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1

1. What three things from volcanic eruptions that have impact on climate?

1. SULPHUR

2. CARBON DIOXIDE

3. OTHER VOLCANIC GASES LIKE CHLORINE

2

1. Gasses emitted from volcanoes

Volcanic eruptions release abundant gas that can cause change.

These include:

- SULPHUR DIOXIDE
- CARBON DIOXIDE
- OTHER VOLCANIC GASES LIKE CHLORINE

3

1. Sulphur dioxide - why is it noxious?

In the atmosphere it reacts with water to produce sulphuric acid. It absorbs and blocks solar radiation causing the Earth to cool.

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1. Carbon dioxide - why is it noxious?

This gas traps solar radiation

5

1. Other volcanic gases such as chlorine?

They deplete the ozone layer.

6

2. Asthenosphere

The lower crust and upper mantle (100 to 250 km deep) that is partially melted. Only about 10% has melted due to pressure induced heat (most of it is close to melting) .

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2. Why is the asthenosphere important?

The asthenosphere is the primary source of magma for volcanoes on the Earth's surface.

8

3. Paul's Volcano

An active stratovolcano (explosive) in Alaska near the Pacific ocean.

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3. Why is Paul's Volcano significant?

It is important because it tends to erupt only during certain times of the year - in the winter.

This regular eruption pattern of the volcano is thought to be caused by higher, sustained sea levels, and therefore more weight at the coast, caused by winter winds blowing from the pacific ocean to the coast.

This additional weight changes the crust in and around the volcano causing it (the crust) to bend differently.

This change in the crust then changes the volcano in such a way that magma reaches the surface more easily.

10

4. Volcano Season

A regular pattern of eruption related to weather and climate.

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4. How does the Volcano Season happen?

The underlying cause is changes in the distribution of weight in the form of water caused by changes in the form of water as part of the water cycle.

In particular this includes:

- Changes in sea level
- Changes in precipitation (rain, snow)
- Changes in glacial ice

12

5. The idea that climate has a significant impact on volcanic activity is based on three factors. Briefly explain each

Climate affects volcanic activity because of the transfer of mass, in particular water. Water, and therefore mass, is transferred by:

1. Precipitation (rain and snow)
2. Formation or melting of glaciers
3. Changes in sea level related to air pressure and wind.