Are human beings responsible for climate change?

Answer 1

The consensus opinion of climate scientists is that humans are "substantially" responsible for global warming. This is a cautious and responsible view that does allow the possibility, not yet demonstrated, that natural forces play a significant role in current warming. Certainly the last ten years have been the warmest globally since instrumental temperatures began in 1850, and the temperature trend is rising faster than in any previous natural period of temperature change.

Answer 2

Although a background level of global warming is natural, keeping the earth at a comfortable temperature suitable for human existence, human activities have contributed to enhanced global warming. Average global temperatures are rising because we, as humans, are adding carbon dioxide to the atmosphere, thereby increasing the concentration by 35 per cent from 260-280 parts per million (ppm) before the start of the Industrial Age, to the present level of over 400 ppm. We do this principally by burning fossil fuels (coal, oil and natural gas), by manufacturing cement and by deforestation.

Carbon dioxide is a greenhouse gas that absorbs infrared heat being radiated from the earth's surface and prevents it from escaping into space. By adding more carbon dioxide above the long-term average level, we are increasing this greenhouse effect, thereby contributing to global warming.

Answer 3

Yes, climate scientists around the world agree that man is responsible for the recent global warming, caused by deforestation and the burning of fossil fuels. If there are fewer trees, then more carbon dioxide is left in the air. If we burn fossil fuel we add extra carbon dioxide that had been safely hidden underground for 300 million years. The carbon cycle can remove the naturally emitted carbon dioxide, but it can't deal with all the extra. This is why the earth is warming and why we are experiencing climate change.