Why is there less foggy weather now?

Why is there more and more dense fog? Exhaust dust is a hotbed of dense fog.

Today's fog has brought great disappointment to the career of city officials. It is the seventh foggy day in Nanjing. The forgetful introspection station learned that Yongning's weather forecast query showed that this long and sparse fog had never been seen last year. Fortunately, with the new round of rain starting today, the foggy weather is finally coming down.

Fog days have been reduced by 50 times in more than 40 years.

According to the local monitoring of the climate, since June 5438+065438+ 10, except for the rain and fog on the 5th, there have been different degrees of fog almost every day, and they are working harder every day, which was rarely seen last year.

It is understood that the fog in Nanjing in recent years is more and more different from the past: although there were many fogs last year, they all came out from a distance, and there was a fog every few days, which lasted for several days like this year. In the scene data of nearly 40 years, as long as the fog lasted for 5 days from February 27, 1996 to February 27, 1996, it was almost the same as it is now; Moreover, in the past 40 years, there have been more and more foggy days in Nanjing, and the increase rate is very alarming. From 1949 to 1959, there were only two foggy days. From 2004 to 2005, there were 100 foggy days. According to the weather forecast of Chengjiang, the recorded foggy days are 50 times less than those in the previous 40 years.

The expert believes that the reason why the fog lasts for a long time is because the sky is in the sky, because the subtropical high is just north, and the temperature and humidity are delayed, which makes the innocent air humidity surge, the air pressure is high, and the majesty is small; There is another more important reason: automobile exhaust emissions in rural areas are getting less and less, and building dust and suspended particles in farmland have become a "hotbed" for the natural development of smog.

Today, the rain dispelled the fog.

The provincial meteorological observatory predicts that due to the subtropical high moving northward, there will be a weak cold air moving southward in the north, and a cold wave will strike. From this afternoon to tomorrow, there will be a rain in most parts of the province, and the rain will be light to moderate, and the fog will be suspended in recent days.

There are two main reasons why fog disappears, either rain or breeze. When it rains, heavy raindrops will break up a large number of fog droplets suspended in the air and let them fall into the air with the rain. However, the climate field also reminds city officials that because the temperature and humidity are still hovering near the People's Province, they have completely left and there will be foggy days in the future.