James Stewart

There's a rise in greenhouse gas emissions and arctic amplification. There's also an increasingly enhanced water cycle, intensified by more energy from the sun, which creates more extreme weather like floods and droughts. There's also more evaporation in the subtropics and more precipitation in the high latitudes. Now these things are all happening before we've ever mentioned melting sea ice.

And here comes the big one. The Greenland ice sheet is melting at a rate of around 270 billion tonnes per year, and this is what makes the water less and less salty.

And here comes the big one. The Greenland ice sheet is melting at a rate of around 270 billion tonnes per year, and this is what makes the water less and less salty.

And here comes the big one. The Greenland ice sheet is melting at a rate of around 270 billion tonnes per year, and this is what makes the water less and less salty.

The fresh water dilutes the salty water, and this is salt advection feedback, a positive feedback mechanism that affects the strength of the AMOC, as the major tipping point that ultimately leads to a slowdown or even collapse of the AMOC. In 1961, US oceanographer Henry Stommel recognized how the Atlantic water's salinity leads to an AMOC tipping point.

The fresh water dilutes the salty water, and this is salt advection feedback, a positive feedback mechanism that affects the strength of the AMOC, as the major tipping point that ultimately leads to a slowdown or even collapse of the AMOC. In 1961, US oceanographer Henry Stommel recognized how the Atlantic water's salinity leads to an AMOC tipping point.

The fresh water dilutes the salty water, and this is salt advection feedback, a positive feedback mechanism that affects the strength of the AMOC, as the major tipping point that ultimately leads to a slowdown or even collapse of the AMOC. In 1961, US oceanographer Henry Stommel recognized how the Atlantic water's salinity leads to an AMOC tipping point.

In other words, the AMOC flows because the Northern Atlantic is salty, and it's salty because the AMOC flows. It's chicken and egg, or in more technical terms, a self-sustaining feedback effect, which works the other way around as well. If the northern Atlantic becomes less salty because of an inflow of fresh water, the water becomes less dense and the AMOC slows down.

In other words, the AMOC flows because the Northern Atlantic is salty, and it's salty because the AMOC flows. It's chicken and egg, or in more technical terms, a self-sustaining feedback effect, which works the other way around as well. If the northern Atlantic becomes less salty because of an inflow of fresh water, the water becomes less dense and the AMOC slows down.

In other words, the AMOC flows because the Northern Atlantic is salty, and it's salty because the AMOC flows. It's chicken and egg, or in more technical terms, a self-sustaining feedback effect, which works the other way around as well. If the northern Atlantic becomes less salty because of an inflow of fresh water, the water becomes less dense and the AMOC slows down.

It brings less salt to the region, which then slows down the AMOC further. One of the most interesting things in this crazy cycle of ocean systems and currents is that the AMOC has a bit of a track record of being less than stable. In other words, it's collapsed before. And its collapse has historically been linked to some pretty extreme climate events.

It brings less salt to the region, which then slows down the AMOC further. One of the most interesting things in this crazy cycle of ocean systems and currents is that the AMOC has a bit of a track record of being less than stable. In other words, it's collapsed before. And its collapse has historically been linked to some pretty extreme climate events.

It brings less salt to the region, which then slows down the AMOC further. One of the most interesting things in this crazy cycle of ocean systems and currents is that the AMOC has a bit of a track record of being less than stable. In other words, it's collapsed before. And its collapse has historically been linked to some pretty extreme climate events.

I sometimes forget that we're still in an ice age, albeit an interglacial one, but the climate during the last glacial period was also far from stable. To give us a clue into past AMOC behaviour, we can examine some dramatic climate changes that have happened in the recent past. Recent that is from a paleoclimate perspective, the last 100,000 years or so.

I sometimes forget that we're still in an ice age, albeit an interglacial one, but the climate during the last glacial period was also far from stable. To give us a clue into past AMOC behaviour, we can examine some dramatic climate changes that have happened in the recent past. Recent that is from a paleoclimate perspective, the last 100,000 years or so.

I sometimes forget that we're still in an ice age, albeit an interglacial one, but the climate during the last glacial period was also far from stable. To give us a clue into past AMOC behaviour, we can examine some dramatic climate changes that have happened in the recent past. Recent that is from a paleoclimate perspective, the last 100,000 years or so.

One thing we know from studying the paleoclimate is that some of the most abrupt and striking temperature changes are periods of abrupt warming followed by a period of slow cooling that occurred during the last ice age. They were likely caused by instability in the amok. This graph shows temperature reconstructions from ocean sediments and Greenland ice over the last 60,000 years.

One thing we know from studying the paleoclimate is that some of the most abrupt and striking temperature changes are periods of abrupt warming followed by a period of slow cooling that occurred during the last ice age. They were likely caused by instability in the amok. This graph shows temperature reconstructions from ocean sediments and Greenland ice over the last 60,000 years.

One thing we know from studying the paleoclimate is that some of the most abrupt and striking temperature changes are periods of abrupt warming followed by a period of slow cooling that occurred during the last ice age. They were likely caused by instability in the amok. This graph shows temperature reconstructions from ocean sediments and Greenland ice over the last 60,000 years.

The green line here refers to sediment data, and the blue line refers to ice core data. What's interesting is as the blue and green lines drop dramatically throughout the time period, they coincide with Heinrich events, marked red, and DO events, which are numbered. This demonstrates an unstable AMOC in all likelihood led to these dramatic spikes.