ABOARD THE JOIDES RESOLUTION, IN TRANSIT TO HOBART, TASMANIA– The work of the ship ended as quickly as it started nearly two months ago. We finished drilling Site 1361 and logged the hole. The drillers tripped 3500 meters of pipe and prepped it for storage as the ship will not drill again until July – off the coast of British Columbia. Everyone on board is absolutely brain dead from the non-stop grind of 12-hour shifts day after day. But all are happy as well. We’ve completed most of our objectives and made some exciting discoveries. When we did not meet with complete success it was always because of weather and ice, either encroaching sea ice or fields of icebergs so thick that we had no chance to pass.

Relaxing with some music after the work is done.

Now we have some days in transit. These days are filled with meetings to design our post-cruise research. We will all spend much more time at home working on the cores than our actual days at sea on this expedition. Some of the methods we will employ are expensive and difficult and we have recovered nearly 2000 meters of core. This means that we must carefully select the intervals we will study, so that we can answer the most important questions about Antarctic climate change as quickly as we can. For some of us, the analytical work will extend over the next 4 years. Then other scientists will work on these cores for decades to come. They will be stored in a vast library of ocean cores in College Station, Texas, at the IODP core repository where they are available to scientists from all over the world.

What I like most about these days in transit is going off shift. I no longer set my alarm to awake at 11PM. The two shifts mingle at meals and in the labs, almost as strangers at first as they have not seen much of each other for more than 7 weeks.

The whole team for Expedition 318. Photo courtesy of John Beck, IODP.

Working groups between the shifts assemble to design research strategies and timetables. I will lead a group that will make oxygen isotopic measurements of the small shells of amoeba-like organisms called foraminifera. Forams, as we call them, live for about 4 weeks during the brief Antarctic summer. They build their tiny shells out of calcium carbonate, the main mineral that makes up limestone. By measuring the ratios of two types of oxygen in the carbonate we can tell the temperature of the water in which the forams grew. We will make these analyses on forams that were living in Antarctic surface waters hundreds, thousands, and even millions of years ago to see how warm the water was next to the Wilkes Land coast. We already know from our microscope work on board that this part of Antarctica has been very warm at times, maybe 10 to 15 degrees centigrade warmer when we go back 35 million years. The foram work will help tell us exactly how warm the waters may have been during more recent periods when we know the ice sheet became much smaller. The results will help us predict the behavior of Antarctic ice in the future.

What a trip it’s been! I hope you’ve enjoyed these blogs. If you live in the Bay Area, please look for a notice about a talk I’ll likely give on this expedition in 6 months or so, after we’ve had a chance to start the shore-based part of the work. As we pull ever closer to Hobart we are very much aware that we are simply reaching the end of the beginning.

Christina and Joerg at the bow at sunset. Photo courtesy of John Beck, IODP.

Music by Synthhead. Courtesy of Beatpick.com.

Transiting back to Site U1359
Position: 64º 34’S, 140º 30’E
Water Depth: 3700 meters
The scene outside: 2 days of storms and lots of icebergs

ABOARD THE JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– Our latest drilling target is in an area where sediments that document the transition of Antarctica from the “Hothouse” to the “Icehouse” can be easily reached at shallow depth beneath the seafloor. We drilled for 18 hours and then had to pull the drill pipe up out of the hole and reposition the ship to avoid a large iceberg that was heading straight for us. When the iceberg had passed the weather started to deteriorate. Our forecast was for 60 kt winds and big seas so we headed north out of “iceberg city” to ride the storm out in deep water away from icebergs and sea ice. The forecast was true to its word – we had waves up to 30 feet and winds over 60 kts for more than 24 hours. But we had great iceberg viewing on the way to our WOW (Waiting On Weather) point so I’ll write something about them and how they fit in with our project.

The Antarctic ice sheet is always accumulating new snow that gradually turns to ice. For the ice sheet to remain the same size it must either melt or release ice to the ocean as icebergs. In parts of Antarctica some of the ice is in fact melting but most of the ice loss that maintains the continent at its present state occurs through the calving of icebergs. Most icebergs calve off of ice tongues and ice shelves – areas of concentrated ice flow at the coast. Imagine that the ice is draining off of the high parts of the continent by flowing down small ice drainages to form mighty rivers – but rivers of ice in this case. These vast rivers move slowly, only a few 10’s to 1000’s of meters each year. When they reach the coast, the ice flows out into the ocean where it begins to float wherever the water is deep enough. In some cases, this is where the water is over 500 meters deep and the ice is over 560 meters thick. Floating ice shelves or ice tongues are influenced by winds and ocean currents. They begin to melt if the water is warm enough but they mostly breakup to form icebergs.

Many of the icebergs here off Wilkes Land came from the Ross Ice Shelf – the world’s largest ice shelf. It is over 1500 km away in the Ross Sea but icebergs travel great distances in the Southern Ocean. The water is cold and they drift with the ocean currents, for decades in some cases. As they drift, they melt a bit below the waterline and become rounded. Sometimes they flip over and this rounded part is then visible. Icebergs often collide and gouge away at each other or they list over at an angle and slowly fall apart. This means that icebergs come in all shapes, sizes, and textures.

The biggest iceberg we’ve seen was over 20 km long.

Icebergs come in all colors, from the pure white of fresh snow to the deepest blue of pure crystalline ice from far below the surface of the ice sheet.

Icebergs come in all shapes, sizes, and textures.

A penguin on a growler (a small iceberg).

The ice at the base of the ice sheet often carries sediments: boulders, gravels, cobbles, and sands. When these parts break off and begin to float they form “dirty” bergs with dark rocky layers intermixed with the clear blue ice. The debris that falls from these dirty bergs accumulates in sediments at the seabed. When we see gravels or sands in otherwise fine-grained sediments, we know this debris was transported out over the ocean by ice. In fact, the presence or absence of ice-rafted debris is something we keep close track of in the cores we are collecting on this trip – this tells us whether Antarctica was generating lots of icebergs and therefore had at least some kind of ice sheet in the past. Conversely, when we see sediments that do not contain this debris we know we are looking at a record from a time when Antarctica was much warmer.

In the foreground, a dirty iceberg.

We’ve seen over 400 icebergs in the past 2 days.

As I write, the storm has abated and we are transiting back to our drill site.

Dawn at 4:30.

At Site U1359, Hole U1359B,
Position: 64º 54.25’S, 143º 57.63’E
Water Depth: 3100 meters

ABOARD THE JOIDES RESOLUTION, OFF THE COAST OF WILKES LAND, ANTARCTICA– Hi everyone! As we approach our 2000th meter of drilling I thought I would change things up a bit with this blog and send along some photos of the birds we’ve been seeing. The Southern Ocean is the coldest and windiest on Earth, but it also one of the most bountiful. During the 3 or 4 months of long days and short nights, the “farm” operates 24/7. The plants that live in the sunlit waters here are nourished by nutrients that mix upwards from the deep sea and go into overdrive building their cells. It’s easier for nutrients to mix upwards into the sunlit upper waters here simply because the water column is “isothermal”. This means that we see very little variation in the temperature of the sea between the surface and the bottom waters over 3000 meters below us. It is all close to 0 degrees Celsius. This means that it takes very little energy to move dense cold water from the deep upwards because the surface water is also cold and is almost as dense. So the plants have everything they need. The wind and circulation drive the mixing, which brings in the nutrients, and the sun keeps the farm growing nearly 24 hours every day. Plants (mostly single-celled protists called diatoms) grow fast and the small plankton that eat the diatoms grow fast as well. Which brings us to the birds…..

Albatrosses in a storm.

Our ship is constantly surrounded by Albatrosses, Petrels, and Skuas. Sometimes we see more than 100 birds surrounding the ship. They swoop and dive, looking for food in the water, either plankton or small fish, or perhaps they think we are land. We haven’t seen one try to rest on the ship yet. In fact the Albatrosses rarely set down at any time. They fly 1000’s of miles from their breeding colonies and are at sea for months and even years at a time.

Here are some photos of the seabirds we’ve seen so far.

These first two are of Black-browed Albatrosses (Thalassarche melanophrys). They live throughout the Southern Ocean and breed in places like the Falkland Islands and South Georgia. They can live to be as old as 70 years and spend long periods of time at sea, even encircling the globe. They feed on krill and small fish – that in turn eat diatoms and smaller plankton.

Black Browed Albatross

Black Browed Albatross

The most common bird we saw at our drill sites close to the Antarctic continent were the Pintados, also known as Cape Petrels (Daption capense capense). The name Pintado comes from the Spanish word for “painted”. They live throughout the Southern Ocean, mainly eating krill, especially on and near the continental shelf of Antarctica in summer. A 2009 census estimates there are over 2 million Cape Petrels alive today.

Cape Petrel (Pintado)

Cape Petrel (Pintado)

Cape Petrel (Pintado)

We’ve also been surrounded the past few days by Southern Giant Petrels (Macronectes giganteus). These are indeed big birds….females can weigh up to 18 pounds. Sometimes they are called “stinkers” as they can spit a foul-smelling liquid at predators or when they are perturbed.

Southern Giant Petrel

Southern Giant Petrel

I hope you enjoy these photos! I’ll get back to our science and progress next time and I’ll try to knock out least one more video blog. We are VERY busy with work here now but it all very exciting.

The bone lander after recovering it on the back deck of the ship. The attached whale bones will be removed and analyzed by Dr. Craig Smith and colleagues to see what animals, big and small, have made these bones their home.

While the deep sea below the euphotic zone (the top 100 or so meters, or 300 ft, where light penetrates and primary production from algae occurs) was long thought as a vast oceanic desert where few organisms (even microbes) could survive, research in the last century starting with the Challenger Expedition between 1872-1876 has shown a rich diversity of marine life specialized to face the harsh conditions of high pressure, cold temperature, and complete darkness. One of these, the annelid worm Osedax, has developed the ability to feed on complex hydrocarbons in whale bones, using bacterial endosymbionts (bacteria living inside the worms) to break down the compounds inside the bones into a usable form of energy.

Our ship, the Palmer, breaking through sea ice in the Weddell Sea.

As luck or fate would have it, the sea ice around Antarctica seems to be unusually persistent this year, reaching far beyond its usual summer extent, which makes moving forward a slow going process. For those of you living in cold regions of the United States and the world, you might be used to seeing your lakes and rivers freeze and thaw as the seasons progress. Sea ice around the Antarctic goes through much of the same cycle, building during the winter (between April and September in the Southern Hemisphere) and melting during the summer. The extent of ice any given year is related to weather as well as global climate, and has been shown to decrease around the Antarctic Peninsula over the past 60 years.

Sea ice extent in September (austral winter) of 2009 as measured by satellite. Black corresponds to land, blue to open water, and the other colors to sea ice. The approximate location of the Larsen B ice shelf, our target, is indicated by a white circle. Notice the band of purple surrounding that location, indicating persistent sea ice.

Sea ice extent in December (summer) of 2009 as measured by satellite.

Here’s another view of the same data. In this version, grey corresponds to land, blue to open water, and white to sea ice. The approximate location of the Larsen B ice shelf, our target, is indicated by a black circle.

Sea ice extent in December (summer) of 2009 as measured by satellite.

Because the Antarctic serves as home to a rich assemblage of species, including fish, seals, sea birds, whales, and penguins, you can imagine that life doesn’t simply stop in the cold polar winter… it adapts. Algae, which you may think as growing only in bodies of water such as lakes, oceans, and rivers, can also grow on the underside and inside of sea ice. If you look at the picture of our ship’s track you’ll notice a surprising brown color to the normally white or bluish ice. This color is due to ice algae, which due to their adaptation to low light conditions thrive both in the summer and winter. Ice algae may play an important role in starting the phytoplankton blooms that are common in the ocean as the ice retreats in the spring. Because it grows in such great abundance it also provides an important source of food to higher trophic levels, include the krill that whales love to eat. So in a way, what happens on the often hidden underside of ice can have a great impact on the bigger Antarctic animals we all know and love!

Cracks in the sea ice expose algae growing underneath and inside the ice.

View of Antarctica from above the South Pole. Notice that the tip of South America is the only bit of land showing in this view. The body of water surrounding Antarctica you see in this image is the Southern Ocean.

This time around the Drake Passage greeted us with up to 50ft waves and up to 100 knot wind gusts (1 knot equals 1 nautical mile per hour), enough to make this boat feel like a small cork bobbing around in an endless ocean. Walking straight is no option, nor is getting much work done. To make sure everything and everyone is safe scientists, crew, and support staff make sure that everything from computers to chairs and the two helicopters we have on board are tided down to the boat. As the ship rolls, sometimes 16 degrees from side to side, waves break over the side and occasionally drown the deck underneath a wall of water. Our ship the NBP is built to withstand this kind of punishment, and she and us continue our trek towards Antarctica.

Water spilling over the side of the ship as it rolls in 50ft seas across the Drake Passage. Compare this image to one taken on a calm day (next photo). It really was a wall of water coming down on us.

A calm day.

Debra, Laura, and Mattias trying on survival wetsuits. These suits (nicknamed ‘gumby suits’) are meant to keep us warm in the event that the boat capsizes.

Birds, which form an important part of the marine food web partly because of their consumption of fish and other marine life, are on the other hand old hats at dealing with the storm, carefully dodging breaking waves and using the strong winds to glide gracefully in the air. As we move South the species composition of birds sighted from the ship changes. Wandering, Black Browed, and Sooty Albatrosses are common near South America. Soon Cape Petrels start to appear, along with Southern Giant Petrels. Down in the Antarctic we’ll hopefully be seeing Antarctic Terns, Petrels, and Wilson’s Storm Petrels, graceful birds named after their affinity for stormy weather that seem to tip toe on the water’s surface.

Wandering albatross gliding over the waves. These are the world’s largest birds, with a wingspan of up to 142 inches (363 cm). That’s almost 12 feet! They spend almost their entire life at sea, riding the strong winds of the Southern Ocean.

As we cross we hope conditions will calm down and look forward to reaching the Weddell Sea, the sea East of the Antarctic Peninsula, and eventually the Larsen Ice Shelf System. On our way we will be recovering a ‘whale bone lander’, a metal frame that has been placed at the bottom of the ocean in 600m of water, and on which bones from different species of whales have been placed. Biological oceanographer Craig Smith from the University of Hawaii is interested in the organisms that colonize bones in the deep sea, including Osedax, the bone-eating worm. More on that in the next dispatch. Our group, which focuses on phytoplankton (microscopic algae) in the water column (between the surface and the ocean bottom) will be starting to sample the surface water to see what lives in the uppermost layer of the ocean. Like the birds, the phytoplankton community changes as we move south, and this can have important consequences for the rest of the food chain.

View of the skyline of Punta Arenas, Chile.

Packing for a research expedition to Antarctica is a bit different from your average trip. Antarctica is far away from mostly everything, and can be very cold and rough at times. No detail is small enough, including what clothes to wear. Upon arriving in Chile, we were issued Extreme Cold Weather gear to make sure we were equipped to work in any and all conditions we could face. When spending 59 days at sea, the little comforts of life (including being dry and warm) can make a huge difference.

Clothing issue at the United States Antarctic Program (USAP) counter.

While choosing what clothes to wear can seem tricky enough, figuring out what scientific equipment to bring and how to get it to the southernmost tip of South America before loading it on the ship, presents even greater of a challenge. This project brings together scientists studying a wide array of subjects, from oceanography, geology, to glaciology and biology, to try to understand how the ecosystem of the Larsen B ice shelf has changed since its break up in March 2002. And to accomplish these lofty goals, participants have brought a whole slew of instruments to measure everything from sediments, to ice thickness, and algae concentrations. The oceanographic ‘toys’ we’ll be working with include a CTD rosette (named after variables it measures, Conductivity, Temperature, and Depth) to sample water from the surface to thousands of meters deep, a Remotely Operated Vehicle (ROV) to get live video feed of the ocean floor, coring equipment to bring samples from the ocean floor back to the surface and to collect ice cores to look at ice algae, and even helicopters to allow scientists onboard to sample ice and rocks from the continent itself. It takes time to assemble this kind of gear, and we are now stuck waiting for everything to be loaded and organize. It’s amazing how little space there is on a ship the size of a football field!

The ROV (nicknamed Suzee) getting put together and cleaned on the back deck.

We’ll be bringing you updates from Antarctica as often as we can, and will be talking about both the science and life onboard our research vessel. Please post any questions you have on the website, or send them directly to me at mattias.cape.guest@nbp.usap.gov and I’ll try to answer by my next post. I know working in the Antarctic can seem strange and out of reach, but you’d be surprised the many different paths people onboard this ship have taken to get to where they are. You don’t have to be a scientist to experience the Southern Ocean and the Antarctic! None of our work would be possible without the help of the ship’s captain, crew, engineers, and science support staff.

View of the RVIB Nathaniel B. Palmer at night.

For some time it was thought that Weddell seals did not eat the toothfish and therefore would not be affected by the reduction of these fish in the ocean. The fishing industry has pushed to increase catch limits based on this assumption. We’re learning, though, that this is not true by indirect means.

One way researchers determine what an animal eats is by sorting through their scats (body waste). Indigestible parts pass through the body of seals and whales and can be identified. In the case of fish, the ear bones, or otoliths, are used to determine not only what species of fish are eaten, but how old and large they are. Toothfish otoliths have not been found in seal waste. But recently we’ve learned why.

Antarctic Toothfish ear bone (otolith).

As is the case with many discoveries chance plays a large part. While out on a diving expedition one researcher discovered the heads of many toothfish near a crack in the ice. The only predators in the area are seals, so these heads must be the remains of their meal. No wonder there are no otoliths in the seal waste, they don’t eat the heads! By observing seals in holes drilled through the ice for scuba access, it has been observed that seals remove the heads so this information was already known. But many people still doubt the implications of this or contend that it is a ‘local’ phenomenon. Finding these heads, in the company of seal holes, was another clear indication that this belief is wrong. Retrieving these heads would also mean that scientists could remove the ear bones (otoliths) and determine the age of the fish as well as where the fish grew up (one of the many mysteries about toothfish that remains unsolved).

The crack, where seals come to find toothfish hiding under the ice.

The helicopter landed us in this remote place on the McMurdo ice shelf.

So off we go. First a helicopter ride to the place where the fish heads were first found, and then a 10 km walk over and around the rough terrain along the crack in search of other evidence. All in all the remains of 30 fish were found, and 20 heads were brought back to the lab to extract the otoliths.

Antarctic toothfish heads, the remains of a Weddell seal feast.

Searching for Antarctic Toothfish heads on the McMurdo Ice Shelf crack.

Bagging Antarctic Toothfish heads.

As it turned out, most of the heads had become mummified, i.e. freeze-dried, and acidic action in the flesh during the process of decomposition in many cases dissolved the otoliths. There were just little ‘puffs’ of white stuff where the otoliths should have been. Skuas had eaten the otoliths in other of the heads. But, we did find otoliths in 6 heads, and these will be tested and analyzed in a lab in the US. Providing evidence to fishery biologists that toothfish are an important food source for seals will help the argument to limit the commercial catch.

Learn more about Antarctica toothfish and conserving the Ross Sea for all marine organisms by visiting The Last Ocean.