Unprecedented heat wave disrupts United Kingdom air and rail traffic

The manager of most of the United Kingdom's railway network warned passengers to not travel over Monday and Tuesday unless "absolutely necessary" because of a potentially record-breaking heat wave underway in France and the U.K.

Why it matters: Heat waves can have a brutal effect on infrastructure — like railways and tarmacs — not designed to withstand abnormally high temperatures, which can disrupt transportation for thousands of people when they should not be outside for a prolonged period of time.

• As climate-change-induced heat waves and high temperatures intensify and become more common, cities may have to rebuild, redesign and adjust standards for infrastructure.

The big picture: Network Rail said Sunday that it would close all locations on the East Coast Main Line between London King’s Cross and York and Leeds during the afternoon rush hour through Tuesday in response to the scorching heat.

• It said the closures were required because the infrastructure likely can't withstand such extreme temperatures. Rail lines expand when they heat up, and they can warp and buckle if they are exposed to temperatures they weren't designed for.
• The Royal Air Force said Monday it halted flights at Brize Norton air base, its largest air station, because of high temperatures but that there "is no impact on RAF operations," as planes are using alternative airfields.
• Britain's Luton airport suspended flights on Monday after a runway defect was discovered during high temperatures across the country.
• Hot temperatures can cause aircraft tires to sink into the pavement. During periods of high heat, many planes also have performance restrictions due to a need for longer runway lengths. Brize Norton is home to much of the UK's fleet of transport and aerial refueling aircraft, which are large aircraft, and U.S. cargo and refueling planes also use the base.

What they're saying: "Closing the line to traffic is always a last resort but it is the right thing to do to keep people safe on Tuesday given the unprecedented heatwave forecast," Sam MacDougall, operations director for Network Rail, said.

• "The forecast temperatures are well above those which our infrastructure is designed, and safety must come first," MacDougall added.

London Mayor Sadiq Khan also warned the public to only use public transportation "if your journey is absolutely necessary."

• "Plan ahead, carry water and be prepared for delays, particularly on the London Underground which will be running with speed restrictions," Khan added.
• "Londoners who do not have to travel to their place of work should work where they feel most comfortable. For many, this will mean staying at home, while others may prefer to go to office spaces which may be cooler and air-conditioned."

The heat wave is a climate change-related public health emergency that could potentially kill several thousand people across western Europe, Axios' Andrew Freedman reports.

• It's already killed hundreds in Portugal and Spain and has contributed to massive wildfires in southern France, parts of Spain and Portugal, which have forced thousands to evacuate their homes.
• The U.K. Met Office is forecasting the country's first-ever occurrence of 104°F (40°C) temperatures during this event, with a high of 97°F Monday.

Go deeper: U.K. issues first-ever Red warning for extreme heat wave

Editor's note: This post was updated with additional details throughout.