Greenland’s ice sheet, a massive reservoir of roughly 8 percent of the planet’s freshwater, is losing ice at an accelerating pace. From fall 2023 to fall 2024, the island lost 55 gigatons of ice and snow the 28th consecutive year of net ice loss, according to the National Oceanic and Atmospheric Administration (NOAA). Since 1992, scientists estimate, Greenland has lost over 5 trillion tons of ice a mind-boggling amount that drives home the need to better understand this key system.
For the first time scientists have used a custom-built drone to take detailed measure ments of water vapor high above Greenland’s ice sheet. This new approach is addressing uncertainties in our understanding of the Arctic water cycle, with significant implications for projections of ice loss and sea level rise. This is a big deal, said the lead for this project Kevin Rozmiarek, a doctoral student at the Institute of Arctic and Alpine Research (INSTAAR) at CU Boulder: “We will be able to understand how water moves in and out of Greenland in the next few years”.
The research team flew the drone 104 times during the summer of 2022 from a base in East Greenland, the East Greenland Ice-Core Project (EastGRIP) camp, operated by the University of Copenhagen. Our drone-carry on air sampling instruments took us to almost 5,000 feet above the ice sheet, analyzing on the isotopic content of water vapor. Isotopes the kind of variations that exist in hydrogen and oxygen atoms work as “fingerprints,” tracking the sources and changes of water molecules. “Isotopes are water’s fingerprints. By following these fingerprints, we can trace back to the source where the water vapor came from”.
The results showed a more complex water cycle than scientists had realized. Sublimation the process by which snow and ice goes straight to water vapor without first melting is a major contributor to Greenland’s ice loss. Previous research indicated that as much as 30% of summer surface snow in some areas sublimates into water vapor. But where that vapor ends up if and where it recondenses as snow, if and when it returns to the surface, or if it leaves the Greenland water system altogether is uncertain.
With isotopic data captured by the drone, researchers could compare their observations to available climate models. They found that these models had low-balled the amount of precipitation hitting Greenland. Incorporating the new isotopic data, the team fine-tuned predictions of moisture transport and precipitation patterns across those areas. Rozmiarek noted the importance of this breakthrough, “We demonstrated how useful water vapor isotope data is by successfully improving an existing model”.
The ramifications of these findings reach far beyond Greenland. Meltwater from the ice sheet causes sea levels to rise, upends ocean circulation, and influences ecosystems all over the world. Historical data reveals that around 125,000 years ago, in a warm period, Greenland’s ice sheet was much smaller and world sea levels were perhaps 19 feet higher than today’s. With the planet warming more quickly than ever, scientists say that Greenland’s ice sheet could shrink to its size during that period and set off profound alterations to climate systems around the world.
Collecting air samples in the Arctic has long been a costly and technically complicated undertaking that has often depended on crewed aircraft flying through harsh conditions. The use of drones marks an exciting new direction in Arctic research, enabling researchers to gather high-resolution data in a safer and more efficient way. This study set the stage for future studies. Rozmiarek said that understanding, however, filled him with hope “There’s still so much we don’t know. We will be able to understand how water moves in and out of Greenland in the next few years”.
This study highlights the need for technological innovation in the exploration of climate y2013; climate change is strongly influenced by those interactions. And scientists are revealing clues that could alter the way we model and prepare for the consequences of future climate change, by tracking the invisible fingerprints of water vapor. Every new insight counts because the Arctic is heating faster than any other place on Earth.
