What Is a Synoptic Chart?

A weather map is a special map filled with meteorological elements at the same time. The base map of the weather map is filled with the locations of cities, stations and major geographical indications such as rivers, lakes and mountains.

In 1820, HW Brandes of Germany filled in maps of the same time observations of pressure and wind in the past and plotted

Weather maps can be simply divided into two categories, "ground" and "altitude." "Ground" actually refers to the surface of the earth, which can represent very different heights at different locations, such as the ocean or ridges. Therefore, when reading the map of ground weather, temperature, wind direction and wind speed, pay attention to the altitude represented. On the other hand, in order to facilitate the comparison of different air pressure systems, the air pressure map uniformly uses the average sea level as the reference altitude. ^[4]

The birth of weather forecast was related to a war.

In November 1854, the famous Crimean war in history was fierce. British and French forces surrounded Sevastopol, and the Marines were preparing to land in the Balaklava port of the Black Sea. At this time, the Black Sea was suddenly windy, and the waves were sky-high. The British-French coalition collapsed without a fight, and almost all the army collapsed.

At the request of the military, Lefrier, director of the Paris Observatory, studied the storm. He sent letters to meteorologists around the world to collect weather reports before and after the storm. After collecting the meteorological reports, he filled in a meteorological situation on the map at the same time. By analyzing the maps at different times, he found that the storm moved from west to east. It had affected Spain and France 1 to 2 days before reaching the Black Sea.

Lefrieux analyzed that if there were weather stations in Europe at that time, the storm situation would be able to telegraph the British and French fleets in time to prevent the British and French fleets from the storm. In March 1855, he suggested to the French Academy of Sciences that an observation network be organized to quickly collect observation data in one place, analyze and draw weather maps, and it is possible to infer the path of future storms. In 1856, France established the world's first formal weather forecast service.