How to treat the weather temperature above zero and below zero?

Weather temperature can be viewed from two aspects: weather forecast and thermometer, as follows:

1. Weather forecast: In weather forecast, the expressions above zero and below zero are judged by temperature signs. It is bounded by 0 degrees Celsius. Add a "-"sign to the symbol before the number to indicate zero. There is nothing in front of the number, which means zero. For example, -5 degrees Celsius means minus 5 degrees Celsius, and 5 degrees Celsius means minus 5 degrees Celsius.

2. Thermometer: Generally speaking, the number on the thermometer decreases from top to bottom, and 0℃ is the dividing line between the temperature above zero and the temperature below zero. Above 0℃ is the temperature above zero, and below 0℃ is the temperature below zero.