Frequently Asked Questions

ACEX Frequently Asked Questions
What is the Arctic Coring Expedition?
Scientists from around the world want to study sediments from beneath the Arctic Ocean seafloor to allow them to reconstruct the climate history of this ocean over the last 50 Million years. This should help us to understand the processes that led to the Northern Hemisphere Pleistocene Ice Age. The Arctic Ocean is a major gap in the datasets we have on Earth's past climate with no almost data collected there at all.

Where is the Lomonosov Ridge?
This Lomonosov Ridge is a subsea mountain chain which crosses the Arctic Ocean from Greenland to Siberia, passing close to the North Pole. Although the top of the ridge is far below sea level (around 800 metres at the shallowest point) the ocean basins on each side of the ridge are much deeper, up to 4 kilometres deep in places. This means that the Lomonosov Ridge stand as high above the surrounding ocean basins the top of the Alps do above western Europe. However the ridge is flat-topped rather than peaked. The first choice drill site is at 87º 40' N, just 250 kilometres from the North Pole.

Have ocean sediments been used to study earth's past climate in other parts of the world?
Yes, the Ocean Drilling Program (ODP), which ran from 1985 to 2003, has collected sediment cores from across the Earth's oceans. These have allowed scientists to understand the changes in Earth's climate for much of the last 50 million years. Detailed studies have been made of these changes in every oceans except the Arctic. No one has ever been able to collect deep core samples like these in the Arctic before.

Why has no one collected these samples here before?
Because the Arctic Ocean is covered year round in thick sea ice, which moves at a rate of a few kilometres a day. Average day time temperatures are below zero celsius all year round. This is about the most hostile place on Earth to conduct scientific research.

So why drill there rather than somewhere else or somewhere easier ?
The role of the Arctic in the Earth's climate systems is very poorly understood. Any models you might have seen showing what the climate of the Arctic was like in the past are based, largely on educated guesswork. However, we do know from cores collected in the Atlantic and Pacific Oceans that changes in the Arctic's climate and the Arctic Ocean must have affected the Earth's climate through the last 50 million years, we just don't understand this process in detail.

So why is the Lomonosov Ridge the best site?
The Lomonosov Ridge is a piece of the ocean floor that has been undisturbed for a very long time. Sediments appears to have been steadily collecting on this ridge for the last 50 million years without any breaks. This should allow us to collect a continuous record of earth's climate through this period in one of Earth least understood zones. The Lomonosov Ridge is also a long way from any major source of sediment input (like a major river or glacier) which could have contaminated this sequence.
Has anyone ever collected core here before?
More than 500 shallow cores have been collected in the Arctic Ocean, mostly less than 5 metres in length, (the longest is around 17 metres long). This means that the geology at the ocean floor itself is reasonably will known but at any depth the geology is almost completely unknown.

Has anyone ever tried to collect deep cores before?
There has been only one serious attempt made to core deep into the crust here. In 1996 the Swedish Polar Research Secretariat equipped the icebreaker Oden with a small rig and tried to core on the Lomonosov Ridge. However there were problems with the drilling system, which was not ideal, as it used plastic liners which proved to be too weak for the water depths. Also Oden was acting as both icebreaker and drillship so had to stay on the drill site and could not ram the heavier ice floes.

The current expedition plan was created by the same scientists involved in that project based on their experience and incorporating all the lessons learned into the plans. The technical problems will be solved by using multiple ships and a more robust drilling system. By having a drillship with two support ice breakers available for ACEX we hope to be able to drill in heavier ice conditions and increase the operational window.

Why is there a need to drill oceanic sediment cores when ice cores have been drilled in Greenland?
Ice cores can tell you in very great detail what has happening at the time that the snow fell that made up the ice. However, the oldest ice cores from Greenland are about 250,000 years old, only from the last part of the Pleistocene Ice Age, so ice cores alone can tell you nothing about the conditions in the Northern Hemisphere during the early stages of the ice age or before it began. If you want to study climate history before the ice records began the only accurate records come from ocean sediments. Remember we want to study the last 50 million years of climate history, which is more than200 times older than the oldest of the Greenland ice cores!

Who is paying for this?
The funding comes from contributions collected together from government science funding organisations in 13 European nations who have formed the European Consortium for Ocean Research Drilling (ECORD). ECORD was formed to allow European nations to cooperate to help IODP achieve its scientific objectives and it's members countries are currently: Denmark, Finland, France, Germany, Iceland, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland & the UK. Canada are currently negotiating to join; scientists in Austria, Belgium, Greece, Ireland and Turkey have also expressed interest.

A number of ECORD nations are making additional contributions to help the ACEX operation happen this year. Sweden is also supplying an additional contribution to the operation by providing ECORD with extra funding for ship time on the icebreaker Oden.

How can I follow the operation?
Regular updates will be put here on the expedition website.

How can I find out the results?
Some initial results may be announced at the end of the cruise but only a very small part of the analysis will be possible at sea. The really detailed scientific description will be done by an larger group of international scientists (the "science party") in the labs of the University of Bremen, Germany during November 2004. Here they will undertake very detailed description of the cores and their properties.
After this the science party will have another 12 months to go back to their own labs to do even more detailed research on the samples before the initial cruise information is published. Detailed scientific work will be published into scientific journals from this time into the future.
All of the basic data about the cruise will be available without charge on IODP websites from around the end of 2005. Also after one year the cores will be available to be sampled for research purposes by any interested and suitably qualified scientist from an IODP member country.