Worryingly, scientists say that in the coming decades we could lose up to 60 hours of sleep each year due to tropical nights.

In Cluj-Napoca, it is no surprise that after nightfall, people did not go to bed but instead sought the coolness of the parks.

Man: "I don't have air conditioning. When you walk and relax, you sleep better".

Man: "A bit of exercise, cool air, and you sleep differently".

Woman: "It's not as hot as during the day".

When it is too hot at night, we fall asleep harder, wake up more often, and have a shorter period of deep sleep. A study that analyzed data from the sleep-monitoring bracelets of 47,000 adults from 68 countries and compared them with weather data from those areas showed that at an outside temperature of 25 degrees Celsius, we sleep about eight minutes less than at 10 degrees.

When thermometers show over 30 degrees, the sleep duration is approximately 14 minutes shorter. Thus, the study's authors indicate that, on average, a person loses 44 hours of sleep per year due to high temperatures. This will accumulate to 60 hours by the end of the century.

In Romania, nights are becoming increasingly warmer. An estimate from the Copernicus Climate Change Service shows that in the year 2000, we had on average one tropical night per year, meaning the temperature did not drop below 20 degrees Celsius during the night. This year we will have at least nine such nights.

Olivia Verișezan-Roșu, neurologist: "Especially those who do not have the means to cool their room come to us with sleep problems, possibly headaches if they cannot rest properly, concentration problems. The most affected will be infants and young children, the elderly, but also people with medical conditions".

Under these conditions, doctors recommend using fans or turning on air conditioners before going to bed, staying hydrated, and using bed linens and sleepwear made from natural materials.