15 – 26 Feb Following our ROV dive in the Antarctic Sound, we headed
around the Trinity Peninsula into the Bransfield Strait (see above map of
the Antarctic Peninsula). Along the way, we dropped another whale bone
lander after many hours of rigging this malodorous free-vehicle package
(rotting whale bones smell very bad!!). Following the bone lander
deployment, there was extensive debate among the scientists on board
concerning where to focus our research efforts on the west side of the
Antarctic Peninsula to optimize the scientific outputs from the remainder
of the cruise. The members of the Marine Ecosystems project urged strongly
to conduct a comparative study of fjord ecosystems differentially affected
by climate warming from north to south along the Antarctic Peninsula,
beginning with Admiralty Bay on King George Island. However, we were
overruled by the chief scientist, who insisted on revisiting former study
sites in Hughes Bay in the Gerlache Strait. The Marine Ecosystems group
made the best of the situation, collecting opportunistic multiple cores,
yoyo camera transects and an otter trawl in Hughes Bay from Feb 15-18. The
seafloor fauna in Hughes Bay was very depauperate, apparently heavily
disturbed by large inputs of glacial till (i.e., sediments) from the
numerous glaciers emptying into the bay. In contrast to the
fjord systems we sampled earlier, this site had very little drift
macroalgae on the seafloor, presumably because the open bay has little
subtidal area to support kelps and other macroalgae.
Glaciers calving icebergs into Hughes Bays. Large volumes of
meltwater and sediments are carried into the bay with these icebergs,
causing massive burial disturbance at the seafloor.
At the end of our stay in Hughes Bay, we went ashore in rubber zodiac boats
to collect kelp (for food-web analyses) and to do a bit of site seeing. We
encountered icebergs seeming designed by Gaudi, gentoo
penguins and a large leopard seal dozing on an ice flow
.
Gentoo penguins on the shoreline of Hughes Bay.
A large leopard seal lazily eyeing us from its napping spot on
an ice floe. I think we look like lunch!
On the night of Feb 18, we transited south to Andvord Bay, the fjord just
south of Cape Renaud (see map). There, we completed the earlier work within initiated in this fascinating fjord, using megacore and Blake trawl samples
to document the remarkably rich fauna in the fjord basins. The trawl
brought up huge numbers of giant polychaete worms. These
worms are four inches long, one inch in diameter and stuffed to the
bursting point with eggs and sperm. The biomass and diversity of these
large worms in Andvord Bay are truly remarkable, indicating the seafloor at
500 m depths in the fjord is receiving much more food than the open
continental shelf at similar depths. Most of the seafloor animals we
re covered were filled with reproductive products and appeared ready to
spawn, suggesting this has been a summer of high productivity. It appears
that the fjords like Andvord Bay, because of their food-rich conditions,
could be providing larvae to seed seafloor populations far beyond the fjord
bounds. Because fjord conditions are being altered by climate warming
(i.e., by increasing glacier melting and glacial sediment loading), the
Andvord seafloor ecosystems are likely to be very climate sensitive, and
may be transitioning to the depauperate conditions we observed in Hughes
Bay. Clearly, the Antarctic Peninsula fjord communities merit much
further to study to elucidate their patterns of causes of high
biodiversity, and the sensitivity of these unusually rich communities to
climate warming.
Sausage sized (4-inch long) polychaete worm from the floor of
Andvord Bay. This ampharetid worm is white because it is bulging with
sperm ready to be released into the water column during mass spawning.
Our final day in Andvord Bay was punctuated by a helicopter ride for the
benthic ecologists (Laura, Craig and David). We flew from the ship to the
desolate top of the Antarctic Peninsula, getting a view of the massive ice
fields straddling the Peninsula. As we descended down a
glacier back to the ship, the views were astounding, leaving impressions of
stark beauty that we will retain for a life time.
The ice sheet atop the Antarctic Peninsula. This sheet extends
unbroken for 1000 miles along the Peninsula to the main part of the
Antarctic Continent.
View from the Helicopter as we fly down from the top of the
Antarctic Peninsula into Andvord Bay.
On 24 Feb we completed our seafloor ecosystem studies along the west
Antarctic Peninsula by deploying another whale bone lander south of Anvers
Island, and then conducting an ROV dive in the Palmer Deep, a 1440 m deep
basin off the southeast tip of Anvers Island. To our surprise, we found a
large number of king crabs in the basin at depths below 1000 m, indicating
that these invasive marauders have already penetrated deep onto the
Antarctic shelf. As mentioned earlier, king crabs have been
excluded from Antarctic ecosystems for possibly millions of years due to
very low water temperatures on the Antarctic shelf. Climate warming in
this region apparently is allowing these species to move shallower,
threatening the vulnerable unique Antarctic seafloor communities. Where we
found abundant crabs on the Palmer deep floor, we only found sea anemonies,
suggesting that the brittle stars and crinoids had been consumed by the
voracious, skeleton crushing crabs. This discovery of crabs in the Palmer
deep is a sobering reminder of the vulnerability of Antarctic marine
ecosystems to climate change.
Marauding king crabs marching across the floor of the Palmer
Deep. These crabs are bad news for the endemic Antarctic benthic fauna!
After spending 25 Feb packing and stowing gear in the hold and on the upper
decks of the NP Palmer, we are now heading north across the Drake Passage
towards Punta Arenas (to be reached in four days time). The forecasts are
for rough weather in the Drake -- nothing unusual in this part of the
ocean! Our last views of the ice bound continent and islands were of
Smith Island in the Bransfield Strait in the wee hours of the 26th. While
we are all eager to get home after two long months at sea, we will miss the
scenery and ecosystems of Antarctica!
Thursday, March 4, 2010
Non-programmed camping in James Ross Island
10 - 14 Feb With heavy hearts we have headed northward from Lockyer Station
and out through the Antarctic Sound to the west side of the Antarctic
Peninsula. Unusually heavy sea ice, including floes (or floating ice slabs)
several years old and meters thick have forced us to abandon our plan to
work in the Larsen B area. Although our vessel, the NB Palmer, is an
icebreaker, it cannot safely smash its way through multiyear sea ice
because of high pressure ridges (compressed areas of sea ice 3-4 meters
high). It is clearly unsafe to linger longer on the eastern side of the
Antarctic Peninsula this high ice year, and even our offshore oceanographic
sites are now covered solidly with the pack ice.
Satellite image showing heavy sea-ice cover throughout our desired study area in the Larsen B vicinity (dashed circle). Flat whit areas are sea ice and ice shelves; ruffled areas throwing shadow are clouds. In most years, the circled area is clear of sea ice by the end of January. The heavy sea conditions this year illustrate the high interannual variability in weather conditions in the Antarctic – even though climate warming continues at a very fast rate in this region, during some years, sea ice may still persist throughout the summer due to stochastic weather processes.
Before leaving Lockyer Station, we had a bit of a scare, and a reminder that the Antarctic is still a remote and potentially dangerous environment. Two of our party, a geologist and writer for National Geographic, were flown by helicopter to a site on the Antarctic Peninsula 25 miles away to collect glacial erratics (rocks dropped by glaciers far from their site of origin). As they were working, the weather began to close in so they helicopter flew out the pick them up and return them to the ship. During the return flight (only about 15 minutes), the weather closed in even further, and whiteout conditions forced the helicopter, with three aboard, to land on a beach on James Ross Island only 6 miles from the ship. A snow storm ensued for the next three days, grounding the scientist, writer and helicopter pilot in two small tents for three days. The helicopters always travel with emergency rations for 6 days, sleeping bag s and tents, so the stranded party was is in no immediate danger. However, it was sobering to realize that while they were only 6 miles from us, there was nothing we or anyone else on earth could do for them until the snow storm abated. After 3 days, we finally had a patch of blue sky in which to recover our now smelly shore party. They had spent their time digging a latrine, building snow walls to protect the tents from the 30 inches of snow fall, and reading and dozing in their sleeping bags. The National Geographic writer now has quite a story to tell about forced camping in the Antarctic wilderness, an experience somewhat reminiscent of the stranding of Shackleton’s shore party on Elephant Island, 180 miles north of here.
The snow storm that stranded three of our expedition members on James Ross Island for three days.
Following recovery of our wayward three, the NB Palmer crashed northward through very thick sea ice, making only 2-4 knots for 26 hours. As we entered the Antarctic Sound, the strait between the Weddell and Scotia Seas at the north end of the Antarctic Peninsula, the sea ice thinned and we were able to make much better time. By evening of the 13th we were in position for an ROV dive on a recently discovered submerged volcano in the Antarctic Sound, to search for hydrothermal vents to provide study organisms for David Honig and Mike McCormick. The ROV dive found no vents, but did reveal dense communities of sponges, crinoids (see lilies), brittle stars and other suspension feeders characteristic of the Antarctic seafloor. It is thought that such communities can thrive in the Antarctic only because large crushing predators, such as king crabs and bottom feeding sharks, are excluded by the very cold Antarctic waters (below 0 centigrade). Such communities of exposed suspension feeders occurred worldwide in the ancient ocean, but apparently were eliminated with the evolution of large crabs and bottom-feeding sharks. The lack of these large, skeleton-crushing (or duraphagous) predators in the Antarctic has allowed the radiation of a diverse assemblage of suspension feeders unique to Antarctic waters. As climate change brings warmer waters to the Antarctic, skeleton-crushing predators, especially king crabs, threaten to invade shallow waters around the Antarctic Peninsula, potentially leading to the extinction of many unique Antarctic species. During the dive we also observed giant “barrel” sea anemones that apparently roll along the seafloor without a permanent attachment. This may be an adaptation to utilize habitats newly exposed by the bulldozing of the seafloor by grounding icebergs, a major source of disturbance for seafloor habitats at depths less than 300 m in Antarctica.
The NB Palmer breaking its way though multi-year sea ice south of the Antarctic Sound.
A dense assemblage of suspension feeding sea lilies (crinoids, plumose yellow animals), brittle stars, sponges (white blobs and shapes), and octocorals (pink trees) on the seafloor at 500 m depths on the submerged volcano in the Antarctic Sound. This is classic, high-biomass, exposed Antarctic benthic assemblage is likely to be very susceptible to predation from invading king crabs.
Barrell anemone approximately 30 cm (12 inches) long rolling along the seafloor on the Antarctic Sound submerged volcano.
Satellite image showing heavy sea-ice cover throughout our desired study area in the Larsen B vicinity (dashed circle). Flat whit areas are sea ice and ice shelves; ruffled areas throwing shadow are clouds. In most years, the circled area is clear of sea ice by the end of January. The heavy sea conditions this year illustrate the high interannual variability in weather conditions in the Antarctic – even though climate warming continues at a very fast rate in this region, during some years, sea ice may still persist throughout the summer due to stochastic weather processes.
Before leaving Lockyer Station, we had a bit of a scare, and a reminder that the Antarctic is still a remote and potentially dangerous environment. Two of our party, a geologist and writer for National Geographic, were flown by helicopter to a site on the Antarctic Peninsula 25 miles away to collect glacial erratics (rocks dropped by glaciers far from their site of origin). As they were working, the weather began to close in so they helicopter flew out the pick them up and return them to the ship. During the return flight (only about 15 minutes), the weather closed in even further, and whiteout conditions forced the helicopter, with three aboard, to land on a beach on James Ross Island only 6 miles from the ship. A snow storm ensued for the next three days, grounding the scientist, writer and helicopter pilot in two small tents for three days. The helicopters always travel with emergency rations for 6 days, sleeping bag s and tents, so the stranded party was is in no immediate danger. However, it was sobering to realize that while they were only 6 miles from us, there was nothing we or anyone else on earth could do for them until the snow storm abated. After 3 days, we finally had a patch of blue sky in which to recover our now smelly shore party. They had spent their time digging a latrine, building snow walls to protect the tents from the 30 inches of snow fall, and reading and dozing in their sleeping bags. The National Geographic writer now has quite a story to tell about forced camping in the Antarctic wilderness, an experience somewhat reminiscent of the stranding of Shackleton’s shore party on Elephant Island, 180 miles north of here.
The snow storm that stranded three of our expedition members on James Ross Island for three days.
Following recovery of our wayward three, the NB Palmer crashed northward through very thick sea ice, making only 2-4 knots for 26 hours. As we entered the Antarctic Sound, the strait between the Weddell and Scotia Seas at the north end of the Antarctic Peninsula, the sea ice thinned and we were able to make much better time. By evening of the 13th we were in position for an ROV dive on a recently discovered submerged volcano in the Antarctic Sound, to search for hydrothermal vents to provide study organisms for David Honig and Mike McCormick. The ROV dive found no vents, but did reveal dense communities of sponges, crinoids (see lilies), brittle stars and other suspension feeders characteristic of the Antarctic seafloor. It is thought that such communities can thrive in the Antarctic only because large crushing predators, such as king crabs and bottom feeding sharks, are excluded by the very cold Antarctic waters (below 0 centigrade). Such communities of exposed suspension feeders occurred worldwide in the ancient ocean, but apparently were eliminated with the evolution of large crabs and bottom-feeding sharks. The lack of these large, skeleton-crushing (or duraphagous) predators in the Antarctic has allowed the radiation of a diverse assemblage of suspension feeders unique to Antarctic waters. As climate change brings warmer waters to the Antarctic, skeleton-crushing predators, especially king crabs, threaten to invade shallow waters around the Antarctic Peninsula, potentially leading to the extinction of many unique Antarctic species. During the dive we also observed giant “barrel” sea anemones that apparently roll along the seafloor without a permanent attachment. This may be an adaptation to utilize habitats newly exposed by the bulldozing of the seafloor by grounding icebergs, a major source of disturbance for seafloor habitats at depths less than 300 m in Antarctica.
The NB Palmer breaking its way though multi-year sea ice south of the Antarctic Sound.
A dense assemblage of suspension feeding sea lilies (crinoids, plumose yellow animals), brittle stars, sponges (white blobs and shapes), and octocorals (pink trees) on the seafloor at 500 m depths on the submerged volcano in the Antarctic Sound. This is classic, high-biomass, exposed Antarctic benthic assemblage is likely to be very susceptible to predation from invading king crabs.
Barrell anemone approximately 30 cm (12 inches) long rolling along the seafloor on the Antarctic Sound submerged volcano.
Monday, March 1, 2010
Lockyer Station
3 – 9 Feb The last few days of have been a flurry of oceanographic
sampling activity, during which we have collected two kasten cores, 6
megacores, one Blake trawl, numerous CTD’s, and conducted 6 yoyo camera
transects. This sampling is to characterize our first oceanography station
near Lockyer Island (dubbed “Lockyer Station”) to provide insights into
seafloor and water-column ecological processes and community structure on
the inner continental shelf site not recently influenced by an Antarctic
ice sheet. The seafloor at Lockyer Station lies 505 m below the sea
surface and is a plain covered with mud intermixed with gravel from iceberg
rafted material. Our yoyo camera transects and trawl sample reveal a
relatively rich community of megafauna (animals large enough to be
identified in photographs), including large “sea pigs” (sea cucumbers
in the genus Protelpidia, picture 38), very large brittles stars
(Ophiostarte gigas, picture 39), and an occasional giant basket glass
sponge with crinoids (sea lilies, picture 40). Many of the megafauna are
unusually large, including the 20 cm long sea pigs and meter high basket
sponges, suggesting that this is a stable sedimentary environment (low
flow, little disturbance ice bergs, and slow sediment accumulation). The
station looks very much like our continental shelf stations at similar
depths on the other side of the Antarctic Peninsula, west of Anvers Island.
Our trawl sample also recovered a diversity of large benthic (seafloor
species) including a large icefish (picture 41) . These fish are unique to
Antarctica and have no hemoglobin in their blood; oxygen concentrations are
high enough in the cold Antarctic waters that these sluggish fish do not
need hemoglobin in their blood to carry oxygen. Their gills and blood are
translucent white.
Large sea pig 20 cm (8 inches) long. This animal is a “deposit feeder" and uses that tentactles at left to ingest mud particles. It then digests off the organic matter for food. This is the most common feeding mode on Earth!
The large, mucus cover brittle star Ophiostarte gigas. This is a predator that feeds on other brittle stars, polychaete worms, and crustaceans.
A giant filter feeding basket sponge about 1 meter tall and half a meter wide (this is a downward view from the Yoyo Camera). Clinging to the sides of the sponge are yellow crinoids, or sea lilies. Both the sponge and crinoids are suspension feeders that removed food particles as they drift by in the water column.
An ice fish caught in the trawl. These are called ice fish because their blood is transparent due to an absence of hemoglobin. Their gills are translucent.
After three grueling 18-hr work days, our intrepid benthic team of Laura, David and Craig (me) are now nearly finished with sampling of the seafloor biota at Station Lockyer. Our samples have been excellent in quality and we are confident we will be able to characterize biodiversity and ecosystem function at this station (including foodweb structure and rates of sediment mixing by mud-eating animals like sea cucumbers). It will provide an excellent baseline to compare to the Larsen B stations recently exposed from beneath ice shelves. Unfortunately, the sea ice is thickening around us and further south in the Larsen B area, so it now seems unlikely that we will be able to get to Larsen B for the rest of the cruise. Time to develop plan B!
Large sea pig 20 cm (8 inches) long. This animal is a “deposit feeder" and uses that tentactles at left to ingest mud particles. It then digests off the organic matter for food. This is the most common feeding mode on Earth!
The large, mucus cover brittle star Ophiostarte gigas. This is a predator that feeds on other brittle stars, polychaete worms, and crustaceans.
A giant filter feeding basket sponge about 1 meter tall and half a meter wide (this is a downward view from the Yoyo Camera). Clinging to the sides of the sponge are yellow crinoids, or sea lilies. Both the sponge and crinoids are suspension feeders that removed food particles as they drift by in the water column.
An ice fish caught in the trawl. These are called ice fish because their blood is transparent due to an absence of hemoglobin. Their gills are translucent.
After three grueling 18-hr work days, our intrepid benthic team of Laura, David and Craig (me) are now nearly finished with sampling of the seafloor biota at Station Lockyer. Our samples have been excellent in quality and we are confident we will be able to characterize biodiversity and ecosystem function at this station (including foodweb structure and rates of sediment mixing by mud-eating animals like sea cucumbers). It will provide an excellent baseline to compare to the Larsen B stations recently exposed from beneath ice shelves. Unfortunately, the sea ice is thickening around us and further south in the Larsen B area, so it now seems unlikely that we will be able to get to Larsen B for the rest of the cruise. Time to develop plan B!
Hill Island
30 Jan – 2 Feb We are now a halted in the sea ice a few miles west of
Snow Hill Island, unable to break our way any close than 60 miles to the
entrance of the Larsen B region, around the tip of Robertson Island
(map below). Quite appropriately, we can see Cape Longing in the
distance, reflecting our desire to get further south into our primary study
area. Our satellite images of sea ice indicate that the leads are closing
in the Larsen B area, reducing the changes of getting there. We are within
helicopter range of several or our terrestrial sites for GPS stations that
will evaluate the rebound, or rise, of land masses as a result of the
breakup of the Larsen B shelf; a vast weight of ice has been lifted from
the the coast in this region, and the Antarctic peninsula is likely to be
rising at a few millimeters a year as a consequence. Thus, the terrestrial
components of our program may not be set back too heavily from lack of ship
access to the Larsen B region.
Map of East Antarctic Peninsula including Larsen B Area, and showing Lockyer Island Station location near Snow Hill Island.
The oceanographers on board the vessel have discussed how to modify our sampling program to best advance our goals of studying the effects of ice-shelf loss on Antarctic marine ecosystems, while working in waters in which sea-ice conditions will allow the ship to work. A number of smaller ice shelves have collapsed on this eastern side of the Antarctic Peninsula in the last few decades, including one covering the southern Gustav Channel (see map). We now plan to sample the Gustav Channel as a post-ice shelf system (with ice shelf loss in about 1992), and then to sample the mid- and outer-continental shelf stations east of James Ross Island, to provide a comparison with the open sea-ice zone. We will also sample an inner shelf site just west of Snow Hill Island, very close to our current location. These latter three sites will provide a necessary context to evaluate colonization patterns in the Gustav Channel, and in the Larsen B area, when we finally are able to get south of Robertson Island (most likely not until 2012, during our next LARISSA cruise). Thus, even though we are currently barred from the Larsen B area by sea ice, we will be able to conduct ecosystem studies on this cruise that advance or understanding of the effects of rapid climate warming and loss of ice shelves on Antarctic marine ecosystems. Now that we have a workable plan, we are eager to press forward with our sampling!
Map of East Antarctic Peninsula including Larsen B Area, and showing Lockyer Island Station location near Snow Hill Island.
The oceanographers on board the vessel have discussed how to modify our sampling program to best advance our goals of studying the effects of ice-shelf loss on Antarctic marine ecosystems, while working in waters in which sea-ice conditions will allow the ship to work. A number of smaller ice shelves have collapsed on this eastern side of the Antarctic Peninsula in the last few decades, including one covering the southern Gustav Channel (see map). We now plan to sample the Gustav Channel as a post-ice shelf system (with ice shelf loss in about 1992), and then to sample the mid- and outer-continental shelf stations east of James Ross Island, to provide a comparison with the open sea-ice zone. We will also sample an inner shelf site just west of Snow Hill Island, very close to our current location. These latter three sites will provide a necessary context to evaluate colonization patterns in the Gustav Channel, and in the Larsen B area, when we finally are able to get south of Robertson Island (most likely not until 2012, during our next LARISSA cruise). Thus, even though we are currently barred from the Larsen B area by sea ice, we will be able to conduct ecosystem studies on this cruise that advance or understanding of the effects of rapid climate warming and loss of ice shelves on Antarctic marine ecosystems. Now that we have a workable plan, we are eager to press forward with our sampling!
Sunday, January 31, 2010
Rothera British station
We were first treated to a tour of the base and a walk around Rothera
Point. The base itself consists of a large science laboratory called the
Bonner Lab which also houses the dive locker, Admiralty House which is used
for accommodation, the new and old Bransfield buildings and Fuchs House,
where all field equipment and recreational skiing/snowboarding gear is kept
. The new Bransfield building was opened in 2007 and houses all
the communal space at Rothera, including the mess (or dining room),
library, bar and the base shop, which sells clothing, postcards and other
souvenirs. The view from the mess has got to be one of the best dining hall
views in the Southern Ocean! Rothera also has its own 1-km
runway, which is utilized by two types of BAS aircraft, the DASH-7 and the
Twin Otter. These aircraft fly people in and out of Rothera from the
Falklands (DASH-7), and are also used to deploy field parties onto the
ice-sheet and to remote field stations further south (Twin Otters). An
American Twin Otter is being used by our glaciologists to access their
remote field sites from Rothera’s airstrip.
Rothera Station at sunset by Greg Balco.
The new Bransfield building opened in 2007 looking out over South Cove.
Walking around the point gave everyone a great opportunity to stretch their legs, relax and appreciate the scenery and wildlife local to Rothera. This included Weddell seals and Adelie penguins. We also paid a visit to the base shop to buy our own little memento of the trip and postcards to send to family and friends.
Adelie penguins with chicks. Many have fluffy grey twins!
My evening was spent reminiscing with old Rothera friends and socializing with the new ones I have made onboard the NB Palmer. After several games of pool, darts and a eight-a-side football (soccer) game by the soccer buffs, it was time to return to the ship and for me to say goodbye to Rothera for a second time. A great time was had by everyone and all onboard were grateful to the Rotherians for their warm welcome and their hospitality.
Visiting Rothera, for me at least, was almost like coming home. Every thing and everyone felt very familiar, and apart from the new Bransfield building, the base itself had not changed. It almost felt like I had never left!
The Nathaniel B Palmer tied up at the pier at Rothera Station, with Laura in the foreground atop Monument Hill.
Rothera Station at sunset by Greg Balco.
The new Bransfield building opened in 2007 looking out over South Cove.
Walking around the point gave everyone a great opportunity to stretch their legs, relax and appreciate the scenery and wildlife local to Rothera. This included Weddell seals and Adelie penguins. We also paid a visit to the base shop to buy our own little memento of the trip and postcards to send to family and friends.
Adelie penguins with chicks. Many have fluffy grey twins!
My evening was spent reminiscing with old Rothera friends and socializing with the new ones I have made onboard the NB Palmer. After several games of pool, darts and a eight-a-side football (soccer) game by the soccer buffs, it was time to return to the ship and for me to say goodbye to Rothera for a second time. A great time was had by everyone and all onboard were grateful to the Rotherians for their warm welcome and their hospitality.
Visiting Rothera, for me at least, was almost like coming home. Every thing and everyone felt very familiar, and apart from the new Bransfield building, the base itself had not changed. It almost felt like I had never left!
The Nathaniel B Palmer tied up at the pier at Rothera Station, with Laura in the foreground atop Monument Hill.
Sailing back to the Weddell Sea
21-29 January. After nearly one month at sea, we are finally heading for our
primary study sites on the east side of the Antarctic Peninsula in the
Weddell Sea (near Cape Disappointment; see the map a few posts ago). Until now we have been
locked out of the Weddell Sea by an unseasonably high concentration of sea
ice, forced to conduct helicopter operations from the west side, trying to
fly over the mountainous peninsula. On all but three days,
the clouds have been so low that helo operations were cancelled leaving us
to study fjords on the west side of the Peninsula. While fascinating,
these fjords are not the focus of our LARISSA Project, designed to assess
the ecosystem impacts of the climate-change induced melting of the Larsen B
Ice Shelf. Thus, while we have been surrounded by beautiful scenery,
enhanced by the passage of a 65-foot French yacht (picture below), our spirits
have been low: we have been planning for years to conduct this exciting
climate-change research in the Weddell Sea and we are unlikely to get a
second chance!
One of our helicopters flying from the ship over the mountains of the Antarctic Peninsula at Barilari Bay. These rides can be a thrill a minute in the downdrafts of the catabatic winds coming down off the mountains!
65-foot French yacht we met cruising in Antartica. She is dwarfed by the icebergs. On a day like this, the Antarctica Peninsula scenery is otherworldly. However, when the winds pick up, every bergie bit (small chunks of glacial ice) is a potential reef!
At long last, two developments have brightened our prospects. The first was the recognition that much of the glaciology work atop the Peninsula could be conducted by Twin Otter (or ski plane) flights from the British Base at Rothera, on west side of the Peninsula. This allowed us to drop our 5 glaciology colleagues off at Rothera, freeing the ship to head back for the Weddell without compromising the terrestrial components of LARISSA (even if the ship gets stuck in the ice!). Our trip south to Rothera passed by whimsically named islets (including Beer Island and Hennessey Island, to torment our teetotalling ship!) and through narrow passages, included the Tickle Channel (picture below), which fortunately failed to tickle our ship’s bottom. At Rothera Base we received a warm welcome from our British colleagues as well as the wildlife. At the end of our 12-hour visit, we had an international soccer match (in which the Brits exhibited their World-Cup prowess) followed by a party in Rothera’s lounge which ended as midnight tolled and our ship departed Rothera Harbor (with moons up)!
Early morning passage through the Tickle Channel on the way south to Rothera Base. Seals and penguins dot the bergie bits in the channel. The icebergs tickle the sides of the ship.
The residents of Rothera Base are so friendly that even the crabeater seals will offer a kiss! "Don't show my wife!!"
The second positive development for LARISSA came from satellite images of the Weddell Sea -- the ice is starting to break out! This has been precipitated by long-awaited southwesterly winds combined with warming summer temperatures in the Weddell Sea. We are now racing around the tip of the Antarctic Peninsula once again, hoping to find, at most, broken ice flows and leads (i.e., channels) through which the ship can maneuver. If all goes well, we still may have time to complete our oceanographic program, exploring animal colonization and cold-seep biotas at the seafloor under the recently broken out Larsen B Ice Shelf.
Because of our scientific difficulties, the cruise thus far has been bittersweet. Normally, after a month at sea, one falls into a rhythm characteristic of the ship’s routine, the scientific sampling program, and the unique suite of shipboard companions. This cruise has remained rythmless through forced changes in plans and shipboard companions on nearly a daily basis. One clear message is that research expeditions to Antarctica must be, if anything, flexible and opportunistic. Modern oceanographic technology is still no match for a frozen Southern Ocean. However, as the sea ice wanes we now all hope to address our core oceanography program, and to begin sampling intensively around the clock. Despite the ice delays, the sea ice will become our friend once on we reach our oceanographic stations because it calms the seas, allowing our sampling devices (such as box cores, megacores and yoyo cameras (picture below) to work at high efficiency.
We have just entered the fast ice – a featureless plain stretching white to the horizon. The scraping and growling begins anew! We hope Poseidon allows us to pass through the sea ice to our stations!!
The intrepid Yoyo Camera being lowered into the ocean in Barilari Bay. This camera is raised and lowered (or "yoyo-ed") near the seafloor, allowing the lead weight on the end of the line to trip the camera. In this way, we get about 100 high quality pictures of the seafloor and its denizens over a distance of about 1 km (see picture a few posts earlier).
One of our helicopters flying from the ship over the mountains of the Antarctic Peninsula at Barilari Bay. These rides can be a thrill a minute in the downdrafts of the catabatic winds coming down off the mountains!
65-foot French yacht we met cruising in Antartica. She is dwarfed by the icebergs. On a day like this, the Antarctica Peninsula scenery is otherworldly. However, when the winds pick up, every bergie bit (small chunks of glacial ice) is a potential reef!
At long last, two developments have brightened our prospects. The first was the recognition that much of the glaciology work atop the Peninsula could be conducted by Twin Otter (or ski plane) flights from the British Base at Rothera, on west side of the Peninsula. This allowed us to drop our 5 glaciology colleagues off at Rothera, freeing the ship to head back for the Weddell without compromising the terrestrial components of LARISSA (even if the ship gets stuck in the ice!). Our trip south to Rothera passed by whimsically named islets (including Beer Island and Hennessey Island, to torment our teetotalling ship!) and through narrow passages, included the Tickle Channel (picture below), which fortunately failed to tickle our ship’s bottom. At Rothera Base we received a warm welcome from our British colleagues as well as the wildlife. At the end of our 12-hour visit, we had an international soccer match (in which the Brits exhibited their World-Cup prowess) followed by a party in Rothera’s lounge which ended as midnight tolled and our ship departed Rothera Harbor (with moons up)!
Early morning passage through the Tickle Channel on the way south to Rothera Base. Seals and penguins dot the bergie bits in the channel. The icebergs tickle the sides of the ship.
The residents of Rothera Base are so friendly that even the crabeater seals will offer a kiss! "Don't show my wife!!"
The second positive development for LARISSA came from satellite images of the Weddell Sea -- the ice is starting to break out! This has been precipitated by long-awaited southwesterly winds combined with warming summer temperatures in the Weddell Sea. We are now racing around the tip of the Antarctic Peninsula once again, hoping to find, at most, broken ice flows and leads (i.e., channels) through which the ship can maneuver. If all goes well, we still may have time to complete our oceanographic program, exploring animal colonization and cold-seep biotas at the seafloor under the recently broken out Larsen B Ice Shelf.
Because of our scientific difficulties, the cruise thus far has been bittersweet. Normally, after a month at sea, one falls into a rhythm characteristic of the ship’s routine, the scientific sampling program, and the unique suite of shipboard companions. This cruise has remained rythmless through forced changes in plans and shipboard companions on nearly a daily basis. One clear message is that research expeditions to Antarctica must be, if anything, flexible and opportunistic. Modern oceanographic technology is still no match for a frozen Southern Ocean. However, as the sea ice wanes we now all hope to address our core oceanography program, and to begin sampling intensively around the clock. Despite the ice delays, the sea ice will become our friend once on we reach our oceanographic stations because it calms the seas, allowing our sampling devices (such as box cores, megacores and yoyo cameras (picture below) to work at high efficiency.
We have just entered the fast ice – a featureless plain stretching white to the horizon. The scraping and growling begins anew! We hope Poseidon allows us to pass through the sea ice to our stations!!
The intrepid Yoyo Camera being lowered into the ocean in Barilari Bay. This camera is raised and lowered (or "yoyo-ed") near the seafloor, allowing the lead weight on the end of the line to trip the camera. In this way, we get about 100 high quality pictures of the seafloor and its denizens over a distance of about 1 km (see picture a few posts earlier).
Sunday, January 24, 2010
Danco Coast Fjords
14-21 January We have spent the past week along the Danco Coast on the west Antarctic Peninsula (64 to 66 degrees south latitude), working in fjords carved by massive glaciers. Our primary LARISSA Project goal here is to hug the coast across the peninsula from our geological and glacial studies sites, hoping to send teams of geologists by helicopter over the mountains to their work areas. This requires clear flying weather simultaneously on both sides of the Peninsula (a 6000 ft mountain range), which occurs infrequently. The weather has been cloudy for the last week, precluding helicopter operations, but allowing us to study the oceanography of the Danco Coast fjords.
The NB Palmer dwarfed by a tidewater glacier calving into Flandres Bay, a fjord on the Danco Coast.
Map of the Antarctica Peninsula, showing the fjords of the Danco and Graham Coasts.
The Fjords of the west Antarctica Peninsula are oceanographically extremely interesting because they contain “tidewater glaciers”, i.e., glaciers calving icebergs directly into the ocean. In addition, the Antarctic Peninsula fjords have only opened relatively recently (in the last few thousand years), i.e., they represent early stages in the transition of fjords from ice-choked polar to ice-free temperate ecosystems. The oceanography and seafloor ecology of of fjords have been intensively studied in Norway, Canada and Alaska, but these are warm fjords compared to the Antarctic Peninsula and contain rapidly melting glaciers or no glaciers at all. The marine ecosystems of the Antarctic Peninsula fjords are likely to be fundamentally different (e.g., they have relatively little input of glacial meltwater and rock flour) and yet they have been little studied. Thus, while waiting to complete our helicopter operations, the oceanographers on board the NB Palmer are conducted studies of the ecology of the Peninsula Fjords.
Massive front of tidewater glaciers emptying into Barilari Bay.
Humpback whales feeding in Flandres Bay, some only meters from the bow of the ship!
Abundant brittle stars, sea spiders, spoon worms, and starfish on 2 square meters of seafloor at a depth of 600 m in Flandres Bay fjord.
After studying two fjords near Anvers Island, we are now heading south to Barilari Bay, a fjord south of Cape Garcia on the Graham Coast. If the weather clears, we hope to send glaciologists on to the top of the Peninsula to emplace GPS units to measure glacial movement. However, since the weather has remained cloudy, preventing helo operations since we arrive on the west side of the Peninsula more than one week ago, we are quite worried that we can complete the helicopter transfers. At least we can explore the ecosystem of another fjord, working with truly breathtaking backdrops.
Conducting a plankton tow from a zodaic inflatable boat with a Flanders Bay glacier and mountains as backdrop.
The NB Palmer dwarfed by a tidewater glacier calving into Flandres Bay, a fjord on the Danco Coast.
Map of the Antarctica Peninsula, showing the fjords of the Danco and Graham Coasts.
The Fjords of the west Antarctica Peninsula are oceanographically extremely interesting because they contain “tidewater glaciers”, i.e., glaciers calving icebergs directly into the ocean. In addition, the Antarctic Peninsula fjords have only opened relatively recently (in the last few thousand years), i.e., they represent early stages in the transition of fjords from ice-choked polar to ice-free temperate ecosystems. The oceanography and seafloor ecology of of fjords have been intensively studied in Norway, Canada and Alaska, but these are warm fjords compared to the Antarctic Peninsula and contain rapidly melting glaciers or no glaciers at all. The marine ecosystems of the Antarctic Peninsula fjords are likely to be fundamentally different (e.g., they have relatively little input of glacial meltwater and rock flour) and yet they have been little studied. Thus, while waiting to complete our helicopter operations, the oceanographers on board the NB Palmer are conducted studies of the ecology of the Peninsula Fjords.
Massive front of tidewater glaciers emptying into Barilari Bay.
Humpback whales feeding in Flandres Bay, some only meters from the bow of the ship!
Abundant brittle stars, sea spiders, spoon worms, and starfish on 2 square meters of seafloor at a depth of 600 m in Flandres Bay fjord.
After studying two fjords near Anvers Island, we are now heading south to Barilari Bay, a fjord south of Cape Garcia on the Graham Coast. If the weather clears, we hope to send glaciologists on to the top of the Peninsula to emplace GPS units to measure glacial movement. However, since the weather has remained cloudy, preventing helo operations since we arrive on the west side of the Peninsula more than one week ago, we are quite worried that we can complete the helicopter transfers. At least we can explore the ecosystem of another fjord, working with truly breathtaking backdrops.
Conducting a plankton tow from a zodaic inflatable boat with a Flanders Bay glacier and mountains as backdrop.
Thursday, January 21, 2010
13 January - This morning saw us progress further through the Gerlache Strait and into a glacial fjord named Flandres Bay. Efforts were made by all involved to ready the helicopters for flight and prepare equipment and supplies for the glaciology field teams. However unfortunately, the weather closed in before flying could start and consequently, both aircraft had to be grounded until the forecast improved. All onboard the ship had their fingers crossed for better weather soon.
Members of the biology team and oceanographic scientists instead busied themselves with the deployment and sampling of the CTD (a device which profiles the conductivity, temperature and depth at several intervals throughout the water column and which collects water samples that will be filtered and analyzed for phytoplankton, productivity and nutrients) at the head of Flandres Bay. We hope to deploy this device multiple times whilst in the bay, and will use data collected from each cast to build a comprehensive picture of what the water column looks like oceanographically and biologically.
Work on and the processing of the whale bone lander, recovered on 8th January off Vega Island was also concluded today. This was a relief for us and for the majority of the people onboard as whale bones are notoriously foul smelling (they produce a rotten egg smell common in anoxic marine environments and processes of decay), and this meant the bones could be packaged up and stored frozen before being deployed again later in our cruise schedule. Several species of worm, including the bone eating worm Osedax sp, were identified on several of the whale vertebrae. Further work will be undertaken on these specimens once we return to the lab in Hawaii, including morphological and molecular taxonomy to evaluate the evolutionary relationships of these worms.
12 January - As the sun rose on the morning of the 12th we continued our journey into open ocean, out of and away from the fast ice that had hampered our progress on the east side of the Peninsula, and bound for the west. From here, the two helicopters we have onboard will transport teams of glaciologists to sites on the Peninsula, where rock geology will be described, ice characteristics measured and the installation of field stations will occur, allowing for long term monitoring of glacial features.
As one of few people who have been lucky enough to visit Antarctica and spend time here working, I (Laura) can honestly say you never tire of the sights and sounds this incredible landscape has to offer. Our journey to the west side of the Peninsula was no exception. I am glad to say our passage was both smooth (for those prone to seasickness amongst us) and idyllic, and provided yet another backdrop of beautiful scenery, during which we were treated to sights of snow-capped mountains, blue open-ocean and floating masses of ice. We made steady progress over the morning passing through the Antarctic Sound, along the coast, and down through the Bransfield Strait into the Gerlache Strait. This area is also renowned for whale-spotting and sure enough several sightings of both Minke whale and Humpback whale were made today close to the ship. These majestic animals are common in these waters, transiting, feeding and using the area as a mating ground. All aboard the ship were happy and excited to welcome our new visitors and were equally anxious for them to stay around long enough to make the most of an amazing photo opportunity.
This side of the Peninsula is characterized by an array of glacial fjord systems and it is from these sheltered inlets that we intend to monitor the weather and co-ordinate helicopter missions when conditions are suitable for flying. Glacial fjords are unique environments influenced greatly by processes of sedimentation, water circulation and glacier retreat which
vary along the length of the fjord system. Consequently, the marine animals living on the sea floor of these areas are of biological interest to scientists. Therefore, in an effort to make the most of our new location and take advantage of a unique opportunity to sample the animals in these fjordic systems the biology team intend to photograph, survey and document
the animals living on the seabed. This will be done using an underwater ‘yoyo’ camera system- a camera which is lowered to the seafloor, and allowed to contact the seabed at which point a contact switch is triggered and a picture is taken. The camera is then brought off the sea bed a couple of meters, whilst the ship moves slowly a long a transect, and lowered again in a ‘yoyo’ like motion until a series of pictures are taken. We will also use a remote operated vehicle (ROV)- a robot on a cable which is piloted by an operator onboard the ship and can be flown over large areas of the seabed, photographing and collecting samples. Fellow collaborators from Ghent University, Belgium are the contingent aboard the ship responsible for the maintenance and operation of the ROV- otherwise affectionately known as ‘Suzee’. Everyone is excited to see Suzee do her first dive into the ocean. Many weird and wonderful creatures can be caught on camera by these devices and certainly on first time viewing you could be forgiven for believing they were pictures from the moon!
Members of the biology team and oceanographic scientists instead busied themselves with the deployment and sampling of the CTD (a device which profiles the conductivity, temperature and depth at several intervals throughout the water column and which collects water samples that will be filtered and analyzed for phytoplankton, productivity and nutrients) at the head of Flandres Bay. We hope to deploy this device multiple times whilst in the bay, and will use data collected from each cast to build a comprehensive picture of what the water column looks like oceanographically and biologically.
Work on and the processing of the whale bone lander, recovered on 8th January off Vega Island was also concluded today. This was a relief for us and for the majority of the people onboard as whale bones are notoriously foul smelling (they produce a rotten egg smell common in anoxic marine environments and processes of decay), and this meant the bones could be packaged up and stored frozen before being deployed again later in our cruise schedule. Several species of worm, including the bone eating worm Osedax sp, were identified on several of the whale vertebrae. Further work will be undertaken on these specimens once we return to the lab in Hawaii, including morphological and molecular taxonomy to evaluate the evolutionary relationships of these worms.
12 January - As the sun rose on the morning of the 12th we continued our journey into open ocean, out of and away from the fast ice that had hampered our progress on the east side of the Peninsula, and bound for the west. From here, the two helicopters we have onboard will transport teams of glaciologists to sites on the Peninsula, where rock geology will be described, ice characteristics measured and the installation of field stations will occur, allowing for long term monitoring of glacial features.
As one of few people who have been lucky enough to visit Antarctica and spend time here working, I (Laura) can honestly say you never tire of the sights and sounds this incredible landscape has to offer. Our journey to the west side of the Peninsula was no exception. I am glad to say our passage was both smooth (for those prone to seasickness amongst us) and idyllic, and provided yet another backdrop of beautiful scenery, during which we were treated to sights of snow-capped mountains, blue open-ocean and floating masses of ice. We made steady progress over the morning passing through the Antarctic Sound, along the coast, and down through the Bransfield Strait into the Gerlache Strait. This area is also renowned for whale-spotting and sure enough several sightings of both Minke whale and Humpback whale were made today close to the ship. These majestic animals are common in these waters, transiting, feeding and using the area as a mating ground. All aboard the ship were happy and excited to welcome our new visitors and were equally anxious for them to stay around long enough to make the most of an amazing photo opportunity.
This side of the Peninsula is characterized by an array of glacial fjord systems and it is from these sheltered inlets that we intend to monitor the weather and co-ordinate helicopter missions when conditions are suitable for flying. Glacial fjords are unique environments influenced greatly by processes of sedimentation, water circulation and glacier retreat which
vary along the length of the fjord system. Consequently, the marine animals living on the sea floor of these areas are of biological interest to scientists. Therefore, in an effort to make the most of our new location and take advantage of a unique opportunity to sample the animals in these fjordic systems the biology team intend to photograph, survey and document
the animals living on the seabed. This will be done using an underwater ‘yoyo’ camera system- a camera which is lowered to the seafloor, and allowed to contact the seabed at which point a contact switch is triggered and a picture is taken. The camera is then brought off the sea bed a couple of meters, whilst the ship moves slowly a long a transect, and lowered again in a ‘yoyo’ like motion until a series of pictures are taken. We will also use a remote operated vehicle (ROV)- a robot on a cable which is piloted by an operator onboard the ship and can be flown over large areas of the seabed, photographing and collecting samples. Fellow collaborators from Ghent University, Belgium are the contingent aboard the ship responsible for the maintenance and operation of the ROV- otherwise affectionately known as ‘Suzee’. Everyone is excited to see Suzee do her first dive into the ocean. Many weird and wonderful creatures can be caught on camera by these devices and certainly on first time viewing you could be forgiven for believing they were pictures from the moon!
Monday, January 18, 2010
Ice Bound and Solid Phase Oceanography
11 January – After the excitement of recovering the whale-bone lander, we headed south around the east side of James Clark Ross Island, aiming for the Larsen B area. As we processed our bone samples, we entered the pack ice, pushing aside larger flows and crushing smaller ones. “Pack ice” is sea ice that has broken into floes of various sizes ranging from pool tables to football fields. Interspersed within the pack ice are tabular bergs that have broken off an ice shelf formed by massive glaciers entering the ocean. An icebreaker does not simply slice or slip it way through the ice; it plows and cracks its way forward, in the process shaking listing, rumbling, and growling. The cacophony and vibrations affect every space on our 307 foot ship (bunks included); the sound is load enough to prevent all conversation on the main deck forward of amidships. This includes the mess, where communication during meals is restricted to yelling.
Tabular iceberg, and natural ice sculpture, as we enter the pack ice east of Ross Island in the Weddell Sea.
After eight hours of breaking through pack ice, we had made only 20 miles and it became clear that 4-5 days would be required to reach our first destination, Robertson Island, on the edge of Larsen B. We thus decided to head back north around Ross Island and try the western passage, where fast ice (unbroken ice frozen this last winter) was still
in place. We hoped that this would be thinner (less than 2 m thick) and more brittle, allowing the N.B. Palmer to crack through. By the next morning (10 Jan), we plowed into fast ice stretching to the horizon, at first making five knots through a frozen meter white. Then our ship abruptly listed to starboard and ground to a halt; we were stopped by the ice! Our intrepid vessel backed up and then rammed the ice at 7 knots, allowing us to progress for a few more miles before tilting to a halt. The sensation was very much like a sleigh ride over icy snow into a deep snow drift. The ship backed up and tried another route through the fast ice but we still ground to a halt after a couple of miles. Even thought the ice appeared to be only 1 m thick and our vessel Palmer is rated to break 2-m of ice, we were stuck – no more forward progress was possible. Visions of Shackelton on the Endurance danced in our heads. By this time, it was 8 pm on 10 Jan, so we decided to take a rest for the night, and deploy the helicopters for ice reconnoiter and our first rock sampling on the morrow.
The helmsman's view from the ship's bridge as the N.B. Palmer pushes into the fast ice west of Ross Island. It is almost like moving through an Iowa cornfield in cold, snowy winter!
The morning of 11 Jan revealed a glistening white seascape, 2 successful helicopter operations and our fist oceanographic sampling. While the helos flew south and west, the oceanographers“walked on water,” conducting solid-phase oceanography. The ship lowered its gangplank onto the ice, allowing a party of eight to stroll several hundred meters from the ship to collect ice cores and associated ice algae. Ice coring uses tools developed in the 1800’s powered by elbow grease. We collected three cores of10–cm in diameter to measure ice thickness, temperature, and to recover ice algae (diatoms that thrive in the sea ice matrix) for a variety of analyses. The ice crumbled as it fell out of the core tubes; it was “rotten,” i.e., riddled with melt pockets, through most of its 100 cm thickness. this explained why the N.B. Palmer could not break through; the ice crumbled and piled up in front of the vessel, rather than cracking and letting the ship pass through. Bad news for our “icebreaker” because it is not designed to be an “ice dozer”.
One of our two helicopters lands on the N.B. Palmer after the first successful helo operation from the ship during our cruise.
Laura walking on water in front of our ice-bound ship. "I feel like Shackleton!"
Craig uses state-of-the-art technology (a Kovacs Ice Corer) to take an ocean water sample (we call this "solid-phase oceanography"). The party in the background is collecting additional ice cores, measuring the sea-ice temperature, and planning a snowball fight.
After a few hours the helicopters returned with further bad news; rotten fast ice and pack ice continued for the 80 miles into our study area with no open water channels (or “leads”) for the ship to pass through. After much deliberation, the scientific party and ship’s captain decided to abandon the icebreaking for now, and head around to the west side of the Antarctic Peninsula to conduct our helicopter installations of ice and geological stations on glaciers and land. The Antarctic Peninsula is so narrow that our helicopters can fly the 20-40 miles from the west side over the top of the Bruce Plateau to Larsen B, given clear flying conditions to 6000 feet. The evening of 11 Jan found us retracing our course through the fast ice, pushing through our day-old “wake” at 7 knots. All aboard the ship were disappointed by this set back, but hope that we will be able to return soon, once the ice has melted or blown out along the east side of the Antarctic peninsula. It is a bit ironic that our project to study climate warming in the Larsen B area is being held back by an unusually later summer breakout of sea ice!
Retracing our "steps" out of the fast ice in the Gustav Channel. Our course is not difficult to follow!
Tabular iceberg, and natural ice sculpture, as we enter the pack ice east of Ross Island in the Weddell Sea.
After eight hours of breaking through pack ice, we had made only 20 miles and it became clear that 4-5 days would be required to reach our first destination, Robertson Island, on the edge of Larsen B. We thus decided to head back north around Ross Island and try the western passage, where fast ice (unbroken ice frozen this last winter) was still
in place. We hoped that this would be thinner (less than 2 m thick) and more brittle, allowing the N.B. Palmer to crack through. By the next morning (10 Jan), we plowed into fast ice stretching to the horizon, at first making five knots through a frozen meter white. Then our ship abruptly listed to starboard and ground to a halt; we were stopped by the ice! Our intrepid vessel backed up and then rammed the ice at 7 knots, allowing us to progress for a few more miles before tilting to a halt. The sensation was very much like a sleigh ride over icy snow into a deep snow drift. The ship backed up and tried another route through the fast ice but we still ground to a halt after a couple of miles. Even thought the ice appeared to be only 1 m thick and our vessel Palmer is rated to break 2-m of ice, we were stuck – no more forward progress was possible. Visions of Shackelton on the Endurance danced in our heads. By this time, it was 8 pm on 10 Jan, so we decided to take a rest for the night, and deploy the helicopters for ice reconnoiter and our first rock sampling on the morrow.
The helmsman's view from the ship's bridge as the N.B. Palmer pushes into the fast ice west of Ross Island. It is almost like moving through an Iowa cornfield in cold, snowy winter!
The morning of 11 Jan revealed a glistening white seascape, 2 successful helicopter operations and our fist oceanographic sampling. While the helos flew south and west, the oceanographers“walked on water,” conducting solid-phase oceanography. The ship lowered its gangplank onto the ice, allowing a party of eight to stroll several hundred meters from the ship to collect ice cores and associated ice algae. Ice coring uses tools developed in the 1800’s powered by elbow grease. We collected three cores of10–cm in diameter to measure ice thickness, temperature, and to recover ice algae (diatoms that thrive in the sea ice matrix) for a variety of analyses. The ice crumbled as it fell out of the core tubes; it was “rotten,” i.e., riddled with melt pockets, through most of its 100 cm thickness. this explained why the N.B. Palmer could not break through; the ice crumbled and piled up in front of the vessel, rather than cracking and letting the ship pass through. Bad news for our “icebreaker” because it is not designed to be an “ice dozer”.
One of our two helicopters lands on the N.B. Palmer after the first successful helo operation from the ship during our cruise.
Laura walking on water in front of our ice-bound ship. "I feel like Shackleton!"
Craig uses state-of-the-art technology (a Kovacs Ice Corer) to take an ocean water sample (we call this "solid-phase oceanography"). The party in the background is collecting additional ice cores, measuring the sea-ice temperature, and planning a snowball fight.
After a few hours the helicopters returned with further bad news; rotten fast ice and pack ice continued for the 80 miles into our study area with no open water channels (or “leads”) for the ship to pass through. After much deliberation, the scientific party and ship’s captain decided to abandon the icebreaking for now, and head around to the west side of the Antarctic Peninsula to conduct our helicopter installations of ice and geological stations on glaciers and land. The Antarctic Peninsula is so narrow that our helicopters can fly the 20-40 miles from the west side over the top of the Bruce Plateau to Larsen B, given clear flying conditions to 6000 feet. The evening of 11 Jan found us retracing our course through the fast ice, pushing through our day-old “wake” at 7 knots. All aboard the ship were disappointed by this set back, but hope that we will be able to return soon, once the ice has melted or blown out along the east side of the Antarctic peninsula. It is a bit ironic that our project to study climate warming in the Larsen B area is being held back by an unusually later summer breakout of sea ice!
Retracing our "steps" out of the fast ice in the Gustav Channel. Our course is not difficult to follow!
Tuesday, January 12, 2010
Arriving in Antarctica
10 January – *Antarctic Sound and Whale Bone Lander Recovery.* We awoke on the morning of 9 Jan to sunlight glinting off nearby icebergs and distant glaciers as we passed through the Antarctic Sound. In these protected waters, the ocean was smooth and we made excellent time through the extraordinary scenery of the Antarctic Peninsula. By 6 in the evening (1800 hrs) we were off Vega Island in the Weddell Sea, in position to recover a free-vehicle whale-bone experiment placed on the seafloor 10 months earlier. The “bone lander” consists of specialized animals that colonize whale bones. The lander is dropped to the seafloor with flotation, a lead ballast weight, and an acoustic release holding the weight; at the end of an experiment, the acoustic release drops the weight following an acoustic signal from the research vessel, rising to the ocean’s surface with whale bones for recovery. Such landers are generally reliable but certainly not failsafe – they fail to surface about 5-10% of the time, often for no obvious reason. Thus, recalling a lander always is filled with suspense, especially if your scientific research (i.e., job) depends on it. This bone lander gave us plenty of suspense, remaining on the seafloor for an hour after it was recalled. Finally it surfaced, apparently having been fouled on a glacial boulder until the bottom current shifted directions. To our delight, the recovered whale bones were covered with a special fauna --- hundreds of bone eating worms called Osedax (picture 10) that especially like whale bones, mats of sulfur bacteria, and thousands of segmented (poychaete) worms in the family Dorvilleidae, which contains a remarkable diversity species living on whale bones throughout the oceans. Our small seafloor ecology group (Laura Grange, David Honig and Craig Smith) spent 2.5 days (broken by 6 hours sleep) painstakingly picking the animals off the whale bones, preserving some for DNA analyses, some for food web studies using stable isotopes, and some for biodiversity studies using classical taxonomy (i.e., based or animal “shape” or morphology). Although exhausted by the end of our bone-processing ordeal, we were in excellent spirits. It is clear that we have new species of whale-bone animals, and that we will fill in an important gap in the biogeography and feeding ecology the global “whale-fall fauna,” helping the elucidate the effects of whales, and the impacts of whaling, on marine biodiversity around Antarctica. By the time we had finished our whale-bone tasks, we were stuck in the sea ice, but that is a story yet to come.
The mucus tubes of the whale-bone eating worms Osedax on a whale bone recovered after 10 months on the seafloor in the Weddell Sea, Antarctica.
The mucus tubes of the whale-bone eating worms Osedax on a whale bone recovered after 10 months on the seafloor in the Weddell Sea, Antarctica.
Rough Seas!
8 Jan 2010 – *“We’re crossing the Drake!”* This phrase has filled sailors and Antarctic explorers with trepidation for centuries. Why? Because the Drake Passage is considered the roughest water body in the world. It lies between Cape Horn and the tip of the Antarctic Peninsula -- a 480 mile channel concentrating the storms and currents circling the globe in the Southern Ocean. Like any body of water, it is not stormy all the time; storm systems pass through at 5 to 10 day intervals. My 9 previous crossings of the Drake have been mostly pleasant with the ship surfing large swells amid black browed albatross who skim the waves for without flapping a wing. This crossing also began smoothly with a
pleasant sunset and modest seas in the evening of 5 Jan; however, things changed quickly. By the wee hours of 6 Jan the wind howled from the northwest even though no storm had been forecasted. For twelve hours we had sustained winds of 55 knots, with gusts of 96+ (well above hurricane force). The seas reached forty feet, washing over the back deck and making our heavily loaded ship roll like a carnival ride. Most of the glaciologists and land geologists suffered from “mal mar” and spent the day in horizontal in their bunks or watching movies in the lounge. A few hardy oceanographers and the ship’s crew populated the labs and mess deck, but the weather was so rough that even the galley (the ship’s kitchen) curtailed operations, serving cold cuts for dinner. Captain Joe Borowski altered course and held a weather pattern for 18 hours, heading theshp diagonally into the seas to ease the motion, but taking us off course. Fortunately, by the late evening of 6 Jan, the wind and seas had abated and we resumed our heading (albeit a bit bumpily) for the tip of the Antarctic Peninsula. Our horizontal shipmates reappeared the next morning, looking very releaved that the final three days of the crossing were relatively smooth, allowing us to rounding the tip of King George Island in good time. The lesson of this crossing was clear: never take the Drake lightly -- howling gales and mountainous seas can come seemingly from nowhere, making life miserable for seafaring souls!
Iceberg in the Antarctic Sound shaped like a wolf's head.
The back deck of the N.B. Palmer, awash during the Drake Passage storm. This normally our work area for collected oceanographic samples.
pleasant sunset and modest seas in the evening of 5 Jan; however, things changed quickly. By the wee hours of 6 Jan the wind howled from the northwest even though no storm had been forecasted. For twelve hours we had sustained winds of 55 knots, with gusts of 96+ (well above hurricane force). The seas reached forty feet, washing over the back deck and making our heavily loaded ship roll like a carnival ride. Most of the glaciologists and land geologists suffered from “mal mar” and spent the day in horizontal in their bunks or watching movies in the lounge. A few hardy oceanographers and the ship’s crew populated the labs and mess deck, but the weather was so rough that even the galley (the ship’s kitchen) curtailed operations, serving cold cuts for dinner. Captain Joe Borowski altered course and held a weather pattern for 18 hours, heading theshp diagonally into the seas to ease the motion, but taking us off course. Fortunately, by the late evening of 6 Jan, the wind and seas had abated and we resumed our heading (albeit a bit bumpily) for the tip of the Antarctic Peninsula. Our horizontal shipmates reappeared the next morning, looking very releaved that the final three days of the crossing were relatively smooth, allowing us to rounding the tip of King George Island in good time. The lesson of this crossing was clear: never take the Drake lightly -- howling gales and mountainous seas can come seemingly from nowhere, making life miserable for seafaring souls!
Iceberg in the Antarctic Sound shaped like a wolf's head.
The back deck of the N.B. Palmer, awash during the Drake Passage storm. This normally our work area for collected oceanographic samples.
Wednesday, January 6, 2010
Beginning to cross the Drake passage
5 Jan 2010 – Our passage past Tierra del Fuego was smooth with following
seas, and we just now have entered the Drake Passage. Of course, the wind immediately switched to our beam (coming from the side of the ship) so we are rocking much more. Because working on the deck of a ship can be dangerous, especially in Antarctica, we have spent the day in numerous safety briefings. These included instruction in rapid donning of a survival suit to keep us alive in frigid Antarctic waters for 12 hours if the ship sinks. These look and feel like Gumbie suits and make you break into a heavy sweat within 30 seconds (unless of course you are immersed in icy water). We also learned how to work on deck, roping ourselves to the ship when it gets rough, and warning our companions if we see a big wave coming. This expedition will also include helicopter operations to fly glaciologists ashore to sample ice and measure to flow of glaciers into the ocean; this too required a long safety briefing (in addition to the 2-day safety course we had in June!). Now it is 10 pm (but still light because we are so far south) -- time to relax a bit, reading a book, watching a movie video, or maybe even writing a blog!
seas, and we just now have entered the Drake Passage. Of course, the wind immediately switched to our beam (coming from the side of the ship) so we are rocking much more. Because working on the deck of a ship can be dangerous, especially in Antarctica, we have spent the day in numerous safety briefings. These included instruction in rapid donning of a survival suit to keep us alive in frigid Antarctic waters for 12 hours if the ship sinks. These look and feel like Gumbie suits and make you break into a heavy sweat within 30 seconds (unless of course you are immersed in icy water). We also learned how to work on deck, roping ourselves to the ship when it gets rough, and warning our companions if we see a big wave coming. This expedition will also include helicopter operations to fly glaciologists ashore to sample ice and measure to flow of glaciers into the ocean; this too required a long safety briefing (in addition to the 2-day safety course we had in June!). Now it is 10 pm (but still light because we are so far south) -- time to relax a bit, reading a book, watching a movie video, or maybe even writing a blog!
Getting ready
4 Jan 2010 – We have spent the last 6 days at the dockside in Punta
Arenas, living aboard our home for the next 60 days, the Research Vessel
Ice Breaker Nathanial B. Palmer. We were scheduled to head
south from Punta Arenas on 2 Jan, but have been frustratingly delayed by the late arrival of equipment and supplies from the USA (held up in
customs in Santiago), and high winds (hurricane force gusts up to 70
knots!) which prevented us from using the ship’s crane to load our gear
onto the vessel. This did allow us to see a bit more of Punta Arenas,
which still has the feel of a frontier town near the end of the world. This
is the port from which Shackleton sailed on a tug boat to rescue his men
from Elephant Island nearly 100 years ago; some of the windy streets,
Victorian buildings, and bars of Punta Arenas have changed little since
the “heroic era” of Antarctica work. You can almost hear Shackleton
challenging the local sea captains to sail him back to Antarctica to rescue
his men.
According to seafaring tradition, sailors heading south from Punta Arenas
to Antarctica must rub the toe of the bronze Tierra del Fuegan in the
central square of Punta Arenas to assure safe transit across
the Drake Passage. Because the Drake is known as the roughest body or
water in the world, we made sure to rub the toe on the day of our departure. So far it is has worked because we are sailing through the
Strait Magellan under a clear sky with a scenic sunset. We
will entire the Atlantic Ocean in about 12 hours, then turn south along the
coast of Tierra del Fuego for another 12 hours before actually entering the
Drake.
Arenas, living aboard our home for the next 60 days, the Research Vessel
Ice Breaker Nathanial B. Palmer. We were scheduled to head
south from Punta Arenas on 2 Jan, but have been frustratingly delayed by the late arrival of equipment and supplies from the USA (held up in
customs in Santiago), and high winds (hurricane force gusts up to 70
knots!) which prevented us from using the ship’s crane to load our gear
onto the vessel. This did allow us to see a bit more of Punta Arenas,
which still has the feel of a frontier town near the end of the world. This
is the port from which Shackleton sailed on a tug boat to rescue his men
from Elephant Island nearly 100 years ago; some of the windy streets,
Victorian buildings, and bars of Punta Arenas have changed little since
the “heroic era” of Antarctica work. You can almost hear Shackleton
challenging the local sea captains to sail him back to Antarctica to rescue
his men.
According to seafaring tradition, sailors heading south from Punta Arenas
to Antarctica must rub the toe of the bronze Tierra del Fuegan in the
central square of Punta Arenas to assure safe transit across
the Drake Passage. Because the Drake is known as the roughest body or
water in the world, we made sure to rub the toe on the day of our departure. So far it is has worked because we are sailing through the
Strait Magellan under a clear sky with a scenic sunset. We
will entire the Atlantic Ocean in about 12 hours, then turn south along the
coast of Tierra del Fuego for another 12 hours before actually entering the
Drake.
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