When the summertime starts on Sunday, many are looking forward to the "longer" days. The additional daylight in the evening hours but must be cut off in the morning - it will be bright later.
However, summer time, which has existed in Germany since 1980, could soon be over. The EU Parliament voted on Tuesday to abolish the time change. It pleads for the clocks 2021 last change. There are many arguments for or against it, even for a permanent summer or winter time. Which ones are right?
1. Statement: The previous back and forth harms the health, because our internal clock each time confused.
Rating: Maybe right
The background: There is evidence that our internal clock does not adapt so easily, especially in the spring. The health insurance company DAK, for example, has found in a long-term observation that in the first three days after the time change, 25 percent more patients with heart problems came to the hospital than the annual average.
However, the health insurance researchers compared the number of hospital admissions on the first three working days after the time change (ie Monday, Tuesday and Wednesday) with the hospital admissions over the whole year. This weakens the results, because on Mondays anyway significantly more people suffer a heart attack than on other days of the week. However, studies from Sweden, Croatia and the USA support the hypothesis that after the time change in the spring the risk of infarction rises somewhat (read more here).
In a Forsa survey commissioned by the DAK (2018), around one in four said that they had had time-shifting problems before - most reported falling asleep and staying asleep. But the other way around, it also means that three in four respondents can not remember health issues from the time change.
2. Claim: A permanent summer time would hit students particularly hard.
Rating: Right
The background: When switching to permanent summer time, it gets light in the morning one hour later in the morning. However, people need the blue light of the sun's rays to wake up. It is the "main clock" for the inner clock and decisive for the wake-sleep rhythm.
For this reason, the German Society for Sleep Research and Sleep Medicine is in favor of maintaining the normal time - that is, against a permanent summer time. According to the Munich chronobiologist Till Roenneberg, a permanent summer time would actually affect teenagers particularly hard.
Puberty disrupts the inner clock and makes many teenagers long-sleeper. Already the start of school at eight o'clock in the morning is comparable to starting work at four o'clock in adults, says Roenneberg in a podcast of the Institute for Medical Psychology of the LMU. The time change sharpens this problem. Possible consequences include loss of concentration and performance.
The German Teachers Association also considers a permanent change to summer time irresponsible. According to Association Leader Heinz-Peter Meidinger, such a regulation would lead to "that more than ten million pupils in Germany would have to spend two months in total darkness in their morning schooling, which would not least increase the number of accidents".
3. Statement: A permanent winter season comes closest to the natural conditions.
Rating: Is true with restrictions
The background: Our daily routine would be most adapted to nature, when the sun would reach its zenith at 12 noon - that corresponds to the "solar time". For example, in the winter in Görlitz, on the easternmost tip of Germany. Even in Hamburg or Dortmund, the sun and time are no longer consistent because they are much further to the west. If we look at large parts of Europe, the matter becomes even more complicated.
The basis is the time zones. For them, the globe, starting from the Prime Meridian in Greenwich near London, is divided into 24 zones with a width of 15 degrees each - theoretically. From one of these zones to the next, the time difference is one hour each. The problem: In reality, political boundaries and geographical conditions distort the outlines of the time zones.
Thus, about the same time applies from the Spanish Atlantic coast to the Polish eastern border. As a result, the sun in Spain reaches its highest point only around 1 pm, in Poland around 11 am. The "natural" conditions corresponds to the permanent winter time so only in a small part of the continent, in the east, the summer time would even better match the state of the sun. In the West, on the other hand, this would aggravate the discrepancy compared to the permanent winter time.