Glacier technology feels the heat

By Zoe Kleinman
Technology Reporter, BBC News

The probes can lay dormant under the ice for years.

Tools used to monitor glaciers could play a vital role in predicting landslides, scientists have said.

The fist-sized sensors, developed at the University of Southampton, will be used to monitor erosion rates during California's storm season.

The electronic sensors will be placed in Los Laureles Canyon in Mexico.

If they reveal certain changes precede an erosion, it could be the start of an early warning system.

Sudden landslides, particularly common in India and Asia, cause mass devastation, claiming hundreds of lives and leaving millions homeless.

A total of six sensors will be placed upstream from the Tijuana estuary, which is just over the Mexican border in San Diego.

They will record data about their environment over the next two years, monitoring factors such as temperature and movement.

The probes, developed in the UK, take readings every hour and send updates back via radio signal once every 24 hours.

The project has been funded by the US-based National Oceanic and Atmospheric Administration.

Husband and wife team Dr Kirk Martinez and Professor Jane Hart, part of the Glacsweb group at the University of Southampton, have been using them to track glacier movements since 2003.

Climate change

They found that the ice beneath the Skalafellsjökull glacier, part of the Vatnajökull icecap in Iceland, began to warm in February - the first sign of spring - while the land on top was still in the depths of winter.

The Briksdalsbreen Glacier in 2001...

"In terms of climate change they are a thermometer of what's changing," explained Dr Martinez.

"If they could give us a warning about landslides too, it's worth doing."

The Vatnajökull icecap is currently the largest in Europe.

The scientists witnessed the dramatic nature of climate change first hand when the original glacier they were studying, Briksdalsbreen Glacier in Norway, shrank significantly during the course of their research.

... and in 2007

The new climate for the probes is a steep contrast from their old habitat.

They will be compacted in mud rather than ice and they will not be as deep as they needed to be under the glaciers.

Dr Martinez and Professor Hart are preparing to modify them if necessary, but as each element of the probe is handcrafted, even the smallest of modifications is rarely straightforward.

"They're like Christmas puddings," said Dr Martinez. "They require a lot of work."

Probe power

The probes are powered by lithium thionyl chloride batteries, and have a life expectancy of 10 years.

With the exception of their daily report and hourly measurements, which take one second to complete, they are completely dormant to conserve power.

The sensors will upload their daily data via radio.

"Most researchers put down sensors on a wire, but they tend to snap," said Dr Martinez.

"They are so delicate - you're looking at three kilometres of foam-wrapped cable inside massive moving ice. I did it that way once and thought, I can never do this again."