Melting water from Antarctic glaciers is changing the composition of the oceans in the region more than was previously known, a new study shows. The measurements that made these findings possible were collected by an unusual group of researchers: seals.
The study, published Friday in Communications: Earth and Environment, uses water temperature and salinity measurements to show how glacial meltwater changes the composition of the ocean near the Pine Island Glacier. one of the fastest retreating glaciers on the continent. The researchers found that the warmer, fresh meltwater was distributed in patches through the ocean, including sections rising near the surface. Those surface layers bring iron and other nutrients to the top of the ocean, which encourages algae and other biomass to grow, as well as keeping the ocean relatively ice-free.
“In this part of the sea the glaciers are melting so fast that they call it ‘Doomsday Glaciers, ” Said Yixi Zheng, lead author of the study and a postgraduate researcher at the University of East Anglia. “We really care about what happens in the region. We want to know how fast it melts and what the impact of the glaciers is on the climate system. ”
While the meltwater of glaciers can best be measured in winter, it is always a problem for scientists if its hydrographic signature is most obvious. Pine Island Glacier is not only extremely remote, but the ocean near the glacier is covered by ice ten months of the year, making access to deeper parts of the ocean with human instruments nearly impossible.
G / O Media can get a commission
Seals can and do swim under sea ice. Zheng and her team use a data set collected by seals swimming near the Pine Island Glacier, which is equipped with sensors that collect water temperature, salinity and pressure. The stamps were then monitored between July and September 2014.
“The seals, they’re so wonderful,” Zheng said. ‘They are very good at finding small holes in the sea ice. Sometimes I feel like we need to give them PhDs. They are doing better than many scientists. ”
As versatile as seals can be, they are not perfect researchers. You can not control where a seal goes swimming, so you can not ask them to patrol a specific area. This makes them somewhat fickle collaborators, but the team was happy with those they had.
“We were very happy in this region. “Right in front of the glacier we hung this seal, with a winter holiday,” said Zheng. It is not so surprising that a seal would decide to set up a shop near a melting glacier: as Zheng’s study shows, the meltwater at the surface of the ocean near glaciers encourages algae, providing more food for seals means.
Researchers have also used seals in other studies. Some of Antarctica’s most charismatic mammals also helped solve a massive hole to form in the region’s sea ice. Scientists have also stamps are monitored from space as a proxy for how healthy different Antarctic ecosystems are. These ecosystems support important fisheries that humans rely on, and what is happening to the continent’s massive ice stocks is affecting coastal populations around the world. In a region that change quickly, can gather any additional data researchers so they can know what’s going on, it’s essential to plan for the next.
Zheng, who tagged seals himself during a trip to Antarctica in 2019, said she sees many opportunities for seals to help scientists collect measurements, and thinks data from seal marks will become more popular in future studies. According to Zheng, the sensors mounted on stamps cost between about $ 4,000 and up to almost $ 7,000. It may seem expensive, but it’s astronomically cheaper than camping a team of scientists with expensive equipment to Antarctica to collect similar data.
“We are very fond of data on stamp marks, and we try to make the best use of it,” Zheng said.