Storm Babet was the second named storm of the autumn season in 2023, and it brought widespread disruption and damage to the UK from 18 to 21 October. The storm was caused by two low-pressure systems that merged over the British Isles, bringing heavy rain and strong winds from an unusual south-easterly direction. In this blog post, we will explore why Storm Babet was so severe and whether the UK can expect more severe storms in the future.
The severity of Storm Babet
Storm Babet was severe for several reasons. First, it affected a large area of the UK, especially Scotland and northern and eastern England, where it dumped up to 250mm of rain in some places, more than double the average rainfall for October. This caused widespread flooding, especially in eastern Scotland, where a red "danger to life" warning was issued by the Met Office. Hundreds of homes were submerged, roads were closed, and power supplies were cut off. Seven people lost their lives due to the storm.
Second, Storm Babet brought strong and damaging winds that reached up to 70mph in some places. These winds were particularly impactful because they came from a south-easterly direction, which is less common for storms hitting the UK. The prevailing wind direction is usually south-westerly, so trees and structures are more adapted to withstand it. However, a south-easterly wind can expose more vulnerable parts of nature and infrastructure, causing more damage. This was also the case for Storm Arwen in 2021, which felled many trees and disrupted transport and communication networks.
Third, Storm Babet lasted for several days, prolonging the impacts of heavy rain and strong winds. The storm moved in from the south-west on Wednesday 18 October, and was joined by a second low-pressure system on Thursday 19 October. The storm then lingered over the UK until Saturday 21 October, bringing persistent rain and gusty winds to many parts of the country. The prolonged exposure to severe weather increased the risk of flooding, power cuts, and travel disruption.
The future of storms in the UK
Storm Babet was not an isolated event, but part of a trend of more frequent and intense storms affecting the UK in recent years. According to climate scientists, this trend is linked to global warming, which is causing changes in atmospheric circulation patterns and ocean currents that influence storm formation and behaviour.
One of these changes is the weakening of the jet stream, a fast-moving band of air that flows from west to east across the Atlantic Ocean and influences weather systems over Europe. The jet stream is driven by the temperature difference between the cold polar air and the warm tropical air. However, as the Arctic warms faster than other regions due to climate change, this temperature difference is reduced, making the jet stream slower and more wavy. This means that weather systems can get stuck or move more slowly over certain areas, leading to longer-lasting and more extreme events.
Another change is the warming of the sea surface temperatures in the North Atlantic Ocean, which provides more moisture and energy for storms to develop and intensify. Warmer seas also increase evaporation rates, which can lead to heavier rainfall and flooding. Moreover, warmer seas can alter ocean currents such as the Gulf Stream, which carries warm water from the tropics to the north-east Atlantic and moderates the climate of western Europe. If the Gulf Stream slows down or shifts due to climate change, it could affect the frequency and intensity of storms hitting the UK.
What can we conclude?
Storm Babet was a severe storm that brought heavy rain and strong winds to large parts of the UK in October 2023. The storm was caused by two low-pressure systems that merged over the British Isles, bringing unusual south-easterly winds that caused more damage than usual. The storm also lasted for several days, prolonging its impacts on communities and infrastructure.
Storm Babet was not a rare occurrence, but part of a trend of more frequent and intense storms affecting the UK in recent years. This trend is linked to global warming, which is causing changes in atmospheric circulation patterns and ocean currents that influence storm formation and behaviour. These changes include a weakening of the jet stream, a warming of the sea surface temperatures in the North Atlantic Ocean, and a possible alteration of the Gulf Stream.
As climate change continues to worsen, we can expect more severe storms like Storm Babet to hit the UK in the future. This poses significant challenges for disaster preparedness, response, and recovery. Therefore, it is crucial that we take urgent action to reduce greenhouse gas emissions and adapt to the changing climate.