Natural causes - LDQ format

Level Descriptor Questions (LDQ) Format

Volcanic eruptions are the main cause of global climate change. Do you agree?               [6]

Introduction

-        Disagree. To a large extent. (accept all other possible answers). This essay will discuss about Volcanic eruption as the natural cause, as well as human activities that contributes to a large component of climate change.

Point - Explain how volcanic eruption affects climate.	•        Volcanic eruption causes temporary cooling of the earth for months or years. This affects the climate as temperature drops.
Elaborate - Elaborate on gases released and global dimming.	•        Global dimming: Gradual reduction in the amount of sunlight reaching the earth’s surface. –       Dust particles from eruption form condensation nuclei, creating more cloud cover. –       Dust and ash also reflect away incoming solar radiation.
Examples - Country - Year of eruption - Volcano name	•        For example, Mount Pinatubo eruption lowered temperatures by as much as 0.6°C for as long as two years.
Limitations - Explain that variations in solar output also affect climate change.	However, volcanic eruptions only affects the temperature temporarily, and also causes more of a regional impact than global impact. It also depends on the scale of the eruption to determine the amount of greenhouses gases produced. Additionally, the amount of sunspots also affects the climate change in the world.

Sunspots / Human activities eg deforestation, burning of fossil fuels.

In conclusion, volcanic eruptions causes climate change to a small extent and thus I disagree with the statement. Human activities contributes more to global climatic changes.

LDQ sample for climate

‘The equatorial climate is the most favourable climate for agriculture.’ How far do you agree with this statement? [6]

Introduction

I agree with the statement to a large extent. In this essay, I will discuss the advantages of agriculture in the equatorial climate and the disadvantages of agriculture in the monsoon climate.

Point 1

The equatorial climate is advantageous for agriculture as it has high temperature and rainfall throughout the year.

Elaborate 1

The equatorial climate is dominated by convectional rainfall with large cloud cover. This brings monthly rainfall consistently which favours the growth of crops. The high temperature and humidity throughout the year also indicates a high amount of solar radiation which is necessary for agriculture.

Example 1

In countries like Malaysia and Brazil, there is a high annual rainfall of 2000mm, and precipitation is evident every month. The temperature ranges from 26 to 30 degree Celsius which is high throughout the year.

Point 2

The monsoon climate is not suitable for agriculture as it has a distinct wet and dry season. It has high temperature throughout the year, but a rainfall pattern that fluctuates greatly.

Elaborate 2

This implies that there is only a short time frame for crops to grow before the amount of rainfall peaks at the highest, or drops to the lowest with little rainfall. This extreme fluctuation in the amount of precipitation may cause crops to die even though the temperature of the monsoon climate is consistent throughout the year.

Example 2

In India, during the wet season of May to September, there is high amount rainfall of at least 500mm monthly. However from the dry season of October to April, the rainfall may be as low as little or no rainfall.

Conclusion

In conclusion, both climates has high amount of temperature throughout the year which is ideal for agriculture growth. However the extreme precipitation range of the monsoon climate results in extreme weather conditions like flood or drought which kills the crops. Countries in the monsoon climate can introduce irrigation methods to channel water sources during the dry season so that their agriculture crops can be sustained.

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8. Diagnostic test
9. Temperature
10. Climate Change and Enhanced Greenhouse Effect
11. Natural causes of climate change

- Natural causes - Resource pack page 33

'Deforestation is the main cause of global warming'. How far do you agree with this statement? Support your answer using evidence. [6]

INTRODUCTION


Point 1 - Deforestation
Elaboration
Example

Point 2 - Variation in solar output
Variation in solar output is another factor causing global warming. The sun emits varying amount of solar radiation due to changes in its magnetic field. 

Elaboration
Occurrence of sunspots may cause an increase in the global temperature. Sunspots are cooler regions on the sun’s surface that appear as dark spots. The areas surrounding the sunspots will radiate more energy, which compensates for the lower temperature of the sunspot areas. 

Example
For example, a peak in the number of sunspots in 2000 coincided with higher solar activity. 

CONCLUSION

NATURAL CAUSES OF CLIMATE CHANGE

Variation in solar output

1. Explain how does the varying amount of solar output affect global warming? [3]

•        Magnetic field – The magnetic activity of the sun has a cycle that lasts about 11 years.

•        Sunspots – An increase in solar radiation is due to an increase in sun spots.

–       Areas surrounding the sunspots radiate more energy to make up for the cooler sunspot areas.

. Temperature – With higher solar radiation, earth’s temperatures will increase

Volcanic eruptions

2. Explain how does volcanic eruption affects global temperatures? [4]

a)     Gases released – Sulphur dioxide, carbon dioxide, hydrochloric acid, carbon monoxide, water vapor

b)     Global dimming –Gradual reduction in the amount of sunlight reaching the earth’s surface. Dust particles from eruption form condensation nuclei, creating more cloud cover. Dust and ash also reflect away incoming solar radiation.

c)     Effect on temperature -  Temporarily cools the earth for months or years

d)     Examples - Mount Pinatubo eruption lowered temperatures by as much as 0.6°C for as long as two years.

Climate change and Greenhouse effect

A. Climate Change

Q1. Describe the changes to the Global Climatic pattern from 1800 to 2000. [2]

General increase over the years;

sharp increase in temperatures between 1980-2000

Note : The steeper the gradient of the line, the greater the temperature increase.

Q2. How do you think the increase in Temperature will affect the world? [2]

http://www.youtube.com/watch?v=2_ZQRIsn2pA

The impacts of a one degree change : More hurricanes, More deserts, Food crops destroyed

B. Enhanced Greenhouse Effect

Q3. What is the difference between the Greenhouse Effect and the Enhanced Greenhouse Effect? [4]

•        Greenhouse effect: Natural process in which the gases in the Earth’s atmosphere trap longwave radiation emitted from the earth’s surface [1], warming the atmosphere for us to survive.[1]

•        Enhanced greenhouse effect: Increase in the concentration of greenhouse gases in the atmosphere [1], leading to a rise in global temperatures. Usually a result of human activities [1]

Q4. What are the 4 Greenhouse gases? [4]

Carbon Dioxide, Nitrous oxide, Methane, Chloroflurocarbons

Climograph

Southeast and Southwest monsoon

With reference to Fig. 6, explain how Mangalore, India is affected by Southwest monsoon.                                                         

•Max 3 marks awarded only if student never make reference to Mangalore, India.

•Between June and September, when it is summer in the northern hemisphere.  Air over Central Asia heats up, expands and rises, forming a region of low pressure over the area. 

•During the same period, the southern hemisphere is experiencing winter.  The low temperature causes the air to be cold and dense, exerting a greater force on the earth’s surface.  This results in an area of high pressure over Australia.

•Due to the difference in pressure between Central Asia and Australia, air from Australia moves to the Indian sub-continent and Central Asia as the southeast monsoon winds.  As the winds cross the Equator, the Coriolis effect deflects the winds to the right. 

•These winds become the southwest monsoon winds and warm up as they head for Central Asia.  The warm air picks up moisture as it travels over the Indian Ocean and brings heavy rain to the Mangalore, India. 

March holiday homework

Hi all,

I have decided to cancel the march holiday lesson due to poor attendance. Instead, i will need you to read up on the TEXTBOOK from pages 98 - 108 on your own. Use the textbook to help you complete the following homework in the resource pack.

HW: Resource pack
- Climate Change : Q1,Q2,Q3,Q4
- Natural causes of climate change : Q1(Variation in solar output), Q2 (Volcanic eruptions)

Class test 2 : Term 2 Week 3

Class test (15m)
- 4th April 12.40 pm - 1.20 pm

Topics

- Monsoon

- Climograph

- Greenhouse effect/breezes

- Causes of climate change

Monsoon homework answers

(a)     With reference to Fig. 1, identify the monsoon winds that blow in December in India.	[1]
North-east Monsoon
(b)     Explain the formation of the monsoon wind identified in (i).	[4]
Area of low pressure forms over Australia during summer India is experiencing winter, on the other hand, forming area of high pressure Air moves from India to Australia due to the difference in pressure Coriolis effect deflects the winds to the left when they cross equator, forming the North-East monsoon

                                  

Using your understanding of the topic, identify the monsoon wind shown in Fig. 2 and explain its formation. [4]
It is the SouthWest Monsoon [1m] In June, the southern hemisphere is having winter and the Northern hemisphere is having summer [1m] The wind moves from Southern Hemisphere which is of higher pressure towards the Northern Hemisphere which is of a lower pressure[1m] Due to the Coriolis effect, the winds are deflected to the right in the Northern Hemisphere, which results in the Southwest monsoon winds blowing across India [1m]