Sunday, November 7, 1999

Rock of ages: Cape Roberts project probes Earth’s past

Published in the Antarctic Sun

It’s almost the year 2000, but in McMurdo Station’s Crary Lab it’s closer to 40 million years ago. The Cape Roberts project, in its third year of research, is still in search of layers of rock laid down during the Eocene Epoch, 35-55 million years ago.

Cape Roberts is about climate change. Right now, climate pattern forecasts are made with only a few centuries of data. Cape Roberts researchers hope to add many million years to the known body of climate data.

But this is not Mac Weather’s afternoon forecast. Knowing how climatic trends have evolved over massively long periods of time can help predict what the climate will be like in coming centuries.

In this search back in time, they are looking at material drilled from beneath the sea floor. This seabed core was drilled to a depth of 1968 feet on Friday.

The drill site is at Cape Roberts, about 75 miles northeast of McMurdo, just south of Granite Harbor, in the southwest Ross Sea.

It’s a huge team effort, involving over 60 people, including researchers, technicians, and drillers, among others. They’re all looking at what they know about the earth’s structure and applying
it to the question of climate. At the same time, they’re taking advantage of this rare opportunity to look back in time to further their own studies.

The daily schedule in Crary is a mix of routine and adventure. They begin each day by doing a basic classification of the core which arrives late each night from the drill site. In the middle of the morning they report to each other on research progress.

“With a project like this, with so many specialists, you have to keep informing each other,” said project coordinator Peter Webb.

Each of the scientists working on the Cape Roberts project is a prominent scientist back
home. Here, though, they’re in among a whole group of high-power researchers. But they
share time and space well, and are good-natured about their interactions.

After lunch, the specialists look at the core which was explained in the morning.

They plant small toothpick flags at areas where they want samples taken. In total, the samples
number in the hundreds each day, according to Matt Curren, one of the core curators who
extracts the samples.

Each sample is taken for further analysis. Paleontologists look for fossils in their samples; scientists studying the magnetic field of the earth look at the alignment of particles in their samples; sedimentologists and stratigraphers look at the layering in the sediments.

When the samples have been analyzed, the scientists come back together to discuss what they’ve found.

They compare different types of evidence relating to the age of the core material. The evidence varies widely. Some of it—sedimentary and fossilized— shows what the climate was like, which
the scientists then match up with similar climate sequences from the rest of the world.

“We know what the climate was like in other parts of the world 30-40 million years ago,” Webb said. “The purpose of this project is to try to understand present climate and future climate by looking at the past.”

Antarctica is a special place for doing this type of work because it was the heart of Gondwanaland, the supercontinent from which all landmasses on earth eventually broke off and slowly moved to their current locations.

The scientists also look at the changes in the earth’s magnetic field. They already know the history of shifts in direction and polarity of the earth’s magnetic field. By finding out what the
magnetic field pattern is within the Cape Roberts core, they can match up core sections with periods of time.

After all this work, they learn what the climate was like millions of years ago. But, just as in high school, no science project is complete without a written report. Formal academic science publication can take a long time, sometimes even years. Submission to journals, review, and then actual publication are all both bottlenecks and opportunities for verification of results.

Not so with Cape Roberts. They’ve solved the problem of publication delay by bringing their own
publication to the Ice. Terra Antartica (sic) is an Italian earth science journal which publishes the results of the Cape Roberts Project team. An editor and a graphic artist for the journal are here at McMurdo working full-time to prepare the scientists’ work for release to the wider community of world climatologists.

Before leaving the Ice in mid-December, each researcher must complete an initial report, describing their work on the core and preliminary results. Within 6 months they put out a
final science report, which is also published in Terra Antartica. Less than a year after they begin a season of drilling, the results of research and examination are available to the science world.

What these results reveal is of great import to determining climate change trends.

“The cores are really a proxy for the climate, plants, and topography,” Webb said. Sea level,
average temperatures, plant and animal life, and other information are contained in the core, a cylinder of rock just a few inches thick.

The Cape Roberts Project is a multinational collaboration, in which the U.S., New Zealand, and Italy are the major shareholders (and major funding sources). Also participating are Australia, Germany, and the United Kingdom. The project is going well, in its third and final year of drilling.

“Cape Roberts is successful,” said Italian researcher Marco Taviani, speaking of the time and energy spent, as well as the money and international collaboration efforts.

The project expects to wrap up work and leave the Ice in mid-December. In the meantime, though, they’re hard at work inspecting, marking, analyzing, and collaboration. The phrase Webb sometimes ends meetings with seems to run their lives: “Okay, let’s go look at some more core.”

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