A new age of discovery

A new age of discovery

The large-scale expeditions Tara Arctic (2006-2008) and Tara Oceans (2009-2012) were received with great acclaim by the scientific community.

In the science world, data collection is only the tip of the iceberg. Before a scientific article can be written the data is subjected to a long period of analysis, comparison and supplementary research. Much time is required between starting the research and finally making the findings « official » by publishing them. According to Éric Karsenti, research director at the CNRS (France’s National Centre for Research) and at the European Molecular Biology Laboratory (EMBL), this can take several years even for projects with a limited data collection phase. However for such large-scale projects as the Tara expeditions « operations take place on a completely scale », he says.

Tara Oceans gradually unveiling the secrets of plankton

It has been four years since the launch of this last expedition, involving the CNRS, the French Alternative Energies and Atomic Energy Commission and the EMBL, and already eight scientific articles have been published. This gives an idea of the huge amount of knowledge that it will be possible to draw from Tara Oceans. One of these articles, for example, reveals the relationship between certain viruses and other planktonic organisms. Éric Karsenti is particularly pleased with this work: « It’s the first publication to show how data from the Tara can be employed to explain interactions between different organisms. One of the aspects we were really keen to understand was what interacts with what in the ocean. » These initial results are exciting and concern just one of the many fields of research covered by the Tara Oceans project. Moreover this particular study only focused on seventeen of the samples collected during the expedition. In all, Tara Oceans brought back some 28,000 samples, which provides an indication of the wealth of findings to come. Other publications released in recent months include the explanation of a new method for analysing bacterial diversity in samples and the description of a new species of coral discovered in the Gambier Islands (Pacific Ocean). There is still an enormous amount of data analysis to be done, which explains why such articles have so far been limited to a few highly-specific topics. The sequencing of all of the samples alone is expected to take two to three years. « We are currently working on a publication on global and local diversity in eukaryotes*, how they differ from one region to another » says Éric Karsenti. « Another study due to be published comprises a global catalogue of bacterial genes ».

For the time being though people will have to settle for the preliminary results. Thanks to the Tara Oceans expedition there are now thought to be over a million species of protists**, whereas previous estimates considered there to be around 100,000. Sequencing performed on protist samples from twenty-eight of the 153 sampling stations revealed that eight-five per cent of them had previously unknown DNA sequences. In addition to the studies carried out by the Tara Oceans project teams, a whole host of further research may be started in coming years. One such project called Oceanomics*** is already underway. This project consists of structuring the thousands of samples and data collected during the Tara Oceans expedition to understand the nature and functioning of world the wide planktonic biodiversity and eventually extract certain bioactive planktonic compounds that show promise for, for example, biofuels and pharmaceutical applications.

The first data sets will be made available online to the scientific community by the end of the year. Éric Karsenti says: « It is without doubt the most signif icant achievement of an expedition like this. It is similar to a library where researchers the world over will be able to work on the Tara Oceans samples, and who knows what might be the result. »

Tara Arctic improving understanding for better forecasting

The Tara Arctic Drift of 2006 to 2008 has already led to the publication of over two dozen scientific publications. A substantial quantity of information has already been analysed, according to Jean-Claude Gascard, research director at the CNRS who was in charge of the scientific programme for Tara Arctic and of the DAMOCLES research programme: « The data collected during the expedition will serve as a reference on an Arctic system undergoing profound transformation and I wouldn’t be surprised if people are still publishing works based on this data ten years from now. » The first major result to come out of Tara Arctic concerned the drift process itself and this has led to several publications. The expedition was originally planned to take a thousand days, as the Fram had done over a century before. However the Tara completed the drift in just 500 days, demonstrating the increase in Arctic ice drift speed. Following this initial major finding, several works were published on the interactions of the three Arctic system components: ice, atmosphere and ocean. « The Tara has helped to highlight the formation of ice crystals, called Frazil ice, which rise to the surface », explains Jean-Claude Gascard. « The existence of this phenomenon in Antarctica was already well known, but we managed to show that it is a major phenomenon in the formation of Arctic ice too ». As regards atmosphere, research conducted aboard the polar schooner has helped to achieve a better definition of the lower Arctic atmosphere which is in contact with the ice and which is essential to air-ice interactions. « We had very little information on these lower levels which are difficult to study with satellites and automatic stations » Gascard says. « Indeed, the advantage of Tara Arctic is having people on board to operate instruments that we don’t yet know how to automate ». Finally, several publications have investigated ice sheet movements through the application of seismological techniques. All of the findings from the data collected during the Tara Arctic Drift will help achieve a better understanding of the complex Arctic system, and thus improve forecasting models. These it systems simulate the behaviour of the atmosphere, oceans and ice to provide short-term scenarios, ice charts and weather forecasts, as well as more long-term simulations which are crucial to research on climate change. Within the next few years conclusions drawn from Tara Arctic, in addition to other research, will be integrated into the various digital models to improve forecasting capacity. We are therefore already on track towards the first concrete applications of research conducted aboard the Tara.

Yann Chavance

Read this article on Tara’s 10 years journal

* : Single-celled or multicellular organisms that are characterized by the presence
of a nucleus.
** : Unicellular organisms with nuclei that are the ancestors of all forms of life.
Certain types are photosynthetic, such as diatoms.
*** : The Oceanomics project – wOrld oCEAN biOresources, biotechnology,
and earth-systeM servICeS – won the French government’s ‘Investments

In the Uummannaq fjord

Since late Friday afternoon, after crossing the Baffin Sea without incident, Taranautes are relishing the thousand wonders that make up the beauty of the Uummannaq fjord (Greenland).

In this fjord which opens on the west coast of this icy giant island, on Saturday the scientific team will carry out a long sampling station at the surface, and to a depth of 400 meters.

At the center of this landscape surrounded by high snowy mountains, lies the island of Uummannaq. Covering an area of 12 km2, it is dominated by a rocky peak 1,175 meters high and is named after its shape. Uummannaq means heart in Greenlandic.

This is another one of those places that make you love life and appreciate the chance to “be here”. This is what we wish for people we love who for some reason or other can not travel. A gift of nature which, besides the purely visual pleasure, nourishes your soul.

This is what the 14 aboard felt after traveling the first few miles. There are colors, sculptured icebergs, and snow-capped mountain chains, often with steep cliffs taking on reddish hues at dusk.

This Saturday morning after a good night spent drifting among the icebergs, the scientific team returned to the task in splendid sunshine. This fjord is full of diverse little treasures  which Lars Stemmann, chief scientist, intends to identify. To begin with, the mysterious “brines” * — these very cold surface waters from the previous winter which sink until they meet water of the same density.

Multiple rosette immersions have located them between 100 and 120 meters at temperatures of 0.8° C. The scientific interest is, of course, to find out which micro-organisms live in these “brines”. Are they a particular habitat for plankton? This is one of the main questions for sampling station no. 206.

We will remain at this scientific station in the fjord until tomorrow afternoon, a few miles from Uummannaq. Several hundred wooden houses of all colors are miraculously clinging to the rock. 1,400 Kalaallit** live here along with some Danish immigrants. It’s a paradise for dog sledding, and people say the best Greenland drivers are here in Uummannaq Bay.

At the base of this majestic bay also reigns the Qarajaq, one of the world’s fastest glaciers. It produces most of the icebergs that we’ve been admiring for the past 24 hours.

Vincent Hilaire

* Brines: Salt water with a higher concentration of salt.
** Kalaallit: Inuit inhabitants of Greenland (Kalaallit Nunaat)

Tara leaves Deception Island

On Tuesday morning we left the dormant volcano’s crater where we’ve been anchored for the last 3 days. The wind had died down, and the water was very clear and barely rippled. A couple of chinstrap penguins leapt out of the water around us. The ceiling of the sky was also much higher, which allowed us to see the circle of mountains buttressing the volcano.

Two cruise ships were at anchor, carrying out their customary shuttling of people back and forth in the dinghies to the nearest beaches, disembarking their batches of tourists. A soft yellow light bathed this peaceful lake.

As on our arrival, we left the island by the same route The cliffs at the northern entry this time appeared much less hostile than a couple of days ago when we “landed” here in windy conditions, high seas and a snow storm. Compared to the previous anchorage at Brown Bluff, we saw very few penguins at Deception Island.

We are now passing by Snow Hill Island and occasionally, on the port side, we can see misty tops of the peninsula. Both engines are running, one reef on the foresail but none on the mainsail. There’s very little wind barely measuring 6 knots. In the coming days we expect first a southwesterly flux, which will then turn north. 20 to 30 knots.

The door to the Antarctic closes behind us as we pass Snow Hill. While discussing on the bridge after dinner with Hervé Bourmaud, our captain, and Edouard Leymarie, one of the 6 researchers on board for this leg, both confided their wish to return and explore more the White Continent. Of the 14 on board, there are 13 of us who are here for the first time. Lots of images and memories are already turning about in our heads. Lots of new wishes also, like discovering the west coast of the peninsula which in the end we didn’t manage to see at all. Our time was running out.

We are getting ready to recross the Drake Passage. Our arrival at Port Williams is still scheduled for next Saturday. The forecasted winds in the Beagle Channel could make for a tricky arrival and anchoring.

 

Vincent Hilaire

Fossil Island

Marambio lies at latitude 64º06’South and longitude 56º41’West. We’ll have spent 20 hours anchored here. Yesterday evening, after we arrived, the surrounding mountains were dusted white with snow.

The trip on land today kept all its promises: the ground of Marambio is scattered with fossils and nesting arctic terns.

At the northern point of the island, a camp with some red and yellow tents. Four Argentinean and Spanish geologists are on mission for a month. Their camp is installed on a small plateau facing the sea. When we arrived yesterday evening, it was the surprise of the day for them. They have been here since December 22nd and will stay until January 25th. Their camp consists of several tents, one of which serves as a living base. It’s heated and there’s a table, chairs, a camp-stove and refrigerator – a place where they eat and work.

They are working for the Argentinean Antarctic Institute and the Spanish Geological and Mining Institute, mapping the island and doing a soil study. This island is very ancient: its formation dates back to the creation of the Antarctic Peninsula, when South America separated from the White Continent resulting in the creation of Drake Passage. Studying this island is thus of utmost importance to better understand this epoque dating back millions of years.

Sergio, Elisabet, Manuel and Francisco (aka “Paco”) served us tea and we talked for several minutes. They complained about the lack of sunshine since their arrival. Except for one or two days, they’ve had overcast and cold weather. It’s their 4th mission on Marambio. And like the times before, they arrived here by plane. On the plateau above their campground, there’s a runway which can accommodate big military transporters. Once they land and arrive at their chosen site, they have to set up camp composed of a dozen or so tents. They were glad about our visit – a real change from their routine.

Sergio is Argentinean from Buenos Aires, and remembers Tara’s former visit in 2005 when there were mountaineers aboard.

After this pleasurable meeting, it was time to get back on board. We left our anchorage in the mid-afternoon to return to the Antarctic Sound, where a new station, the fifth since we departed from Ushuaia, will take place in the coming hours. Most likely we’ll be at a new anchorage this evening, in front of the Argentinean base “Esperança”.

At the moment, the breakdown of the generator which runs the immersion winch has not been solved. Numerous telephone calls and emails to land-based specialists are being made in order to find the cause.

Vincent Hilaire