Reef threat ‘must be faced now’

There are not one but two major emissions problems that society confronts today.

One of these is well known: the risk of global warming and calamitous climate change due to our GHG (greenhouse gas) emissions. But there is a second emissions problem as well. Current levels of carbon dioxide in the atmosphere, estimated at 387 parts-per-million (ppm) concentration, could cause extensive losses of tropical coral reefs worldwide.

This is because of ocean acidification due to excess CO2 dissolving in sea water, combined with coral bleaching due to temperature rise. This double-whammy prevents bleached corals from regenerating naturally. Some 20 per cent of coral reefs are already lost, and an equal number are considered seriously at risk.

But does this second problem really matter, beyond spoiling your long-term holiday plan to go diving in the Caribbean or in Asia?

Yes, for two reasons. First, tropical coral reefs are breeding grounds for sea fish, and provide food and livelihoods to an estimated 500 million people