Core Viewpoint - The air quality in the Sichuan Basin is expected to be generally good in the latter half of February, with some fluctuations due to fireworks and cold air activities [1] Summary by Relevant Sections Air Quality Forecast - The Sichuan Provincial Ecological Environment Monitoring Station predicts that the air quality will primarily be good to lightly polluted in early to mid-February, with deterioration expected due to fireworks during the festival [1] - From February 19 to 20, the impact of fireworks will weaken, leading to a slight improvement in air quality, although conditions will remain generally average [1] - Strong cold air is anticipated from February 21 to 22, which is expected to improve air quality to excellent levels [1] Specific Dates and Conditions - During the Spring Festival (February 16-18), the overall air quality will be good, but there is a risk of moderate to severe pollution in some cities due to fireworks [1] - From February 23 to 24, stagnant conditions may lead to a slow accumulation of pollutants, posing a risk of light pollution in certain areas [1] Uncertainties and Future Monitoring - There is significant uncertainty regarding future cold air activities and precipitation, which may require ongoing monitoring [1] - If biomass burning and fireworks are factored in, air quality could potentially improve by 1-2 levels compared to current predictions [1]

Group 1 - The core viewpoint indicates that the air quality in the Sichuan Basin is expected to improve gradually after a period of light to moderate pollution risk due to weak cold air activity and cloudy weather in early February [1][2][3] Group 2 - From February 2 to 4, there is a risk of light pollution in some cities, with individual cities facing moderate pollution risk on February 5 to 6 [2] - The northeastern region of Sichuan is expected to experience similar pollution risks, with a predominant good air quality forecast from February 7 to 14 [2] - The southern region of Sichuan also shows light pollution risks from February 2 to 6, with a return to good air quality expected from February 8 to 15 [2] Group 3 - The weather from February 2 to 5 will be mainly cloudy with increased humidity, leading to poor dispersion conditions and heightened pollution risk [3] - Cold air is expected to improve air quality from February 6 to 7, although western and southern cities may still face significant pollution risks [3] - Between February 8 and 12, intermittent cold air will help maintain good air quality, but from February 13 to 15, reduced wind speeds may lead to increased pollution risks again [3]