Reacción a "Not changing the time in summer or winter in the US would reduce strokes and obesity, according to a study"

For me, a common denominator in many of these studies advocating the elimination of seasonal time changes in countries outside the tropics is that they seem to lack an understanding of the fundamentals of seasonal time changes.

Let me explain: in tropical areas, the sun rises and sets at times that vary little throughout the year. These countries do not have winter and summer time; they do not change their clocks simply because they do not have seasons.

But outside these areas, this is not the case; we have seasons. For example, at the latitude of Spain (which coincides with that of the northern United States), the sun rises three hours later in December than in June, and sets three hours earlier in December than in June. In other words, the day is six hours (or more) longer in June than in December.

Therefore, it is not possible to stick to a fixed time as in tropical countries. If, for example, in Spain or much of the US, you lock the official time in winter, in the middle months of the year it will dawn very early, and the average person's activation will be out of sync and will take place when the sun is already very high on the horizon. The opposite occurs if you lock the official time to summer time.

And finally, two more objections:

• On the quantitative side: the authors are theorising variations that, in many cases, would be less than 1%! (In many of these studies, the claimed quantitative benefit data is less than the data's margin of error). Some time ago, José María Martín Olalla and I published this paper in which we quantitatively defined the margins within which some of the items studied in that paper could move, which are lower than one might think.
• The authors talk about eliminating the seasonal time change to obtain minimal variations, without taking into account what the social reaction and consequences of such a measure would be (for example, that many people could be forced to change their schedules to adapt to the fact that they live in an area with seasons). To give a very exaggerated example: it is as if someone told you that the solution to ending tooth decay is to pull out the teeth of the entire population.