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2. Talk about cause, effect of a certain type of pollution as well as solutions to this problem (water pollution)

Water pollution can be defined as the contamination of a stream, river, lake, ocean or any other stretch of water, depleting water quality and making it toxic for the environment and humans. It can occur in many ways: industrial activities like dumping waste which drains in the fresh water make it polluted; or agriculture activities like using pesticides, herbicides....; and the garbage that we throw everyday. And it effects seriouslly. First, water pollution truly harms biodiversity and aquatic ecosystems, makes the creature sick or even die. Next, it has very negative effects on human health because it is the cause of many diseasessuch as diarrhea, cholera, skin infections.... or dehydration because of lacking of fresh water. Besides, it destroys environmental landscape,..etc. But we can reduce water pollution in many effective ways like reducing the amount of water we use, having green agriculture or throwing rubbish into right places..... Water pollution is a serious problem, but we can solve it if we try hard!

1.

Fifty years ago, the tools we rely upon to communicate today were only science fiction. Today, you can purchase a smartphone and make calls, surf the Web, play games, run applications and accomplish more than most speculative fiction authors dared to dream. So what's next?

In the short term, we'll likely see basic cell phones slowly fade away. As smartphones become more common and less expensive, more people will adopt them. The process is gradual. As with most new technologies, a group of enthusiastic adopters lead the way. Sometimes, the general population will follow the early pioneers -- the compact disc is a good example of such technology. In other cases, the early adopters end up owning technology that becomes obsolete without ever finding wide acceptance -- like LaserDiscs.

Smartphones seem to be in the first category. Products like the Apple iPhone and Google's Android operating system have pushed the smartphone out of the world of gadget geeks and into the mass market. In 2010, the first 4G smartphone for a major carrier in the United States made an appearance. It was the HTC EVO 4G, running on Sprint's WiMAX network [source: CNET]. The 4G network allows for faster data transfer speeds than other networks.

The Internet will continue to play an increasing role in communication. Voice over Internet protocol (VoIP) already plays a large role in several communication products and services. Sites like Facebook and Twitter allow users to communicate with networks of people. With the rise of the Web, people now have a platform from which they can address the world. In the past, only celebrities and politicians could address so many people at one time. Now, anyone with an Internet connection can do the same thing.

This may lead to changes in everything from entertainment to politics. Using the Web as a communication tool, people with aspirations may be able to find an audience more easily than ever before. It may not be long until a relatively unknown person uses the Internet to win enough support to be elected president of the United States.

So far we've looked at some fairly mundane advances in communication. But what about the distant future?

2.

When people think of air pollution, most immediately picture heavy smog drifting over cities and industrial plants.

This is the first and most evident form of air pollution, but it’s not the only one.

Let’s begin today’s discussion by defining the term air pollution at a broader level. Air pollution in its most basic definition is the introduction of harmful substances into the Earth’s atmosphere.

These substances linger and cause many adverse effects. As you know, humans and other living creatures rely on the atmosphere for respiration. When air quality is dampened by pollution, immediate and longer term consequences take place.

Pollution has been known to cause allergies, disease, damage to crops, and in extreme cases, even death.

In addition, air pollution creates an imbalance in the natural gases that make up our Earth’s atmosphere. These imbalances slowly aid in the depletion of the Ozone layer, an essential region of the stratosphere that soaks up most of the sun’s damaging ultraviolet (UV) rays.

As the Ozone depletes, the rate of global warming increases. If enough air pollution clutters our environment, it creates the danger of more rapid deterioration of the Ozone layer.

You can see the trouble this may cause.

It’s important that we, as citizens of the world, fully understand the causes, effects, and possible solutions of air pollution so that we can make an educated decision for Earth’s future.

Causes

There are many causes of air pollution. For sanity’s sake, we’ve done our best to categorize them at a more general level.

Before we get into the different causes, let’s take a quick step back and look at the different variations of air pollution.

First, there’s invisible and visible air pollution. The smog you see lingering over a city is a good example of visible pollution.

Invisible pollutants aren’t as noticeable, but they can be just as deadly, if not more so. Examples of invisible pollutants include nitrogen oxides, sulfur dioxide, and carbon monoxide, to name a few.

Carbon monoxide inhaled and introduced into the human blood stream spells trouble if the pollution is a high enough concentration.

Digging down even deeper, air pollution can be split into primary and secondary pollutants.

Primary pollutants, such as sulfur dioxide, are ones directly released into the atmosphere. Secondary pollutants, like smog for example, are the result of primary pollutants intermingling with the already existing particles in the atmosphere.

Without any further ado, let’s get into some specific causes of air pollution.

1. Vehicle Exhaust Fumes.

The number one source of air pollution in city environments is vehicle exhaust fumes, which happen to release high amounts of carbon monoxide. It’s no surprise then that carbon monoxide also happens to be the largest air pollutant in the United States.

Millions of vehicles are operated on a daily basis in the US alone, each one leaving its own carbon footprint on the environment. This is why hybrid and fully electric vehicles are making a splash in the automobile marketplace.

People are looking to rely less on fossil fuels to power their cars, leading to less toxic emissions into the environment.

2. Fossil Fuel-Based Power Plants.

In addition to vehicle exhaust pollution, fossil fuels also present a wider scale problem when they’re burned for energy in power plants.

Chemicals like sulfur dioxide are released during the burning process, which travel straight into the atmosphere. These types of pollutants react with water molecules to yield something known as acid rain.

This is one of the reasons that alternative energy sources, such as nuclear, solar, and wind are being explored in greater detail. They tend to release much less pollutants into the environment to produce equivalent amounts of energy.

3. Exhaust from Industrial Plants and Factories.

Similar to exhaust being released from vehicles, heavier machinery located inside big factories and industrial plants also emit pollutants into the air.

Industrial plants can be found pretty much everywhere in the world, so the spreading of air pollution is basically global.

4. Construction and Agricultural Activities.

On a daily basis, dirt and dust is kicked up into the atmosphere from excavating and demolition type construction activities.

Switching the focus to agricultural activities, ammonia is a frequent byproduct that just so happens to be one of the most dangerous gases in our environment.

There are also plenty of nasty chemicals that get placed into the atmosphere from pesticides and fertilizers, which are being used at increasingly higher rates.

5. Natural Causes.

When people think pollution, they almost always blame other people. Let’s not forget that the Earth is one of the biggest polluters itself, though.

Volcanoes, forest fires, and dust storms are nature-born events that dump massive amounts of air pollution into the environment.

It’s often debated that humans don’t come close to volcanoes when it comes to air pollutants, but we’ll leave that for the readers to decide.

6. Household Activities.

Forget about outdoor pollution. What about the pollution that takes place inside our own homes?

Common household chemicals, notably bleach, without proper ventilation is a primary source of indoor air pollution.

Smoking tobacco through the use of cigarettes and cigars also releases toxic pollutants into the air.

It’s often easier to think of outdoor pollution as the primary danger on a wide scale level, but don’t dismiss the little everyday activities that also impact our health.

Effects

Now that we know the culprits of air pollution, let’s start discussing the harmful effects.

There are many different types of effects that air pollutants can cause. For one, there’s the human health factor to consider.

If humans are at risk, then other forms of wildlife and organic creatures are in danger as well.

Then there are the effects on the planet and its atmosphere.

In the paragraphs to follow, we’ll take a closer look at all of air pollution’s effects.

1. Accelerated Global Warming.

This is a green energy discussion, so let’s tackle this one first.

Earlier on, you learned about the Ozone layer and its role in protecting our planet. Air pollution directly accelerates the rate at which global warming happens by depleting the Ozone layer.

Global warming refers to the increased temperatures Earth continues to experience. These higher temperatures lead to the melting of the polar ice caps and icebergs, which elevates sea levels and creates concern for the human race.

2. Human Respiratory and Heart Concerns.

Air pollution is known to cause irritation in the eyes, lungs, nose, and throat. It creates respiratory problems and exacerbates existing conditions such as asthma and emphysema.

When continually exposed to air pollution, humans become at higher risk for cardiovascular disease. Air filled with toxins can have a number of adverse effects on the arteries, and have even been a contributor to heart attacks.

3. Wildlife Endangerment.

Most diseases and conditions that humans are susceptible to, animals are as well. Air pollution creates many of the same issues that humans face.

Heavily polluted areas force inhabitants to seek new homes, which can negatively impact the ecosystem.

Toxic chemicals, which we’ll discuss in the next bullet, also deposit over surfaces of water that can lead to the endangerment of marine life animals.

4. Acid Rain.

When air pollution, specifically sulfur oxides and nitrogen oxides, are released into sky through fossil fuel burning, it creates the phenomenon known as acid rain.

Water, high in the atmosphere, combines with these chemicals and becomes acidic in nature. It then scatters the ground, disguised as normal rainfall.

Acid rain has been known to cause harm to humans and animals alike, and even damage crops.

Solutions

Up until this point, we’ve covered all the bad of air pollution. Now let’s get onto the good.

Well, there’s actually not much good to say for air pollution, but there are a number of positive ways it can be dealt with.

Understanding the causes and effects proves to be important so that we can determine how best to combat it.

Reducing the use of fossil fuel powered automobiles is clearly something that can help. Same with finding unique ways to reduce energy consumption.

Let’s dig a little deeper into common solutions for preventing and minimizing air pollution.

1. Minimize the Use of Fossil Fuel Powered Automobiles.

As a leading contributor to air pollution, it only makes sense that a vehicle-based solution appears first on this list.

One way to do this is by switching to a hybrid vehicle, or better yet, one that runs on fully electric.

Other ways include taking public transportation, carpooling with friends and colleagues, or even riding a bike to your destination.

2. Be Mindful of Energy Consumption.

When you’re leaving home, be sure to turn off the lights, TV, and any other electronic appliances.

Fossil fuel plants are a major cause of air pollutants, and the less energy you need, the less we have to rely on those plants to generate electricity.

This also means turning to energy efficient devices when possible. Fluorescent lightbulbs over the course of their lifespan can reduce energy consumption while adding significant savings to your pocket.

3. Become a...

Nhiều lỗi quá:) Sửa:
Water pollution can be defined as the contamination of a stream, river, lake, ocean or any other water stretch, depleting water quality and making it toxic for the environment and humans. It can occur in many ways: industrial activities like dumping waste which drains in the freshwater make it polluted, or agriculture activities like pesticides, herbicides, and the garbage that we throw every day. And it affects seriously. First, water pollution truly harms biodiversity, and aquatic ecosystems make the creature sick or even die. Next, it has very adverse effects on human health because it is the cause of many diseases such as diarrhoea, cholera, skin infections or dehydration because of lacking freshwater. Besides, it destroys the environmental landscape, etc. But we can reduce water pollution in many practical ways like reducing the amount of water we use, having green agriculture or throwing rubbish into the right places. Water pollution is a severe problem, but we can solve it if we try hard!