The Voyage Home - Mawson to Hobart.

Dusk.

Conditions for the first few days sailing where overcast with slight seas. After our detour to the algal bloom area where water samples were taken and krill collected, Scott the master of the AA steered an easterly course. This provided more viewing of icebergs however the dull conditions were not good for photographs. The easterly course had us pass north of Davis station and also close to Casey station before heading NE toward Hobart.

Antarctic Petrel

Giant Petrel

Giant Petrels on pancake ice

For the first week birds including Giant, Antarctic, Wilson’s Storm, Cape, and Snow Petrels followed the ship. Others appeared as we went further north including Black Brow and Light Mantled Sooty Albatross and Shearwaters, Crab Eater, Leopard and Weddell seals on ice floes and breaching Fin, Pilot and Humpback whales were also common. But as we moved further north the occasional wandering albatross was all that was seen.

Cape Petrel

Light Mantled Albatross

Wandering Albatross

Black Brow Albatross

Humpback Whales

Humpback Whales

 

Killer Whale

Two emergency musters drills were held on board the ship. The first on the morning after departing Mawson while snow lay on the ships decks and the second on the morning of the 10th March. The muster exercises the emergency evacuation procedures.

Voyage 4 track.

The route once set to the NE passed between low pressure systems in the 50 and 40 latitudes. The better sailing conditions maximised the comfort of passengers as we had mostly following wind and swell. Only for one 24 hour period were conditions moderately rough with 5-6 metre following seas with a side on component. The ships speed was fairly constant at around 15 knots slowing during hours of darkness where ice was present in the early stages of the voyage.

Calling bids for a can of beer!

Knot Board

Haka.

A special night was held on Friday the 9th March - a pizza night, followed by a charity auction for Camp Quality, the ship's charity of choice. Many items were donated for the auction by those on board. The Boson made a number of rope items including a rope knot board, woven rope mats and other nautical rope items, each attracting strong bids. The ships dining room offered up an a la carte 3 course romantic dinner for two with background live music and a meal for one with the ships master in uniform at the Captains table. Top of the list were 4 weeks accommodation in France close to Champagny in the French Alps and a weekend for two at the ANARE Ski club’s lodge at Mt Baw Baw, Victoria. Two Kiwis performed the Haka for a small price to finish off the bidding. By the end of the night just under $10000 had been raised. A trivia night was held on another evening after dinner.

Romantic dinner for two.

The voyage speed was maintained at about 15 knots it became apparent that the arrival time would be earlier than expected. About 4 days out we were advised that at current speed the ship would arrive during the afternoon of Thursday 15th March. We were also advised that the early arrival time would allow the ship to be bunkered (refuelled) at Self Point wharf and therefore a day saved on departure for the turnaround Voyage 5 to Davis station. The only catch was that disembarkation at Self Wharf (a fuel terminal) would mean being bussed to Macquarie 2 Wharf to meet loved ones. The earlier arrival time would also disrupt planned schedules of loved ones coming to Hobart to meet the ship.

As Thursday 15th March dawned, the rugged south east coast of Tasmania rose close to our Port side. As we rounded the southern tip of Tasmania and made our way up the Derwent estuary the smell of eucalyptus leaves and smoke was striking. The hazy air and higher humidity with warmer conditions was also noticeable. It wasn't long until the mobile phones, dormant for a year, were suddenly activated by incoming text messages. That was a signal that civilisation was again in range and phone calls were made thick and fast.

The Pilot arrives

At one point the ship was accompanied by a pod of dolphins surfing the bow wave. As Hobart came into view, the presence of a tourist ship dominated the city skyline. The pilot boat came out to meet the AA and by 10.30 the pilot was on board. He guided the ship under the Tasman bridge and just after 11:00 we tied up at Selfs Point.  

Passing under Tasman Bridge

Selfs Point

Our last lunch was taken on board while customs and Quarantine staff processed passports and entry documentation.





At around midday we disembarked down the gangway of the AA walking down the jetty at Selfs Point to a waiting but that delivered us to Macquarie Wharf No 2 shed 10 minutes later where loved ones awaited our arrival. After a short ceremony welcoming returning expeditioners home and thanking them for their effort the expedition was ended. It was now time to reunite with family and friends.

Disembarking to catch the bus.

A Murky Detour.

Modus satellite image of algal bloom.

For some weeks an algal bloom had been observed near the Mawson coast from satellite images. The ship was directed to transit the bloom a number of times and biologists Susan, Julie and Josh on board the ship were rostered to conduct sampling so that the algae could be identified.

Algal bloom and pancake ice

The bloom was estimated to be around 200 km wide and 100 km long, and, while scientists aren’t exactly sure what caused the bloom, one theory is that it was caused by recent summer winds blowing iron off of the Antarctic continent. The iron acts as nutrient for what is thought to be phaeocystis algae. The bloom will benefit most of the food chain attracting predators chasing the smaller species that feed off the algae such as krill and other zoo plankton. The bloom should provide a bounty for penguins, seals and whales that will feed on the fish or the krill itself.

Algal bloom and pancake ice

The surface water colour was brownish when the ship encountered the bloom. A dirty brown scum was evident between the pancake ice on the water surface.

At designated 3 hour intervals over about 36 hours water samples were collected and then through filtering and centrifuge the algal samples were collected and preserved in vials for later analysis. Fluorescence, water temperature and salinity were also monitored.

Filtering

Preparing for centrifuge

Centrifuge

Concentrated algae sample

Monitoring while passing through bloom.

After completion of the algal sampling krill was collected from open water. This involved stopping the ship and using a special net to catch the krill. The resulting catch was kept in darkness in special tanks with fresh seawater constantly circulated through the tanks to ensure adequate oxygen supply. Any dead krill were removed each day to prevent fouling of the tanks.

Krill are about 2cm long and become orange when stressed.

The krill kept in darkness and without food are able to survive the journey back to Australia as they have the ability to be able to consume their own body mass, growing new shell for the smaller body as required.

Krill in tanks on board the AA.

Once the Derwent River estuary was entered the external water intakes to the krill tanks were closed. Estuary water is not suitable for krill as it contains fresh water.  Once fresh seawater is no longer available the krill need to be removed from the ship to the Antarctic Division Kingston facility within 6 hours before oxygen depletion in the water occurs. 

Special arrangements were made for their unloading from the refueling wharf at Selfs Point, Hobart when the ship docked..

Arrival and Departure of the AA.

AA tied up at Nella Rock - plaque remembering MV Nella Dan's sinking.

The afternoon of Tuesday 28th Feb saw the arrival of the Aurora Australis (AA) at Mawson. Arrival had been delayed 4 days by blizzard conditions at Mawson. It was with mixed feelings that I watched from the Met Office as the AA edged into the harbour and moored. Tying up process taking a couple of hours as the mooring crews secured each of the ropes to bollards. Moored near Nella rock, the ship points to the SE and is close in to the station to ride out any strong winds should there be a blizzard.

 The forecast weather conditions were good for the next 4 days resupply. and the AA was tied up by dusk, the ships presence in the harbour complete with lighting suddenly made the station seem more crowded. Passengers remained on board till the following morning when unloading commenced.

The new crew disembarked in the morning and were inducted to the station by Mark our station Leader. The new crew were accommodated in spare rooms of the living quarters. They also quickly became involved in resupply and handover activities with the outgoing crew.

The new crew is welcomed by Station Leader

During changeover skies were clear on a couple of nights and auroral activity made a spectacular display as it lit up the night sky.

The fuel lines are connected to station storage tanks.

Weather conditions enabled the connection of fuel lines on Friday and 604,000 litres Special Antarctic Blend (SAB) diesel was pumped to the on station storage tanks in under 24 hours. 

Unloading and back loading progressed well and on Saturday 4th March the mooring crew removed the ropes from the bollards and the IRB’s, floated them to the ship as they were drawn in. The AA then moved to Kista Strait to ensure it could make a quick getaway should the weather turn.

The official handover was conducted after 9:00pm when all work had ceased. The ceremony was conducted in the bar with Antarctic medals handed out to the outgoing crew and the keys of the station passed to the incoming crew.

The last of the back loading progressed through Sunday. All returning expeditioner bags were loaded at 11:00 am and those not needed ashore were moved to the ship at midday. At 15:00 pm the remainder of returning expeditioners were mustered with only time for a quick farewell and then ferried by Inflatable Rubber Boats (IRB’s) to the ship. On board the AA the finality of our year was sinking in. Meanwhile work needed to make the ship ready for departure

Rod and Lisa contemplate departure.

 

Dinner was served at 5:30 on the ship and we were advised that at 6:00pm the ship would be departing Mawson. Some low priority cargo - rubbish and a couple of quads were not loaded, resupply however was a success.

Mawson and the Masson ranges left behind.

A short window of opportunity allowed a last email or Internet access before the ship was beyond the reach of the wireless link from the station.

The evening was overcast, stratocumulus cloud with the occasional shaft of sunlight and snow shower escorting the AA into iceberg alley, north of Mawson as evening closed in.



Weather observations were commenced and the poor sailors amongst us retired to their bunks early.

The medical team was also swung into action attending to a patient in the ships hospital, under observation for a suspect appendix.

After 2 nights of around the clock nursing and monitoring the patient was discharged without further problems and the medical team was stood down.