Ice Stories: Dispatches From Polar Scientists » Mattias Cape http://icestories.exploratorium.edu/dispatches Mon, 15 Nov 2010 20:40:36 +0000 http://wordpress.org/?v=2.9.2 en hourly 1 When an Icebreaker Meets Its Match http://icestories.exploratorium.edu/dispatches/when-an-icebreaker-meets-its-match/ http://icestories.exploratorium.edu/dispatches/when-an-icebreaker-meets-its-match/#comments Sun, 10 Jan 2010 01:46:17 +0000 Mattias Cape http://icestories.exploratorium.edu/dispatches/?p=2177 N. B. PALMER, ON 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...]]> ABOARD THE RVIB N. B. PALMER, ON THE WEDDELL SEA– After making our way through the Antarctic Sound at the tip of the Antarctic continent we proceeded south where after a bit of searching we recovered the whale bone lander. As whales die their carcass often sinks to the bottom of the ocean, providing an important source of food to the deep sea. These whale falls are rapidly colonized by a thriving community which include sea stars, annelid worms, hagfish, and other scavengers. Dr. Craig Smith’s mooring provides a controlled way of studying the organisms that specifically colonize whale bones, feeding on the oils and other compounds they contain. Processing those samples, which involves carefully picking off all organisms and sometimes cutting the bone itself, will take days, and as you can imagine will be one smelly job (enough that the rest of us on the ship knows what is happening).


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.
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A Small Cork in a Big Ocean http://icestories.exploratorium.edu/dispatches/a-small-cork-in-a-big-ocean/ http://icestories.exploratorium.edu/dispatches/a-small-cork-in-a-big-ocean/#comments Fri, 08 Jan 2010 01:35:20 +0000 Mattias Cape http://icestories.exploratorium.edu/dispatches/?p=2176 N. B. PALMER, ON THE SOUTHERN OCEAN-- After leaving Punta Arenas, Chile, on January 4th, 2010, and enjoying the calm waters of the Straits of Magellan and the coast of Argentina on our way to the Weddell Sea we have now reached the dreaded Drake Passage....]]> ABOARD THE RVIB N. B. PALMER, ON THE SOUTHERN OCEAN– After leaving Punta Arenas, Chile, on January 4th, 2010, and enjoying the calm waters of the Straits of Magellan and the coast of Argentina on our way to the Weddell Sea we have now reached the dreaded Drake Passage. The Drake is a stretch of ocean between the tip of South America and the Antarctic that most ships bound for the Antarctic Peninsula have to cross, and where bad weather and big seas are the norm. Unlike elsewhere in the world the ocean surrounding Antarctica, the Southern Ocean, forms a continuous belt of water around the continent above which all other land masses in the world lay. The Antarctic Circumpolar Current which flows around Antarctica is therefore unhindered by any land mass. As storms form in the Southern Ocean and the winds strengthen, the seas can sometimes become very rough, with very large waves that can be very dangerous to ships that venture there.


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.

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Pack Your Many Bags, We’re Off! http://icestories.exploratorium.edu/dispatches/pack-your-many-bags-we%e2%80%99re-off/ http://icestories.exploratorium.edu/dispatches/pack-your-many-bags-we%e2%80%99re-off/#comments Mon, 04 Jan 2010 19:59:33 +0000 Mattias Cape http://icestories.exploratorium.edu/dispatches/?p=2175 Nathaniel B. Palmer is waiting for us...]]> PUNTA ARENAS, CHILE– After leaving the day after Christmas from San Diego, CA, we’ve finally made it to Punta Arenas, Chile, where our ship the RVIB (Research Vessel Ice Breaker) Nathaniel B. Palmer is waiting for us. During our port call we’ll be loading all our equipment onto the ship and getting ourselves ready for the crossing of the Drake Passage and work down in the Antarctic.


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.
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