Bitcoin could raise global temperatures

Bitcoin is the leader in the world of cryptocurrencies, which have exploded onto the digital scene in the last few years for their anonymity and ease of access. Advocates have pointed towards their potential to solve the global financial crises, aid in issues such as homelessness and human trafficking, and prevent fraud and security risks. But a new study from the University of Hawaii at Manoa published in Nature Climate Change has found that if Bitcoin catches on at the rate of other technologies, it could raise global temperatures by as much as 2°C by 2033.

The research team analyzed the power efficiency and geographic location of the computers mining Bitcoins, determining that Bitcoin mining accounted for 69 million metric tons of carbon dioxide in 2017 alone — approximately the same as the entire state of Arkansas. According to the study, even if Bitcoin is incorporated at the slowest rate past technologies have caught on, it will warm Earth by 2°C in 22 years.

Findings by the Intergovernmental Panel on Climate Change (IPCC) indicate that this rise in temperature could endanger species such as the polar bear and caribou, place 10 million people at risk of coastal flooding, and reduce water availability in some regions by 30 percent.

Cryptocurrencies like Bitcoin rely on a computationally-intensive encryption algorithms. Each transaction requires complex calculations on groups of computers around the world in order to keep a digital record of sales or purchases in what is called a blockchain. So far, Bitcoin mining computers have relied primarily on coal as a cheap source of electricity, with little regard for the environmental consequences.

Randi Rollins, a master’s student at the University of Hawaii and coauthor of the study, said, “Bitcoin is a cryptocurrency with heavy hardware requirements, and this obviously translates into large electricity demands.” Indeed, a study last year found that a single Bitcoin transaction uses enough electricity to power a home for nearly a month.

One way to curb the environmental effects of Bitcoin might be to increase the size of each block on the blockchain record, thereby reducing the amount of computation required for each transaction. However, this would negatively affect speed and efficiency, two main advantages of the cryptocurrency.

“We cannot predict the future of Bitcoin, but if implemented at a rate even close to the slowest pace at which other technologies have been incorporated, it will spell very bad news for climate change and the people and species impacted by it,” said Camilo Mora, associate professor at the University of Hawaii and lead author of the study. He continued, “Right now, there is no reason to be concerned. [But if Bitcoin] continues to grow, it could get out of control pretty fast.”