Sunday 27 January 2008 à 11:48
An exclusive interview with Edi!
Sophie Mouge. Correspondent aboard the Aurora Australis
Today, to close our adventure on the Aurora Australis, I’d like to introduce you to a person we have much appreciated and who is indispensable on board. This is Edi, the ship’s doctor.
Saturday 26 January 2008 à 17:36
Awarding certificates
Sophie Mouge. Correspondent aboard the Aurora Australis
This morning, many of us wake to the sound of a thundering announcement: “Good morning to all expeditioneers! As you know, today is Australia Day. You are invited to the traditional Devonshire Tea in the mess at 10:00!”
Saturday 26 January 2008 à 17:31
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 44°01.034’ S
- longitude: 147°25.720’ E
Wind:
- direction: N-NE
- speed: 16 knots
Water temperature: 16.3 °C
Air temperature: 16.1 °C
Atmospheric pressure: 1,010 HPa
Relative humidity: 85 %
UV B: 7 W/m²
Water depth: 3,225 meters
Sunset: 20h46 / sunrise: 06h00
Saturday 26 January 2008 à 12:17
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 26/01/08
REPORT (SITREP) NO.: 340
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -47 57.5, 145 47.6
HEADING: 357T
CURRENT SPEED (KNOTS): 12.0 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): 187 to PULSE mooring
DISTANCE
COVERED LAST 24 HOURS (NAUTICAL MILES): 289.5
WEATHER CONDITIONS: Overcast
with low cloud, 7/8th cover, good visibility, winds 23 kts from 330T gusting
to 25 kts
AIR TEMPERATURE: 11.5
SEA TEMPERATURE: 11
SEA CONDITIONS: Vessel
rolling slightly in moderate seas and NW'ly swell 20-3m
ICE CONDITIONS: Nil
REMARKS: The swell has moderated significantly since yesterday and everyone
is much more comfortable as the ship gently rolls its way home via the PULSE
mooring at about 45S. People still busy packing, processing data and
preparing results. The partial pressure of CO2 (pCO2) in the ocean and
atmosphere will continue to be measured until we reach Tasmania. The region
of greatest CO2 concentration in the surface waters was measured at the
SubAntarctic front (-53.8 S), where oceanic pCO2 was up to 25% above
atmospheric levels. The SubAntarctic zone is a region of uptake for
atmospheric CO2 throughout the year, with the highest uptake over summer due
to shallower mixed layers and increased biological production. It is now
well known that even slight acidification of the ocean caused by rising
atmospheric CO2 levels will make it hard for some animals to build or
maintain calcium carbonate shells. The combination of benthic biologists and
chemists on the voyage has provided an excellent opportunity for exploring
the likely impact of ocean acidification on the sea-bed living animals
around Antarctica.
Regards, Martin and Sarah.
Friday 25 January 2008 à 17:28
Thanks to everyone!
Sophie Mouge. Correspondent aboard the Aurora Australis
The CEAMARC-CASO expedition on board the Aurora Australis is ending!
Friday 25 January 2008 à 17:25
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 47°22.711’ S
- longitude: 145°45.661’ E
Wind:
- direction: N
- speed: 23 knots
Water temperature: 11 °C
Air temperature: 11.9 °C
Atmospheric pressure: 1,010 HPa
Relative humidity: 80 %
UV B: 3 W/m²
Water depth: 3,225 meters
Sunset: 21h04 / sunrise: 05h54
Thursday 24 January 2008 à 17:22
Consolidating the data from the campaign
Sophie Mouge. Correspondent aboard the Aurora Australis
Our last night was a very short one. The party was a real success. We went to bed late (or early, depending on the person!). The ocean swells invited themselves and were particularly strong, which kept us from sleeping soundly.
Thursday 24 January 2008 à 17:18
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 51°74.062’ S
- longitude: 144°14.844’ E
Wind:
- direction: NW
- speed: 24 knots
Water temperature: 7.2 °C
Air temperature: 8.5 °C
Atmospheric pressure: 1,005 HPa
Relative humidity: 80 %
UV B: 7.7 W/m²
Water depth: 3,468 meters
Sunset: 21h29 / sunrise: 05h41
Thursday 24 January 2008 à 12:35
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 24/01/08
REPORT (SITREP) NO.: 339
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -52 25.3, 143 26.4
HEADING: 044T
CURRENT SPEED (KNOTS): 13.0 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): 466
DISTANCE COVERED LAST 24 HOURS (NAUTICAL MILES): 247.3
WEATHER CONDITIONS: Mostly cloudy, with sunny intervals, fine, good visibility, winds 25 kts from 270T gusting to 30 kts
AIR TEMPERATURE: 7.5
SEA TEMPERATURE: 7.6
SEA CONDITIONS: Rough seas and heavy W'ly swell 4m
ICE CONDITIONS: Nil
REMARKS: The heavy swell caused a bit of motion in the ship last night and the vessel course is being adjusted slightly to minimise discomfort while still making good speed. Although most of the scientific sampling is now complete, some will continue until we steam up the Derwent. The CO2 group are still measuring pCO2 in surface waters and the atmosphere, are taking 6 hourly underway samples for 02, CO2, salinity, nutrients and oxygen isotopes and are continuing to analyse CTD samples previously collected. The phytoplankton group are continuing with underway sampling of surface water from the seawater line 2 to 4 times per day to assess phytoplankton productivity. Most on board are continuing to process samples, collate data or prepare preliminary reports. Last night the ship's company was treated to a soiree-style entertainment featuring many of the very talented musicians and performers on board. Our thanks go to all involved for making it a very special occasion.
Regards, Martin and Sarah.
Wednesday 23 January 2008 à 17:11
The end of the mission draws near
Sophie Mouge. Correspondent aboard the Aurora Australis
The music group that came together on the ship from the beginning of the expedition is rehearsing seriously for the finale this evening.
Wednesday 23 January 2008 à 12:00
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 23/01/08
REPORT (SITREP) NO.: 338
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -56 31.5, 141 59.4
HEADING: 010T
CURRENT SPEED (KNOTS): 11.5 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): 700 DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 227.6
WEATHER CONDITIONS: Mostly cloudy, distant rain, winds 25 kts from 303T gusting to 30 kts
AIR TEMPERATURE: 4.7 SEA
TEMPERATURE: 4.3
SEA CONDITIONS: Moderate to rough seas and moderate WNW'ly swell 3m
ICE CONDITIONS: Nil
REMARKS: This morning the last of the CTD casts for genomic analysis of marine microorganisms near the seabed was taken in depths of a little over 3000m. The Continuous Plankton Recorder is now being towed behind the ship on the second of three deployments for the return journey. During each deployment it collects zooplankton from the near surface waters on a silk spool that is gradually wound past the opening in the CPR using a simple clockwork mechanism driven by a small propeller. When analysed, differences in the zooplankton community over the 400 mile deployment can be identified.
Everyone busy on board processing data, collating reports and preparing paperwork for arrival in Hobart.
Regards, Martin and Sarah.
Tuesday 22 January 2008 à 17:03
How to conserve Antarctic specimens that are collected?
Sophie Mouge. Correspondent aboard the Aurora Australis
The mission is reaching its end! We have to be sure that the specimens we’ve collected are well dried out. If they are not, there is a risk of organisms mildewing during the return trip, which will take them to different laboratories in several countries the world over.
Tuesday 22 January 2008 à 10:26
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 22/01/08
REPORT (SITREP) NO.: 337
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -60 23.7, 141 05.8
HEADING: 012T
CURRENT SPEED (KNOTS): 13.0 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): 1024.6
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 208.4
WEATHER CONDITIONS: Overcast with low cloud
and occasional fog patches, winds 21 kts from 260T
AIR TEMPERATURE: 3.1
SEA
TEMPERATURE: 3.1
SEA CONDITIONS: Moderate seas and W'ly swell 3m
ICE
CONDITIONS: Nil
REMARKS: The last of the 12 CASO CTD casts along the SR3 transect was
completed at 2000 hrs last night. This was the 130th CTD for the voyage,
with 44 samples taken along the CASO transects and a further 86 at the
CEAMARC sites. The SR3 transect was first occupied in 1991 by Aurora
Australis; the present voyage will be the 7th re-occupation of the line.
The time series of measurements along SR3 is the longest and most continuous
set of observations available to document changes in the deep and bottom
waters of the Southern Ocean. The CASO CTD stations east of the Mertz
Glacier taken earlier in the voyage showed clearly that the bottom water
flowing west from the Ross Sea is significantly fresher than observed in the
1990s. The SR3 line of stations just completed will show whether the bottom
water produced in the Mertz Polynya region is also changing. The CTD samples
taken at the CEAMARC sites will provide key information on physical
conditions in the overlying waters that may help explain the distribution
and abundance patterns seen in the communities of bottom-living animals.
With an average depth of about 1300m for all 130 sites, a total of about
170kms of CTD wire has been paid out from the winch and wound back in again
during the course of the voyage.
Regards, Martin and Sarah.
Monday 21 January 2008 à 16:51
Measure, weigh, sex, sample
Sophie Mouge. Correspondent aboard the Aurora Australis
The last work is going on in the wet lab. The scientists have spent a total of three weeks sampling specimens brought up from the Southern Ocean.
Monday 21 January 2008 à 16:42
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 63°50.823’ S
- longitude: 139°53.775’ E
Wind:
- direction: W
- speed: 12 knots
Water temperature: 1.9 °C
Air temperature: 2.2 °C
Atmospheric pressure: 984 HPa
Relative humidity: 100 %
UV B: 5 W/m²
Water depth: 3,750 meters
Sunset: 23h18 / sunrise: 04h26
Monday 21 January 2008 à 16:16
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 21/01/08
REPORT (SITREP) NO.: 336
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -63 52, 139 52.6
HEADING: 080T
CURRENT SPEED (KNOTS): 0 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 96.1 Nm
WEATHER CONDITIONS: In fog, poor visibility
to less than 0.5 nm, light winds 8 kts from 295T
AIR TEMPERATURE: 1.6
SEA
TEMPERATURE: 1.3
SEA CONDITIONS: Slight seas and moderate W'ly swell to 2-3m
ICE CONDITIONS: Nil, Open water.
REMARKS: After finishing the CEAMARC survey at midnight a day and a half ago
we steamed to the start of a series of 12 CASO CTD water sampling sites in a
transect from the edge of the continental shelf northwards into the Southern
Ocean. At the time of writing we are sampling the last but one of these,
with the final samples to be collected at latitude 63 21S this evening from
just below the sea surface to just above the seabed at a depth of 3812m. If
the Aurora Australis were a large orange hot-air balloon flying over Hobart
at this height above sea-level and attempting to sample the air down to the
surface of Constitution Dock it would be floating at three times the height
of Mt Wellington (1270m).
Regards, Martin and Sarah.
Sunday 20 January 2008 à 18:25
Crustaceans in Antarctica?
Sophie Mouge. Correspondent aboard the Aurora Australis
My name is Bertrand Richer de Forges and I am a specialist in crustaceans (malacostracans). In these few lines, I propose to lead you on an exploration of this group.
Sunday 20 January 2008 à 18:14
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 65°17.603’ S
- longitude: 139°52.812’ E
Wind:
- direction: W
- speed: 25 knots
Water temperature: -0.6 °C
Air temperature: -1 °C and -20 °C in the wind!
Atmospheric pressure: 990 HPa
Relative humidity: 75 %
UV B: 2.7 W/m²
Water depth: 2,750 meters
Sunset: 23h42 / sunrise: 04h01
Sunday 20 January 2008 à 16:15
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 20/01/08
REPORT (SITREP) NO.: 335
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 24.7, 139 50.7
HEADING: 329T
CURRENT SPEED (KNOTS): 4.4 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 70 Nm
WEATHER CONDITIONS: Overcast, visibility good,
wind 27 kts gusting to 30 kts from 275T
AIR TEMPERATURE: -1.5
SEA
TEMPERATURE: 0.7
SEA CONDITIONS: Moderate seas and NW swell to 2.5m
ICE
CONDITIONS: Nil, Open water.
REMARKS: Yesterday water samples were collected from 7 sites at a range of
distances from the large ice-berg using the Fast Rescue Craft (FRC). While
sampling was happening, the Aurora Australis maintained its position
down-wind and down-current to ensure there was no risk of the ship
contaminating the surface waters. These samples are to be analysed for
ultra-low levels of trace elements and even the presence of the ship's hull
in the immediate sampling area could compromise the results. Recovery of the
FRC was delayed while a mechanical problem was fixed. The ship then returned
to each of the sites sampled from the FRC and took a CTD sample to be used
to define the extent of influence of melt water from the iceberg. We
returned to the CEAMARC canyon site just before the shift change at midnight
to resume sampling with the intention of deploying the trawl mounted digital
camera in a transect from 850m to 1300m. The plan was to document the
transition from the abundant shallower fauna to the less diverse deeper
communities and then to sample with the French beam trawl. Unfortunately, by
this time the wind was too strong to maintain the ship on the correct course
at the low speeds required for trawling. Prudence dictated it was time to
call a halt and CEAMARC sampling officially finished at 8 minutes past
midnight. Overall, 82 different sites were occupied during CEAMARC, with
samples collected from at least 78 sites; well in excess of the 67 sites we
had hoped for. Everyone involved is to be congratulated for putting in an
enormous and sustained effort to achieve such an excellent result.
Regards, Martin and Sarah.
Saturday 19 January 2008 à 16:14
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 19/01/08
REPORT (SITREP) NO.: 334
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 37.0, 141 05.3
HEADING: 022T
CURRENT SPEED (KNOTS): 4 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 102.3 Nm
WEATHER CONDITIONS: Low cloud, sunny
intervals, passing snow flurries, visibility variable, wind 14 kts gusting
to 15 from 270T
AIR TEMPERATURE: 0.2
SEA TEMPERATURE: 1.2
SEA CONDITIONS:
Slight seas and low confused swell
ICE CONDITIONS: Very large iceberg 2
miles to port, numerous smaller bergs on radar, bergy bits and growlers
nearby, otherwise open water.
REMARKS: As predicted, sampling the very rugged seabed in this canyon system
at the edge of the continental shelf has been difficult. The results,
however, have been well worth the effort. At the cost of some torn trawl
nets, we have managed to get imagery and samples down to 1500m, with the
very diverse seabed offering up a similarly diverse fauna. Last night we
recorded the most fish species from any one trawl - 16 including at least
one which was new to this survey. The benthic invertebrates were similarly
diverse with a great range of sedentary groups, such as sponges, bryozoans
(lace coral), tunicates (sea squirts), gorgonians and some very large
solitary corals, forming the main supporting structure for an equally
diverse variety of mobile groups such as polychaete worms, amphipod
crustaceans, ophuroids (brittle stars), crinoids (feather stars), echinoids
(sea urchins), asteroids (sea stars), pycnogonids (sea spiders) and a range
of molluscs. Early this morning we stopped the benthic work temporarily and
switched our efforts to sampling the waters around the very large ice-berg
nearby, with the intention of identifying whether it is a source of trace
nutrients that might stimulate plankton growth. Satellite imagery indicates
the iceberg is about 35 km long by 18 km wide. If it is 400m deep, it
contains 252,000,000,000,000 litres of water or 12 million litres for every
one of the 21 million Australians. You would need a pool 3m deep by 40m wide
by 100m long to hold your share. The berg is designated B-17A and came into
this region in October 2006. It comes from a large chunk of the Ross Ice
Shelf that calved between 160-165W in April 2000. This section subsequently
broke up, with other fragments heading in the opposite direction.
Regards, Martin and Sarah.
Saturday 19 January 2008 à 15:42
Fishing for water on the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
After 78 CTD stations, some 1,200 bottles of water have been sampled by Steve Rintoul’s team. The Aurora Australis is heading today for an iceberg known in the region since 2006.
Saturday 19 January 2008 à 15:33
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 65°35.669’ S
- longitude: 141°35.380’ E
Wind:
- direction: W
- speed: 12 knots
Water temperature: -1 °C
Air temperature: -0.2 °C
Atmospheric pressure: 982 HPa
Relative humidity: 75 %
UV B: 7.3 W/m²
Water depth: 1,330 meters
Sunset: 23h47 / sunrise: 03h49
Friday 18 January 2008 à 15:54
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 18/01/08
REPORT (SITREP) NO.: 333
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 39.7, 140 32.8
HEADING: Various
CURRENT SPEED (KNOTS): 2 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 102.3 Nm
WEATHER CONDITIONS: Partly cloudy,
otherwise fine and sunny, good visibility, wind 7 kts from 60T
AIR
TEMPERATURE: 1.0
SEA TEMPERATURE: 1.0
SEA CONDITIONS: Slight seas and
moderate WNW swell 3-4 m
ICE CONDITIONS: Scattered grounded bergs including
one very large berg (~35km long) to the NNE, otherwise open water.
REMARKS: We are now sampling the second of the transects into deep water
over the edge of the continental shelf. This one is down the path of what
appears to be a drainage canyon based on detailed multi-beam imagery. The
sea-bed here is very rugged and the sampling is particularly difficult -
which is the reason why it was left to the end of the CEAMARC phase of the
voyage. There is too much risk of damaging the gear for us to have attempted
it earlier. However, the deck crew have done an excellent job of deploying
the equipment over very difficult terrain and we have been rewarded with
superb imagery and samples. We are again seeing many of the species that
previously were only found in the 'coral garden' reported down a similar
slope in the western sector. Here the diversity appears to be somewhat
greater as it is not so completely dominated by a few very abundant species.
We had contact with a second fishing vessel yesterday afternoon, owned by
the same company as the one seen a day ago.
Regards, Martin and Sarah.
Friday 18 January 2008 à 15:27
Parade of stars on the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
The popping flashes echo from a distance. Passing before the door to the wet lab, we are blinded by the dazzling and constant bolts of light that filter through the little window. The rumor that has been flying for a bit is finally confirmed: the stars are among us!
Friday 18 January 2008 à 15:20
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude : 65°41.716’ S
- longitude : 140°32.699’ E
Wind:
- direction: SE
- speed: 7 knots
Water temperature: 0.9 °C
Air temperature: -0.8 °C
Atmospheric pressure: 982 HPa
Relative humidity: 80 %
UV B: 7.7 W/m²
Water depth: 623 meters
Sunset: 00h58 / sunrise: 3h47
Thursday 17 January 2008 à 15:16
A day without end (through the eyes of Team Leader Catherine Ozouf).
Sophie Mouge. Correspondent aboard the Aurora Australis
23h30: The alarm clock rings. I jump out of bed, boot up the computer and rush to the shower: a great way to wake up!
Thursday 17 January 2008 à 15:05
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude : 65°28.048’ S
- longitude : 139°20.812’ E
Wind:
- direction: SE
- speed: 7 knots
Water temperature: 0.7 °C
Air temperature: 1.3 °C
Atmospheric pressure: 978 HPa
Relative humidity: 72 %
UV B: 7.7 W/m²
Water depth: 830 meters
Sunset: 00h58 / sunrise: 3h47
Thursday 17 January 2008 à 13:34
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 17/01/08
REPORT (SITREP) NO.: 332
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 26.7, 139 18.2
HEADING: Various
CURRENT SPEED (KNOTS): 2 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 86.5 Nm
WEATHER CONDITIONS: Partly cloudy, otherwise
fine and sunny, good visibility, wind 10 kts from 135T
AIR TEMPERATURE: -1.5
SEA TEMPERATURE: 0.9
SEA CONDITIONS: Slight seas and low ENE swell 0.5 m
ICE
CONDITIONS: Distant bergs, otherwise open water.
REMARKS: We are currently sampling one of two planned transects from shallow
(400m) to deep water (1200m) over the edge of the continental shelf. Last
night we ran the trawl-mounted still camera down the slope for two hours and
got some excellent images of the gradually changing sea-bed. We have also
trawled across the slope, at 400m, 800m and 1200m, to collect the animals
seen on the photographs, sampled the watercolumn with the CTD and, where the
sediment was suitable, collected sea-bed sediments. Yesterday we had two
failed trawls at 400m, one because the cod-end blew out, the other collected
a single very large rock which damaged the net. We are now returning to the
400m site for one last attempt before moving on to the next transect about
20 miles to the east. At about mid-day yesterday we met a fishing vessel
very close to our planned sampling sites. While manoeuvring to identify it
we acquired densely spaced depth data using the underway data logging
system. This was quickly manipulated by our Data Manager to produce a very
accurate bathymetric chart that proved to be very useful in deciding the
best line for running the transects.
Regards, Martin and Sarah.
Wednesday 16 January 2008 à 16:33
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 16/01/08
REPORT (SITREP) NO.: 331
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 55.2, 139 18.3
HEADING: 357
CURRENT SPEED (KNOTS): 12 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 96.2 Nm
WEATHER CONDITIONS: Overcast with 8/8ths low
cloud, occasional snow falls, poor visibility, wind 6 kts from 290T gusting
to 10 kts
AIR TEMPERATURE: -0.2
SEA TEMPERATURE: 0
SEA CONDITIONS: Rippled
to slight seas and low NNW swell 0.5 m
ICE CONDITIONS: Isolated bergs and
occasional growlers, otherwise open water.
REMARKS: The run of good weather and cooperative sea-ice continues. In the
past 24 hrs a further 7 sites were sampled, with the night shift once again
completing 4 sites in their 12 hr watch. At mid-day today we had sampled 68
sites, one more than the total of 67 originally planned. We are now sampling
the first of the additional transects in to deep water over the edge of the
continental shelf. The sea-ice has been particularly kind to us - only a few
days ago the western-most sites we sampled yesterday were covered with
sea-ice and were inaccessible for sampling. The high resolution satellite
imagery available to the ship has been invaluable in making decisions about
where and when to attempt sampling throughout the voyage. 56 species of fish
have now been collected, with 16 species added to the list during this
second phase of CEAMARC sampling in the western sector. More than 40 rapid
spleen and cephalic kidney cell cultures have been prepared from a wide
range of fish species and the best ones will be used later for comparative
gene mapping. Primary fibroblast cell lines have been prepared from species
representing the most important families of Antarctic notothenioids and
successfully grown up for, as far as we know, the first time on board a
ship. These will be used for genomic studies on the adaptations of Antarctic
fish to their environment.
Regards, Martin and Sarah.
Wednesday 16 January 2008 à 15:02
Not all equal before the trawl.
Sophie Mouge. Correspondent aboard the Aurora Australis
Each time a drag net is hauled up on the trawl deck of the Aurora Australis, the entire shift is ready to spring into action, outfitted in orange combat suits!
Wednesday 16 January 2008 à 14:58
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 65°35.519’ S
- longitude: 139°15.694’ E
Wind:
- direction: N-W
- speed: 15 knots
Water temperature: - 0.5 °C
Air temperature: - 0.2 °C
Atmospheric pressure: 985 HPa
Relative humidity: 96 %
UV B: 2.7 W/m²
Water depth: 440 meters
Sunset: 00h04 / sunrise: 3h41
Tuesday 15 January 2008 à 14:53
Sailing in unknown waters
Sophie Mouge. Correspondent aboard the Aurora Australis
Did you know that the moon surface is better known than the topography of the oceans depths. Surprising isn’t it ?
Tuesday 15 January 2008 à 14:46
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude : 66°23,509’ S
- longitude : 139°48,106’ E
Wind:
- direction: E
- speed: 2 knots
Water temperature: - 1,3 °C
Air temperature: 2,5 °C
Atmospheric pressure: 984 hPa
Relative humidity: 42%
UV-B: 8 W/m²
Water depth: 920 meters
Sunset: 00:26/ sunrise: 03:14
Tuesday 15 January 2008 à 11:27
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 15/01/08
REPORT (SITREP) NO.: 330
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 24.4S, 139 47.6E
HEADING: Various
CURRENT SPEED (KNOTS): 0 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 78.8 Nm
WEATHER CONDITIONS: Clear skies and good
visibility, wispy high cloud, light wind 4 kts from 62T
AIR TEMPERATURE:
0.5
SEA TEMPERATURE: -1.2
SEA CONDITIONS: Calm seas, low E'ly swell 0.5 m
ICE CONDITIONS: Frequent icebergs, bergy bits and growlers, vessel running
in clear water along edge of pack-ice.
REMARKS: Trying to sample the deep (1200 m) basin yesterday was very
frustrating. Twice we had the cod-end of the trawl blow out and recovered
only a very small haul retained by the coarser outer mesh. The trawl-mounted
video camera provided only brief but tantalising glimpses of a sea-bed
covered with large numbers of surface feeding sea-cucumbers between long
periods of total darkness, caused when the trawl sank to its armpits in the
fine diatomaceous ooze. After about 10 hours of trying we moved on to the
next site at 800m on the basin slope and, while sampling, considered options
for completing the deep basin. The 800m site was sampled in reasonable time,
so we returned to the deep site and deployed the French beam with the
intention of floating it briefly across the bottom. In the event the trawl
was on the bottom for about 8 minutes and came up with a fine haul. The
community was dominated by the large elasipodid sea-cucumbers seen on the
video, looking very like fat little hippopotamuses grazing on the sea-bed,
but included many other species including sea-stars (similar to Acodontaster
and Cuenotaster), brittle stars (cf Astrotoma), stalked tunicates (cf
Molgula), large gastropods, many small bivalves and several pelagic octopus.
The night shift then took over and made up for lost time, completing 4 sites
before retiring exhausted. We are well on track to meet our original
sampling plan, having completed 91% of sites with 85% of time used. If the
weather holds, we will have some time in hand when we have completed the
original 67 sites and will use this to sample extra sites in transects over
the shelf break to compare with those from the western sector.
Regards, Martin and Sarah.
Monday 14 January 2008 à 15:55
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 26.4S, 140 31.3E
HEADING: Various
CURRENT SPEED (KNOTS): 2.5 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 113.9 Nm
WEATHER CONDITIONS: Clear skies and good
visibility, wind decreasing 20 kts from 102T gusting to 25 kts
AIR
TEMPERATURE: 0.3
SEA TEMPERATURE: -0.7
SEA CONDITIONS: Moderate seas and
moderate confused swell 2-3 m
ICE CONDITIONS: Frequent large icebergs
otherwise open water, ice covered continent in sight.
REMARKS: With only a few days of sampling left, weather forecasts and
sea-ice conditions from satellite imagery are being continually reviewed and
plans fine-tuned to ensure we make the best use of the available time.
Yesterday it seemed that some planned sites to the west would be covered in
dense pack-ice and not easily reached. The strong south-easterly winds last
night which gusted to more than 30 kts, however, seemed to have worked in
our favour, moving the edge of the pack-ice westwards and clearing these
sites. As a consequence we will try to sample them. Yesterday's shallow
sites (~200m) proved to be very diverse with complex multi-layered sponge
and bryozoan dominated communities. Unfortunately the trawl with the digital
camera which has been providing us with such excellent images of the sea-bed
suffered some damage when it landed up-side down. The Science Technical
Support wizards have been busy fixing it overnight and it should be
operational again soon. The French beam trawl was used at two sites
yesterday and it proved very efficient, collecting very large hauls and
appearing to retain some of the smaller infauna that may be lost through the
mesh of the AAD trawls. We are currently sampling from the bottom (1200m) of
a closed basin northeast of Dumont D'Urville, which appears to be a trap for
fine sediment - more about this tomorrow.
Regards, Martin and Sarah.
Monday 14 January 2008 à 14:43
Stefan Chilmonczyk ‘hunt’ for Channichthyids
Sophie Mouge. Correspondent aboard the Aurora Australis
Today as everyday, I hope for the presence of a Channichthids specimen in the trawl that comes from the bottom of the southern ocean.
Monday 14 January 2008 à 14:35
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude : 66°26,639’ S
- longitude : 140°31,497’ E
Wind:
- direction: E-SE
- speed: 12 knots
Water temperature: - 0,8 °C
Air temperature: 0,2 °C
Atmospheric pressure: 985 hPa
Relative humidity: 75%
UV-B: 7.6 W/m²
Water depth: 1030 meters
Sunset: 00:29/ sunrise: 03:04
Sunday 13 January 2008 à 16:11
Unusual fishes !
Sophie Mouge. Correspondent aboard the Aurora Australis
We are in trouble ! The sea-ice cover in the water off Dumont D’Urville is at time very important. At 4 am we spot a wall of tabular icebergs in the distance !
Sunday 13 January 2008 à 15:57
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 13/01/08
REPORT (SITREP) NO.: 328
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 03.7S, 141 17.7E
HEADING: 172
CURRENT SPEED (KNOTS): 13.3 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 116.1 Nm
WEATHER CONDITIONS: Mostly low cloud 6/8ths
cover, moderate to good visibility, wind 18 kts from 115T gusting to 22 kts
AIR TEMPERATURE: -1.0
SEA TEMPERATURE: -0.5
SEA CONDITIONS: Slight to
moderate seas and low E'ly swell 0.5 m
ICE CONDITIONS: Frequent large
icebergs otherwise open water.
REMARKS: This second phase of CEAMARC benthic sampling started very well
with 6 stations completed in the last 24 hrs. We have now caught up with the
planned sampling schedule, having 24% of sites left to do and 25% of the
total time allocated to CEAMARC to do them in. If the weather remains kind
to us we should complete the schedule as planned. The only slight variation
being the re-location of some sites to avoid dense pack-ice on longitude
140E directly north of the French research station at Dumont D'Urville. We
have also re-aligned some sites, on the basis of very accurate bathymetry
obtained using a multi-beam swath mapping depth sounder, to get better
series of samples from shallow to deep. Yesterday's samples from 400m, 800m
and 1100m were a very interesting contrast to those from a similar depth
series reported in sitrep 321, which at 800m was dominated by a colourful
garden of filter-feeding coralline species. Yesterday's 800m site had a very
sparse covering of surface-living filter-feeders, such as sponges and
bryozoans, but had very large numbers of Macrourus whitsoni or rat-tails, a
common fish from these depths throughout the world. The sea-bed photographs
indicated a lot of 'marine snow' (organic particulates) in the water and a
piscean wall of mouths - fish waiting on the seabed for food to be washed
past them by the currents. So although only 20 miles apart and sharing the
common characteristics of very high productivity and biomass the benthic
fauna at these sites were intriguingly different.
Regards, Martin and Sarah.
Sunday 13 January 2008 à 11:43
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
latitude: 65°15,769’ S
longitude: 141°17,882’ E
Wind:
direction: E
speed: 18 knots
Water temperature: -0,2 °C
Air temperature: 0,2 °C
Atmospheric pressure: 992 HPa
Relative humidity: 75 %
UV-B: 3,9 W/m²
Water depth: 241 meters
Sunset: 00h27/ sunrise: 3h00
Saturday 12 January 2008 à 11:36
Astrolabe in sight!
Sophie Mouge. Correspondent aboard the Aurora Australis
We are now sailing in the Antarctic water off Adélie Land.
Saturday 12 January 2008 à 11:28
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
latitude: 65°54,744’ S
longitude: 146°58,153’ E
Wind:
direction: N
speed: 3 knots
Water temperature: 0°C
Air temperature: 1.2°C
Atmospheric pressure: 985 hPa
Relative humidity: 68%
UV-B: 7.8 W/m²
Water depth: 375 meters
Sunset: 00h09/ sunrise: 02h55
Friday 11 January 2008 à 18:21
So much water!
Sophie Mouge. Correspondent aboard the Aurora Australis
The Antarctic ice cap constitutes 90% of the world’s reserves of freshwater with 30 millions km3 of continental ice. This ice cap lays on the continental base and is made of ice coming from the accumulation of precipitations.
Friday 11 January 2008 à 17:39
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
latitude: 62°52.370' S
longitude: 146°34.062’ E
Wind:
direction: S
speed: 23 knots
Water temperature: -1°C
Air temperature: -2.7°C and -21°C in the wind
Atmospheric pressure: 980 hPa
Relative humidity: 85%
UV-B: 4.5 W/m²
Water depth: 908 meters
Sunset: 00h02/ sunrise: 02h41
Friday 11 January 2008 à 14:13
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 11/01/08
REPORT (SITREP) NO.: 326
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 49.6S, 146 35E
HEADING: 174
CURRENT SPEED (KNOTS): 5 kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 125.6 Nm
WEATHER CONDITIONS: Overcast with low level
cloud 7/8ths, moderate to good visibility, wind 20 kts from 165T gusting to
27 kts
AIR TEMPERATURE: -2.6
SEA TEMPERATURE: -1.1
SEA CONDITIONS: Moderate
to rough seas and moderate SSE swell 2 m
ICE CONDITIONS: Scattered bergs and
some bergy bits.
REMARKS: Yesterday we continued to meet dense pack ice as we attempted to
head south along the CASO CTD transect west of the Mertz Glacier. Rather
than spend time pushing against the ice we decided to move to the middle of
the three CASO transects, to sample along longitude 147E to the north of the
Mertz. We completed 2 of the sites along this transect before again meeting
dense pack ice and once more moved slightly west. We have now completed 3
sites along 146 35E. Satellite imagery indicates that the sites directly to
the south of our current position should be clear. The CTD data indicates
that we are again positioned over an outflow of bottom water generated by
the Mertz Polynya as it pours off the continental shelf, in contrast to the
Ross Sea bottom water detected further east. This is the first time it has
been confirmed that Mertz bottom water streams over the shelf in more than
one place. Over the past few days we have collected water samples from as
deep as 4000 m. At this depth the pressure is about 400 times atmospheric
pressure, to put this in perspective, if you opened a full diving cylinder
at this depth the pressure would force water into the cylinder and fill
about a quarter of it rather than allow the air out. Our plan is to complete
this phase of CASO sampling by about 1800 this evening, then to steam to the
polynya moorings to take advantage of a weather window to again move the
Pole Compass, before re-starting the CEAMARC sea-bed sampling.
Regards, Martin and Sarah.
Thursday 10 January 2008 à 13:55
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 10/01/08
REPORT (SITREP) NO.: 325
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 23.6S, 149 29.6E
HEADING: Various
CURRENT SPEED (KNOTS): 0 Kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 120.2 Nm
WEATHER CONDITIONS: Overcast with low
cloud, good visibility, wind 18 kts from 330T gusting to 23 kts
AIR
TEMPERATURE: 0.0
SEA TEMPERATURE: -1.6
SEA CONDITIONS: Moderate seas and WNW
swell 3 m
ICE CONDITIONS: Frequent ice-berg, ship sitting in open water
close to edge of pack-ice.
REMARKS: We are continuing working southwards, sampling along the eastern
transect of the CASO circuit. This morning we deviated slightly to the west
to avoid dense pack-ice that accumulates to the north and east of the Mertz
Glacier. To avoid speending time pushing through the sea ice we have
re-located the sampling sites so that they follow the ice edge southwards
towards the continental shelf break. On each of the CASO stations we have
occupied so far we can see a distinct layer of cold, oxygen-rich bottom
water near the sea-floor. There is, however, a clear contrast between the
bottom water measured on the western and eastern CASO legs. In the west, we
sampled the bottom water formed in the Mertz polynya area, which is fresher
than the water above it and particularly rich in oxygen and
chlorofluorocarbons (CFCs). In the east, the bottom water is lower in oxygen
and is much saltier, indicating this water was formed in the Ross Sea and
has travelled west through the deep channel south of the Balleny islands.
Regards, Martin and Sarah.
Thursday 10 January 2008 à 11:08
A hole in the ozone layer
Sophie Mouge. Correspondent aboard the Aurora Australis
Big areas of pack ice are surrounding the ship… For those of us present on the bridge this morning, this allows us to spot the first emperor penguins of the voyage!
Thursday 10 January 2008 à 10:53
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
latitude: 62°24.520' S
longitude: 149°12.330’ E
Wind:
direction: N
speed: 10 knots
Water temperature: -1.6°C
Air temperature: 0.3°C
Atmospheric pressure: 982 hPa
Relative humidity: 85%
UV-B: 5.4 W/m²
Water depth: 3,000 meters
Sunset: 23h42/ sunrise: 02h39
Wednesday 9 January 2008 à 15:55
The oceans "skin"
Sophie Mouge. Correspondent aboard the Aurora Australis
Jamie, the Third Officer, profits from the day full of sunshine to practice using the sextant.
Wednesday 9 January 2008 à 15:44
Data for the Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 63°59.800' S
- longitude: 150°01.280’ E
Wind:
- direction: N-NW
- speed: 13 knots
Water temperature: 0.2°C
Air temperature: 1.6°C
Atmospheric pressure: 982 hPa
Relative humidity: 88%
UV-B: 7.2 W/m²
Water depth: 3,670 meters
Sunset: 23h11/ sunrise: 03h02
Wednesday 9 January 2008 à 13:54
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 09/01/08
REPORT (SITREP) NO.: 329
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -63 54S, 150 00E
HEADING: Various
CURRENT SPEED (KNOTS): 0 Kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 149.8 Nm
WEATHER CONDITIONS: Sunny with some low
cloud, good visibility, wind 15 kts from 335T gusting to 18 kts
AIR
TEMPERATURE: 0.8
SEA TEMPERATURE: 0.2
SEA CONDITIONS: Slight seas and low
confused swell 0.5 m
ICE CONDITIONS: Open water.
REMARKS: We have turned the corner on the main CASO sampling loop and are
once again heading south. As I write we are at the fourteenth of the 31 CASO
stations in this phase of the voyage and have completed the first two legs
of the CASO stations over the Antarctic continental slope and rise. The
first leg followed a deep canyon running from south to north that drains the
bottom water produced in the Mertz polynya region. We found clear evidence
that even now, in summer, dense water produced during the winter is spilling
off the shelf and cascading down the canyon. The southwards leg that we are
now doing, to the east of the Mertz polynya outflow, is a repeat of stations
occupied during the BROKE expedition in 1996. Here we are sampling bottom
water flowing west from the Ross Sea. In previous work, Steve Rintoull and
others showed that the bottom water of the entire Australian - Antarctic
Basin became lower in salinity between the early 1970s and 2001. By
comparing the bottom water properties on the different legs of CASO, we will
be able to determine, first, if the bottom waters are continuing to change,
and second, the relative contribution of the Ross Sea and the Mertz polynya
to changes in the deep branch of the global overturning circulation.
Regards, Martin and Sarah.
Tuesday 8 January 2008 à 13:17
Under pressure!
Sophie Mouge. Correspondent aboard the Aurora Australis
The participants in the CEAMARC program have a few days off and are using the respite to edit their first reports. The Aurora Australis’s trawls are idle while the CASO (Climate of Antarctica and Southern Ocean) program’s operations are underway.
Tuesday 8 January 2008 à 11:51
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 63°03.350' S
- longitude: 146°29.270’ E
Wind:
- direction: NW
- speed: 10 knots
Water temperature: -0.8°C
Air temperature: 4°C
Atmospheric pressure: 986 hPa
Relative humidity: 85%
UV-B: 4.9 W/m²
Water depth: 3,950 meters
Sunset: 23h11/ sunrise: 03h30
Tuesday 8 January 2008 à 09:53
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 08/01/08
REPORT (SITREP) NO.: 323
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -62 58S, 145 44E
HEADING: 101T
CURRENT SPEED (KNOTS): 13 Kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): 20 Nm
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 143.9 Nm
WEATHER CONDITIONS: Cloud clearing to leave
some patchy, high cloud, good visibility, wind 5 kts from 320T
AIR
TEMPERATURE: 1.0
SEA TEMPERATURE: 0.7
SEA CONDITIONS: Slight seas and low
confused swell 0.5 m
ICE CONDITIONS: Open water.
REMARKS: CTD sampling of waters from the sea-surface to the seabed continues
around the clock for the CASO (Climate of Antarctica and the Southern Ocean)
part of V3. CASO is a major multinational project for the International
Polar Year involving scientists from 18 nations and is led by Australia.
CASO will provide the first circumpolar snapshot of the physical and
biogeochemical state of the Southern Ocean as a benchmark for the assessment
of past and future change. It will also demonstrate the feasibility of a
sustained Southern Ocean observing system. CASO will continue on V6, during
which a transect from Hobart to Antarctica will be sampled. On V3, CASO is
focused on the region close to the Antarctic continental shelf and the fate
of cold, dense 'Antarctic Bottom Water' from the Mertz Polynya. This region
is one of the few places in the ocean where surface waters are made
sufficiently dense to allow them to sink to the deep ocean. This transfer
of water from the surface to the abyss is part of a global system of ocean
currents known as the overturning or thermohaline circulation, which
strongly influences Earth's climate. Our measurements on V3 are aimed at
understanding how the Antarctic contribution to this global current system
works and whether it is changing. We are presently re-occupying sites first
measured on Aurora Australis in the 1994-5 season and are making excellent
progress in unusually calm conditions. Last night we sampled the
northern-most site, nearly 250 miles from the continent and are now heading
east to sample some of the deepest sites which are about 4 kilometres from
the surface to the seabed. Being this far north, we experienced our first,
brief nightfall for the year last night.
Regards, Martin and Sarah.
Monday 7 January 2008 à 14:35
How beautiful it is "down under"!
Sophie Mouge. Correspondent aboard the Aurora Australis
The last trawls of the first part of the CEAMARC program were put in the water last weekend.The trawl that was towed at 800 meters came back up so full that the net tore just as it was about to be hauled up on the trawl deck.
Monday 7 January 2008 à 14:18
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 63°48.380' S
- longitude: 143°21.415’ E
Wind:
- direction: S-SE
- speed: 10 knots
Water temperature: -0.8°C
Air temperature: -0.6°C
Atmospheric pressure: 982 hPa
Relative humidity: 85%
UV-B: 6.8 W/m²
Water depth: 4,200 meters
Sunset: 23h38/ sunrise: 03h26
Monday 7 January 2008 à 13:51
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 07/01/08
REPORT (SITREP) NO.: 322
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 56S, 143 21E
HEADING: 001T
CURRENT SPEED (KNOTS): 13 Kts
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): n/a
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 127.6 Nm
WEATHER CONDITIONS: Mostly cloudy, good
visibility, wind 12 kts from 180T
AIR TEMPERATURE: -0.3
SEA TEMPERATURE: 0.8
SEA CONDITIONS: Slight seas, low NE'ly swell 1m
ICE CONDITIONS: Open water.
REMARKS: We are now well into the main CASO (Climate of the Antarctic and
Southern Ocean) leg of the voyage. We will spend 6.3 days (oceanographers
can be very precise) using the CTD to sample the water column from 31 sites
in a large loop that will take us about 150 Nm northwards from the shelf
break and then east for a similar distance before heading south again to
return to the shelf break. At our current location the water is about 3600 m
deep and each CTD cast is taking about two and half hours. During this
circuit we will sample three canyon systems discovered using multi-beam
sea-bed imagery obtained by US and Italian survey vessels. These canyons are
thought to drain the cold dense Antarctic bottom water formed in the Mertz
Polynya.
Regards, Martin and Sarah.
Sunday 6 January 2008 à 17:48
Hump day with humpback whales
Sophie Mouge. Correspondent aboard the Aurora Australis
"Happy hump day!" is written today on the slate in the dining room. No one seems surprised, except for the non-English-speakers who are asking what message means.
Sunday 6 January 2008 à 17:33
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 65°32.021' S
- longitude: 143°09.419’ E
Wind:
- direction: SE
- speed: 7 knots
Water temperature: -0.2°C
Air temperature: -0.8°C
Atmospheric pressure: 991 hPa
Relative humidity: 82%
UV-B: 4.1 W/m²
Water depth: 2,700 meters
Sunset: 00h24/ sunrise: 02h42
Sunday 6 January 2008 à 13:50
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 06/01/08
REPORT (SITREP) NO.: 321
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -65 39.6S, 143 02.4E
HEADING: Various
CURRENT SPEED (KNOTS): 1.0
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 61.6
WEATHER CONDITIONS: Cloudy, good visibility,
wind decreasing 8 kts from 125T
AIR TEMPERATURE: -0.5
SEA TEMPERATURE: -0.2
SEA CONDITIONS: Slight seas, confused swell ICE CONDITIONS: Isolated bergs,
occasional bergy bits, otherwise open water.
REMARKS: We all expected the Big Polychaete to be the undisputed highlight
of the voyage, however, the Southern Ocean continues to turn-up surprises.
Yesterday, while sampling the transect from 400m to 2100m down the shelf we
blew out the trawl net as we tried to bring it on deck after sampling the
800m site. The video footage from the trawl-mounted camera explained why.
Almost the entire day shift crammed into the STS electronics cupboard to see
the footage and, after the first gasps of 'incroyable!', watched in hushed
awe as a scene rivalling the best parts of the Great Barrier Reef was
revealed. The sea-bed was 100% covered with living material - colourful
branching coralline species and gorgonians forming the major lower storey
structure and large branching sponges the upper storey. Amongst this were
numerous sea-stars, sea-cucumbers, crustacea and fish of types at yet
unseen. After repairing the trawl nets we returned to re-sample the site,
this time being very cautious with the time allowed for the trawl to be on
the bottom, and were rewarded with a relatively small catch but with many
species not previously collected. In marked contrast the communities at
1600m and 2100m were rather sparse with much un-colonised rock and coarse
sediment visible, but again the samples, although small, contained many
species new to us. The deck crew must be congratulated for their skill and
persistence in successfully sampling these very difficult environments,
without which the scientists would have nothing. We have now commenced the
main CASO sampling for the voyage.
Regards, Martin and Sarah.
Saturday 5 January 2008 à 13:50
Algae on ice!
Sophie Mouge. Correspondent aboard the Aurora Australis
Today we’re sailing near a large tabular iceberg about twenty meters high.
Saturday 5 January 2008 à 13:45
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 65°49.519' S
- longitude: 143°00.209’ E
Wind:
- direction: E-SE
- speed: 11 knots
Water temperature: -0.5°C
Air temperature: -0.8°C
Atmospheric pressure: 985 hPa
Relative humidity: 85%
UV-B: 1.8 W/m²
Water depth: 540 meters
Sunrise: above the horizon all day
Saturday 5 January 2008 à 13:40
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 05/01/08
REPORT (SITREP) NO.: 320
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 50S, 142 28E
HEADING: 340T
CURRENT SPEED (KNOTS): 2.5
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 105.9
WEATHER CONDITIONS: Clouds, moderate
visibility, wind decreasing 14 kts from 125T with gusts to 16 kts
AIR
TEMPERATURE: -1
SEA TEMPERATURE: -0.5
SEA CONDITIONS: Moderate seas from SE,
moderate WNW swell 2-3 m
ICE CONDITIONS: Isolated bergs, occasional growlers
and bergy bits, otherwise open water.
REMARKS: We completed sampling the main circuit of eastern CEAMARC benthic
sites yesterday at about 2100 hrs last night and then returned to the
Polynya moorings to move the Pole Compass. The Polyna moorings are measuring
the speed and direction of water currents through the water column using
Acoustic Doppler Current Profilers (ADCP), but at this distance from the
South Magnetic Pole (only about 135 miles WNW of the moorings) normal
compasses are not accurate. The Pole Compass is designed to give accurate
readings even when very close to the magnetic pole and will be positioned
alongside each of the ADCP Polynya moorings for a few days in order to allow
correction of the data from their simpler onboard compasses. The Pole
Compass was redeployed by about 0500 this morning and then CEAMARC sampling
resumed with the first of four sites (400m, 800m, 1600m and 2400m) in a
transect over the edge of the shelf break.
Regards, Martin and Sarah.
Friday 4 January 2008 à 13:11
Antarctic biodiversity inventory: for what?
Sophie Mouge. Correspondent aboard the Aurora Australis
The return of good weather means we can enjoy a fabulous sunset on the horizon of Antarctic sea early this morning, around one o’clock. Once again, our star never left us. It stayed essentially at the same height for three hours.
Friday 4 January 2008 à 13:01
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 66°19.089' S
- longitude: 143°37.275’ E
Wind:
- direction: SE
- speed: 30 knots
Water temperature: -0.6°C
Air temperature: -4°C and -25°C in the wind
Atmospheric pressure: 972 hPa
Relative humidity: 80%
UV-B: 4 W/m²
Water depth: 580 meters
Sunrise: above the horizon all day
Friday 4 January 2008 à 13:00
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 04/01/08
REPORT (SITREP) NO.: 319
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 19S, 143 59E
HEADING: 140T
CURRENT SPEED (KNOTS): 2.5
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 94.6
WEATHER CONDITIONS: Overcast, low grey clouds,
visibility good, wind 34 kts from 149T with gusts to 36 kts
AIR TEMPERATURE:
-4
SEA TEMPERATURE: -0.6
SEA CONDITIONS: Moderate to rough seas and moderate
SE'ly swell 2-3 m ICE
CONDITIONS: Isolated bergs, open water.
REMARKS: Yesterday's blue skies and calm seas were a great contrast to the
stormy weather that began the New Year. We took advantage of the opportunity
and completed 6 stations in the last 2 shift, with the night shift putting
in a particularly strong effort to do nearly 4 complete stations. This
afternoon the strong winds are returning as predicted and may force another
halt to sampling in the next few hours. We are approaching the end of this
stage of the CEAMARC sampling and when conditions allow we will return to
the Polynya moorings to move the Pole Compass. The big isopods, amphipods
and sea-spiders of the past few days were put firmly in their place last
night by the arrival of the Big Polychaete. This magnificent bristle-worm (a
polynoid or scale-worm) was about 9 inches (230 mm) long, 3.5 inches (90 mm)
across, with scales more than 1 inch (24 mm) in diameter and weighed about
330 gm - at just three to the kilo this is by far the largest polychaete
seen by any of the benthic ecologists on board. We have since captured video
imagery of these monsters scurrying along the sea-bed as the trawl
approaches. To top it off, the bristle-worms arrived complete with their
own over-size parasitic nematodes (up to 4 inches long) infesting the space
under the scales.
Regards, Martin and Sarah.
Thursday 3 January 2008 à 15:51
Feather stars among us!
Sophie Mouge. Correspondent aboard the Aurora Australis
The good weather is back!
Thursday 3 January 2008 à 14:40
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 66°34.040' S
- longitude: 144°53.830’ E
Wind:
- direction: S
- speed: 17 knots
Water temperature: -0.7°C
Air temperature: -1.3°C
Atmospheric pressure: 985 hPa
Relative humidity: 70%
UV-B: 8 W/m²
Water depth: 490 meters
Sunrise: above the horizon all day
Thursday 3 January 2008 à 14:10
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 03/01/08
REPORT (SITREP) NO.: 318
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 34S, 144 41E
HEADING: 154T
CURRENT SPEED (KNOTS): 2.5
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 97.3
WEATHER CONDITIONS: Mostly fine and clear with
some cloud, visibility good, wind 17 kts from 185T with gusts to 19 kts
AIR
TEMPERATURE: -1
SEA TEMPERATURE: -0.7
SEA CONDITIONS: Moderate sea,
southerly swell 2 m ICE
CONDITIONS: Isolated bergs, open water.
REMARKS:
After riding out 40 to 50 knot winds for the first day and a half of the New
Year, conditions had abated sufficiently by 1600 hrs yesterday to allow
sampling to re-commence. However, the lull only lasted for about 6 hours
before winds were again gusting to 50 knots and sampling halted. After a
further 8 hour break, sampling re-commenced at about 0500 hrs this morning
and the day shift woke to sunny conditions and light winds. Overall
impressions of the sea-bed invertebrate communities are that the diversity
and species composition on the Adelie Bank seems roughly equivalent to that
known from at Dumont D'Urville at shallower depths (40-200m), but tends to
decrease in Commonwealth Bay, possibly because of increased iceberg
scouring. Two stations (38 & 36) show strikingly different benthic
communities compared to surrounding stations, with many anemones,
synascidians and serolid isopods. These stations are situated well beneath
the action of icebergs at the bottom of the Georges V Basin where water
conditions may play a role in shaping very different assemblages. The
multi-beam data, previously collected in this area by the US research vessel
the Nathaniel Palmer, provides a very detailed picture of the sea-bed
including tracks of past ice-berg scouring. For those sites where it is
available, it is proving invaluable for interpreting the relationship
between the living communities and the physical environment of the sea-bed.
A multi-beam capability must be considered as an essential element of a
modern program of benthic biodiversity research.
Regards, Martin and Sarah.
Wednesday 2 January 2008 à 14:18
Eelpout from every angle
Sophie Mouge. Correspondent aboard the Aurora Australis
The wind is blowing hard and keeping us from trawling. It is better to wait for it to stabilize at 35 knots or less to continuing collecting.
Wednesday 2 January 2008 à 14:12
Data for the Aurora Australis at 12h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 66°55.540' S
- longitude: 144°24.466’ E
Wind:
- direction: S-SE
- speed: 40 knots
Water temperature: -0.7°C
Air temperature: -0.5°C
Atmospheric pressure: 961 hPa
Relative humidity: 89 %
UV-B: 3 W/m²
Water depth: 850 meters
Sunrise: above the horizon all day
Wednesday 2 January 2008 à 13:48
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 02/01/08
REPORT (SITREP) NO.: 317
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 53, 144 54
HEADING: 165T
CURRENT SPEED (KNOTS): 3
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 65
WEATHER CONDITIONS: Overcast, very low cloud,
distant haze, occasional sleet, visibility poor, wind 30 kts from 145T with
gusts to 40 kts
AIR TEMPERATURE: -1
SEA TEMPERATURE: -1
SEA CONDITIONS:
Moderate to rough seas, moderate swell 3-4 m
ICE CONDITIONS: Isolated bergs,
open water.
REMARKS: Last night we continued to ride out the weather. The wind has now
dropped slightly and we are heading back to site 59 to assess whether
trawling is possible, if not we will attempt CTD sampling until conditions
improve. So far, we have caught at least 38 fish species, including 32
Notothenioids, 2 or more Liparids and 4 Zoarcids. The number of species
continues to increase every day. Interestingly, many species previously
recorded to be common in the depth range 0 - 200 m along the Terre Adelie
coast (Trematomus newnesi, Notothenia coriiceps, T. bernacchi, T. hansoni,
Pagothenia borchgrevinki, Gymnodraco acuticeps) are rare or absent in our
catches. The exceptions are two species, the icefish (Chionodraco hamatus)
and the pelagic species, Pleuragramma antarcticum, which were previously
found to be common in the shallow coastal areas and are also common at our
sites. The latter dominates almost all catches in a range of sizes from
small fingerlings to large size adults. Most species caught since the
beginning of the voyage are not new to science, but previously had not been
recorded in this sector of the Eastern Antarctic continental shelf. The
catches are highly diverse but it is too early to say whether diversity is
linked to seabed type or to particular types of benthic assemblage. We have
collected many fingerlings and post-larval fish from the canyons, suggesting
that these steep and rugged areas may play a role as nursery grounds for
some species, particularly channichthyids. We have not yet caught any skate
although they are known from the area off Dumont D'Urville and have been
observed in our videos. They are probably escaping in front of the trawl.
Regards, Martin and Sarah.
Tuesday 1 January 2008 à 13:55
Two New Year’s Eves are better than one!
Sophie Mouge. Correspondent aboard the Aurora Australis
Monday, December 31, 22h : The day shift stops work, Martin has given us two hours off!!!
Tuesday 1 January 2008 à 13:52
Data for the Aurora Australis at 16h30
Sophie Mouge. Correspondent aboard the Aurora Australis
Position of the icebreaker:
- latitude: 66°58.210' S
- longitude: 144°44.466’ E
Wind:
- direction: SE
- speed: 45 knots
Water temperature: -1.5°C
Air temperature: -1.7°C
Atmospheric pressure: 960 hPa
Relative humidity: 99.5 % It’s snowing!
UV-B: 1.1 W/m²
Water depth: 350 meters
Sunrise: above the horizon all day
Tuesday 1 January 2008 à 13:51
Position of Aurora Australis
Sophie Mouge. Correspondent aboard the Aurora Australis
FROM: Martin Riddle
DATE: 01/01/08
REPORT (SITREP) NO.: 316
UNIVERSAL TIME: 0100
LOCAL (SHIP) TIME: 1200
AUSTRALIAN EASTERN STANDARD TIME: 1200
POSITION: -66 51.0, 144 33.2
HEADING: 148T
CURRENT SPEED (KNOTS): 2.5
DISTANCE TO NEXT WAYPOINT (NAUTICAL MILES): N/A
DISTANCE COVERED LAST 24
HOURS (NAUTICAL MILES): 68.9
WEATHER CONDITIONS: Overcast, very low cloud,
blowing snow and sleet, visibility poor, wind 40 kts from 155T with gusts to
50 kts
AIR TEMPERATURE: -1.8
SEA TEMPERATURE: -0.7
SEA CONDITIONS: 4-6 m SE
sea, with heavy swell
ICE CONDITIONS: None visible.
REMARKS: We are currently hove to as we ride out the weather. New and
interesting animals continue to appear in our trawl samples. So far we have
collected about 10 species of the worm-like, shell-less molluscs,
(Aplacophora) and yesterday we found a parasitic mollusc (family Eulimidae)
on a sea-cucumber (holothurian). Some of the Aplacophora and the Eulimid may
well be new records for Antarctica, although without reference to the
scientific literature we are not yet able to make that claim with
confidence. Among the highlights of the video captured by the trawl-mounted
camera is the footage of a surprised-looking pelagic octopus sitting on the
sea-bed in the split second before it was scooped up by the trawl. New Year
on the ship is of course a special occasion and last night the day shift
celebrated it on Tasmanian/ship's time with a masked ball. Now the night
shift are celebrating the GMT New Year. The creativity of those on board
came to the fore in the lead up to the New Year as many clever costumes were
improvised from the limited materials at hand.
Regards, Martin and Sarah.
