Rising temperatures can turn ‘carbon sinks’ into ‘carbon faucets,’ leading to a ‘hothouse’ world.
As humans put increasingly large amounts of carbon dioxide into the atmosphere, the planet grows increasingly hotter. To fix this, the vast majority of the world’s governments have agreed to reduce or eliminate their CO2 outputs to prevent the global average temperature from increasing more than a few degrees. But according to new research, our own emissions might not be all we have to worry about.
The Earth is a very complex system, and changing one thing can have repercussions a continent away. In addition, small changes can have extreme impacts that are difficult to predict. A group of researchers has discovered that a number of regions on Earth’s surface could end up releasing greenhouse gases in the future, leading to a ‘hothouse’ Earth that’s several degrees warmer than the present day.
The research, published yesterday in the Proceedings of the National Academy of Sciences, outlines a number of scenarios where a small amount of heating could lead to additional warming events. It is not exactly clear how much of a temperature increase would be required to trigger these scenarios, but the researchers hypothesize as little as two degrees warmer could be enough.
The study examined ten of the Earth’s more vulnerable habitats, including the Amazon rainforest, polar ice caps, boreal forest, and the ocean floor. These regions play a vital role in collecting and trapping carbon dioxide from the atmosphere. In scientific parlance, they’re called ‘carbon sinks.’ However, the researchers found that increasing temperatures in these regions, even a little bit, could potentially turn these carbon sinks into carbon faucets.
Rising temperatures can trigger massive die-offs in places filled with life, for example, such as the oceans or tropical and boreal forests. When plant and animal life in these regions decomposes, it releases stored CO2 into the atmosphere.
In the Arctic and Antarctic, warming can lead to the melting of permafrost, releasing carbon dioxide that has been frozen for millennia. Warming also leads to shrinking snow and ice cover, which means less sunlight is reflected back into space, accelerating warming trends even further.
The important thing to take realize is that increasing temperatures could trigger changes that lead to even warmer temperatures, creating a worrisome feedback loop. “These tipping elements can potentially act like a row of dominoes,” says study author Johan Rockström. “Once one is pushed over, it pushes Earth towards another. It may be very difficult or impossible to stop the whole row of dominoes from tumbling over.”
The end result isn’t necessarily a runaway greenhouse effect, but something called ‘hothouse Earth,’ where temperatures stabilize almost ten degrees Fahrenheit warmer than they are now. This could lead to more than 150 feet of sea level rise in the long run, with increased natural disasters, droughts, floods and everything else that comes with climate change.
The worst part is that even if we cut back drastically on carbon emissions to meet international goals, these natural releases of additional CO2 could occur. Even a little warming, like the kind we’ve already seen, might be enough to kick the planet into this ‘hothouse’ state.
Previously published by: Popular Mechanics USA