Over the past several decades, scientists have observed a significant increase in the melting of glacial land ice on the island of Greenland, spurring concerns about global sea level rise and the long-term effects of atmospheric warming. What has been less clear, however, is what happens to this meltwater once it enters the ocean.
Now, a team of researchers led by faculty at the University of Georgia has discovered the fate of much of the freshwater that pours into the surrounding oceans as the Greenland ice sheet melts every summer. They published their findings today in the journal Nature Geoscience.
"Understanding the fate of meltwater is important, because research has shown that it can carry a variety of nutrients, which may impact biological production in the ocean," said study co-author Renato Castelao, an associate professor of marine sciences in UGA's Franklin College of Arts and Sciences. "There is also evidence that large freshwater inputs could alter ocean currents and affect the normal formation of sea ice."
The researchers created a simulation that tracks meltwater runoff under a variety of atmospheric conditions, and they were surprised to discover that most of the meltwater found off the west coast of Greenland actually originated from ice on the east coast.
"Meltwater from Greenland is directed by the surrounding ocean currents, but its fate depends on when and where the runoff occurs and the wind fields driving ocean currents," said study co-author Thomas Mote, Distinguished Research Professor of Geography at UGA.
According to the model, wind and ocean currents often transport meltwater around the southern tip of Greenland on a westward journey that can take upward of 60 days. After rounding the tip, the meltwater is largely deposited into the Labrador Sea, an arm of the Atlantic between Canada's Labrador Peninsula and the east coast of Greenland.
Meltwater originating from the west coast of Greenland, on the other hand, is often kept pinned to the coastline by strong winds, which push it northward toward Baffin Bay.
This isn't always how meltwater from the Greenland ice sheet disperses, as shifts in the prevailing winds can produce very different effects. But scientists must be aware of these shifts in order to fully understand how meltwater will affect the environment, Castelao said.
"The meltwater that comes from the east coast could have different qualities from the meltwater on the west coast, including different nutrient compositions," he said. "We need to take the origins of this meltwater into account when we study the effects of ice sheet melt, as it could impact the oceans differently depending on where it comes from."
And this is a problem that is only going to get worse, said Castelao, citing scientific models that suggest the amount of meltwater runoff from Greenland could more than double before the end of this century.
"We need to pay careful attention to where melt and runoff is occurring and how it interacts with surrounding ocean currents, in addition to measuring the total amount of melt," said Mote.
Other researchers working on this project include Hao Luo and Patricia Yager from UGA's department of marine sciences; Asa Rennermalm, Rutgers University; Marco Tedesco, Columbia University; and Annalisa Bracco, Georgia Institute of Technology.
Their study, "Oceanic transport of surface meltwater from the southern Greenland ice sheet," is available at http://www.
Stephanie Schupska | EurekAlert!
Six-decade-old space mystery solved with shoebox-sized satellite called a CubeSat
15.12.2017 | National Science Foundation
NSF-funded researchers find that ice sheet is dynamic and has repeatedly grown and shrunk
15.12.2017 | National Science Foundation
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences