Evidence for Climate Change


Long Term


Glaciers advance when temperatures are cool and retreat when temperatures are warm. Glaciers leave behind moraines, unconsolidated glacial debris, which contain organic data which can be accurately dated. From 1940s to 1970s evidence shows that glaciers were retreating i.e. warm temperatures. From the 1970s to 1980s there had been stable growth i.e. cool temperatures. And from the 1980s to present there has evidence that glaciers have been retreating i.e. our planet is warming.

Ice cores

Air from Greenland and Arctic ice sheets can be sampled from bubbles trapped in the ice as it was laid down over thousands of years ago.  Carbon dioxide level from the former atmosphere can be reconstructed. This evidence shows that in the past carbon dioxide emissions have been very low, as low as 180ppm. When this evidence is put against rise in temperatures global warming seems to be happening!

Medium Term 

Dendrochronology (Tree rings)

Dendrochronology examines trees and their growth. For example, a thick and fat tree ring means the soil and conditions were fertile hence good rainfall. Whereas, narrow trees indicate poor and low rainfall conditions. So just as with vegetation we can work out the climate of a period of a time as climate affects rainfall. Evidence shows that in the last 50 years ago that temperatures have been 1.5-2 degrees higher than the median and higher than ever before in 7000 years.


Palynology allows scientist to examine climate change through pollen analysis. From this we can infer past climates – up to thousands of years. Evidence from this kind of data shows a steep rise in temperature from1900s to present of about 1degree.

Paintings, poems and diaries

These evidence show that there was a mini ice age between 1000-1850. Then from 1850 to present we can just see evidence for warm conditions. 

French grapes

Records of dates from French grape harvests have usually been used to identify warm and cold periods. From the reconstruction of this data we have seen several warm summers like those of 1900s. However, Summer 2003 heatwave was by far the warmest of them all. Is this evidence for climate change? 

Recent Times

Polar ice

The ice sheets of Greenland, the Canadian Arctic and Antarctica are aerially monitored continually. As we are all aware that evidence shows that these ice sheets are melting quicker than anticipated. This is claimed to have something to do with increased temperatures caused by climate change.


Analysis of vegetation through a time period gives evidence for climate change. This is because a change in climate affects precipitation and how well plants cope.We are witnessing extreme examples of this e.g. desertification in Africa.


1. What is Palynology?

2. What does evidence from polar ice caps show?

3. What is dendrochronology?

4. What does evidence from Glaciers show?

5. How does ice cores provide evidence for global warming? What is the evidence?


1. Palynology is the study of pollen to work out climates of different periods in history.

2. Evidence from polar ice caps shows that ice sheets are melting quicker than we anticipated.

3. Dendrochronology is the study of tree rings to work out climates of the past.

4. Evidence from glaciers shows that from the 1980s to presents glaciers have been retreating i.e. climate is getting warmer.

5. Ice core allow us to measure the amount of carbon dioxide that has been in the atmosphere is the past. This shows that in the past co2 emissions have been so little some as low as 180ppm. This shows a positive correlation with temperature increases.

Kantian Ethics Revision Quiz

Questions (answers below)

1. What Century did Immanual Kant formulate his ethical theory and what nationality was Kant?


2. What quote can be used to sum up his theory?

3. Distinguish between the categorical and hypothetical imperative and give examples.

4. Why is the moral law, according to Kant, categorical?

5. How many formulations does he give of the categorical imperative, what are they and why does Kant give them?

6. Explain the formulations of the categorical imperative – what do they mean?

7. How many example of the first formulation are they? and what are they?

8. What is the distinction between duty and inclination?

9. By doing our duty what do we achieve?

10. Give 3 strengths and weaknesses of Kantian Ethics.


1. 18th C and he was German.

2. ‘Two things, above all others, fill the mind with ever increasing awe and wonder: the starry heavens above and the moral law within”

3. The Hypothetical Imperative looks to an outcome e.g. ‘Do your revision and you will get an A’ and the Categorical Imperative is an absolute command which does not look to an outcome e.g. ‘Do your revision’.

4. Because it was hypothetical it would not be universal – so if it said be moral so you can go to heaven it would be changeable and not universal as some people may not wish to go to heaven.

5. Three: (i) Universalisability (ii) Means to an end and (iii) Kingdom of ends – these are three ways given to understand the same moral law – categorical imperative.

6. Universalisability – only commit to an action that if the rest of the world did would be logical and sustainable. Means to an end – do not use people as a mere means to an end, rather you should respect and give then the same respect you give yourself. Kingdom of ends – if as a lawmaker of the world you could put your action into legislation then the action is moral. 

7. 4 – 2 are perfect duties (contradiction in conception) – do not commit suicide and do not commit false-promising and 2 are imperfect duties (contradiction in the will) – fulfil your own potential and gives others happiness.

8. Duty is what we ought to do and inclination is what we want to do (they don’t always conflict).

9. Goodwill because we eliminate selfish interests.

10. See post on strengths & weaknesses. 

Quiz on Act and Rule Utilitarianism

Please find answers below.

1. What is the Hedonic Calculus and another name for it?

2. Distinguish between higher and lower pleasure giving examples.

3. Which utilitarian theory focuses upon the quantity of pleasure and which on the quality of pleasure?

4. What are 4 components of the hedonic calculus?

5. What does Bentham believe is the supreme moral good and Mill? Does Mill agree?

6. If you pick a lower pleasure over a higher pleasure what are you said to have?

7. What is Mill’s famous quote (hint. think pig)

8. How would you describe Utilitarianism?

9. What are three strengths of Utilitarianism (Act or Rule)?

10. What are three Weaknesses of Utilitarianism (Act or Rule)?



1. Felicific Calculus –  this is a calculation used by the universal hedonists to calculate how much pleasure an action produces.

2. Higher pleasure are those of the mind e.g. feelings, imagination and intellectual pursuits. Lower pleasures are bodily pleasures e.g. sex, drinking and eating.

3. Bentham’s Act utilitarianism focuses upon the quantity of pleasure and Mill’s Rule utilitarianism focuses upon the quality of pleasure.

4. Any 4 from: (i) Remoteness (ii) Certainty (iii)Fecundity (iv)Purity (v)Intensity (vi)Duration (vii) Extent

5. Bentham believes the supreme moral good is happiness and Mill disagrees saying it is justice.

6. An infirmity of the mind.

7. “It is better to be a human being dissatisfied than a pig satisfied; better to be Socrates dissatisfied than a fool satisfied”.

8. Secular, Consequentialist and Teleological theory.

9 and 10. For list of strengths and Weaknesses see my other post.

Word Classes

1. What is an indefinite article? (2)
2. What is the opposite to an indefinite article and what is its function? (3)
3.How many types of adjectives are there? (1)
4. What are the types of adjectives called and what is their function? Give example (6)
5. How many types of common nouns are there? And what are they? (4)
6. What is an adverb? (1)
7. What words describe the position/location of something? Give an example (2)
8. How many types of conjunction are there? What are their functions? (8)
9. ‘Komilla’ ‘Wall Street’ are examples of what words? (1)
10.What is a determiner and give an example? (2) 



1. It is a non-specified determiner.(1) It tells us nothing about the noun. They are ‘A’ or ‘An’ (1)
2. Definite article is the opposite to an indefinite article.(1) It is a specified determiner, it particularises a noun.(1) For example ‘The dog’ as opposed to ‘A dog’. (1)
3. There are two types of adjectives.
4. Attributive (1) – they come before the noun (1) – e.g. ‘The CLASSIC shirt’ (1)
Predicative (1) – they come after the noun (1) e.g. ‘The skirt is BEAUTIFUL’   (1)
5. There are two types of common nouns; abstract (1) – describe feeling and intangible things e.g. ‘joy’ (1)
Concrete (1) – they describe tangible things(1) e.g. ‘book’
6. An adverb is a word which describes the verb e.g. ‘she SOFTLY whispered’ (1)
7. Prepositional words (1)  e.g. ‘on’ ‘by’ (1)
8. There are four; Additional (1) – they allow us to add extra information (1) e.g. ‘and’
Temporal (1) – these describe the time aspect (1) e.g. ‘then’
Casual (1) – these describe the relationship between the two sets of information e.g. ‘because’
Adversative (1) they allow us to show the other side of the argument (1) e.g. ‘but’
9. Proper nouns (1)
10. They precede nouns and refer directly to them (1) e.g. ‘a’ ‘an’ ‘the’ ‘this’ ‘their’

Price Elasticity of Demand

Price elasticity of demand = PED

What is price elasticity of demand?
It is the responsiveness/sensitivity of demand to a change in price.


How do economists calculate price elasticity of demand?
PED = % Change in Quantity Demanded
                       % Change in Price


How do we interpret price elasticity of demand values?
Price elasticity of demand values are always negative because the show that price and demand have an inverse relationship.


If PED is < -1 :
If PED is smaller than minus one then this implies that the demand is elastic.  For example, if the price of a good rose by 10% the quantity demanded  would decrease by more than 10%. Airline tickets are a good example because they are elastic.


If PED is between 0 and -1 :
This means that the demand is inelastic. For example if the price of a good increased by 10% then the quantity demand would decrease by less then 10%. A good example of this is food as they have relatively inelastic demand.


If PED = -1 :

Then this means the demand is unitary elastic. This is the rarest out of all the elasticities. It means that if a price of the good rises by 10% the quantity demanded will decrease by 10%
To understand the graphical representation of PED, please see my post on the three types of elasticities.

Test yourself (Answers found at the bottom)


1. If price increases from 10 to 12 pence and the price elasticity of demand is -0.5. The quantity demanded was 500 units. What will it be now?
a) 550 units
b) 500 units
c) 450 units
d) 490 units
2.If price elasticity of demand is unit then a fall in price:
a) Reduces revenues
b) Increases revenues
c)Leaves revenues unchanged
d) Reduces costs




1. c) This means that any given percentage fall in price leads to an increase in quantity demanded that is half as much; a 20% price increase will reduce the quantity demanded by 10%. This means the  quantity demanded will be 450 units.
2. c) This means the percentage change in quantity demanded equals the percentage change in price so price changes will not alter the revenue.

A great video to help you with this: http://www.youtube.com/watch?v=4oj_lnj6pXA&feature=related 

Also why not check out some further notes in pdf style (not I have not created this file) : http://www.osc-ib.com/ib-revision-guides/pdf/economics-hl-1.pdf

Positive & Normative Economics


As an economist it is vital to be able to distinguish between positive analysis and normative analysis.
For the exam you will be required to tell if a statement is positive or normative.

So here is how it goes…

Positive economics is facts and figures. They are statements which can be verified and tested.For example if I tell you that Burberry shares have gone up 16.2%, this is a positive statement because you can go out and test it.

So the definition for positive statements you need to know is: it is a statement that is testable or verifiable. It is a fact or assertion.
N.B – Remember in the example to give an example if you get a chance.

On the other hand, normative analysis is based on opinions – what in economics we call “value judgements”. An easy way to recognise them is to look for words like ‘ought’ and ‘should’. For example, if I say that the company Superdry should not be in the FTSE 250 then this is a normative statement because it contains the word“should” and it is my personal opinion. It cannot be tested or verified.

An example of a normative statement which does not contain should or ought is : “Some critics are calling for government intervention as rents are becoming unfairly high” – this is in fact taken from a past exam marks scheme. The reason why this is normative is because of the adjective ‘unfairly’ what is unfair to one person is not to another. The fact that someone can disagree with the statement is another easy way to tell the if the statement is normative.

For the exam this definition you need to know is: It is a value judgement which cannot be tested or verified.


This is a great quiz to test your knowledge for the first section of economics including positive and normative analysis: