Melting Arctic Permafrost Releases Acid that Dissolves Rocks
As temperatures rise in the Arctic, permafrost — permanently frozen ground — is defrosting at an alarming rate. But the permafrost isn't the only thing in the Arctic that's melting.
Exposed rock that was once covered in ice is dissolving, eaten away by acid. And the effects of this acid bath could have far-reaching impacts on global climate, according to a new study.
Icy permafrost is rich in minerals, which are released when the ice melts. The minerals then become vulnerable to chemical weathering, or the breakdown of rock through chemical reactions, scientists recently reported. They investigated areas once covered by permafrost in the western Canadian Arctic, finding evidence of weathering caused by sulfuric acid, produced by sulfide minerals that were released when the permafrost melted.
Another type of naturally occurring chemical erosion is caused by carbonic acid, and it also dissolves Arctic rock. But although carbonic-acid weathering locks carbon dioxide (CO2) in place, sulfuric-acid erosion releases CO2 into the atmosphere, and it does so in quantities that were not previously accounted for, researchers wrote in the study.
Hundreds of mummified penguins in Antarctica can tell us a lot about climate change
New research has connected hundreds of mummified penguin carcasses to two disastrous weather events thought to be influenced by climate change.
The study, which was published in the Journal of Geophysical Research – Biogeosciences, warns that these events might foreshadow what's to come if the Earth continues to get hotter.
A team of Chinese and Australian researchers found the mummified Adélie penguins under a remarkably thick layer of sediment in Long Peninsula, East Antarctica, which usually has a dry climate.
Then, using radiocarbon dating, the scientists found that most of the mummified carcasses were from two specific incidents that affected breeding colonies from 750 and 200 years ago.
The two instances of unusually thick sediment were evidence to the researchers that a lot of water flowed over the area in a short amount of time.
Since penguin chicks do not develop waterproof feathers until a later stage of development, a particularly wet or snowy season would put them in danger of getting hypothermia and dying — which is why scientists believe they found the large number of dead chicks in the two breeding colonies.
The weather event they suspect to be the cause is called zonal wave 3 (ZW3), which produces near-shore ice and adds a lot of moisture to the atmosphere.
Research showed that this meteorological pattern became more frequent in the late 20th Century due to an increase in greenhouse gas emissions.
Since the world hasn't done enough to curb our collective greenhouse gas emissions, researchers fear that ZW3's will become more frequent than ever before and penguin populations will continue to face unfavorable conditions that will jeopardize the survival of the populations.
This particular breed of Antarctic penguins have seen a slough of catastrophic breeding seasons recently.
In 2017 all but two penguins from a colony of 40,000 died from starvation. Earlier that year, only two chicks from a colony of 18,000 breeding penguins survived. That same colony lost every chick in 2013.
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