It is imperative that there is a wider understanding of the enhanced greenhouse effect - that is, the process of global warming that is now taking place because of human activities. The combustion of fossil energy, the release of various industrial gases, deforestation, and certain agricultural practices, are between them changing the composition of the Earth's atmosphere - with implications that are awesome, in both scope and scale.

The warming is already leading to climate change, causing serious impacts upon biodiversity, the economy and people's lives. There is still time to avoid very large-scale climatic shifts, and the very much worse effects of them, but time is running out. That is why public understanding is needed now, so that policies and actions to reduce emissions can be implemented.

Tony Juniper is author of Spix's Macaw: The Race to Save the World's Rarest Bird (buy this book from Amazon (UK) or Amazon (USA)), and coauthor of Parrots: A Guide to Parrots of the World (buy this book from Amazon (UK) or Amazon (USA)).