🔗 Share this article

The most severe projected effects of the global heating for the UK have been detailed by scientists, including a scorching 4C rise in average temperatures to a 2-metre rise in sea levels. Another scenario foresees a decline of 6C in temperature following the collapse of key Atlantic Ocean currents, which would massively disrupt farming and power requirements.

Credible Outcomes, Not Guarantees

These effects, certain ones are connected to irreversible climate shifts, are seen as low probability but possible. The team explained that these scenarios filled a gap in risk assessment that had left the UK unprepared for catastrophic possibilities.

"The severe weather events we have mapped are not forecasts, but they are possible," commented Nigel Arnell who directed the research. "The UK has been formulating policy in the absence of the frameworks to test against extreme possibilities. We've now given policymakers what they need to plan for environmental results they pray never occur, but dare not dismiss."

A Suite of Harsh Climate Possibilities

A further series of dire projections details the projected severity of extreme weather between now and the year 2100. These indicate that thermometer readings could soar in certain periods by up to 6C higher than average, while rainfall could be triple typical amounts.

The likelihood of the extreme scenarios happening remains uncertain due to uncertainty about what action will be implemented to tackle global warming and how the Earth's systems will react. This approach was likened to security threat evaluations or resilience checks for financial systems.

Major Possibility Details

• Severe Heating: Planetary heating exceeding 4C by 2100 could transpire if climate action fails or if strong feedback loops including the tropical forests perishing unleash its huge repository of carbon. This would result in extreme and prolonged heatwaves and droughts hitting the UK in summer.
• AMOC Shutdown: A key circulation system, the North Atlantic current, is weakening and losing stability due to ocean warming. A full shutdown starting around 2030 would lead to a six-degree temperature drop in the UK. "Crop production would struggle enormously and freshwater availability would be fundamentally reshaped," noted Arnell.
• Rapid Sea Level Rise: A rise of 2.0-2.2 metres around the UK by 2100 could occur if glaciers in Greenland and Antarctica disintegrate quickly, submerging coastal cities and towns. In contrast to the other scenarios, this risk is already understood by infrastructure experts.
• Pollution Paradox: Global averages could also be increased by about 0.75C if airborne particulates is rapidly cleaned up. This unexpected result occurs because aerosol particles from burning coal block sunlight from reaching the ground.

Building Resilience Against the Worst

The worst-case scenarios could be utilized in planning the development of critical national infrastructure, including expanded cities, nuclear power stations and flood defences. Awareness of these future hazards could also hasten the transition to reduce fossil fuel emissions.

The research created the worst-case scenarios using a blend of real-world events, computer simulations and climate physics. The possibilities exclude broader worldwide issues such as the agricultural collapse and increased conflict.

This work was initiated as part of a official risk assessment framework. Previous assessments have warned that not enough attention was being allocated to catastrophic yet improbable risks.

An independent advisory body has stated that the UK needs to "become resilient to moderate heating" and assess the threats for 4C. Earlier government strategies have been criticised as being "insufficient" by environmental groups.

A national response commented: "The climate emergency is at the center of our national priorities, both building resilience and becoming a clean energy superpower. It is crucial that the UK is resilient for the impacts."