Acid rain in HK
Kane
sources: Ming Pao
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When rain has a pH value of less than 5.6, it is called "acid rain". In the first quarter 1998, the rain in HK had a pH value of 4.0 only. The situation seems to be worsening. If the rain has a pH value of less than 4.0, it is as acid as vinegar.
How terrifying!! The pollutants that cause acid rain are SO2 and nitrogen oxides which mainly come from power plants. The amount of pollutants released by local power plants have decreased, however, the acid rain problem still exists because the pollutants which cause acid rain are blown to HK from S.China.
The HKSAR government has been working with the Guangdong government in finding out the source of air pollution in Pearl River Delta (PRD) for years, hoping to make agreement with Guangdong government in reducing air pollution in the region.
It is found that such pollutants were produced because the power plants in the PRD mainly use coal and oil to generate electricity. In addition, the number of cars in PRD is increasing rapidly. In winter, the prevailing wind is northerly, the wind blows the pollutants from PRD to HK. You see, it is a "intra-topics" matter in the sense of geography.
By the way, why are we concerned about acid rain? Acid rain can causes damages to crops, it will dissolves the nutrients in the soil quickly, thus prevents plants and crops from taking in the nutrients. Hence reduces agricultural productivity. It also affects our health both directly and indirectly. The acidic gaseous pollutants in the air weaken the functions of the lungs and the heart, making us easier to suffer from asthma and chronic bronchitis.
But, in 1999, Mr Gordon Siu, Secretary for Planning and Lands Bureau said that the pH value of acid rain in HK is not too low. Do you think so?
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