climate and change Flashcards
describe the eruption theory and give an example
eruptions pump ash and sulphur dioxide into atmosphere, some spreads up above earths surface stopping as much sunlight on earth creating a cooling effect
eg. 1991 mount pinatubo released 17 million tonnes of sulphur dioxide planet cooled 0.5 degrees for a year
describe the sunspot theory and give an example
Black spots appear on areas of the suns surface, more spots means more solar energy fired towards earth, increasing temperature
eg. 1947 greatest ever
describe the orbital theory and give an example
the orbit changes small amount once every 100,000 years which affects the amount of sunlight on earth
eg. Ice ages were 5-6 degrees cooler than today
describe asteroid theory and give an example
asteroid collides with earth, releasing huge amounts of vaporised materials into atmosphere which blocks out sunlight causing a potential temperature drop then a warming effect
eg. extinction of dinosaurs 65 million years ago
describe the impact of a short term historical event on people
little Ice age-cold period in northern Europe which took place in 1315
•Crops didn’t grow – so people had to go hungry ‘great famine’ 1317 to 1325
•Winters were very cold and summers were very short
•10 to 20% of peasant farmers died of hunger
describe the impact of major climatic changes in geological timescale
extinction of megafauna-
• after Little ice age climate warmed
• many animals had to migrate to new areas best suited to them
•It was hard to find the right plants to eat
•this disrupted food chains leading to eventual extinction
•Woolly mammoth
describe the UK climate today
- mild and wet – temperature Maritime
- winter temps – highest in southwest
- Precipitation highest in West
- Snow most common in interior
describe and explain why the UK climate might change in the future
- more air masses from North – more storms and colder winters
- melting of Arctic ice may weaken the North Atlantic drift
- North Atlantic current likely to move – reducing sea temperatures and less rainfall
what are the human activities leading to climate change?
• Burning fossil fuels - releases carbon dioxide into atmosphere
eg. cars heating manufacturing
• landfills and agriculture – increasing methane levels
eg. cattle
both activities release gases into atmosphere which trap any heat leaving and re-radiate it back down to earth increasing temperature
explain the projections for global temperature and sealevel rise
temperature change-
• average temperature will increase by just under 2°
• average temperature will increase by 3°
• average temperature will increase by 4.6°
Uncertainty – temperature change
• future population change
• future energy sources
• future economic growth
Sealevel rise-
•Increase 0.2-0.5m
•increase 0.2-1m
•increase up to 1.8m
what are the economic and environmental impacts of future climate change in the UK
economic-
•drought and water shortages could become more common
•in winter heating and road gritting costs would fall
•more people would holiday in UK
•new crops- new sales opportunities for farmers
environmental-
•farmers might have to find crops that need less water and more sunshine
•more land could be farmed at higher altitudes
what are the economic and environmental impacts of future climate change in Egypt
economic-
•farming hit- loss of natural vegetation
•drought and low water supply
environmental-
•flooding - less land for agriculture
•poor quality soils for farming