* Astronomy

More than 8,600 km² of ocean floor mapped, 31 metres of ocean sediment extracted and almost 3,345 nautical miles of navigation through Arctic waters. To mark the 125th anniversary of the 1st International Polar Year, the University of Barcelona has carried out this research project in the north of the Arctic Circle to study natural climate change and the evolution of the Arctic continental margin. These are some of the details recorded in the log of the SVAIS expedition for the International Polar Year (IPY), funded by the Spanish Ministry of Education and Science. On board the BIP Hespérides, a scientific research ship belonging to the Spanish navy, the expedition spent the boreal summer studying records of natural climate change and the relief of the ocean floor in the Fram Straight an area in which the cold waters of the Arctic Ocean come into contact with the warmer waters of the Atlantic from three million years ago to the last deglaciation, between 20,000 and 10,000 years ago.
The expedition set sail on 29 July from the island of Spitzberg in the Svalbard Archipelago (Norway), a traditional whaling area situated only 1,338 kilometres from the North Pole. Under the midnight sun, the boat set a course for the Storfjorden Trough, a little known area on the southeast edge of the Svalbard Islands, dominated in the past by large ice streams that have shaped the topography of the ocean floor.

The Polar Regions: endangered areas
The Arctic is the closest polar area to us and is much more sensitive to climate change than the Antarctic, with the exception of the Antarctic Peninsula, explained Angelo Camerlenghi, a geologist with the Marine Geoscience Research Group at the UB, research professor at the Catalan Institute for Research and Advanced Studies (ICREA) and the scientific director of the SVAIS expedition. The Poles are the motors of the worlds ocean circulation; they reflect solar radiation and help to lower global temperatures. In addition, the Polar Regions provide unique information on the history of our planet and store climate records dating back millions of years. The Arctic is a delicate environmental sensor that highlights the effects of climate change.

Climate change has a more dramatic effect at the Poles. The glaciers are receding and we are beginning to see that climate changes in the past have had other very significant effects on our planet - geologist Roger Urgelès.

Scars on the ocean floor
On board ship, work continued uninterruptedly during the crossing of the Barents Sea. In order to maintain activity 24 hours a day, the team worked shifts in groups coordinated by the geologists Galderic Lastras, Ben de Mol and Roger Urgelès, under the supervision of Angelo Camerlenghi and Miquel Canals. The objective was clear: to determine the evolution of the polar continental margins in this region of the Arctic and to study the topography of the ocean floor.

We want to examine the sediments transported by the large ice streams that flowed across the Arctic 20,000 years ago, during the last glacial maximum, to understand the intensity and the duration of climate processes originated by the Poles - Professor Antoni Calafat.

Day by day the sonar screens revealed icebergs, old glaciers and the scars of submarine avalanches that had disturbed the calm of the ocean depths. On deck, the grey of the sky merged with the water and the light of the Arctic sun at times disorientated the team.

Mapping the ocean depths
Only 10% of the worlds ocean floor has been mapped in detail.

There are still many ocean regions across the world that need to be mapped. We use multibeam and TOPAS echosounders to transform the sound waves reflected by the ocean floor into bathymetric information - Miquel Canals, head of the Marine Geosciences Research Group at the UB.

In addition to multibeam bathymetry, the seismic reflection technique can also be used to produce topographic maps of the Arctic Ocean floor: special airguns send seismic waves to the ocean floor, which are reflected and recorded at the surface by hydrophone arrays fitted in cables known as streamers. The data information is processed to control for quality and then converted into 3D maps of the ocean topography using a specialised program known as the KINGDOM Suite. Shrouded in fog, the ship sailed through areas likely to contain oil or gas hydrates molecules of gases such as methane trapped in crystalline structures of water molecules, and thought to be the great energy reserve for the future.

Although they were discovered years ago, we still do not have the technology to extract gas hydrates - geologist Ben De Mol.

Ocean sediment dating back 10,000 years
One of the most eagerly anticipated moments took place on 4 August: on what proved to be an exciting day, the first samples of sediment from the ocean floor were raised onto the deck of the research vessel using the Piston Corer, a new hydraulic coring device for extracting marine sediment designed by Oregon State University and the Marine Technology Unit of the CSIC. During the expedition, the Piston Corer was used to obtain six samples of ocean sediment, which represent a total of 31 metres of geological history from the glacial and interglacial periods of the Quaternary Period in the Fram Strait. In the laboratory on the starboard side of the ship, the Marine Geosciences Research Group of the University of Salamanca conducted the first study of the cores extracted from the ocean floor.

We identify the microfossils foraminifera and coccolithophorida to determine an initial time scale of the sedimentary strata, which allows us to create a palaeoenvironmental reconstruction of the Arctic -  palaeontologist José Abel Flores.

On 17 August, after 20 days sailing through ice-free waters, the BIO Hespérides finally docked in Longyearbyen. This brought the polar expedition to an end, but the work of the scientific team will continue for several months. They will examine the material obtained to extract scientific data relevant to different fields of study (such as biostratigraphy, sedimentology, palaeoclimatology and environmental geomagnetism) and reconstruct the geological and climatic history of the Arctic region.

The most northerly geological research project
The SVAIS expedition team comprised 21 scientists, including seven predoctoral students, four journalists, two high-school teachers and five technicians from the Marine Technology Unit of the Spanish National Research Council (CSIC). The team was based on the BIO Hespérides, a Spanish navy research vessel with a crew of 55, captained by Commander Luis de la Puente. The institutions taking part in the project are the UB, the ICREA, the Chemical and Environmental Research Institute of Barcelona (IIQAB-CSIC), the University of Salamanca, the National Institute of Oceanography and Experimental Geophysics (OGS) of Trieste and the Universities of Svalbard and Tromsø (Norway).

Source