Major Environmental Issues
1. Global warming:
This has been considered as the most pressing environmental issue. Climate change is real and it is influenced by human activities through the production of green house gases such as methane and carbon dioxide. Global warming is necessitated by the ability of our ecosystem to respond to climate change due to compromised environment. Global warming has the effect of melting polar ice caps, displacing people form tropical and coastal islands and can ultimately threaten the survival of human race.
Climate change is a complex phenomenon, and its full-scale impacts are hard to predict far in advance. But each year scientists learn more about how climate change is affecting the planet and our communities, and most agree that certain consequences are likely to occur if current trends continue.
In addition to affecting our water resources, energy supply, transportation, agriculture, and ecosystems, the United States Global Change Research Program concludes that climate change also poses unique challenges to human health, such as:
· Significant increases in the risk of illness and death related to extreme heat and heat waves are very likely.
· Some diseases transmitted by food, water, and insects are likely to increase.
· Certain groups, including children, the elderly, and the poor, are most vulnerable to a range of climate-related health effects.
These impacts will result in significant costs to our families and the economy.
Climate Change, Water, and Risk
Climate change will have a significant impact on the sustainability of water supplies in the coming decades. A new analysis, performed by consulting firm Tetra Tech for the Natural Resources Defense Council (NRDC), examined the effects of global warming on water supply and demand in the contiguous United States. The study found that more than 1,100 counties -- one-third of all counties in the lower 48 -- will face higher risks of water shortages by mid-century as the result of global warming. More than 400 of these counties will face extremely high risks of water shortages.
Extreme Weather: Impacts of Climate Change
When it comes to connecting the dots between climate change, extreme weather and health, the lines are clear.
The earth is saying something with record heat, drought, storms and fire. Scientists are telling us this is what global warming looks like.
It's time to listen – and take action. There's plenty we can do.
Carbon pollution is the main reason our planet is getting hotter, increasing the chances of weather disasters, drought and flood and hurting our health.
There are solutions. For starters, we can cut carbon pollution by reducing our dependence on fossil fuels and increasing our use of clean, renewable energy. And we can implement policies that help us prepare for flooding, drought, storms and other consequences of climate change.
2. Air Pollution
Air pollution means the presence of one or more unwanted substances in air. Air pollutants have a negative impacts on humans, animals and plants, and on air quality.
The most frequently present categories of air pollutants are sulphur oxides, nitrogen oxides, Volatile Organic Compounds (VOC) and small dust particles (aerosols).
The most frequently present categories of air pollutants are sulphur oxides, nitrogen oxides, Volatile Organic Compounds (VOC) and small dust particles (aerosols).
What causes air pollution?
The main sources of air pollution are the industries, agriculture and traffic, as well as energy generation. During combustion processes and other production processes air pollutants are emitted. Some of these substances are not directly damaging to air quality, but will form harmful air pollutants by reactions with other substances that are present in air.
Examples of large-scale air pollutants are VOC (Volatile Organic Compounds) and small dust particles. When large concentrations of these substances are emitted this negatively affects ecosystems, materials and public health.
Emissions of nitrous oxide (N2O) mainly stem from agriculture, because nitrogen in soils can easily be denitrified by bacteria. Nitrous oxide is emitted during the denitrification process. Additionally, the application of (artificial) fertilizers causes emissions of ammonia (NH3), nitrogen oxides (NOx) and methane CH4), a greenhouse gas.
The agricultural sector is known for its extensive use of pesticides. This application causes emissions of many toxic chemicals.
Industrial processes vary greatly and as a result there are many different chemical wastes. The industries are responsible for emissions of carbon monoxide, carbon dioxide, sulphur dioxide, nitrogen oxides, small dust particles, VOC, methane, ammonia and radioactive radiation.
During energy generation chemicals such as methane are released into the air as a result of oil and natural gas extraction. The combustion of coal and natural gas for electricity production causes the release of sulphur dioxide, nitrogen oxides and carbon dioxide into the air.
Traffic is held responsible for one-third of the greenhouse gas emissions. Emissions caused by traffic are mainly those of carbon dioxide, carbon monoxide, nitrogen oxides, VOC and small dust particles.
Consumers are also partly responsible for air pollution. Firstly because the products they use have caused air pollution during their production and distribution and secondly because heating of houses and offices causes chemicals release into the air. When people use paints or cosmetics VOC is released and perspiration, pet fertilizer use and cleanser use cause ammonia emissions. Last but not least, many chemicals (carbon dioxide, carbon monooxide) are emitted during smoking.
Examples of large-scale air pollutants are VOC (Volatile Organic Compounds) and small dust particles. When large concentrations of these substances are emitted this negatively affects ecosystems, materials and public health.
Emissions of nitrous oxide (N2O) mainly stem from agriculture, because nitrogen in soils can easily be denitrified by bacteria. Nitrous oxide is emitted during the denitrification process. Additionally, the application of (artificial) fertilizers causes emissions of ammonia (NH3), nitrogen oxides (NOx) and methane CH4), a greenhouse gas.The agricultural sector is known for its extensive use of pesticides. This application causes emissions of many toxic chemicals.
Industrial processes vary greatly and as a result there are many different chemical wastes. The industries are responsible for emissions of carbon monoxide, carbon dioxide, sulphur dioxide, nitrogen oxides, small dust particles, VOC, methane, ammonia and radioactive radiation.
During energy generation chemicals such as methane are released into the air as a result of oil and natural gas extraction. The combustion of coal and natural gas for electricity production causes the release of sulphur dioxide, nitrogen oxides and carbon dioxide into the air.
Traffic is held responsible for one-third of the greenhouse gas emissions. Emissions caused by traffic are mainly those of carbon dioxide, carbon monoxide, nitrogen oxides, VOC and small dust particles.
Consumers are also partly responsible for air pollution. Firstly because the products they use have caused air pollution during their production and distribution and secondly because heating of houses and offices causes chemicals release into the air. When people use paints or cosmetics VOC is released and perspiration, pet fertilizer use and cleanser use cause ammonia emissions. Last but not least, many chemicals (carbon dioxide, carbon monooxide) are emitted during smoking.
How does air pollution form?
Air pollution can form in various ways. Chemicals are emitted during many different human activities. In the atmosphere these chemicals can react with other chemicals to more dangerous substances. Air pollutants often have properties that are harmful to the environment.
The weather plays an important role in the formation and disapearance of air pollution. This is mainly influenced by wind and temperatures. Air pollutants can be transported by wind, causing a pollution to spread widely. Rain can remove pollutants from air, causing soil and water pollution. Sunlight can aid the convertion of air pollutants to different substances.
Chemicals can come from various sources, and are formed during different processes. Air pollution can be divided in categories according to the source it is derived from:
- Biological air pollution, such as pollens, small insects and microrganisms (bacteria, fungi, yeasts and algae)
- Physical air pollution, such as sound, smell, thermal pollution and radioactive radiation
- Chemical air pollution, such as ozone, aerosols and ammonia
Air pollution is caused by both human and natural sources. Human sources are traffic, agriculture or industry, as was mentioned before. Natural sources are be dust storms, volcanic eruptions and emissions from plants.
Air pollution undergoes a number of processes:
- Emission (contaminants are released into the air)
- Transport (contaminants are transported to different locations through air)
- Exchange (compounds react with other compounds in air)
- Distribution (contaminants are distributed in air)
- Immission (contaminants maintain in a certain area)
- Deposition (contaminants are deposited in a certain area, on the soil or on objects)
The weather plays an important role in the formation and disapearance of air pollution. This is mainly influenced by wind and temperatures. Air pollutants can be transported by wind, causing a pollution to spread widely. Rain can remove pollutants from air, causing soil and water pollution. Sunlight can aid the convertion of air pollutants to different substances.
Chemicals can come from various sources, and are formed during different processes. Air pollution can be divided in categories according to the source it is derived from:
- Biological air pollution, such as pollens, small insects and microrganisms (bacteria, fungi, yeasts and algae)
- Physical air pollution, such as sound, smell, thermal pollution and radioactive radiation
- Chemical air pollution, such as ozone, aerosols and ammonia
Air pollution is caused by both human and natural sources. Human sources are traffic, agriculture or industry, as was mentioned before. Natural sources are be dust storms, volcanic eruptions and emissions from plants.
Air pollution undergoes a number of processes:
- Emission (contaminants are released into the air)
- Transport (contaminants are transported to different locations through air)
- Exchange (compounds react with other compounds in air)
- Distribution (contaminants are distributed in air)
- Immission (contaminants maintain in a certain area)
- Deposition (contaminants are deposited in a certain area, on the soil or on objects)
Acid deposition
Acid deposition is not merely characterized as acid rain; it can also be snow and fog or gas and dust. Acid deposition mainly forms during fossil fuel combustion. When emissions of sulphur dioxide and nitrogen oxides come in contact with water, they will become sulphuric acid and nitric acid.
It causes:
Acid deposition is not merely characterized as acid rain; it can also be snow and fog or gas and dust. Acid deposition mainly forms during fossil fuel combustion. When emissions of sulphur dioxide and nitrogen oxides come in contact with water, they will become sulphuric acid and nitric acid.
It causes:
-Availability of nutrients and metal spores is likely to decrease.
- When acidity is high more metals will dissolve in water. This can cause surface water to become polluted, which has serious health effects on aquatic plants and animals. For example, high aluminum (Al) concentrations can complicate nutrients uptake by plants. This makes aluminum one of the prior causes of forest decay. Mercury can be dispersed by transport through surface water, causing it to accumulate in fish. Mercury can bio magnify up the food chain, to be taken up by humans eventually.
- Buildings and monuments may be damaged through erosion. Sulphur dioxide breaks down limestone by reacting with calcium carbonate, causing limestone to absorb water during rainfall. Limestone will than fragment.
- When acidity is high more metals will dissolve in water. This can cause surface water to become polluted, which has serious health effects on aquatic plants and animals. For example, high aluminum (Al) concentrations can complicate nutrients uptake by plants. This makes aluminum one of the prior causes of forest decay. Mercury can be dispersed by transport through surface water, causing it to accumulate in fish. Mercury can bio magnify up the food chain, to be taken up by humans eventually.
- Buildings and monuments may be damaged through erosion. Sulphur dioxide breaks down limestone by reacting with calcium carbonate, causing limestone to absorb water during rainfall. Limestone will than fragment.
Eutrophication
Eutrophication is caused by an increase in plant nutrients in water. The higher availability of nutrients causes certain water plants, such as algae and duckweed, to grow so extensively. This blocks sunlight supplies to water. The plants also use all available oxygen supplies, which will not be renewed because heterotrophic plants and bacteria need light to perform photosynthesis. Eutrophication causes ecosystem disruption. Nitrogen pollutants such as nitrogen oxides and ammonia contribute to this problem.
Eutrophication is caused by an increase in plant nutrients in water. The higher availability of nutrients causes certain water plants, such as algae and duckweed, to grow so extensively. This blocks sunlight supplies to water. The plants also use all available oxygen supplies, which will not be renewed because heterotrophic plants and bacteria need light to perform photosynthesis. Eutrophication causes ecosystem disruption. Nitrogen pollutants such as nitrogen oxides and ammonia contribute to this problem.
Smog
Smog is a combination of the words smoke and fog. We can distinguish two separate types of smog, summer smog and winter smog.
Photochemical smog, or summer smog, mainly consists of ozone. It is a brown, oxidising fog. The causes of photochemical smog are nitrogen oxides and VOC, which stem from traffic and industries.
Smog is a combination of the words smoke and fog. We can distinguish two separate types of smog, summer smog and winter smog.
Photochemical smog, or summer smog, mainly consists of ozone. It is a brown, oxidising fog. The causes of photochemical smog are nitrogen oxides and VOC, which stem from traffic and industries.
Ozone loss
Ozone is created everywhere in the atmosphere through chemical reactions under the influence of UV-light. Ozone is decomposed under the influence of visible light and UV-A light. During ozone decomposition an oxygen-poor molecule is released, which aids the breakdown of ozone. There are a number of compounds that catalyse ozone decomposition. Examples are hydroxide (OH), nitrogen oxides, chlorine (Cl) and bromine (Br).
Ozone is created everywhere in the atmosphere through chemical reactions under the influence of UV-light. Ozone is decomposed under the influence of visible light and UV-A light. During ozone decomposition an oxygen-poor molecule is released, which aids the breakdown of ozone. There are a number of compounds that catalyse ozone decomposition. Examples are hydroxide (OH), nitrogen oxides, chlorine (Cl) and bromine (Br).
Greenhouse Effect results to:
- Melting of polar ice and oceanic expansion. This results in flooding of coastal areas, swamps, wetlands and river deltas. Some small islands may even vanish completely consequential to flooding
- Melting of polar ice and oceanic expansion. This results in flooding of coastal areas, swamps, wetlands and river deltas. Some small islands may even vanish completely consequential to flooding
- Cold and warm gulf stream alteration caused by desalination of the Atlantic Ocean, possibly causing a new Ice Age
- Increase in number and severity of tropical storms and cyclones
- Flooding and erosion of agricultural plots. This damages crops and soils and decreases harvest
- Major shifts in ecosystems and decreasing biodiversity
- Evaporation of water supplies, causing drinking water scarcity
- Saltwater penetration of groundwater zones
- More extreme weather, causing hotter and drier summers and colder winters
- More contagious diseases because the environment is more positive for pathogens and some dangerous insects, such as the malaria mosquito
- Increase in number and severity of tropical storms and cyclones
- Flooding and erosion of agricultural plots. This damages crops and soils and decreases harvest
- Major shifts in ecosystems and decreasing biodiversity
- Evaporation of water supplies, causing drinking water scarcity
- Saltwater penetration of groundwater zones
- More extreme weather, causing hotter and drier summers and colder winters
- More contagious diseases because the environment is more positive for pathogens and some dangerous insects, such as the malaria mosquito
Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing that drinks or uses or lives (in) it. When humans drink polluted water it often has serious effects on their health. Water pollution can also make water unsuited for the desired use.
Several classes of water pollutants
1. disease-causing agents. These are bacteria, viruses, protozoa and parasitic worms that enter sewage systems and untreated waste.
2. oxygen-demanding wastes; wastes that can be decomposed by oxygen-requiring bacteria. When large populations of decomposing bacteria are converting these wastes it can deplete oxygen levels in the water. This causes other organisms in the water, such as fish, to die.
3. water-soluble inorganic pollutants, such as acids, salts and toxic metals. Large quantities of these compounds will make water unfit to drink and will cause the death of aquatic life.
4. nutrients; they are water-soluble nitrates and phosphates that cause excessive growth of algae and other water plants, which deplete the water's oxygen supply. This kills fish and, when found in drinking water, can kill young children.
In most manufacturing processes a lot of heat originates that must be released into the environment, because it is waste heat. The cheapest way to do this is to withdraw nearby surface water, pass it through the plant, and return the heated water to the body of surface water. The heat that is released in the water has negative effects on all life in the receiving surface water. This is the kind of pollution that is commonly known as heat pollution or thermal pollution.
The warmer water decreases the solubility of oxygen in the water and it also causes water organisms to breathe faster. Many water organisms will then die from oxygen shortages, or they become more susceptible to diseases.
The warmer water decreases the solubility of oxygen in the water and it also causes water organisms to breathe faster. Many water organisms will then die from oxygen shortages, or they become more susceptible to diseases.
Eutrophication means natural nutrient enrichment of streams and lakes. The enrichment is often increased by human activities, such as agriculture (manure addition). Over time, lakes then become eutrophic due to an increase in nutrients.
Eutrophication is mainly caused by an increase in nitrate and phosphate levels and has a negative influence on water life. This is because, due to the enrichment, water plants such as algae will grow extensively. As a result the water will absorb less light and certain aerobic bacteria will become more active. These bacteria deplete oxygen levels even further, so that only anaerobic bacteria can be active. This makes life in the water impossible for fish and other organisms.
Eutrophication is mainly caused by an increase in nitrate and phosphate levels and has a negative influence on water life. This is because, due to the enrichment, water plants such as algae will grow extensively. As a result the water will absorb less light and certain aerobic bacteria will become more active. These bacteria deplete oxygen levels even further, so that only anaerobic bacteria can be active. This makes life in the water impossible for fish and other organisms.
Typical rainwater has a pH of about 5 to 6. This means that it is naturally a neutral, slightly acidic liquid. During precipitation rainwater dissolves gasses such as carbon dioxide and oxygen. The industry now emits great amounts of acidifying gasses, such as sulphuric oxides and carbon monoxide. These gasses also dissolve in rainwater. This causes a change in pH of the precipitation – the pH of rain will fall to a value of or below 4. When a substance has a pH of below 6.5, it is acid. The lower the pH, the more acid the substance is. That is why rain with a lower pH, due to dissolved industrial emissions, is called acid rain.
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