Question: Is the only way to stop global warming by reducing carbon dioxide emissions to zero? Anything above zero will still cause global warming, is this true?

Petra Cameron answered on 30 Jan 2017:

Ideally we need to bring the levels back to where they were before the industrial revolution – not to zero but to a much much lower level than they are now. We also need to worry about other greenhouse gases such as methane. There will always be some CO2 in the atmosphere – it is released from natural sources such as forest fires too. But to prevent global warming we as humans need to revolutionise the way we live – we will need to change how we travel, how we geneate electricity and how we eat if we want to reduce our levels of greenhouse gas emission sufficiently to prevent more than a small increase in global temperatures.