The melting of glaciers and ice sheets in Arctic Greenland is continuing. This meltwater is affecting the ocean and its ecosystems, impacting the lives of people living in these harsh natural environments. Collaborating with local communities is vital for understanding this rapid climate change and subsequent impacts on the natural environment occurring in the Arctic region and society.

Do you know the ice-covered island of Greenland facing the Arctic Ocean? It is located between the North American continent and Europe, on the opposite side of the North Pole from Japan (see Figure 1). The island has an area of about six times that of Japan. 80% of it is covered by ice, averaging 1,700 meters in thickness, constituting the Greenland Ice Sheet, the largest glacier in the Northern Hemisphere. In addition, countless numbers of glaciers also cover the island. The Arctic region is experiencing the fastest warming on Earth, which causes rapid melting of these glaciers and the ice sheet, severely impacting the global environment. Moreover, the changing environment, as indicated by these melting glaciers, is also significantly affecting the lives of people living in Greenland.
When land-based glaciers and ice sheets melt and flow into the sea, the amount of seawater increases, raising sea levels. Half of the global sea-level rise is due to meltwater from glaciers and ice sheets. Greenland’s contribution to this rise is the largest, accounting for 40% of the impact from glaciers on sea levels worldwide. However, changes to the ocean from melting ice are not limited to sea levels. The North Atlantic, where Greenland is located, is a crucial point in the ocean general circulation, where warm water from the equator cools and sinks. If freshwater from melting glaciers dilutes the salinity of seawater, it could hinder it from sinking, potentially halting the Atlantic meridional overturning circulation. If this happens, the supply of warm water from the equatorial region would be disrupted, and the east coast of North America and Europe could experience a rapid cooling.

We have been conducting observations in Qaanaaq Village in northwestern Greenland since 2012 to understand the fluctuations of glaciers and ice sheets and their effects on environments and society. These long-term observations have clarified the the rates and mechanisms of glacier loss. There is no doubt that the rapid rise in temperature in the Arctic, which is said to be happening four times faster than the global average, is the leading cause of glacier melting. However, it has also become clear that rising temperatures are not the only cause. Microorganisms, thriving due to environmental changes, have darkened the ice (Figure 2a). Just as wearing black clothes in summer makes you hotter, the increased absorption of light energy in these dark areas makes the ice melt more quickly. Ocean warming is also impacting the glaciers. In Greenland, those parts of glacier termini that flow into the sea have been found to be melting due to the warmed seawater, causing them to retreat (Figure 2b).
It has also become clear that glaciers and ice sheets, that change as a result of the sea’s impact, play a significant role in the marine ecosystem. When the glacier termini are submerged in the sea, meltwater is discharged from their base into the ocean. This freshwater, which is expelled to the deep sea, then rises up due to the difference in density with the seawater. This brings nutrient-rich seawater, plankton, fish, etc., from the deep sea to the surface (Figure 2c). When the ice melts even more in the summer, many seabirds flock to the front of the glaciers, and seals are also often seen. They gather in search of the food carried by the meltwater, which means the meltwater from the ice supports the marine ecosystem. If the glaciers shrink and retreat from the sea, the environment supporting this marine life will change significantly.
Our research in Qaanaaq Village relies heavily on the support of local people. For example, local fishermen provide boats for our sea observations. Working with them, we realized that the environmental changes we study significantly impact human society. Greenland relies on the blessings of the sea through fishing and hunting. Therefore, changes in the marine ecosystem are of great importance. Rising sea temperatures have recently led to unfamiliar fish and shellfish being caught. The period of sea ice covering the ocean has also decreased, making traditional hunting with dog sleds difficult while increasing opportunities to use boats for transportation. The melting glaciers are also having a significant impact on society. We have seen roads and bridges in Qaanaaq Village destroyed by the increased water flow from rivers fed by glacial melt many times. In the summer, when temperatures rise, floods have occurred due to the large amounts of meltwater. However, larger-scale disasters are also being caused by flooding from heavy rains. Similar to Japan, heavy rains are increasing in the Arctic to previously unseen levels. Landslides caused by heavy rains on steep slopes have also affected settlements.

Our research began with glaciers, but the study area of the project hasextended from the glaciers to marine ecosystems and human society. In addition to marine ecosystems and terrestrial fields, we are also collaborating with social science researchers to broadly investigate the natural environmental changes caused by climate change and their social impacts. We believe that sharing our research findings with the people of Qaanaaq Village could contribute to a sustainable future of Greenland. Thus, we began holding workshops with the villagers in 2016 (Figure 2d). We introduce our research projects and findings, and the participating villagers share their observations and knowledges of local environmental changes. People living in harsh environments are sensitive to changes in climate and have keen observational skills. The workshop discussions clarify problems in our research and help reveal directions for future topics.
Dialogue with inhabitants is vitally important for advancing research in the Arctic. Although the changes in the Arctic have global impacts, research cannot progress without understanding from local people. There is also a need for sharing the findings and data revealed through research to contribute to the future of these areas. As a next step, there is a call to consult with locals in determining research topics and to propose projects together. However, these kinds of initiatives will not materialize overnight. With our research activities in Qaanaaq Village now continuing for over a decade, we hope to work with the community in designing research projects that meet local needs and make efforts together to realize them.