Why is the accuracy of long-term weather forecast not high?

Internationally, the weather forecast within 10 days has certain accuracy, but the forecast over two weeks, that is, the long-term weather forecast, has great uncertainty. This is because chaos is a common phenomenon in weather systems, and it shows an inherent randomness in deterministic systems.

Its external performance is very similar to pure random motion, that is, unpredictable. Chaotic systems are very sensitive to small initial value changes or disturbances. No matter how small the disturbance is, it will completely deviate from the original evolution direction after a long time.

Weather forecast:

1. The weather often changes. Weather forecast is to use meteorological data and apply the principles and methods of meteorology to predict the weather in a certain period in the future according to the weather situation.

2. Weather forecast has existed since ancient times. Through long-term observation and experience accumulation, the ancient working people summed up many proverbs about the weather. The typical weather forecast is "stay indoors at sunrise and travel thousands of miles at sunset". However, proverbs are all based on experience, so they are still limited and even some are wrong.

The current weather forecast is released by the Meteorological Observatory and made public. At present, the main ways to publish weather forecast are TV, Internet, newspapers, SMS, WeChat and so on.

An important tool of weather forecast is weather map. The weather map has the motion law of the weather system, and meteorologists predict the future weather conditions according to it. In addition, meteorologists should also study satellite cloud images and revise the prediction results in combination with local characteristics and experience.