Climate Change

Question 1

Evidence for Climate Change

Answer 1

FOSSIL EVIDENCE:
1-Ice core analysis
examines oxygen isotopes trapped in ice cores giving accurate reading of the Earth’s past temperatures
2-Deep sea sediment cores
contains remains of organisms that retain oxygen isotopes to work out past temperatures.
3-Pollen found in Pete Bogs
anaerobic environments, no oxygen, analyse the pollen found there and trace back to what plants used to grow then what the climate was like.

RECENT EVIDENCE:
1-Melting glaciers/ice sheets(over recent years)
2-Seasonal changes(plants are blooming earlier each year, bird migration is changing)

=global warming is happening so fast that scientists think it must be due to humans.

Question 2

Define Global Warming

Answer 2

The recent warming of the Earth’s atmosphere (last 150yrs) due to anthropogenic activity (humans)

Question 3

Natural Causes of climate change:

Answer 3

1-Change in the Earth’s orbit
2-Variations in the Sun’s heat output
3-Volcanic activity

CHANGES IN THE EARTH’S ORBIT:
Eccentricity when the Earth’s orbit around the sun changes shape every 100,000 yrs (inter-glacial periods & ice ages) from a rugby to a football
round = closer to sun (inter-glacial)
stretched = further from the sun (glacial/ice age)

VARIATIONS IN THE SUN’S HEAT OUTPUT:
Sun spots: dark patches on the surface of the sun
more sun spots = more heat output = warmer Earth
less sun spots = less heat = colder Earth

VOLCANIC ACTIVITY:
-When a large eruption occurs (Mt Tambora 1815) it releases so much ash and gas into the atmosphere it reduces the Earth’s global temperature by up to 2’C !
= global dimming- when the ash blocks the sun’s rays (reducig temperatures)
=sulphur dioxide released into the atmosphere reacts with water becomng Sulfuric acid that mirror the sun’s rays back out reducing temperature even more!

Question 4

Human Causes of climate change

Answer 4

1-Use of fossil fuels
2-Agriculture
3-Deforestation

USE OF FOSSIL FUELS:
-causes increased amounts of CO2 production
=60% ENHANCED greenhouse effect
=cars, vehicles

AGRICULTURE:
-livestock are one of the largest producers of methane
-rice production produces lots of Methane.(fields are flooded, anaerobic respiration, more methane)
-rapid increase in meat production

DEFORESTATION:
-less CO2 being reabsorbed
=more going into the atmosphere to contribute to the ENHANCED greenhouse effect

Question 5

Mitigation
=REDUCING the effects of climate change

Answer 5

1-Alternative energy production
(wind, solar, wave)
2-Carbon capture/storage
(CO2 is captured and shoved down an abandoned empty oil well)
3-International agreements
(COP meetings, helping keep countries lower their impact on the environment and stop temperatures rising)

Question 6

Adaption
=Finding ways to LIVE WITH climate change

Answer 6

1-Managing water supply
(e.g. in the Himalayas)
=build dams that trap water in the Summer
=that water freezes in the Winter
=it is stored and ready to melt in the next Spring ready for crops

2-Changing Agricultural Practices
(by growing different crops)
=many farms in the UK are switching to wine production as the hotter temperatures are perfect for growing grapes.
(investing in water storage)
= large ponds, resevoirs
to collect and store water for summer.

3-Reducing the risk from rising sea levels
(The Maldives)
= Sea Walls & Artificial Islands
-The Maldives are a collection of islands and are developed highly along the coast so are vulnerable to flooding.