🔗 Share this article

The direst possible consequences of the climate crisis for the UK have been outlined by researchers, ranging from a scorching 4C increase in temperatures to a 2-metre increase in sea levels. Another scenario foresees a drop of 6C in temperature following the collapse of key Atlantic Ocean currents, which would massively disrupt food production and energy needs.

Credible Extremes, Not Forecasts

These consequences, certain ones are linked to irreversible climate shifts, are seen as low probability but plausible. The team said that these models filled a gap in risk assessment that had rendered the UK not ready for worst-case results.

"The severe weather events we have outlined are not forecasts, but they are credible," commented Nigel Arnell who oversaw the research. "Britain has been planning in the absence of the tools to assess extreme possibilities. We've now given policymakers what they need to get ready for environmental results they hope never happen, but must not overlook."

A Suite of Severe Conditions Scenarios

Another collection of severe models details the projected severity of harsh climate between now and the year 2100. These indicate that thermometer readings could soar in some months by up to 6C higher than historical levels, while precipitation could be triple standard measurements.

The probability of the worst-case outcomes coming to pass could not be calculated due to uncertainty about what measures will be implemented to tackle climate change and how the planet's climate will behave. This analysis was described as similar to security threat evaluations or resilience checks for financial systems.

Major Possibility Details

• 4C Temperature Rise: Global temperatures rising well above 4C by 2100 could happen if international cooperation collapses or if strong feedback loops like the tropical forests becoming a net carbon source release its enormous store of carbon. This would cause extreme and prolonged heat domes and dry spells affecting the UK in summer.
• Ocean Circulation Failure: A critical sea current, the Atlantic meridional overturning circulation (Amoc), is slowing down and losing stability due to climate change. A full shutdown starting around 2030 would lead to a 6C cooling in the UK. "Farming would struggle enormously and water supplies would be fundamentally reshaped," explained Arnell.
• Accelerated Coastal Flooding: A rise of 2.0-2.2 metres around the UK by 2100 could happen if polar ice in the polar regions disintegrate quickly, inundating seaside communities. Differing from the other scenarios, this possibility is already recognized by infrastructure experts.
• Pollution Paradox: Global averages could also be driven up by about 0.75C if pollution from industry is sharply cut. This counterintuitive effect occurs because aerosol particles from burning coal scatter solar radiation from reaching the ground.

Planning for the Worst

The worst-case scenarios could be applied to guide the development of major projects, such as new towns, energy plants and urban drainage systems. Awareness of these climate risks could also accelerate the transition to cut fossil fuel emissions.

The analysis formulated the severe projections using a combination of real-world events, digital projections and scientific theory. The possibilities exclude broader worldwide issues like the devastation of food supplies and resource wars.

This work was commissioned as part of a national adaptation planning initiative. Independent analyses have warned that not enough attention was being allocated to high-consequence, low-probability risks.

Official experts has said that the UK needs to "prepare for two degrees of warming" and assess the threats for severe warming. Earlier government strategies have been labeled being "insufficient" by environmental groups.

An official statement commented: "Global warming is at the center of this government’s agenda, both preparing for impacts and becoming a clean energy superpower. It is essential that the UK is prepared for the impacts."