements help us monitor water mixing during winter in the North Atlantic and Nordic seas.

If the deep mixing starts to decline a lot, that could be an early indicator that we are approaching a tipping point. Now, whilst there are some signs of this, as we've shown throughout this video, we don't have enough data yet to be sure when that might be. Last big final question. We know the AMOC has collapsed before and it's come back again. So could it not just do that again if it collapses?

If the deep mixing starts to decline a lot, that could be an early indicator that we are approaching a tipping point. Now, whilst there are some signs of this, as we've shown throughout this video, we don't have enough data yet to be sure when that might be. Last big final question. We know the AMOC has collapsed before and it's come back again. So could it not just do that again if it collapses?

If the deep mixing starts to decline a lot, that could be an early indicator that we are approaching a tipping point. Now, whilst there are some signs of this, as we've shown throughout this video, we don't have enough data yet to be sure when that might be. Last big final question. We know the AMOC has collapsed before and it's come back again. So could it not just do that again if it collapses?

Well, sort of, maybe. Let's say it did collapse. Even if that fresh water input into the oceans from ice melting decreases to current levels, the AMOC may still remain in a collapsed state. The ability of the system to not return to the initial state once the forcing is reversed is referred to as hysteresis.

Well, sort of, maybe. Let's say it did collapse. Even if that fresh water input into the oceans from ice melting decreases to current levels, the AMOC may still remain in a collapsed state. The ability of the system to not return to the initial state once the forcing is reversed is referred to as hysteresis.

Well, sort of, maybe. Let's say it did collapse. Even if that fresh water input into the oceans from ice melting decreases to current levels, the AMOC may still remain in a collapsed state. The ability of the system to not return to the initial state once the forcing is reversed is referred to as hysteresis.

Interestingly, the UK's Met Office models show that there may be a temporary resilience period in the AMOC after a threshold has been crossed, during which the AMOC could still recover if the freshwater input is reversed rapidly. In one Met Office model they use, the AMOC recovers if freshwater inflow ceases after 20 years, but not if it ceases after 50 years.

Interestingly, the UK's Met Office models show that there may be a temporary resilience period in the AMOC after a threshold has been crossed, during which the AMOC could still recover if the freshwater input is reversed rapidly. In one Met Office model they use, the AMOC recovers if freshwater inflow ceases after 20 years, but not if it ceases after 50 years.

Interestingly, the UK's Met Office models show that there may be a temporary resilience period in the AMOC after a threshold has been crossed, during which the AMOC could still recover if the freshwater input is reversed rapidly. In one Met Office model they use, the AMOC recovers if freshwater inflow ceases after 20 years, but not if it ceases after 50 years.

This gives a 20 to 50 year temporary resilience, but the temporary resilience period would be lower if fresh water was added at a higher rate. The last time it collapsed it took a thousand years to recover, though the pass is not a direct analogue because there is also massive CO2 forcing this time.

This gives a 20 to 50 year temporary resilience, but the temporary resilience period would be lower if fresh water was added at a higher rate. The last time it collapsed it took a thousand years to recover, though the pass is not a direct analogue because there is also massive CO2 forcing this time.

This gives a 20 to 50 year temporary resilience, but the temporary resilience period would be lower if fresh water was added at a higher rate. The last time it collapsed it took a thousand years to recover, though the pass is not a direct analogue because there is also massive CO2 forcing this time.

CO2 is already higher than at any time in the last 15 million years and we are still in an ice age after all.

CO2 is already higher than at any time in the last 15 million years and we are still in an ice age after all.

CO2 is already higher than at any time in the last 15 million years and we are still in an ice age after all.