Bitcoin is a currency that doesn't rely on cash, but it does use electricity. That could spell disaster.
That's according to a team of scientists from the University of Hawaii, who found that the software-based form of money uses so much electricity it could push global temperatures up by 2 degrees Celsius before the year 2048 if it grows in popularity. The scientists published their research in a paper in Nature on Monday.
It's the most recent piece of analysis to assert that bitcoin is bad for the environment. Mother Jones wrote in December that one bitcoin transaction consumes as much electricity as a household does for a whole week. Environmental publication Grist wrote last year that "bitcoin is slowing the effort to achieve a rapid transition away from fossil fuels."
It's also not the first cryptocurrency accused of causing problems with the sheer amount of processing power -- and thus electricity -- required to use it. Hackers often use malicious software to trick unsuspecting internet users into mining the cryptocurrency Monero on their computers, sometimes causing other programs to grind to a halt and the computer's fan to kick into lift-off mode.
Here's why bitcoin creates carbon emissions. Computers create new bitcoins by running software that taxes processors and draws large amounts of electricity. Each transaction carried out with bitcoin also draws electricity. The amount of electricity each bitcoin transaction uses is especially large considering the small proportion of cryptocurrency transactions that are made with bitcoin, the scientists wrote.
"The environmental concern regarding bitcoin usage arises from the large carbon footprint for such a small share of global cashless transactions, and the potential for it to be more broadly used under current technologies," the researchers, an interdisciplinary team of scientists from the University of Hawaii, wrote in their paper.
Right now bitcoin emissions aren't bringing the apocalypse, but the real problem would be if bitcoin became even more popular, the researchers wrote.
"[O]ur analysis suggests that if its rate of adoption follows broadly used technologies, it could create an electricity demand capable of producing enough emissions to exceed 2 degrees Celsius of global warming in just a few decades," the study's authors wrote.
A rise in temperature of 2 degrees Celsius is important because that's the threshold at which scientists expect climate change to cause devastating and irreversible effects on the planet.
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