Global WarmingGlobal Warming

Learning objectives:Learning objectives:

1.1. To understand the greenhouse To understand the greenhouse effect and why global warming effect and why global warming occursoccurs

2.2. To understand the impact that To understand the impact that global warming could have upon global warming could have upon the Earththe Earth

Global warming!!!Global warming!!!

• Increase in the Earth’s temperature- Increase in the Earth’s temperature- over the next 100 years the over the next 100 years the temperature is predicted to rise by 2-3 temperature is predicted to rise by 2-3 degrees C.degrees C.

• But why could this happen??!But why could this happen??!

• The The GREENHOUSE GREENHOUSE EFFECTEFFECT

The Greenhouse EffectThe Greenhouse Effect

• The earth is The earth is surrounded by surrounded by GREENHOUSE GREENHOUSE GASESGASES

• They let in heat from They let in heat from the sun but prevent the sun but prevent much of it from much of it from escapingescaping

• This layer acts like a This layer acts like a greenhouse!!! greenhouse!!!

What produces these What produces these greenhouse gases?greenhouse gases?

• Basically: economic activity since the Basically: economic activity since the Industrial Revolution 200 years agoIndustrial Revolution 200 years ago

• Burning fossil fuels produces carbon Burning fossil fuels produces carbon dioxidedioxide

• Fossil fuels: oil, natural gas, coalFossil fuels: oil, natural gas, coal

Greenhouse gasesGreenhouse gases

• As more greenhouse gases are As more greenhouse gases are produced, more of the sun’s energy produced, more of the sun’s energy is prevented from escaping and is prevented from escaping and GLOBAL WARMING occursGLOBAL WARMING occurs

• Main greenhouse gas: Carbon dioxideMain greenhouse gas: Carbon dioxide

Impact of global Impact of global warmingwarming

• Glaciers meltGlaciers melt

• Rise in sea level because of glaciers meltingRise in sea level because of glaciers melting

• Increased floodingIncreased flooding

• More extreme weatherMore extreme weather

• Increased desertificationIncreased desertification

• Change in vegetationChange in vegetation

• Some plants and animals extinct in certain Some plants and animals extinct in certain areasareas

Effects of global warming:Effects of global warming:Retreat of glaciers and valleys; Retreat of glaciers and valleys; vegetationvegetation

Global warming and effect upon Global warming and effect upon landscapelandscape

Lakes and glacial valleysLakes and glacial valleys

Millions battle South Asia Millions battle South Asia floods, 12/7/04floods, 12/7/04

• over two million people over two million people had to flee their homes had to flee their homes in India and Bangladeshin India and Bangladesh

• 1/3 Bangladesh 1/3 Bangladesh affected,3 million affected,3 million people marooned, people marooned, 1000s searching for 1000s searching for shelter and several shelter and several killed. killed.

(www.bbc.co.uk)(www.bbc.co.uk)

Therefore:Therefore:

•Global warming is a Global warming is a MAJOR issue that will MAJOR issue that will affect all of us over the affect all of us over the next century!!!next century!!!