Science Magazine just published a peer-reviewed article with some scary findings. The southern ocean has slowed its natural process of carbon absorption. The reason: climate change and ozone depletion. The breakdown in efficiency of these sinks was a expected, but not for another 40 years.
Because of feed-back mechanisms, the decline of Antarctica’s Southern Ocean carbon sink means that atmospheric CO2 levels may be higher in future than predicted.
Oceans are vital as they absorpt excess CO2 from the atmosphere, slowing down climate change. But they cannot keep up the pace of our greenhouse emissions. The rate of absorption has stayed the same for the past 24 years, while global emissions have increased in 40% during that time.
The oceans have had it – maybe we should stop thinking of stuffing our biosphere and oceans with carbon sinks and actually start reducing emissions
This is really scary news!
The world’s oceans are one of two main carbon ‘sinks’ – absorbers of carbon dioxide from the atmosphere, that in the natural carbon cycle help keep greenhouse gas levels in the atmosphere in check. As we destabilize the natural carbon cycle with man-made greenhouse gas emissions, we cause global warming which in turn is expected to weaken the ability of the oceans to absorb carbon dioxide, leading to a further buildup of atmospheric carbon dioxide levels, driving further warming. This is just one of many powerful feedback mechanisms that could push climate change beyond our ability to halt.
Climate models and the IPCC reports take this feedback into account, but generally do not assume it will kick in until mid-century. If the ability of the world’s oceans to absorb carbon dioxide is already beginning to decrease, we will need to recalculate the speed and severity at which the world must cut greenhouse gas emissions in order to stabilize the climate and avoid disastrous climate change.
It’s definitely time to get serious about cutting greenhouse gas emissions as hard and as fast as possible. And the United States needs to lead the way. We need to begin a bold plan to cut emissions as quickly as possible by the end of the next decade, perhaps by 30-60 percent, levels even greater than the supposedly ‘gold standard’ Sanders-Boxer Global Warming Pollution Reduction Act proposes (it calls for about a 15% cut by 2020).
When we read news like this, it’s clear that time is definitely running out!