April is a time of change in the Southern Hemisphere, typically when autumn brings falling leaves and changing weather. Even though there are no falling leaves here at Halley, the changes in weather have been noticeable. It is certainly colder, now frequently below minus 30 degrees Celsius and each day this month has been successively darker.
At the beginning of April we witnessed the aurora australis, an atmospheric phenomenon unique to the poles of the Earth. Auroras are created by charged particles in the sun's solar wind, which follow the Earth's magnetic fields to the poles. The aurora is difficult to capture on film for its sheer magnificence. It was a sheet of luminous green light which seemed to shimmer and flame in the Antarctic night sky. It was cold, about minus 30 degrees as we gazed at the starry sky in awe. Times like this are special at Halley, when we pile outside to see something truly wondrous outside our front doorstep, as it is a reminder of the powerful environment in which we live.
Jamie Keir, our data manager, has prepared a short video clip of an aurora at Halley. This was taken by TULA, an all sky imager (468 KB and you will require a MPEG player).
The skies this month have been particularly impressive. There have been sunsets of red and orange tones. People say that the ice is white but the autumn light has lit it up in stunning colours. It is pink when the sun reflects light low on the horizon. It reflects golden when twilight is in the sky. As night falls, there are deep blue shadows on the surface of the ice which turn to dark black as the moon comes up in place of the sun. The full moon was spectacular as it lit up the sky like a lightbulb. It would still be in the sky by mid morning and disappear as the sun would rise late in the east. The sun did not seem to linger long and would set earlier in the afternoon as each day passed by in April.
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| Autumn colours over the Simpson Building. |
Temperatures of minus thirty brings the kind of cold which feels like it freezes you from outside in. At minus ten the air dries up our nasal passages. Minus twenty is quite bearable. But minus thirty ices up our eyelashes, freezes condensation and sweat on our hats and neckwarmers and forms icicles our our bearded winterers. It is made even colder when strong wind bites, as the wind chill drops the temperatures even more. We all have our favourite items of clothing and items such as facemasks and earwarmers are ideal for windy days. The cold doesn't forgive us if we stand idle for any length of time. Fingers, ears, cheeks and noses are particularly susceptible to frostnip in the bitter wind. After coming into the warmth, the ice melts around our eyelashes and drips down our faces and small puddles of melting snow form around us.
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| Richard Turner, Halley's chef, freezing up in cold temperatures. He is wearing a head and neckwarmer, snow goggles, a neoprene facemask and a ventile jacket. |
Our last field trip went to the Hinge Zone at the beginning of the month. They experienced very cold conditions, camping in minus forty degrees Celsius. Their days out were sunny but countered by bitter wind, such that they stopped only for very short periods. Even the keenest photographers did not stop to take many photos, in order to keep moving to keep the cold at bay.
Some members of base are still skiing on a regular basis. Even though Halley Station sits on the flat Brunt Ice Shelf, there have been mounds of snow forming which provide some variety in the terrain. These windtails have accumulated along the western side of a container line, where our spare equipment is stored, and make for good skiing. Man-hauling is another popular form of exercise and was the historical method of travelling in the days of previous polar explorers. This involves walking in a harness attached to a weighted sledge. The going is difficult when the snow is soft as footsteps sink in the snow, requiring more effort.
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| Richard Turner, returning to Halley Station from a manhauling trip |
It seems a distant memory to wear shorts and a t-shirt outside. Smells of freshly cut grass or flowers also seem far away. The Antarctic air is cold and fresh, but it is the absence of smell that is so distinctive. We are steadily running low on our supplies of fresh vegetables and fruit and news from the outside world arrives daily on two sheets of size A4 paper. Our nearest neighbours are a colony of hundreds of emperor penguins, 30 kilometres away. The male penguins will now be assembling to prepare for the winter ahead, huddled together and keeping their eggs warm.
Our team of sixteen have settled into a routine. Although we have a professional chef, we take turns to cook to give him a day off. We also take a turn at cleaning, night watch and and participating in work off or around the station. Our meteorologists work at specific times to obtain meteorological data but generally we work from 9am to 5pm Monday to Friday, working extra hours when required. This is especially so when outside work is postponed during the week due to poor weather. There are a number of alarms on the buildings, which if triggered, mean more work for some. Richard Borthwick, our Heating and Ventilation Engineer, has had more than his fair share of alarms this month. The boiler broke down, the water pump failed and the melt tank blocked up with snow all in the space of a week. Catriona Gillies, our steel erector, profiles him and two other members of our technical services team, part of the support staff who maintain the station buildings and vehicles.
Our melt tank is a structure which is vital for our existence. Each day, snow is shovelled into a shaft which descends into a series of tunnels 17 metres underground. Here the snow melts, water is filtered and pumped up to the day tank on the main accomodation platform. Every second day, we enlist the assistance of a bulldozer driver, who piles the snow up in mounds around the hole. This way the snow is easier to shovel.
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| Andy Cope, Richard Borthwick and Dave Glynn, shovelling snow into the melt tank hole in 40 knot winds and blowing snow, a daily task required for Halley's water |
The last week of April brought 40 knot winds and gusts to 56 knots. This equates to a wind speed of approximately 62 miles per hour. This can reduce visibility to a few metres and the low light condition renders the contrast poor on the ice. In such white-out conditions, it is not easy to distinguish the level of snowdrift on surface and is easy to fall into holes. Fortunately these holes are not big, as our surrounding area is safe from the danger of deep crevasses. Going out into this degree of wind requires a strong constitution and dressing well for battling against the elements. Daily checks and chores are still required to be carried out and our science continues despite the prevailing conditions.
With the last session of fuelraising this month, we have completed most of the work required to prepare the station for the winter period. Gary Wilson, one of our meteorologists, describes drum raising to N9. This event took seven Halley members off the station.
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| Alex Gaffikin and Neil Farnell, wearing breathing apparatus, as part of monthly fire training at Halley. |
On Easter Sunday, Alex Gaffikin, another of our meteorologists, organised an egg hunt . These eggs had been deemed unfit for human consumption, so they were boiled up, painted and hidden at various points on the Laws building. It took determined efforts to find all of them and on their discovery we were rewarded with a fair share of chocolate. Other members of the station have been exercising their talents. Jamie Keir has been giving computer tutorials, including the use of html, which enables me to produce this diary. Halley's musicians are preparing music to play for a midwinter concert. We held a slide show earlier in the month, which reminded us of what green trees and cities look like.
The sun rose on April 28th, a huge orange disc covered by a fine mist. This was the day of sundown, which is a significant occasion in Antarctica as we will not see the sun again for another four months. We marked the milestone with a barbeque in clear skies and minus 35 degree temperatures. We had to eat quickly to avoid frozen ketchup on our plates and our forks sticking to our mouths. As the sun disappeared below the horizon, Erny Duston, our most senior citizen, ceremoniously lowered the Union Jack flag and gave an inspired speech. We toasted the occasion with champagne and managed to down our tequila sunrise cocktails only just before they set solid in the cold temperatures. The platform of our accomodation building was the venue for the best nightclub in the world, where we played cricket, rugby, ate sirloin steak and danced until the ice turned dark. It was stunning seeing the twilight colours on the horizon, the risen moon and the stars. Then we were treated to a firework display and we went inside only after we were too tired from dancing and it got too cold to stay out; the end to a perfect day.
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| Sundown |
With the departure of the sun, we now look forward to its return in August. Now darkness descends and the sun seems very far away as we see only its remnants with the knowledge that it is just beyond our horizon.
I hope this has conveyed a little of what the changing season has been like for us at Halley Station. We have seen Antarctica personified, in many moods. Some days she exhibits a good temper with fair winds and soft colours in the sky. Other days we feel the force of her fury as she unleashes a raging wind and blows spindrift into our pockets and into our boots. It remains a wondrous world, where we are privileged to be living.
Best wishes to you all,
