🔗 Share this article

The direst projected effects of the global heating for the UK have been outlined by researchers, including a blistering 4C increase in average temperatures to a 6.5-foot increase in sea levels. An alternative projection envisions a drop of 6C in temperatures following the shutdown of crucial Atlantic Ocean currents, which would profoundly upset farming and energy demand.

Possible Events, Not Guarantees

These impacts, some of which are linked to irreversible climate shifts, are seen as improbable but credible. The team explained that these projections filled a gap in forecasting that had left the UK not ready for worst-case results.

"The worst-case scenarios we have outlined are not forecasts, but they are plausible," stated Nigel Arnell who directed the research. "The UK has been planning lacking the frameworks to test against catastrophic outcomes. We've now provided policymakers what they need to get ready for climate outcomes they pray never occur, but dare not dismiss."

A Spectrum of Severe Conditions Possibilities

A further series of severe models sets out the possible scale of severe conditions between now and the end of the century. These indicate that thermometer readings could skyrocket in certain periods by up to 6C higher than historical levels, while rainfall could be three times standard measurements.

The likelihood of the catastrophic events happening remains uncertain due to unknown factors about what action will be enacted to combat climate change and how the climate system will respond. This approach was described as similar to security threat evaluations or scenario planning for economic stability.

Critical Outcome Elements

• Severe Heating: Global temperatures rising well above 4C by 2100 could transpire if climate action fails or if powerful amplifying effects like the Amazon rainforest becoming a net carbon source emit its huge repository of carbon. This would cause intense and enduring heatwaves and water shortages affecting the UK in summer.
• Ocean Circulation Failure: A major ocean current, the Atlantic meridional overturning circulation (Amoc), is weakening and showing signs of collapse due to ocean warming. A collapse commencing by 2030 would lead to a six-degree temperature drop in the UK. "Farming would be severely challenged and freshwater availability would be completely altered," noted the lead researcher.
• Accelerated Coastal Flooding: A surge of 2.0-2.2 metres around the UK by 2100 could occur if glaciers in the polar regions disintegrate quickly, flooding low-lying areas. Differing from the other scenarios, this risk is already recognized by infrastructure experts.
• Aerosol Effect: Global averages could also be increased by about 0.75C if industrial aerosols is rapidly cleaned up. This counterintuitive effect occurs because aerosol particles from burning coal reflect sunlight from reaching the ground.

Planning for the Unthinkable

The severe models could be applied to guide the development of major projects, such as expanded cities, power generation facilities and urban drainage systems. Awareness of these climate risks could also accelerate the transition to slash fossil fuel emissions.

The research formulated the extreme models using a blend of past data and records, digital projections and climate physics. These outcomes do not take into account broader worldwide issues like the agricultural collapse and increased conflict.

The project was requested as part of a national adaptation planning initiative. Previous assessments have warned that insufficient focus was being allocated to catastrophic yet improbable risks.

The government's climate advisors has recommended that the UK needs to "prepare for two degrees of warming" and examine the dangers for 4C. Past policy documents have been criticised as being "inadequate" by certain experts.

A government spokesperson noted: "Global warming is at the core of the country's focus, both building resilience and establishing itself as a renewable energy leader. It is vital that the UK is ready for the consequences."