Surely, the impact of human activity is small?
No. Greenhouse gases are produced naturally and commercially. Both types influence climate change. All the greenhouse gases combined (the main ones being water vapour, CO2, methane and nitrous oxide) are only a tiny part of the atmosphere, making up less than 0.5%. Yet it is scientifically proven that these gases trap heat, keeping the planet 30 °C warmer than it would be otherwise and able to sustain life. Any changes in the levels of these gases, such as those recently brought about by human activity, will have a significant effect on global temperatures. Keeping the climate stable is important for the well-being of the Earth. But there is now very strong evidence that man-made greenhouse gases are causing climate change.
