Aasiaat, Greenland — As the Greenland ice sheet continues to melt, an unexpected phenomenon is occurring along the island’s coastline: the land is rising. Over the past four summers, a research team from Columbia University’s Lamont-Doherty Earth Observatory has flown to Aasiaat, a town located on an island in the Aasiaat Archipelago, to study how the shifting sea levels are affecting the region. Their findings reveal a stark contrast to the global trend of rising seas, with local sea levels actually declining as the ice sheet melts.
The town of Aasiaat, roughly 25 miles from the Greenland ice sheet’s edge, has a rich industrial history rooted in aquaculture. Its brightly coloured houses, which date back to the colonial era, stand in striking contrast to the surrounding icy landscape. In the winter, snow blankets the town, while in summer, gray metamorphic rocks emerge along the coast, and fishing boats populate the harbours. The shallow waters around the town are rich in nutrients, supporting a diverse marine ecosystem, which includes plankton, fish, seals, whales, and seabirds.
As the ice sheet melts, the land is experiencing what scientists call isostatic rebound — a process where the Earth’s crust, once compressed by the weight of the ice, is gradually rising. This is a slow but steady upward movement, with the land rising by millimetres each year. While this may seem like good news for residents, the changes in sea levels and the coastline are more complex than they appear.
In addition to the land rising, the melting of the ice sheet has another, less visible consequence. Greenland’s ice exerts a gravitational pull on nearby ocean waters, drawing them towards the island. As the ice sheet melts, this gravitational pull weakens, causing water to redistribute. This redistribution can lead to local sea levels around Greenland falling, while global sea levels rise. This phenomenon is causing a decrease in sea levels along Greenland’s coast, with predictions of a drop of between one and three meters by the year 2100.
The shift in sea levels and the changes in coastal waters present new challenges for the people of Aasiaat and other coastal communities in Greenland. As the water levels decrease and the coastline rises, it will affect everything from local marine life to the infrastructure that the people of Aasiaat depend on for daily life. Shallow areas that were once accessible may become isolated, cutting off vital transport routes used by residents. Some of the local waters may become too shallow for boats to navigate safely, while the water flow necessary to sustain healthy ecosystems may be disrupted.
These changes will also impact marine life, as the redistribution of water may cut off certain areas from the nutrient-rich currents that support fish, seals, and other marine mammals. Young fish, which rely on coastal habitats for growth, may find it harder to survive in the increasingly altered waters. For people in towns like Aasiaat, this means that access to the sea for fishing and transport could become more difficult, potentially threatening their way of life.
To address these challenges, researchers are working closely with the local community. The Lamont-Doherty team is mapping the ocean floor and creating bathymetric data for the region, which will help locals understand how the waters are changing. This data is being incorporated into an app used for navigation and is available in Greenlandic, Danish, and English. By putting the data in the hands of the community, the team hopes to help residents better understand the evolving seascape and adapt to the new realities of their environment.
More Read
Locals have long been aware of the gradual changes in their surroundings. Older residents recall that patches of land that were once submerged are now above the waterline, and some of these areas are now being used for purposes like preparing fish. These observations have prompted residents to reconsider their expectations for the future and to adjust to the changing environment.
As the ice sheet continues to melt and the land rises, the research team is working to ensure that the local community is prepared for the future. The data being collected will be essential for planning new infrastructure, such as docks and transport routes, to accommodate the changing sea levels. By fostering Greenlandic scientific expertise, the team aims to ensure that the rising land and falling sea levels are factored into future planning, helping the community adapt as the environment continues to shift.
While Greenland’s land may be rising, the impact of global climate change is still being felt worldwide. The melting of Greenland’s ice sheet contributes significantly to global sea-level rise, which threatens coastal communities across the globe. The future of the Greenland ice sheet depends on factors such as greenhouse gas emissions, climate actions, and natural variability, but one thing is certain: the landscape of Greenland is changing, and its residents will need to adapt to these new conditions in the years to come.
