1. Climate and Change
Unit 1 revision session

2. Defining terms...
Weather – the day-to-day condition of the atmosphere Climate – the average weather over 30 years Interglacial – warm periods in the earth’s climate Glacial – cooler periods in the earth’s climate

3. What do the graphs tell us?

5. How do we know climate changes?
Fossilised plants, animals and pollen
Landforms
Ice sheet samples (ice cores)
Old photographs/paintings
Diaries, books and newspapers
Recorded dates of regular events e.g. Harvests, tree blossom, migrations etc

6. Ice Age Glacials last about 80,000-100,000 years
Some glacials were so cold the Earth plunged into an ice age
The last ice age was30,000-10,
000 years ago
Ice m thick, it caused
The Earth’s crust to sag, sea level
fell by 100m

7. How Climate has changes in the past
Eruption Theory
Sunspot Theory
Orbital Theory

8. Scales of Climate Change
Description: A look at climate change over a range of timescales. Long term changes include changes in the suns output, the orbit of the earth, the tilt of the earth's axis and wobble in the earth's axis of rotation. It ends with a look at how changes in albedo and increased urbanisation and industry have influenced global warming through increased pollution.

9. Changing the Atmosphere

10. Contributors to the Enhanced Greenhouse Effect

11. Climate has changed in the Past
Greenland Vikings
The Little Ice Age
Medieval warm period meant:
Greenland much warmer: good trade links, farms and population
The Little Ice Age meant that life became harsh:
Sea ice prevented trade
Less food caught due to shorter summer = starvation
Livestock could not be supported = ...
The Little Ice Age brought a halt to prosperous Europe
Longer winters
Colder
More Rain
Failing crops
PEOPLE ADAPTED!

12. Climate and Ecosystems
Mass extinction: animals/plants completely die out
Ecosystems break down as climate changes
Climate
Sunlight
Precipitation
Air
Carnivores
Plants
Herbivores
Megafauna Extinction:
Climate change & humans
Water
Soil
Rock

13. Emissions

14. Impact

15. The Future? Shrinking ice caps Rising sea levels
Increasing global temperatures
Floods
Droughts
Heatwaves
Storms
Hurricanes

16. In summary...
CARBON DIOXIDE is a greenhouse GAS. These gases in the ATMOSPHERE keep the planet comfortably WARM. Human activities are producing more greenhouse gases which POLLUTE the atmosphere. This is causing the ENHANCED GREENHOUSE EFFECT and seems to be leading to GLOBAL WARMING.

17. Impacts of a warmer UK Advantages (benefits/pros)
Disadvantages (costs/cons)
Heating and gritting costs could fall in winter
More UK-based holidays
Fewer deaths of the old and infirm during winter
New crops mean new opportunities
More land could be farmed
More common drought and water shortage (summer)
More illness e.g. Heat stroke and skin cancer
Melting road surfaces and buckling railway lines
Changes in crops grown
Extinction of some plants and animals

18. UK Summary

19. Acting on climate change
Stern Review 2006 – ‘spend now or pay later’
Kyoto Protocol 1997 – international agreements to reduce carbon emissions
Agenda 21 – Act local think global

20. Wider Impacts
Example: EGYPT