🔗 Share this article

The most severe potential impacts of the climate crisis for the UK have been detailed by scientists, encompassing a scorching 4C increase in mean temperatures to a 6.5-foot surge in sea level. A separate possibility foresees a decline of 6C in temperature following the collapse of critical Atlantic Ocean currents, which would massively disrupt farming and power requirements.

Plausible Outcomes, Not Guarantees

These effects, a number of which are linked to irreversible climate shifts, are considered as low probability but possible. The scientists said that these models filled a gap in risk assessment that had rendered the UK ill-prepared for extreme outcomes.

"The climate extremes we have outlined should not be seen as certainties, but they are credible," commented Nigel Arnell who directed the study. "Britain has been planning in the absence of the tools to plan for worst-case scenarios. We've now supplied decision-makers what they need to prepare for future conditions they hope never happen, but dare not dismiss."

A Range of Harsh Climate Projections

Another collection of worst-case scenarios details the potential extent of extreme weather between now and the end of the century. These show that temperatures could rocket in particular seasons by up to 6C above historical levels, while rainfall could be 300% of standard measurements.

The chance of the catastrophic events occurring remains uncertain due to unknown factors about what action will be taken to tackle climate change and how the Earth's systems will react. This approach was compared to defence planning or scenario planning for financial systems.

Critical Scenario Highlights

• 4C Temperature Rise: Worldwide averages rising well above 4C by 2100 could transpire if climate action fails or if strong feedback loops like the tropical forests becoming a net carbon source unleash its vast reserves of carbon. This would result in extreme and prolonged heat domes and droughts hitting the UK in summer.
• Atlantic Current Collapse: A critical sea current, the North Atlantic current, is weakening and losing stability due to ocean warming. A collapse commencing by 2030 would lead to a drastic cooling in the UK. "Crop production would be severely challenged and water resources would be drastically changed," said Arnell.
• Accelerated Coastal Flooding: A rise of 2.0-2.2 metres around the UK by 2100 could occur if ice sheets in Greenland and Antarctica melt abruptly, inundating seaside communities. Differing from the other scenarios, this risk is already understood by coastal engineers.
• Aerosol Effect: Temperatures could also be increased by about 0.75C if pollution from industry is drastically reduced. This unexpected result occurs because pollution particles from industrial activity reflect solar radiation from warming the ground.

Building Resilience Against the Unthinkable

These dire projections could be used to inform the building of major projects, for example expanded cities, power generation facilities and urban drainage systems. Understanding these environmental threats could also hasten the push to slash carbon pollution.

The analysis formulated the extreme models using a mix of past data and records, digital projections and established principles. The scenarios exclude international cascading effects including the agricultural collapse and resource wars.

The project was requested as part of a national risk assessment framework. Earlier reports have warned that too little consideration was being allocated to catastrophic yet improbable risks.

An independent advisory body has recommended that the UK needs to "become resilient to moderate heating" and evaluate the risks for severe warming. Earlier government strategies have been criticised as being "inadequate" by environmental groups.

An official statement commented: "The climate emergency is at the core of our national priorities, both building resilience and becoming a renewable energy leader. It is crucial that the UK is ready for the effects."