Human Activity & Climate Change
- Human population is increasing and with it the global demand for food, water, consumer goods, housing and energy which are supplied with greater and more widespread industrialization.
- This creates more waste so more landfill sites are needed which increases the amount of methane by decomposition.
- The increased energy demands are met in most cases by the burning of fossil fuels which produces CO2:
Fossil fuel + oxygen → energy + H2O + CO2
- Added to this is the effect of deforestation on the amount of CO2 as large areas of forested land is being destroyed for building and agricultural activities.
- Plants and trees remove CO2 during photosynthesis:
6CO2 + 6H2O → C6H12O6 + 6O2
- Hence their removal increases the amount of atmospheric CO2 as there are less plants available to remove it during photosynthesis.
- Increasing agricultural activities also cause an increase in methane production.
- By analysis of the percentage of CO2 in the atmosphere and the changes in temperature over several hundred years, the evidence for the effects of CO2 on global temperature is convincing.
- There is a clear correlation between both factors as shown in the graph below.
Graph showing the steady increase in atmospheric CO2 since 1700
Graph showing the steady increase in temperature from when accurate records exist
Uncertainty & Historical Accuracy
- Advances in science and technology mean current levels of CO2 and global temperatures can be determined with a high degree of accuracy.
- Historical data is much less accurate due to the lack of accurate instrumentation and methods.
- Fewer locations would also have been measured due to the lack of satellites and transport.
- There are some methods to estimate past levels, which include:
- Analysis of the fossil record.
- Analysis of trapped gas bubbles and tree rings.
- The ice sheets also trap valuable samples of past atmospheric conditions.
- Unfortunately, these methods, while providing at least some data, are not as precise as modern day techniques nor do they provide data which is representative on a global scale.
- The complexity of the Earth’s climate and contributing factors make it a difficult task to produce a working model that clearly shows the link between global warming and Greenhouse gases.
- This and other difficulties have led to hype and speculation in the media in recent times.
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Morgan’s passion for the Periodic Table begun on his 10th birthday when he received his first Chemistry set. After studying the subject at university he went on to become a fully fledged Chemistry teacher, and now works in an international school in Madrid! In his spare time he helps create our fantastic resources to help you ace your exams.