More Environmental Problems

Question 1

The level of carbon dioxide in the atmosphere is doing what?

Answer 1

Increasing causing climate change.

Question 2

Why is the level of carbon dioxide in the atmosphere increasing?

Answer 2

Because of the large amounts of fossil fuels humans burn.

Question 3

What is the scientific consensus about the extra carbon dioxide?

Answer 3

It is causing the average temperature pf the Earth to increase - global warming.

Question 4

What is global warming?

Answer 4

Gradual increase in the overall temperature of the earth’s atmosphere.
Generally attributed to the greenhouse effect caused by increased levels of carbon dioxide.

Question 5

What negative things can global warming cause?

Answer 5

Changing in rainfall patterns.

Severe flooding due to polar ice caps melting.

Question 6

What causes global dimming?

Answer 6

Tiny particles that are released when fuels are burned.

Question 7

In the last few years what have scientists been measuring?

Answer 7

How much sunlight is reaching the surface of the Earth and comparing it from the last 50 years.

Question 8

What have the scientists found out about the sunlight hitting the surface of the Earth?

Answer 8

They found that in some areas 25% less sunlight has been reaching the surface compared to 50 years ago.
Called this global dimming.

Question 9

What do the scientists think causes global dimming?

Answer 9

Particles of soot and ash that are produced when fossil fuels are burnt.
The particles reflect sunlight back into space or they help produce clouds that reflect sunlight back into space.

Question 10

However what do some scientists believe about global dimming?

Answer 10

They don’t believe the change is real and blame it on inaccurate recording equipment.

Question 11

Name alternative renewable fuels?

Answer 11

Ethanol.
Biodiesel.
Hydrogen gas.

Question 12

How can ethanol be produced?

Answer 12

From plant material so its known as a biofuel.

Question 13

How is ethanol made?

Answer 13

By fermentation of plants and is used to power cars in some places.
Its often mixed with petrol to make a better fuel.

Question 14

Name a pro about ethanol?

Answer 14

The CO2 released when its burnt was taken in by the plant as it grew, so its carbon neutral.
The only other product is water.

Question 15

Name a con about ethanol?

Answer 15

Engines need to be converted before they’ll work with ethanol fuels and ethanol fuel isn’t widely available.
There are worries that as demand for it increases farmers will switch from growing food crops to growing crops to make ethanol - increase in food prices.

Question 16

What is biodiesel?

Answer 16

Another type of biofuel.

Question 17

How is biodiesel produced?

Answer 17

Produced from vegetable oil such as rapeseed oil and soybean oil.
Biodiesel can be mixed with ordinary diesel fuel and used to run a diesel engine.

Question 18

What is a pro about biodiesel?

Answer 18

It is carbon neutral.
Engines don’t need to be converted.
It produces much less sulphur dioxide and particulates than ordinary diesel or petrol.

Question 19

What is a con about biodiesel?

Answer 19

We can’t make enough to completely replace diesel.
It’s expensive to make.
It could increase food prices.

Question 20

What can hydrogen gas be used for?

Answer 20

To power vehicles.

Question 21

Where do you get hydrogen gas from?

Answer 21

You get the hydrogen from the electrolysis of water.
There is plenty of water about it just takes electrical energy to split it up.
Energy comes from a renewable source.

Question 22

Name a pro about hydrogen gas?

Answer 22

Hydrogen combines with oxygen in the air to form just water, its very clean.

Question 23

Name a con about hydrogen gas?

Answer 23

You need a special, expensive engine and hydrogen isn’t widely available.
You still need to use energy from another source.
Hydrogen’s hard to store.