1.Earth Day
Earth Day was started in 1970. It was organized to help raise environmental awareness to the general public.It helped spark the creation of the Environmental Protection Agency.
By the year 2000 there will be6.3 billion people on the planet. There was almost twice as much land devoted to urban life in 1990 than there ws in 1970.
The Earth Day provides a special day to remind the population to take care of the Earth.
2.Going Green
When Jeffrey Hollander launched his seventh generation live of products ten years ago, the market for nontoxic household cleaners and recycled paper products was virtually nonexistent. Today, it's a booming businness.
The niche is environmentally friendly,or so called green products.
A green product is one that has less impact on the environment. So that means that it might use less resources, it may create less waste and be more evergy efficient for example.
An average home might have an evergy bill of 1300 dollars a year. If all the products, all the appliances in the home were Energy Star, that home could save about 30% a year, and for the average home in the U.S. that might be around $400 a year.
3. Description of the earth:
Earth means many things to the people who live on it. To a farmer, Earth is rich soil. To a road builder, Earth means mountains of hard rock. For a sailor, Earth is water as far as the eye can see. A pilot's view of Earth may include part of an ocean, a mountain, and patches of farmland. An astronaut speeding through space sees the Earth's round shape and the outline of lands and oceans.
4. Car Pollution
Today, there are more than 630 million cars in the world. U.S. drivers own a third of these vehicles, which in turn produce a third of the nation's greenhouse gases -- emissions (primarily carbon dioxide) that accumulate in our upper atmosphere and cause global warming. We're seeing the effects in weird weather, melting glaciers, and rising oceans that pose an immediate threat to many island nations.
Refining, distributing, and burning a gallon of gasoline produces about 30 pounds of carbon dioxide. If every car in the U.S. were replaced by one that was 10 mpg more fuel-efficient, carbon dioxide emissions would be reduced by 250 million tons per year, and the nation's annual contribution to global warming would be cut by nearly 20 percent.
Pollution
The most serlous result of air pollution is from its harmful effect, on human
health. Both gases and particuiates burn people's eyes and irritate the lungs.
Particulates can settle in 1ungs and worsen such respiratory diseases as asthma and
bronchitis. Some expers even beIieve that particulates may cause such diseases as
cancer emphysema and pneumonla. '
Air pollution also harm plans. Poisonoas gases in the air will turn into acid
rain which spread over thou'ands of square kilometers and restric the growth and
even,ually kill nearly all kinds of plants.
Polluted air can corrode such hard and strong materials as concrete and steel .
which are widely used in building houses and constructions. In some cities. statues
and other sculptares and art obiects outdoors have dislntegrated as a result of
erosion by polluted air.'
But advance in controlling exhaust from automobiles has been limited. Filters
used inare not efficient in absorbing poisonous gase. and particulates To reduce
hazardous. experts resort to new types of engines and new fuel.. The idea and
prototypes of engincs have long been proposed and tested. Fuel in the turbine engine
can be burned almostly completely . producing more power, releasing less unburned
hydrocarbons and almost no carbon monoxide
The harnessing of the new energy
With the increasing concern over hazardous environmental consequences caused by
burn-ing fos.il fuel. fuel cells now win favor in Japan and the U. S. . Experts
predict that fuel cellswill eventually replace nuclear plants in 20 to 30 years,
supplying eiectricity to households.and they will be used in cars and in space
stations, as the major engines. Researchers are working hard to reduce their volume
and cost so that they can meet the requirements of future energy resources in
prac,ical use
Making use of tides and waves to produce electricity is feasible and
economical. Many idieas have been proposed. for example, building a dam at the mouth
of a bay to trap water in the bay when tbe tide comes and tben when it ebbs,
driving turbines with that water to genterate electricity. To make use of the
kinetic energy of waves, a series of buoys Linked together in rows offshore absorb
kihetic energy when the waves push them back and forth.This incessant movement can
drive hydraulic mackines to generate electricity.
Turning wind power into electricity is nothing new, today wind-powered
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