Global Warming

C.5.NoS1 Transdisciplinary—the study of global warming encompasses a broad range of concepts and ideas and is transdisciplinary. (4.1)

C.5.NoS2 Collaboration and significance of science explanations to the public—reports of the Intergovernmental Panel on Climate Change (IPCC). (5.2)

C.5.NoS3 Correlation and cause and understanding of science—CO2 levels and Earth average temperature show clear correlation but wide variations in the surface temperature of the Earth have occurred frequently in the past. (2.8

Greenhouse gases

C.5.U1 Greenhouse gases allow the passage of incoming solar short wavelength radiation but absorb the longer wavelength radiation from the Earth. Some of the absorbed radiation is re-radiated back to Earth.

C.5.AS2 Discussion of the evidence for the relationship between the increased concentration of gases and global warming.

Kinds of greenhouse gases

C.5.AS3 Discussion of the sources, relative abundance and effects of different greenhouse gases.

C.5.G1 Greenhouse gases to be considered are CH4, H2O and CO2.

How greenhouse gases warm the climate

C.5.AS1 Explanation of the molecular mechanisms by which greenhouse gases absorb infrared radiation.

C.5.U3 Greenhouse gases absorb IR radiation as there is a change in dipole moment as the bonds in the molecule stretch and bend.

Other environmental impact of greenhouse gases

C.5.U2 There is a heterogeneous equilibrium between concentration of atmospheric carbon dioxide and aqueous carbon dioxide in the oceans.

C.5.AS5 Discussion of pH changes in the ocean due to increased concentration of carbon dioxide in the atmosphere.

C.5.Aims1 Aim 6: The equilibrium between aqueous and gaseous carbon dioxide could be experimentally investigated.

C.5.U4 Particulates such as smoke and dust cause global dimming as they reflect sunlight, as do clouds.

International Controls

C.5.AS4 Discussion of the different approaches to the control of carbon dioxide emissions.

Carbon Footprint

C.2.U7 A carbon footprint is the total amount of greenhouse gases produced during human activities. It is generally expressed in equivalent tons of carbon dioxide.

C.2.AS6 Calculations of the carbon dioxide added to the atmosphere, when different fuels burn and determination of carbon footprints for different activities.

C.2.Aims3 Aim 7: Many online calculators are available to calculate carbon footprints.

Sustainability measures

C.5.IM1 This issue involves the international community working together to research and reduce the effects of global warming. Such attempts include the Intergovernmental Panel on Climate Change (IPCC) and the Kyoto Protocol which was extended in Qatar.

C.5.ToK1 Some people question the reality of climate change, and question the motives of scientists who have “exaggerated” the problem. How do we assess the evidence collected and the models used to predict the impact of human activities?

C.5.Aims3 Aim 8: Discussions of climate change and green chemistry raise awareness of the ethical, economic and environmental implications of using science and technology.

C.5.Aims2 Aim 7: Computer modelling is a powerful tool by which knowledge can be gained about the greenhouse effect.