What are ‘tropical nights'? The growing health threat facing Brits in tourist hotspots

Yahoo

15-04-2025

British holidaymakers preparing for a summer holiday abroad this year should be wary of extremely hot evenings as chances of so-called 'tropical nights' increase across Europe, experts have warned.
In a new report released on Tuesday, the EU's Copernicus Climate Change Service said that Europe is currently the world's fastest-warming continent with the most affected countries, including popular tourist destinations such as Italy, Spain, Turkey and Greece.
The report - the European State of the Climate 2024 - also revealed that last year saw a record-breaking rise in "tropical nights", when the minimum daily temperature does not drop below 20C.
Despite the exotic-sounding name, tropical nights can cause serious health problems, especially for children and the elderly, and have become increasingly common in south-eastern Europe.
The report revealed 23 tropical nights hit the region last summer as a lengthy, serious heatwave engulfed multiple countries.
And as Brits prepare for their summer holidays, it is important they are careful in extreme weather conditions - taking measures such as cold showers and avoiding alcohol, caffeine and hot drinks.
Prof Dann Mitchell, professor of climate science, University of Bristol, and Met Office joint chair in climate hazards, said night-time temperatures are "really important for our health" because it's at night when our bodies recover.
He said: 'Warm nights are associated with distinct physical and mental health burdens, and this is mainly related to our body not being able to recover, which is one of the primary functions of sleep.
'The increased heat stress put on our bodies during tropical nights leads to greater risk of heat-related illnesses, such as heatstroke and cardiovascular failure.'
Alongside its warning on tropical nights, the European State of the Climate 2024 found that the continent is warming twice as fast as the global average. It also said Europe experienced the longest heatwave on record in July in southeastern Europe, as well as major glacier mass loss across Scandinavia and Svalbard.
Storms were often severe and flooding widespread, with the report highlighting that Europe suffered 'serious impacts from extreme weather'.
The 2024 July heatwave lasted 13 consecutive days and affected 55 percent of the region, while there was a record-breaking 66 days with at least 'strong heat stress' - when daily temperatures reach a 'feels-like' temperature of 32°C or higher. The previous average was just 29 days.
Met Office spokesman Grahame Madge told Yahoo News: 'Tropical night thresholds are more frequently met in southern Europe and the Mediterranean, but even here the number of events each year is expected to rise.'
Increased heat can put the body under stress and high nighttime temperatures can also affect health, offering little respite from high daytime temperatures.
Warmer nights can disrupt sleep and cause an uptick in heat-related illnesses, hospital admissions or even death for vulnerable people.
The elderly are especially vulnerable as are pregnant women, whose bodies are less able to regulate their temperature, while children can also be susceptible to heat-related illnesses because they have smaller bodies so warm up faster.
Experts say the increased heat stress during tropical nights can lead to greater risk of heat-related illnesses, heatstroke and cardiovascular failure.
Additionally, the associated lack of sleep is also linked with our mental state, so issues such as anxiety and depression can be heightened.
Mitchell said: 'There is a known link between poor sleep patterns, and dementia such as Alzheimer's disease.
"A single tropical night will not impact this, but decades worth of them will, and we are expecting to see many more extremely hot nights in the future, due to the increased background temperatures caused by human induced climate change."
The number of tropical nights in the UK has increased significantly since the 1960s. According to the Met Office, there were 44 tropical nights in the 30 years between 1961 and 1990, whereas between 1991 to August 2020, 84 tropical nights were recorded - with 21 of them occurring since 2008.
During the July 2022 heatwave, the UK recorded its hottest night on record, when a low of 26.8°C was recorded at Shirburn Model Farm in Oxfordshire over a 24-hour period.
Madge said that tropical nights are "still rare" in the UK although they are becoming more frequent.
'This can be extremely uncomfortable for sleeping, preventing people from obtaining sufficient rest and respite during heatwave events," he said. "Some, especially those with underlying health conditions can struggle and some may need additional health support or treatment.
"With climate change raising UK temperatures we can expect more tropical nights to occur more frequently in line with more extreme heatwaves.'
There is a higher frequency in the south of the UK, and this is projected to increase in the coming years.
The rise in night-time temperatures can be fatal, too - during the summer of 2022, an extra 2,800 people aged over 65 are estimated to have died from heat-related reasons, according to government data.
The UK Health Security Agency (UKHSA) said that in England during the summer of 2024, 1,311 heat-related deaths were recorded.
While there is still a considerable variation in climate, scientists cannot predict the exact number of tropical nights or heat waves expected this year but believe they will increase.
Met Office principal fellow for climate extremes, Paul Davies, said: 'As our climate warms we know that we will see more frequent and more severe hot spells, and we're starting to see the increase in frequency already.
'Tropical nights can have a significant impact on people and infrastructure as there is no time to recover overnight. It is clear that we're already seeing the impact of climate change, and we're likely to see even more tropical nights, even in September, as our climate warms.'
Often experts cite climate change as contributing factor to increased temperatures with severe hot weather rising across the continent.