The story takes place thousands of years later, in the year 3093, Earth time. In the future, the earth's resources have been exhausted, and mankind has entered an advanced civilization.
At this time, the average temperature of the earth is as high as 45 degrees, and the minimum temperature is about 20 degrees. Even the north and south poles have no glaciers.
The land area has been reduced by about half, and the global population is less than 500 million. Humans cannot go out and walk normally during the day. They must wear protective clothing made of special materials before going out.
Purpose: Protect human civilization