PASSCAL Instrument Center Deploying Greenland Network

SOCORRO, N.M. Sept. 17, 2009 – New Mexico Tech will play a crucial role in a new project to install and operate a vast network of seismic sensing stations in Greenland.

Kent Anderson, a Tech graduate student and IRIS employee, with a seismic sensing station in Greenland. Photo by Guy Tytgat/New Mexico Tech

The IRIS PASSCAL Instrument Center at New Mexico Tech will design, program and install 25 state-of-the-art seismic stations as part of a new ambitious ice sheet monitoring project. IRIS is the Incorporated Research Institutions for Seismology, a consortium that supports collaborative research and facilities and supports the Instrument Center. PASSCAL is the Program for Array Seismic Studies of the Continental Lithosphere, an IRIS Program devoted to supporting portable seismic instruments and data collection throughout the world via the PASSCAL Instrument Center at New Mexico Tech.

The $1.9 million Greenland Ice Sheet Monitoring Network, or GLISN, project, funded by the National Science Foundation, will include deployment and data collection from 25 seismometers on and around Greenland.

“This is by far the most ambitious seismological instrumentation of Greenland ever done at this scale,” Dr. Rick Aster said. “This project will generate a whole new suite of data for scientists to interpret related to Greenland’s geological, glacier, and climate system.”

Aster is the principal investigator for the PASSCAL Instrument Center and the chair of the Earth and Environmental Science Department at New Mexico Tech. He said Greenland is important glaciologically because it contains about 10 percent of Earth’s ice and contributes more sea-level raising ice to the oceans than all other sources in the northern hemisphere put together.

“It’s a big fish,” Aster said. “These glacial events – calving, movements of the ice sheet and water moving underneath – they all have seismic signatures, and we can study them with seismology. If you want to understand a system like the Greenland icecap you have to see how it is changing.”

 Guy Tytgat, polar project senior engineer, with a solar-powered seismic station in Greenland. Photo by Kent Anderson/New Mexico Tech

The seismic network will help monitor Greenland’s icecap and glaciers, how they evolve and how the ice sheet responds to global climate change. The seismological community has a basic understanding of the underlying geology of Greenland, but the new project will also provide much better data on how geological processes, such as the loss of heat from the deep Earth, affect the icecap and its stability with time. Besides the underlying geological and geophysical processes affecting the Greenland Ice Sheet, the data will also advance studies on interactions between oceans, climate and the glaciers and other multidisciplinary areas of interest to climate change studies.

The staff of the New Mexico Tech PASSCAL Instrument Center has already scouted locations in Greenland and is developing sensors that are capable of withstanding the Greenland climate. Aster said the Instrument Center staff has ample experience designing seismic stations currently deployed in Antarctica and other very harsh environments.

Polar projects senior engineer Guy Tytgat of New Mexico Tech will be in charge of preparing the seismic stations, and the logistics and installation at several of the sites. He scouted locations in Greenland in August and is confident that the project will be successful. He said the instruments will be assembled and prepared for installation over the next six months, with deployment scheduled for June 2010.

Tytgat said the project presents quite a few technical and logistical challenges related to extreme climate and remote locations. He and his fellow engineers are drawing on their experience working in Antarctica to develop the Greenland project.

An aerial view of the Greenland Ice Sheet and glaciers flowing off the plateau into a valley. Photo by Guy Tytgat/New Mexico Tech

“Any time you deal with polar regions, it’s very challenging,” Tytgat said. “In Antarctica, there are basically two types of sites: the ones that are cold and the ones that are really, really, really cold.”

While Greenland is warmer than Antarctica, frigid weather is still a concern for seismic equipment and batteries during the winter. The batteries and recording equipment will be ultra-insulated in a high-tech enclosure. All stations will use solar power, but during winter the stations are shrouded in darkness for up to three months at the northernmost latitudes.

“One of the challenges is keeping the equipment running in very cold temperatures,” Tytgat said. “A second challenge is having batteries that produce power at those temperatures. If those batteries fail, we’re dead in the water.” 

In Antarctica, this has meant designing battery systems that operate at temperatures below -100 degrees Fahrenheit.

Tytgat and Kent Anderson, a New Mexico Tech doctoral student and IRIS employee, will, when possible, select coastal locations that are close to settlements so they can tap into electricity and telecommunications. However, the stations can’t be so close that human, or “cultural,” seismic noise overpowers the faint, natural signals that the scientists are tracking.

“It’s always a dilemma finding a ‘quiet’ spot but not too far from a community,” Tytgat said.

IRIS and New Mexico Tech will spend three years in the initial development of the Greenland network. The project is a coordinated international collaboration of eight nations – Denmark, Canada, Germany, Italy, Japan, Norway, Switzerland and the United States.
Data from the Network will be freely and openly available to anyone in real-time, without restriction, Aster said.

– NMT –

By Thomas Guengerich/New Mexico Tech