Arctic Bulletin 2022 recently released by the US National Oceanic and Atmospheric Administration (NOAA) includes details that unfortunately are not surprising. Temperatures continue to rise and sea ice is melting. But with these changes comes one that isn’t so obvious: an increase in marine traffic noise, with the potential to affect marine life.
“The increasing number of ships over time in all national and international maritime jurisdictions north of the Arctic Circle raises several questions about relative changes in ship traffic,” said the experts at the Center for Science Diplomacy who wrote the report.
Since 2009, when satellites began tracking Arctic sea lanes, ship traffic has increased as the sea ice barrier has diminished. This was especially true for ships coming from the Pacific Ocean through the Bering Strait to the Beaufort Sea. Experts monitor Arctic shipping for a variety of reasons, including national security concerns and evolving geopolitical competition over the economic benefits of maritime access.
There are arguments as to why Arctic shipping could offer carbon emissions benefits by reducing the length of shipping lanes. But ship collisions and underwater noise affect marine mammals and birds, with the potential to disrupt delicate ecosystems that are already facing the pressure of climate change.
Why noise affects marine mammals
Dr. Kate Stafford of the Marine Mammal Institute at Oregon State University is an expert on how navigation can affect the underwater biophony, or soundscape, of the Arctic and transform it into anthropophony, the human-introduced sound ecosystem.
“Marine fauna, including marine mammals, rely more on sound than any other sense for navigation, foraging, reproductive displays and communication over relatively long distances,” explains Stafford in an article. 2021 article 🇧🇷 “In recent years, acoustic data have documented changes in the seasonal distribution of Arctic marine mammals.”
The ships themselves are not the only source of disturbing sound. Oil and gas exploration, as well as drilling itself, also affect underwater sound in the Arctic. But low-frequency sound from ships can travel hundreds of kilometers, and some routes saw a 44% increase in traffic (measured between 2013 and 2019). Cargo ships and fishing boats are common, but in 2021, four liquefied natural gas tankers crossed the Northern Sea Route without the need for icebreakers.
How this affects marine life is not fully known, although research shows interference with communication and navigation signals and increased stress. It also depends on accurate sound: low-frequency noise is a bigger problem for bowhead whales, while mid-frequency sound has a bigger impact on walruses and ice seals.
“As extensive commercial navigation in the Arctic is a relatively new phenomenon, Arctic species may have a lower tolerance and react more strongly to this noise,” Stafford said, citing data from the Arctic Marine Environment Protection (PAME) group. of the Arctic Council. 🇧🇷
Navigation in the Arctic doesn’t just affect marine life
Indigenous communities living on Arctic islands and coasts depend on marine ecosystems for their lives and livelihoods, and are the most vulnerable to increased maritime traffic facilitated by melting ice.
NOAA’s bulletin calls for better understanding these impacts on “a continuum of urgency” to build resilience as the Arctic environment changes.
By Lauren Fagan. Article in English