Sulfur dioxide and nitrogen oxides dissolve very easily in water and can be carried very far by the wind. As a result, the two compounds can travel long distances where they become part of the rain, sleet, snow, and fog that we experience on certain days.
Human activities are the main cause of acid rain. Over the past few decades, humans have released so many different chemicals into the air that they have changed the mix of gases in the atmosphere.
Power plants release the majority of sulfur dioxide and much of the nitrogen oxides when they burn fossil fuels , such as coal, to produce electricity.
You are in Environment Causes and consequences of acid rain. Share in Twitter. Share in Facebook. Whatsapp Whatsapp. Acid rain, a true danger to living beings Acid rain is one of the consequences of air pollution. Contaminants come into contact with gases in the atmosphere and water vapour. They are transformed into a sulphurous acid, sulphuric acid and nitric acid.
This is known as acidification of the environment, a phenomenon that has serious effects: Oceans can lose biodiversity and productivity. The lowering of the pH of marine waters harms phytoplankton, a food source for different organisms and animals, which can modify the food chain and lead to the extinction of different marine species.
This acidification increases the concentration of metal ions — mainly aluminium ions — which could lead to the death of many fish, amphibians and aquatic plants in acidified lakes. In addition, heavy metals are transported to underground waters, which become unsuitable for consumption. In forests, the low pH level of the soil and the concentration of metals such as aluminium prevent vegetation from properly absorbing the water and nutrients it needs. This damages roots, slows growth and makes plants weaker and more vulnerable to diseases and pests.
Acid rain also affects artistic, historical and cultural heritage. In addition to corroding metallic elements of buildings and infrastructures, it deteriorates the external appearance of monuments.
The greatest damage occurs to calcareous constructions, such as marble, which gradually dissolve due to the effect of acids and water. For this, there needs to be a commitment at government and corporate level to drive a series of measures: Filter and detoxify the water used by the factories before returning it to the rivers.
Emergency Management. Survey Manual. Depending on where you live, maybe you've heard of acid rain. Now, acid rain is not pure acid falling from the sky, but rather it is rainfall or atmospheric moisture that has been mixed with elements and gases that have caused the moisture to become more acidic than normal.
Pure water has a pH of 7, and, generally, rainfall is somewhat on the acidic side a bit less than 6. But, acid rain can have a pH of about 5. Dead or dying trees are a common sight in areas effected by acid rain like these woods in the Jezera Mountains in the Czech Republic.
Acid rain leaches aluminum from the soil. That aluminum may be harmful to plants as well as animals. Acid rain also removes minerals and nutrients from the soil that trees need to grow. Acidic precipitation can be caused by natural volcanoes and man-made activities, such as from cars and in the generation of electricity.
The precursors, or chemical forerunners, of acid rain formation result from both natural sources, such as volcanoes and decaying vegetation, and man-made sources, primarily emissions of sulfur dioxide SO 2 and nitrogen oxides NO x resulting from fossil fuel combustion.
The burning of fossil fuels coal and oil by power-production companies and industries releases sulfur into the air that combines with oxygen to form sulfur dioxide SO 2. Exhausts from cars cause the formation of nitrogen oxides in the air.
From these gases, airborne sulfuric acid H 2 SO 4 and nitric acid HNO 3 can be formed and be dissolved in the water vapor in the air. Although acid-rain gases may originate in urban areas, they are often carried for hundreds of miles in the atmosphere by winds into rural areas. That is why forests and lakes in the countryside can be harmed by acid rain that originates in cities.
The environment can generally adapt to a certain amount of acid rain. Often soil is slightly basic due to naturally occurring limestone, which has a pH of greater than 7.
Because bases counteract acids, these soils tend to balance out some of the acid rain's acidity. But in areas, such as some of the Rocky Mountains and parts of the northwestern and southeastern United States, where limestone does not naturally occur in the soil, acid rain can harm the environment. Some fish and animals, such as frogs, have a hard time adapting to and reproducing in an acidic environment.
Many plants, such as evergreen trees, are damaged by acid rain and acid fog. I've seen some of the acid-rain damage to the evergreen forests in the Black Forest of Germany. Much of the Black Forest was indeed black because so much of the green pine needles had been destroyed, leaving only the black trunks and limbs! You also might notice how acid rain has eaten away the stone in some cities' buildings and stone artwork. Acidity in rain is measured by collecting samples of rain and measuring its pH.
To find the distribution of rain acidity, weather conditions are monitored and rain samples are collected at sites all over the country. The areas of greatest acidity lowest pH values are located in the Northeastern United States. This pattern of high acidity is caused by the large number of cities, the dense population, and the concentration of power and industrial plants in the Northeast. In addition, the prevailing wind direction brings storms and pollution to the Northeast from the Midwest, and dust from the soil and rocks in the Northeastern United States is less likely to neutralize acidity in the rain.
When you hear or read in the media about the effects of acid rain, you are usually told about the lakes, fish, and trees in New England and Canada. However, we are becoming aware of an additional concern: many of our historic buildings and monuments are located in the areas of highest acidity. In Europe, where buildings are much older and pollution levels have been ten times greater than in the United States, there is a growing awareness that pollution and acid rain are accelerating the deterioration of buildings and monuments.
Stone weathers deteriorates as part of the normal geologic cycle through natural chemical, physical, and biological processes when it is exposed to the environment. This weathering process, over hundreds of millions of years, turned the Appalachian Mountains from towering peaks as high as the Rockies to the rounded knobs we see today.
Our concern is that air pollution, particularly in urban areas, may be accelerating the normal, natural rate of stone deterioration, so that we may prematurely lose buildings and sculptures of historic or cultural value.
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