Most potential effects of climate change – considerable changes in air and sea temperature, sea level rise, increased flooding and desertification, and so on – are now so well established that the topic has recently been turned into a major summer blockbuster. That was Hollywood of course, which the Webster’s American Dictionary defines as ‘exaggeration with intent to thrill’. Yet, global warming is certainly real, and considerable research is being carried out to try and better grasp its likely consequences. That research has turned up some interesting results, published in Science last month.
Global warming and coral reefs: like pinstripe pants and a plaid shirt
The main greenhouse gas is of course carbon dioxide, or CO2. Like rainforests on land, the oceans are an enormous ‘sink’ for the gas. Nearly half of the extra CO2 produced since the Industrial Revolution has ended up in the sea. For those of us on land, that’s great news, right? In some ways yes, as the oceans are acting as a buffer to the effects of global warming. In reality though, that’s long term, as in thousands-of-years long term. For sea creatures it may be quite the opposite. By the end of next century, rising levels of CO2 in the atmosphere may halve the rate at which organisms such as corals, plankton and shellfish (bivalve mollusks) grow. This happens because increased CO2 levels in the sea make it more acidic, dissolving the calcium carbonate that the creatures use to make their skeletons and shells. This problem impacts the ecosystem immediately, and will only get worse over time. The effects of these changes on the wider ecosystem are unknown, but are likely to be significant because these organisms make up the foundation of the marine food web or provide shelter and protection for countless other species.
Is no place safe?
If I’d have seen a chance to bet on the deep sea being the only place on the planet that would not be affected by global warming, I’d have put half my monthly salary on it. Thankfully I saw no such bet, and as a result am now 6 cents better off. Changes in the atmosphere do affect the deep sea. Scientists have found that the prevalence of sea cucumbers – close relatives of starfish and sea urchins – at 13,000 feet off California varies depending on how much food is falling through the waters above. And these rainfalls of food depend on atmospheric climate events like El Nino and global warming.