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Global warming
What is Global Warming?
Greenhouse gases
The effects of Global Warming
What People can do
What Governments are doing
Find out more
Global warming is one of the greatest threats to humanity that we have possibly ever faced. The general scientific opinion is that Global warming has already started and that it has the potential to affect agriculture, sea levels, coastal; erosion, out climate and weather, the ecosystems of our planet and rain fall levels. Your first assessment in year 9 is on this topic and offers you a first insight into environmental geography - the geography of studying how human activities affect the environment, and what the consequences of that are for our species. You can download the assessment task sheet here.
The Earth's atmosphere, a thin blanket of gases, protects the planet
from the harshest of the sun's rays (watch
an animation). The atmosphere, by trapping the Earth's warmth, keeps
rivers and oceans from freezing. Carbon dioxide and water vapour are the
most important gases in creating the insulating or "greenhouse effect"
of the atmosphere.
The
greenhouse effect is a natural occurrence that keeps Earth's average
temperature at approximately 15°C
Without the natural greenhouse effect temperatures on Earth would be
much lower than they are now, and the existence of life on this
planet would not be possible. The global average temperature would
drop 33 °C from its current 15° to -18°C. The Earth would become an
ice planet. However, too many greenhouse gases in Earth's atmosphere
could increase the greenhouse effect. This could result in an
increase in mean global temperatures as well as changes in rainfall
patterns.
Watch a movie on how global warming works.
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Greenhouse Gases - Carbon Dioxide
A greenhouse gas is an atmospheric gas which warms the lower atmosphere by
absorbing thermal radiation (heat energy).
Carbon Dioxide (CO2) is one of those gases.
The amount of CO2 released into the atmosphere in the next 30 years
is expected to double or triple. The number of cars in operation around the
world will double by the year 2030. This can be seen below. Methane is
another greenhouse gas that scientists are worried about.
The rate of global warming and sea level rise will be higher than previous
predictions during the next century. Estimated land losses range from 0.05% for
A 1M (3
feet) sea-level rise would affect 6 million people in Egypt, with 12% to 15% of
agricultural land lost, 13 million in Bangladesh, with 16% of national rice
production lost, and 72 million in China and "tens of thousands" of hectares(1
hectare =2.47 acres) of agricultural land. This is based on new information
released by the Intergovernmental Panel on Climate Change.
Global warming is at the root of the increase, say the researchers, as the
Earth’s climbing temperatures melt the Arctic sea ice and
Changing ice sheets
Global Impacts of the greenhouse effect
1. Water expands when it's heated and oceans absorb more heat than land, so sea
levels would rise.
2. Places that usually get lots of rain and snowfall might get hotter and drier.
3. There would be more droughts making hard to grow crops.
4. Less water would be available for drinking, showers and swimming pools.
5. Some plants and animals might become extinct because of the heat.
6. Hurricanes, tornadoes and other storms which are caused by changes in heat
and water evaporation may get more common
There are ways you can help cut greenhouse gases and help
stop global warming.
Re-cycle glass bottles, jars, newspapers and magazines and tin cans. Save them and take them to local re-cycling centres. Compost food waste.
Try and buy products that don't use much packaging.
Only fill the kettle up with the amount of water you need to boil that time.
Ask whoever does your washing to use the machine at 40 degrees, this helps
conserve power.
Switch lights off when you're not in the room
Cycle to places!
Have showers instead of baths.
Use Renewable energy sources such as
wind power
a) Read the CBBC guide to Global warming
b) Find out more about the impacts by clicking on
this fantastic interactive map from National Geographic
c) Calculate your
Carbon footprint by clicking on the calculator
d) Some people and scientists do not believe in Global Warming. Research the following sites;
Which side of the argument do you believe? Say why in a couple of paragraphs.
e) Some global warming games
f) Play Planet Protectors and guard the world against Global Warming!
g) Play operation climate control for GCSE level, from DEFRA