What is the weather forecast?

The war promoted the development of weather maps.

1820, brandes, a German, used the meteorological observation data published in the Journal of Baladin Meteorological Society to fill in the records of air pressure and wind on the map at 1783, and drew the first meteorological map in the world in Leipzig. The birth of weather map opened the prelude to the development of weather forecast. However, popularizing weather forecast is a war.

1853- 1856, Britain and France launched the Crimean war against Russia. 1854165438+1October 14 British and French troops surrounded Sevastopol. When the Marine Corps was about to land in Balaclava port, the storm fell from the sky, and the Black Sea suddenly became violent. The French warship Henry IV was buried in Fausto, and the British and French allied forces almost suffered a disaster.

In this war, Charles Louis Napolé on Bonaparte noticed the French astronomer Le freire. In his view, since Le freire can predict the position of the traveling star, he can also predict the position of the storm. He ordered Le freire to study the storm, so Le freire sent letters of help to observatories and meteorologists all over the world, and collected meteorological data from181412+0.00 to 16. He drew five daily weather charts. After research, he found that the storm moved from northwest to southeast,1October 1 12 to 13 were still in Spain and western France, and 14 moved eastward to the Black Sea. If the weather forecast is timely, this disaster can be avoided.

In the following days, countries such as Europe and America followed suit, organized observation networks to send weather telegrams, drew ground weather maps and predicted future weather changes.

Forecast the weather or rely on weather charts.

The war has passed 170 years, but the weather map is still full of vitality now with advanced technology. As far as the current weather forecast is concerned, there are generally four steps: the first step is to analyze the current weather conditions and understand the weather system that produces the current weather. As far as Hangzhou is concerned, to master different weather systems in different seasons, we should pay more attention to the weather systems in Malaysia and the Philippines in summer. Pay more attention to Mongolia in winter. The second is to analyze whether this weather system will affect Hangzhou; Third, the time and intensity of the impact; 4. Forecasters analyze the local weather conditions, and make further corrections according to their own experience and ability, combined with satellite cloud images, so as to make the forecast more accurate.

And mastering the current weather situation depends on the weather map. Weather maps are mainly divided into ground and high altitude, both of which are observed by human beings. The ground map is full of dozens of meteorological elements such as temperature, air pressure, wind direction, wind speed, cloudy, sunny, rain and snow. The high-altitude map is the wind direction and wind speed at different levels from the near ground to 20 thousand meters high in the air. According to the regulations, the ground map is updated every three hours, and the altitude map is updated twice a day.

Because the atmospheric system knows no national boundaries, the weather map of every country is enjoyed by * * *. In other words, every country and region in the world sends its own weather map to the International Meteorological Organization every day, and the International Meteorological Organization distributes it to all countries and regions as needed. So China can forecast the weather in American cities, and Europe and America can also forecast the weather in Hangzhou.

Prediction errors are also possible.

Although all countries in the world have set up "catching nets", the atmospheric circulation system is changing rapidly, and people can't fully understand it now, so the weather forecast will naturally be inaccurate. As far as the forecasting process is concerned, there may be several errors: the error of observed data at that time, the error in transmission process and the error of personal experience. At present, according to the relevant requirements, the forecast accuracy should reach more than 80%, which means there can be 20% error.

However, on the whole, due to the progress of technology, the weather forecast is more and more accurate now. Any computer, satellite, radar, lightning locator, etc. Can quickly and accurately capture the weather changes. It can be said that the typhoon has not been missed since there were satellites in the sky. In the past, typhoons came from the sea, so it was difficult to know.

Although the accuracy of prediction is improving, people's requirements are also improving. They want to be more detailed and accurate, and it is best to be accurate when it will rain, so they often complain that the weather forecast is not accurate.