The picture on the left shows the day-night temperature change in the same place under different weather conditions, and the picture on the right shows the atmospheric heating process. Look at the picture and answer the questions. From figs. a and b

Analysis of test questions: As can be seen from the picture on the left, curve A does not change much day and night, indicating that it is cloudy at night, curve B changes greatly day and night, indicating that it is clear at night, and curve A indicates that the temperature difference between day and night is small, mainly due to the large amount of clouds, which is influenced by ① (the atmosphere has a strong weakening effect on the sun) during the day; ③ at night (strong atmospheric inverse radiation); The large temperature difference between day and night indicated by curve B is mainly due to the lack of clouds, which is influenced by ① (weak atmosphere weakens the sun) during the day; At night ③ (weak atmospheric inverse radiation).

Comments: The key to solve this problem is to look at the picture, which can not only reflect the weather conditions from the temperature difference between day and night of curves A and B, but also judge the thermal process of the atmosphere by combining the heating process of the ground and the atmosphere on the right. Need students' care and patience.