400,000 heat deaths vs an Arctic freeze: Something bizarre is happening with London's winter weather this year

An intense El Niño can exacerbate extreme heat in some parts of the world, with experts estimating that the situation can result in more than 400,000 excess deaths due to the harsh conditions. Meanwhile, meteorologists are analysing atmospheric patterns which can affect the weather in Europe during winter, leaving a question mark hanging over the future weather of London. These new climate developments have brought two vastly different weather threats into the spotlight: excessive heat in some parts of the world and extremely cold weather in others.

The impacts of El Niño vary by region, and although an intense El Niño can affect temperatures, rainfall and atmospheric patterns over extensive regions, the extent of such disruption would depend on how the phenomenon develops along with other climatic and weather patterns.

One field of interest for London is the polar vortex. This phenomenon is a powerful air current circulating the Arctic Circle. If it is weakened or destabilised in any way, there is a chance of a change in atmospheric circulation patterns that will lead to an increased probability of freezing weather in certain regions of the UK.


This does not necessarily mean that the city will face an Arctic winter anyway. The connection between El Niño, the polar vortex, and winter weather in London is complicated.

Why Super El Niño is raising concerns about extreme heat

El Niño is a naturally occurring weather condition where the waters around the central and eastern parts of the equatorial Pacific Ocean become unusually warm.

In some cases where this phenomenon is very intense, its effects can be experienced all over different continents but in a way that varies from one place to another. This could either be in the form of prolonged heat and drought or increased levels of rainfall and floods.

The worries about heat deaths are as a result of the risks that extremely hot weather can pose to people. Heat waves bring about the risk of heat strokes, heat exhaustion, and dehydration. There are certain categories of people who are highly affected by heat, such as older people and individuals with preexisting health problems.

The estimate of more than 400,000 heat-related excess deaths has to be evaluated in its proper context. The significance of this figure depends on the scientific research behind it, the time period and whether it is an estimate, projection or a scenario which takes into account multiple climate-related elements.

It cannot be considered to mean the number of confirmed deaths that will happen in connection with the next El Niño.

The bigger worry is that, in addition to the global warming that occurs due to carbon dioxide emissions, El Niño may cause temperature increases that can be highly dangerous for public health.

How a disrupted polar vortex could influence London's winter

Although extreme heat is one of the main problems that some countries around the globe face, there are other issues that scientists pay attention to, such as the polar vortex and its possible impact on the winter weather in Europe.

This is the circulation of cold air in the stratosphere that is situated above the Arctic. It is most powerful in the winter of the Northern Hemisphere, but it changes from time to time.

However, when the circulation becomes weaker, sudden stratospheric warming takes place. The temperatures in the stratosphere increase abruptly, causing the disruption or even destruction of the polar vortex.

This may affect the processes of atmospheric circulation and the jet stream.

In certain circumstances, the emerging pattern will favour the existence of stable high-pressure systems. Should a blockage form that makes it possible for cold continental or Arctic air to be blown toward the UK, then there may be cooling and winterlike weather.

It might mean frost, icy weather, and even snow, should the temperatures and precipitation coincide.

But the exact result greatly depends on the positions of high and low-pressure systems and the direction of blowing air masses.

A dislodged polar vortex doesn't always cause freezing air to blow toward Britain. Some occurrences have little impact on the ground-level weather, while others have an effect on the weather patterns in Europe for several weeks.

Will London face an Arctic freeze this winter?

The potential occurrence of the cold period raises doubts about the probability of a harsh winter in London. Nevertheless, identifying the danger of a polar vortex disturbance is not equivalent of forecasting the weather the city is likely to get.

Indeed, El Niño can impact the circulation of the Northern Hemisphere, and there is no doubt that it can impact the polar vortex as well. Yet, such connections are not simple; therefore, a strong El Niño period does not mean that there will be a sudden stratospheric warming or exceptionally cold weather in the United Kingdom.

In addition to that, the North Atlantic Oscillation and the jet stream should be considered along with the formation of high-pressure zones.

However, from the perspective of London residents, what matters most is whether all these weather patterns lead to prolonged cold weather or just cause a temporary drop in temperatures.

A sound prediction will come from evolving observations and changing predictions as winter draws near. Seasonal predictions can suggest that some weather conditions are more probable than others but will not give an accurate forecast about when and where particular cold snaps will occur months ahead.

The possibility of hundreds of thousands of heat deaths and the likelihood of a cold winter in London are both parts of a complex system of the world's climate. This does not mean that one event is the direct cause of another.

In the meantime, the important thing is to look at how El Niño, the status of the polar vortex and the rest of the atmospheric conditions develop over the coming months. This will probably become clearer, but at the moment there is no basis for saying that London will experience a winter freeze.