From above, the Arctic environment looks like a frozen waste.

Look down over the Arctic from high above and you will see nothing but a vast white expanse. There may be an occasional misty plume from a whale swimming between ice floes, a black dot where a seal has hauled out or a tiny polar bear almost invisible against the white snow.

But take a look beneath the water or into the ice itself and - with the right equipment - you will see billions of lifeforms teaming together in a microbial soup. Invisible to the naked eye, the microscopic life in the marine Arctic environment contains a complex and highly linked community of bacteria, viruses, protozoa, and other single-celled organisms relatively new to science.

These tiny creatures are the key players in the Arctic ecosystem: consumers of carbon and producers of compounds that pass up the food chain until they enter the stomachs of whales, polar bears and other top predators. If the microbial system changes dramatically, the costs to higher animals - and humans - could be severe. Therefore it is critical to identify today's Arctic communities and monitor their change as the Arctic climate shifts.

"WHY ARE WE SO INTERESTED IN CARBON FLOW IN THE ARCTIC?"

The Arctic is a small area - only 3% of the global ocean - and is a low primary production region with about 1% of global ocean productivity. So it doesn't appear to be an important carbon sink compared to other oceans.

I asked Dr Ray Leakey, our expedition leader and marine microbiologist, to explain...

OCEAN CURRENTS AND THE ARCTIC

Many people familiar with "The Gulf Stream" believe that this ocean current is responsible for the mild weather experienced in Western Europe and Britain. However, the circulation patterns in the Atlantic Ocean are rather more complex than this and the Gulf Stream accounts for only one small part of the process.

The most important driver of water flow through the Atlantic is actually the Arctic, where the formation of sea-ice concentrates salt into the upper ocean layer, increasing its density so much that it sinks to the sea floor. 

 Click here for MORE ON ARCTIC OCEAN CURRENTS...

CARBON AND THE ARCTIC ENVIRONMENT - the science of the expedition

The Arctic is the most rapidly warming region of the planet. On land the Greenland ice cap is melting, permafrost thawing and vegetation zones are moving north. In the ocean the summer sea-ice cover is shrinking and the underlying water becoming fresher due to increasing glacier melt and river flow. The reduction in sea-ice is dramatic: 2007 witnessed the greatest retreat of summer sea-ice since records began with a loss of... 

READ ON TO LEARN MORE ABOUT SEA-ICE CHANGE AND HOW THIS MAY AFFECT THE ARCTIC FOOD WEB & CARBON CYCLE...

THE QUESTIONS WE ARE INVESTIGATING

A number of different research areas are being investigated on this expedition. The major focus is on the fate of carbon entering the Arctic ecosystem, whilst other strands will investigate physical aspects of the ocean.

Microbial plants at the base of the food web
(Phytoplankton and primary production)

Microscopic plant life – the phytoplankton – grow in surface waters using the sun’s energy to photosynthesise. This process absorbs carbon from the environment and turns it into new plant material (biomass) – the first step in the organic carbon cycle. By measuring phytoplankton biomass and growth (primary production) – we can establish how much carbon and energy are available for all other organisms.
MORE ABOUT THE SCIENCE AND SCIENTIST…

Microbial animals – eating the microscopic plant life
(Heterotrophic microbes)

The sea is teaming with viruses, bacteria and protozoans. These organisms carry out three critical roles: they infect, they degrade and they eat. These processes are important because they lead to the rapid release of carbon back into the environment, stalling the transfer of carbon up the food web. By identifying and measuring their activity, we can work out just how much carbon is liberated at this early stage. MORE ABOUT THE SCIENCE AND SCIENTIST…

Some of the carbon is released into the atmosphere as methane and other important gases: we will measure this too. MORE ABOUT THE SCIENCE AND SCIENTIST…

Zooplankton – eating the microbes

These tiny crustacean (shrimp-like) animals graze on microbial life. They are the next step in the transfer of carbon and energy up the food web. In the Arctic, these animals are very effective at storing energy in their bodies in the form of fatty compounds called lipids - they have been likened to packets of butter. Zooplankton are therefore a key link in the transfer of energy from microbial life to the more familiar whales, fish, polar bears and seals.  MORE ABOUT THE SCIENCE AND SCIENTIST...

Using echo-sounders we will locate the zooplankton, sample them with nets then correlate the acoustic signal bouncing back from the swarm of plankton with the species in the nets. MORE ABOUT THE SCIENCE AND SCIENTIST...

The descent of carbon to the seafloor

Much of the carbon captured by plankton in the surface waters will end up on the seafloor. But how much? And how fast does it get there?
By placing sediment traps in the water column we will capture descending material. This can be analysed for changes in the ratio of naturally occurring radio-isotopes, which can reveal both the origin of the material (terrestrial or marine) and the time since it left surface waters. MORE ABOUT THE SCIENCE AND SCIENTIST…

How much carbon is locked away on the seafloor?

When organic debris reach the sea floor, some is consumed and recycled by benthic (bottom living) microbes, worms, brittlestars and other small animals whilst some carbon is buried and locked away over geological timescales. Using a mega-corer and benthic landers we will examine the balance between long-term carbon storage and recycling. MORE ABOUT THE SCIENCE AND SCIENTIST…

Palaeoclimate studies

The Arctic climate has shifted dramatically over geological time scales. To identify what past climates were like we need to understand the link between particular biological molecules still present in the geological record - biomarkers - and the organism in which they were originally found. For example, the presence of a compound called IP₂₅ - which is only produced by sea-ice algae - in the geological record would indicate that a particular region was ice covered in the past. MORE ABOUT THE SCIENCE AND SCIENTIST...

Plotting the sea floor

Detailed maps of the sea floor can be produced using multibeam bathymetry. A fan-shaped array of sound beams is bounced off the sea bed and the time is measured for the echoes to return to the ship. The repeated ‘snapshots’ of depth obtained as the ship progresses stack up to create bathymetric (bottom contour) maps. These are of great interest to various marine research groups – for example, physical oceanographers seeking to establish deep-water pathways, and palaeoclimate researchers investigating the limits and dynamics of vanished ice sheets in formerly glaciated regions. MORE ABOUT THE SCIENCE AND SCIENTIST…

Ocean currents

The transport of nutrients and carbon between shelf seas and the open ocean is a critical part of carbon and nutrient cycles.  Dense water formation and cascades at the shelf edge are thought to be important in forming some oceanic water masses.  It is also becoming evident that the shallow sea margins play previously unrecognised roles in the control of water circulation round the major ocean basins.  There remains a real challenge to link the contrasting physics of shelf and deep ocean environments across the steep bathymetry of the shelf slope. MORE ABOUT THE SCIENCE AND SCIENTIST...