global warming what is it?. global warming is the gradual increase of the temperature of the earth,...

Global Warming

What Is It?

Global warming is the gradual increase of the

temperature of the earth, which in turn causes changes in climate.

Earth hasWarmed by about

1 degreeFarenheit over

The past 100 years.

What is Climate?• It is the long-term

average (usually 30 years) of a particular region’s weather pattern.

• At the peak of the last ice age (18,000 years ago), The temperature was only 7 degrees colder than it is today, and glaciers covered much of North America!

So You See…Even a small increase in temperature over a long

time can change the climate.

When the climate changes, there may be big

changes in things that people depend on. These things include the level of the oceans and the places

where we plant crops. They also include the air

we breathe and the water we drink.

What Might Happen to Human Health?

Global warming may cause an increase in heat stress and other heat related health problems.

Ecological disturbances, air pollution, changes in food and water supplies, and coastal flooding may also affect human health.

Poor people, poor countries, very young children, and the elderly will run the highest risks without the money and resources needed to cope.

How will it Effect Our Ecosystems?

• If future climate changes occur as rapidly as predicted, an upset in the delicate balance of rainfall, temperature, and soil type could seriously endanger many plants and animals and their

habitats.

What About our Sea Level?

• Global warming may make the sea level become higher. Warmer weather makes the glaciers melt and adds more water to the ocean.

• Warm temperatures also make water expand. This takes up more space and the level of the sea rises.

• It could rise as much as 3 feet during the next century!

• What problems could this cause?.........

Coastal flooding could cause saltwater to flow into areas where salt is harmful,

threatening plants and animals in those areas.

Flooding and beach erosion could affect oceanfront property and reduce the quality of drinking water.

What about our Crops and Food Supply?

Global warming may make the Earth warmer in cold places, giving people in those places a chance to grow crops in new areas.

BUT… It may also bring droughts to many

parts of the world. This would leave people without enough to eat because they couldn’t grow the food that they need.

What is the Greenhouse Effect?

The greenhouse effect is what causes global

warming.

It is called “greenhouse effect” because it is the same process that keeps

the air inside greenhouses (and parked cars) warmer

than the air outside.

The glass in greenhouse windows is transparent to visible light radiated

from the sun.

This light heats the surface of materials inside the

greenhouse, which emit longer wave-length infrared

radiation.

Infrared radiation cannot penetrate the glass and is

trapped…

Causing the inside air to warm up.

Water vapor, clouds, carbon dioxide, & other gasses in

our atmosphere act like the greenhouse glass by

preventing some of the infrared radiation emitted by

the earth to escape into space.

These are called“greenhouse gasses”.

Where Do Greenhouse Gasses Come From?

Volcanoes

Forest fires, crop burning,and clearing of rain forests

Automobiles and other internal-combustionengines

CFCs used in refrigerators,air conditioners and aerosol spray cans.

Because the levels of these gasses are increasing, more

and more of the heat radiated by the earth’s

surface is trapped in the atmosphere…

…causing our world to heat up.

The Greenhouse Effect

• Solarradiationpassesthroughthe clearatmosphere.

Most radiationis absorbedby the earth’s surface andwarms it.

Some solar radiationis reflected bythe earth and the atmosphere.

Some of the infrared radiationpasses through the atmosphere,and some is absorbed and re-emitted in all directions by Greenhouse gas molecules. The effect of this is to warmthe earth’s surface and the lower atmosphere.

The greenhouse effect is important. Without it, the Earth would not be warm

enough for humans to live.

But, if it becomes Stronger, it could makeThe Earth warmer than

Usual. Even a little Extra warming may cause

Problems for humans, Plants, and animals.

WE CAN

MAKE

A

DIFFERENCE!

Global warming may be a big problem, but there are many

little things we can do to make a difference.

If we try, most of us can do our part to

reduce theamount of greenhouse gasses that we put into

the atmosphere.

Many greenhouse gasses come from

things we do every day.

SAVE ELECTRICITY

Whenever we use electricity, we help put greenhouse gases into

the air. By turning off lights,

the television, and the computer when you are through with them, you

can help a lot.

BUS

WALK

BIKE

You can save energy by sometimes taking the bus, riding a bike, or waking.

It’s fun and a great way to reduce

greenhouse gases.

Trees absorb Carbon dioxide from the air.

Plant Trees

RECYCLE

Cans, bottles, plastic bags, and newspapers.When you recycle, you send less trash to the

landfill and you help save natural resources, like trees, oil, and elements

such as aluminum.

Cars are an important part of life for most people. But they

also cause pollution and release a lot of greenhouse gases into

the air.

Fortunately, there are some cars that are better

for the environment…

These cars can travel longer on a smaller

amount of gasoline. They don’t pollute as much,

either.

Using these kinds of cars can help reduce

the amount of greenhouse gases in

the air.

Solar energy is energy that comes from the

sun.It can be usedto heat homes,buildings, water, and to make electricity.

Today, more than 200,000 houses in the U.S. use this type of energy.