2. Global warming: an increase in world temperatures, caused by an increase in carbon dioxide around the Earth. Glaciers: persistent bodies of ice formed by the accumulation of snow. Gas: one of the three fundamental states of matter; a substance such as air, which is not solid or liquid. Greenhouse: a glass building used for growing plants. Greenhouse effect: the warming of the air around the Earth as a result of the Sun’s heat being trapped by pollution. Greenhouse gases: gases released in the atmosphere that absorb and emit radiation.

3. Human activity: human work that contributes to upset the balance of the carbon cycle. Heat: an increase in temperature. Hot: having a high temperature.

4. Infra-red: infra-red light gives out heat but cannot be seen. Infrared radiation (I.R.): electromagnetic radiation with longer wavelenghts than those of visible light. Imbalance: when two things are not the right size in relation to each other.

5. Methane: a chemical compound, the main component of natural gas and also a greenhouse gas. Minimize temperature increase: to diminish the temperature of the Earth.

6. Natural causes: happenings produced by nature. Natural greenhouse gases: gases originated in nature, which cushion the earth’s surface, causing a global heat increase.

7. Ozone: an unstable, poisonous allotrope of oxygen, that is formed naturally in the ozone layer. It is made up of 3 atoms of oxygen. Ozone layer: it is a layer in the Earth’s atmosphere containing high concentrations of ozone. This layer absorbs ultra-violet radiation. Ozone hole: it is an annual thinning of the ozone layer over the Antarctic, caused by stratospheric chlorine.

8. Pollutants: substances which contaminate the atmosphere with undesired effects. Predictability: something behaving or happening in the way that you expect. Pollution: damage caused to air, water, soil, by harmful chemicals and waste.

9. Recycle: to extract useful materials from garbage or waste. Reduce: to limit, to decrease the quantity of something.

10. Sea levels: the levels of the ocean surface used as a standard in reckoning with land elevation or sea depths. Storm: a period of very bad weather with heavy rain, strong wind, and often lightning.

11. Weather: condition of the atmosphere at a certain place and time, with reference to temperature and the presence of rain, sunshine, wind. Warm: slightly hot, especially in a pleasant way.