AON to Observe Arctic Ice for Eons

The National Science Foundation (NSF) has awarded a $926,000 grant to three researchers, who plan to mount carbon dioxide (CO2) and pH sensors on ice floes in the Arctic Ocean, in order to monitor the changes taking place currently as well as to help predict what will happen over the next century.

The grant will support the goals of the NSF’s Arctic Observing Network (AON), which is dedicated to facilitating research in Arctic environmental change.

Until recently, scientists have had limited ability to observe the Arctic. They have been deterred from bringing their instruments to the region—let alone, leaving them there, or retrieving them—by the ice blanketing the ocean, along with the extreme weather conditions.  

Now, they have found a way to transmit continuous, real-time data by satellite about the conditions beneath the ice—and to put the ice to work for them, in the process. They call it the ice-tethered profiler, or ITP.

The grant recipients—led by physical oceanographer John Toole and Arctic research specialist Rick Krishfield of the Woods Hole Oceanographic Institution (WHOI) in Massachusetts, as well as former colleague, Mike DeGrandpre, now an aquatic chemistry researcher at the University of Montana-Missoula—have been working on the ITP for about eight years.

The first ITP was deployed in 2004 in the western Arctic Ocean, north of Alaska. It shut down shortly afterward, a victim of the harsh Arctic environment. Two more were deployed in the same region in 2005 and three more in 2006. Since then, more ITPs have been attached underneath the floes, and the scientists have been working on additional sensors that will measure chlorophyll, particles, solar radiation, and other important ocean properties that provide evidence of changes in the ocean's ecosystem.

Under the NSF grant, two of the collaborators, Tool and Krishfield, will place ten CO2 and pH sensors in six Arctic locations. The CO2 and pH sensors will be customized for deployment in the Arctic by Missoula’s Sunburst Sensors; a company co-owned by DeGrandpre and spawned by his UM research.

 To install an ITP, researchers use an auger to drill a ten-inch-diameter hole in the ice, much the way an ice fisherman would set to work. Anchored to the ice floes, ITPs slowly drift with the natural movement of the Arctic ice pack, measuring seawater properties below. They are designed to last three years—about the same lifespan as the floes that support them. The sensors will transmit information to Woods Hole about the penetration of human-produced CO2 in the Arctic Ocean—which leads to acidification, with fatal consequences for many organisms.

“With global warming, we are seeing less summer sea ice, and the sea surface is warming and freshening,” DeGrandpre said. “This changing physical environment is altering the carbon cycle in the Arctic Ocean.”

WHOI also is working with colleagues from the Cold Regions Research and Engineering Laboratory, the U.S, Naval Postgraduate School, the University of Washington, Oregon State University, the Japan Marine Science and Technology Center; the National Oceanic (News - Alert) and Atmospheric Administration; as well as institutions in France, Germany, Russia, and Canada. The changes that they monitor in the Arctic’s ice, ocean, and atmosphere will likely help the world’s population to track and react to coming climate shifts.