global warming

March 6, 2017

Does global warming matter? (April 2010)

This is a blog post from April 2010.

The video below aims to answer two questions: (i) Do the causes of global warming matter? (ii) Does global warming itself matter?

February 13, 2017

Compulsory case study: Africa

Africa compulsory case study 

AIM: To develop an understanding of the complexities of economic impacts across the African continent and how it could lead to disasters for poor and vulnerable people.

Background

  • 55 countries
  • 34% of the 15-24 year old population is illiterate 
  • African economies are on the brink of collapse thanks to international debt and to make things worse they are having to cope with some of the malicious impacts of climate change.
  • The continent as a whole is warmer by half a degree than in the 1900s.
  • Most African economies are heavily dependent on agriculture which is heavily on the environment. 
  • Water is already a scarce resource in Africa, in 2007 14 countries were officially declared as water stressed. So decreased rainfall has made conditions much worse than they were before.

What has global warming brought to Africa?

  1. Droughts 
  2. Rainy seasons are unreliable and overall rainfall is decreasing
  3. Rains are more localised – the rain that ended the 2005-2006 drought were not widespread across the whole of the continent

So why are these impacts a problem?

Firstly, the competition for water will increase and this can lead to conflicts especially since major freshwater stores such as the Nile cross countries. Not just conflict but people will become reliant on poor quality water stores which can lead to water-borne disease such as cholera.

How does this affect the economy?

Well as more people become prone to water-borne diseases this puts more stress on healthcare. This puts pressure on the governments budget to provide enough welfare for all these people. Also, if more people are ill then they won’t be able to work to their fullest and this will reduce productivity.

Physical and human impacts on Africa 

Physical Impacts

Human Impacts

Fragile impacts may not survive and 20-50% of species in Africa could face extinction

Reduction in food supply (climate change affects rainfall which affects crop production)

Many low-lying coastal countries in Africa are vulnerable to rising sea levels.

Malaria will increase due to increased humidity and rainfall. This puts pressure on  the health care system.

Coral beaching

Increased cyclones

Deforestation and desertification 

So why is Africa so vulnerable?

Well climate change brings a range of problems all over the globe. However, to make the situation worse Africa has a debt crisis. The have a debt to some of the world’s richest countries, the repayments of these sometimes exceed their entire GNP. In 2007 the G8 wrote off the debt to 18 countries but there is still the vast majority of countries which still have their debt.

One method of coping with this debt is by opening doors to international trade. This means by increasing the production of cash crops (crops sold for income rather than the country’s own food supply). However, this has led to much forest clearance.

According to Oxfam this clearing of forests is likely to worsen. Not just to write off debts but because of global warming.  They argue that extreme weather such as droughts will expose soils to erosion from the wind. The puts stress on land and this kind of stress can lead to desertification e.g. animals have to graze on a smaller piece of land leading to that area of land being over -grazed.

Put all these factors together and we learn that it is Africa’s food security which is under threat and that is a major concern for authorities there. 

Test your definitions…

define the following:

  1. Debt crisis
  2. Food security
  3. Cash crop
  4. Desertification
  5. Coral bleaching 

Answers

  1. This is where many African countries have become so heavily indebted that repayments sometimes exceed their entire GNP.
  2. This is the extent to which a country can rely upon food supplies e.g. upon weather or if unable to grow all its food then the extent that it can rely on imports.
  3. These are crops which are grown for income not domestic food supply.
  4. This is the process when fertile land turns into futile desert
  5. This is the whitening of coral due to stress induced death. There are many causes of this e.g. changes in water temperature
January 31, 2017

Global Warming: Causes

What are the natural and human causes of global warming?

Natural 

Human 

Milankovitch cycles – Changes in the Earth’s axis and orbits.

Methane from animals or paddy fields

Angle of the Earth and axial tilts

Burning fossil fuels

Orbit shape around the sun

Deforestation

Changes in sun’s radiations – Sun spots increase radiation and there are natural fluctuations in solar output

CFCs (chloroflurocarbons) – From fridge and aerosols 

Volcanic eruption –  These can cool global temperatures so the lack of them can increase eruptions.

Nitrous oxides from fertilisers and industrial activities.

Cosmic collisions – These can increase the amount of CO2 in the atmosphere