Glaciers contribute to climate change

The response of the world's glaciers to global warming is an important element in understanding climate change, involving sea-level change and changes to the circulation in the North Atlantic. To predict changes, scientists believe it is vital to understand the behaviour of glaciers.

In the first investigation of its kind in the world, Southampton University's interdisciplinary Glacsweb team in southern England is recording glacier behaviour through a network of sensor probes installed directly into the glacier. Their project is aimed at understanding glacier dynamics and climatic change, as well as making advances in "pervasive sensor networks".

The Glacsweb team, led by Dr Jane Hart, Dr Kirk Martinez and Dr Royan Ong, installed a sensor network in 2003 at the Briksdalsbreen glacier in Norway. This glacier advanced dramatically in the 1990s as a result of climate change, and the team will return to Briksdalsbreen this summer to deploy a second type of probe that is based on new research developments.

"The aim of the Glacsweb project is to study climate change through its effects on glaciers," said Dr Martinez of the School of Electronics and Computer Science.

"We are using "subglacial probes' beneath a glacier, communicating to the surface via radio links. They contain various sensors and their position and orientation is sensed by the surface system. This is the first time wireless probes have been put inside glaciers and it involves many challenges. The systems must feed data back to a server in the UK and contend with communication loss, power loss, noise and bad weather."

The probes are installed in the sedimentary base of the glacier, about 60 m under the surface, with the help of a powerful hot-water drill. They record temperature, pressure, speed and movement of the ice and, more importantly, of the sediments at its base.

The probes emit signals carrying the data that are relayed to a base station on the glacier surface by radio communications and then transmitted to Southampton by mobile phone. The data is available to researchers (at: www.Glacsweb.org).

The project is part of the UK government's Next Wave Technologies & Markets program. This aims to ensure that UK business is structured and equipped to exploit new information and communications technologies and products that enable intelligent functionality to be embedded into devices that will eventually become an integral part of life. The Envisense centre at Southampton hosts projects in the areas of larger-scale reconfigurable pervasive computing, such as environmental projects.

"A combination of technologies has made sensor webs possible," added Dr Martinez. "These will eventually be spread around the world and will give us a clearer picture of exactly how we are changing our environment. In order to make successful sensor webs issues such as communications, low power, robustness and adaptability have to be solved through a combination of mechanical engineering, electronics, computer science and environmental science.

"Our sensors are housed in "electronic pebbles' that will behave as part of the glacier, enabling us to get the clearest picture possible of what is happening deep below the surface."