Crop yields in Great Britain will PLUMMET if climate change causes vital ocean currents to collapse
Crop yields in Great Britain PLUMMET as climate change causes vital sea currents from collapsing, resulting in a temperature drop of 6 ° F and reduced rainfall
- The Atlantic Meridional overthrowing circulation brings heat from the tropics
- This makes Britain warmer and wetter than it would otherwise be
- The collapse of this important circulation pattern would make the UK colder and drier
- Such a shift would reduce the available land for crop growth by about a quarter
- In this worst-case scenario, realizable values would fall by around £ 346 million per year
Crop yields in Great Britain will drop if climate change causes vital ocean currents from collapsing – the temperature drops by 6 ° F – a study has shown.
The so-called Atlantic Meridional Overturning Circulation (AMOC) brings heat out of the tropics, making Britain warmer and wetter than it would otherwise be.
Experts from the University of Exeter discovered that while an exciting UK would see food production, the collapse of the AMOC would paralyze arable farming.
In this scenario, which would see reduced rainfall, the land area suitable for crops would shrink by a quarter, reducing yields by around £ 346 million per year.
Such a collapse – which experts call a “tipping point” of climate change – would make Britain cooler, drier, and unsuitable for many crops, researchers found.
Reduced rainfall would be the biggest problem – and although irrigation could be used to compensate for this, the experts said the cost would be prohibitive.
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Crop yields in Great Britain will decrease if climate change causes vital sea currents from collapsing – the temperature drops by 6 ° F – a study has been found (stock image)
“If the AMOC collapsed, we would expect much more dramatic change than currently expected due to climate change,” said mathematician Paul Ritchie of the University of Exeter.
“Such a collapse would reverse the effects of warming in Great Britain, resulting in an average temperature drop of 3.4 ° C [6.1°F] and that led to a significant reduction in rainfall of 123 mm [4.8 inches] during the growing season, “he added.
“These changes, especially drying, can make most land unsuitable for arable farming.”
According to experts, the AMOC – of which the Gulf Stream is a part – is one of the reasons why the average temperatures in Britain are generally warmer than in many places at comparable latitudes.
The cool south of Alaska and Moscow, for example, are at higher latitudes than Edinburgh in the UK.
In their research, the researchers investigated a “rapid and early” collapse of the AMOC.
Although this scenario is currently considered a ‘low probability’, the AMOC has been weakened by an estimated 15 percent over the past 50 years.
At worst, scenarios should be considered when calculating risks, said Tim Lenton, Earth Scientist at the University of Exeter.
“Any risk assessment should get a grip on the major consequences if such a turning point is reached, even if it is a low-probability event,” he added.
“The purpose of this detailed study was to discover how great the impact of AMOC collapse could be.”
The collapse of the AMOC – which experts call a “turning point” in climate change – would make Britain cooler, drier, and unsuitable for many crops, researchers found
Previous work by the team had warned of a possible “cascade” of interrelated climate tipping points.
Professor Lenton said the new study reinforces the idea that “we would be wise to act now to minimize the risk of circumventing climate tipping points.”
Growing crops is generally more profitable than using land as a pasture for livestock farming, but much of Northern and Western Great Britain is not suitable for arable farming.
“With the land area suitable for arable farming expected to fall from 32 percent to 7 percent below the collapse of AMOC, we could see a significant reduction in the value of agricultural production,” said paper author and environmental economist Ian Bateman.
“In this scenario, we estimate a decrease of £ 346 million a year – a reduction in the net value of British agriculture by more than 10 percent.”
Professor Bateman noted that there is a common expectation that moderate warming will stimulate Britain’s agricultural production.
“It is important to note that the wider effects for the UK and beyond will be very negative as import costs rise sharply and the cost of most goods increases,” he said.
Although the team focused their current study on agriculture, the collapse of the AMOC and the resulting fall in temperature could also lead to many other economic disadvantages for the UK, the team warned.
The full findings of the study were published in the journal Organic food.
WHAT IS THE GLOBAL OCEAN Conveyor Belt?
When it comes to regulating the global climate, the circulation of the Atlantic plays a key role.
This is due to a constantly moving system of deep water circulation, also known as the Global Ocean Conveyor Belt, which sends warm, salt Gulf Stream water to the North Atlantic, where it releases heat to the atmosphere and warms Western Europe.
The cooler water then sinks to great depths and travels all the way to Antarctica and eventually circulates back to the Gulf Stream.
When it comes to regulating the global climate, the circulation of the Atlantic plays a key role
This movement is fed by thermohaline currents – a combination of temperature and salt.
It takes 1000 years for water to complete an uninterrupted journey around the world.
Researchers believe that when the North Atlantic began to heat up towards the end of the Little Ice Age, fresh water disrupted the system, called the Atlantic Meridional Reversing Circulation (AMOC).
Arctic sea ice and ice caps and glaciers around the Arctic began to melt and formed an enormous natural tap of fresh water that flowed into the North Atlantic.
This enormous influx of fresh water diluted the surface water, making it lighter and less able to sink, which delayed the AMOC system.
Researchers discovered that the AMOC has been weakening faster since 1950 in response to recent global warming.