Related classifications of weather systems
The characteristic scales of various weather systems in the atmosphere vary greatly, ranging from those as large as tens of thousands of kilometers, such as ultra-long waves and subtropical highs, to those as small as a few hundred meters, such as tornadoes. According to the characteristic scale, it can be roughly divided into five categories, namely: planetary scale weather system, synoptic scale weather system, mesoscale weather system, mesoscale weather system and small scale weather system. The classification of weather systems is not completely unified internationally.
1. Mesoscale weather systems
In American classification terms, systems with horizontal scales from 2000 kilometers to 2 kilometers are collectively called mesoscale weather systems, which are divided into three categories :
The mesoscale α weather system is called 200 to 2000 kilometers, including typhoons, fronts, etc.; the mesoscale beta weather system is called 20 to 200 kilometers, including tornadoes, squall lines, etc.; 2 to 20 kilometers It is called mesoscale gamma weather system, including thunderstorm cells, etc.
2. Mesoscale weather systems
In Japan, systems within the range of 2,000 kilometers to 200 kilometers are called mesoscale weather systems, and systems within the range of 200 kilometers to 1 kilometer are called mesoscale weather systems. system, called a mesoscale weather system.
3. Large-scale weather systems
In addition, planetary-scale weather systems and synoptic-scale weather systems are also collectively referred to as large-scale weather systems.
4. Sub-synoptic scale weather systems
All weather systems smaller than the synoptic scale, including mesoscale, mesoscale and small-scale weather systems, are collectively referred to as sub-synoptic scale weather systems. ; Some people only refer to systems that are smaller than synoptic scale systems (that is, specifically referring to mesoscale weather systems) as subsynoptic scale weather systems.
A more objective and unified classification of weather systems requires further research.
5. Division by wave number
On high-altitude weather maps, weather systems are also divided according to the wave number of the entire latitude circle. Fluctuations with wave numbers of 1 to 3 are usually called super Long waves. Fluctuations with wave numbers between 4 and 8 are called long waves. They all belong to planetary scale weather systems. Fluctuations with wave numbers greater than 8 are called short waves, which are equivalent to synoptic scale weather systems or smaller scale weather systems.