MercoPress. South Atlantic News Agency

BAS will shut down Antarctica's Halley VI in winter because of ice shelf crack

Halley VI Research Station is currently being relocated to a new site 23 kilometres ms upstream

British Antarctic Survey (BAS) has decided not to winter at Halley VI Research Station for safety reasons. The station, which is located on the floating Brunt Ice Shelf in Antarctica, will shut down between March and November 2017.

 Changes to the ice, particularly the growth of a new crack, presents a complex glaciological picture that means that BAS scientists are unable to predict with certainty what will happen to the ice shelf during the forthcoming Antarctic winter. As a precautionary measure BAS will remove its people before the Antarctic winter begins.

Halley VI station is in the final stages of being relocated 23 km from its present site to put it upstream of a previously dormant ice chasm that began to show signs of growth in 2012.

In October 2016, a second crack appeared some 17 km to the north of the research station. Since then glaciologists have monitored the growth of this crack using a network of GPS instruments that measure the deformation of the ice, together with European Space Agency satellite imagery, ground penetrating radar, and on-site drone footage, which show that the recent changes to the Brunt Ice Shelf have not been seen before.

They have run computer models and created bathymetric maps to determine whether or not a large iceberg will calve, and the impact that could have on the remaining ice shelf. They conclude that they are unable to predict with certainty what will happen to the ice shelf during the forthcoming Antarctic winter and beyond.

There is no immediate risk to the people currently at the station, or to the station itself. However, there is sufficient uncertainty about what could happen to the ice during the coming Antarctic winter for BAS to change its operational plans. BAS is confident of mounting a fast uplift of personnel during summer months if a fracturing of the ice shelf occurred. However, access to Halley by ship or aircraft is extremely difficult during the winter months of 24-hour darkness, extremely low temperatures and the frozen sea.

The Director of BAS has therefore decided that it is prudent for safety reasons to shut down the station as a precautionary measure and remove its people before the Antarctic winter begins. There are currently 88 people on station including summer-only staff working on the relocation project and 16 who were scheduled to over-winter.

Every effort is currently being made to ensure the continuity of long-term scientific data capture in these circumstances. Options to temporarily redeploy research and technical support teams to other parts of BAS are being explored.

Halley VI Research Station is an internationally important platform for global earth, atmospheric and space weather observation in a climate-sensitive zone. In 2013 the station attained the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW) Global station status, becoming the 29th in the world and 3rd in Antarctica.

Director of Operations Captain Tim Stockings says, “Halley VI Research Station sits on a floating ice shelf. It was designed specifically to move inland if required. The current work to relocate our station is going very well.

This challenging engineering project is scheduled to complete as planned by early March 2017. We want to do the right thing for our people. Bringing them home for winter is a prudent precaution given the changes that our glaciologists have seen in the ice shelf in recent months. Our goal is to winterise the station and leave it ready for re-occupation as soon as possible after the Antarctic winter.”