Do you know which is the hottest?

It has been more than ten days for Lesser Heat, and he will enter Greater Heat in another week. And then stay up for another month and it will be hot everywhere. This is the hottest time of the year. During this period, there will also be the dog days that we are most concerned about. The length of the dog days varies from 30 days in some years to 40 days in some years.

I think everyone is most concerned about how many dog days there will be this year.

This year's dog days begin today, that is, July 17, 2018, and end on August 25 in the Gregorian calendar for 40 days. Did it heat up before the hottest day began? Yes, there will be 40 dog days this year, including 10 days at the beginning, 20 days at the middle and 10 days at the end.

I think at this time you should wonder why there are still dog days for 30 days?

I also take a special look at the length of dog days in recent years, and find that among the three dog days in recent eight years, there are only 30 dog days in 2014 and 2012.

In fact, this is mainly related to the traditional astronomical calendar of our country, that is, the problem of ten days dry and twelve earth branches. As the saying goes, "the Summer Solstice counts his head at the top of his head." The ancients used the combination of heaven and earth to calculate the days. In this way, there will be a Geng day every ten days, so the time for the beginning of the first volley is determined, and the Summer Solstice's fourth day is the beginning of a moderate volley, so the first volley can be determined as the next ten days. Then came the last volt. The first day after the Beginning of Autumn was the last volt, and the last ambush time was ten days. So the middle ambush time is uncertain. Sometimes it's 10 days, sometimes it's 20 days.

Which volt is the hottest in dog days?

As the saying goes, "the cold is in 39, the heat is in the middle", so it seems that the hottest should be in the middle. Why is it the hottest in the middle? First of all, let's take a look at the problem of heat budget. After entering Lesser Heat, the weather will get hotter and hotter. When it accumulates to the middle volt, the heat budget of the earth is already very unbalanced, because the heat during the day cannot be dissipated at night. So when you reach the peak of heat accumulation in the middle volt, it will naturally be so hot that you just want to hide in the air-conditioned room.

In addition, the period from mid-July to mid-August is usually between mid-July and mid-August. During this period, there is a lot of Rain Water, and the air is not well ventilated, giving people the impression that although it is raining heavily, it is more muggy.

During this period, most parts of China are ruled by the subtropical high, which is dominated by downdraft, the weather is clear, the direct light is strong, and the surface warming is faster.

However, the weather is hot on dog days, so we should do a good job in preventing heat. Also be careful not to eat too much cold food and not to take a cold bath after sweating, which is very bad for your health.

The above comes from promoting agriculture through science.