Although no one could see the wind, but people can feel it blowing the material to its existence and size and direction. Wind size, usually movement of air in unit time the distance that the wind speed as a measure of the size standards. With m / s, km / hour as a unit, said.

1. Wind

Commonly referred to as wind speed, is the average wind speed over time, such as say the average wind speed, monthly mean wind speed, average wind speed. This is because the wind from time to time, sometimes big, sometimes small, varied, so people in a period of time is the arithmetic mean for the average wind speed.

Determination of wind speed observations is the size. In the very early time, no determination of wind instruments, it is only by virtue of the dynamic surface properties to estimate the wind. According to records, the Tang had the wind is divided into eight grades, that is, blade, Ming article, shaking branches, fallen leaves, twigs break, break large branches off trees, flying gravel, off trees, and root.

2. Wind level

Now use the Bo Fu’s wind scale, is based on the dynamic surface properties, the wind is divided into 12 levels, with a total static wind 13. It was the basis of these 13 signs of the wind surface features, the feature at all levels made up songs as follows.

Wind and Smoke-free straight to the ground, a look at the wind smoke identified.

Two micro-ring breeze leaves, three branches waving Thinkpad T500 battery of red flags Yang.

4 paper dust dance, five water from the waves.

6 strong wind held the umbrella difficult, seven sticks of rock walking difficult.

8 gale micro branch off, nine wind crack house.

10 wind can pull the tree, 11-second land-based thin.

Meteorological stations are currently carried out through the wind instrument observations. There are two commonly used instruments. Something called pressure plate. It is a vertical suspension and freely swinging iron, connecting the top of the vane. Thus, iron status is always in the wind. In the wind when the iron up by the wind to float, to float according to the degree, you can know that the wind speed. Another called telex wind anemometer. It can be divided into two parts: the sensing part of the installation in the outdoor, direct part installed in the interior, between the two cables connected. Observation time, as long as a button, you can observe the indicator on the prevailing wind direction and wind speed.

When the current weather forecast weather is wind, that is, the level of release with the wind. Wind is simple. Average wind, the dry season, generally more than 6 wind, as wind; the flood season, five more than the wind, as wind.

“Bao Fu Feng-class”, from 0-12, consists of 13 wind level, which is thin Futi 1805 British out, and then added the corresponding wind speed for each class of data, so that the wind level The judge initially only by the natural landscape by the changes and the progress to have accurate wind speed data. This classification standard was gradually being recognized internationally. In 1946, the wind increased to 18 division-level grades, but in fact it was common to 12 the wind was the largest, more than 13 little wind there.

3. Wind

Where the wind come from? Southwest winds blowing from the northeast is called the north-easterly winds; wind blowing from the east west, called Dongfeng. Wind direction refers to the direction of the wind.

As early as 3000 years ago, my attention was the Yin to the wind observations, when the easterly wind called the valley, known as the Yi westerly wind, southerly wind known as Kay, known as the cool north wind. To the early feudal society, and further extended to eight wind Asus A6000 battery direction & position, hence “Bamianlaifeng” and eight said the Wind. The Tang Dynasty, the wind direction observation extended to 24.

The observed wind instruments, early Western Han dynasty, 2nd century BC, there waiting on the flags, use it with today’s airport, similar to the bag. To the Eastern Han dynasty, was made a “Wind of copper with Ukraine”, used to wind up.

Now, the meteorological station to the wind direction is divided into 16 to be observed. 16 of them in this direction, mainly east, west, south and north positive. The other two positive in each direction between the three again, that is between due east and due north into Northeast, North Northeast, East Northeast; due east and due south into the East between

South, East South East, South South East; due west and due north into between the Northwest and North by Northwest, cc North; due west and due south into between the southwest, west, southwest.

Observed wind instruments, is currently the most used benchmark, it can turn the shaft to rotate, the head always points to the wind comes. In order to facilitate observation, the wind vane with instructions under the direction of the cross, the crucifixion of “N ‘(refer to the direction of North), the word must be the local map is consistent with the North.

In the absence of wind vane place measures can be taken to observe the earth, is erected a bamboo or wood, the top line a rectangular piece of cloth, the wind, the banners fluttering PCGA-BP2V battery on the wind. Cloth swing direction is the wind went. Know the whereabouts of, you know the wind direction.

The wind not only the size, speed changing, and the wind often changes, it has its repeatability. People have all kinds of wind direction frequency of the wind there called “wind direction frequency.” More precisely, in a certain period of time, the same direction of the wind appears a few percentage of the total number of hours that the wind direction frequency. It is divided into say frequency, monthly frequency and annual frequency, is to describe an important indicator of wind energy resources, development of basic data for wind energy development plan.