[graffis-l] LIFE IN THE SOUTHERN OCEAN & CLIMATE CHANGE

November 30, 2007

Life In The Southern Ocean & Climate

Change

Posted by: " Mark Graffis "

mgraffis

Thu Nov 29, 2007 9:25 am (PST)

http://www.enn.com/ecosystems/article/26129

Alfred Wegener Institute for Polar and Marine Research. Published November 29, 2007 11:26 AM Life In The Southern Ocean & Climate Change

A ten-week expedition to the Lazarev Sea and the eastern part of the

Weddell Sea opens this year's Antarctic research season of the German

research vessel Polarstern. On the evening of November 28, just some two

hours after an official ceremony at the Berlin Museum of Natural History

honouring Polarstern's 25th anniversary of service, the research vessel

will begin its 24th scientific voyage to the Southern Ocean from Cape

Town.

The 53 scientists from eight nations aboard Polarstern will focus

much of their work on climate-related research as part of the

International Polar Year. In addition, Polarstern will also supply the

German Neumayer Station during the first leg of the trip, and accompany

the freighter 'Naja Arctica' which will deliver construction materials

for the new research station Neumayer III to the Antarctic. On February

4, 2008, Polarstern is expected to return to Cape Town.

" Our research projects will improve the understanding of

physical and biological processes associated with the Antarctic

Circumpolar Current and the Weddell Gyre, both of which play a key role

for the earth's climate " , explains chief scientist Prof Dr Ulrich

Bathmann of the Alfred Wegener Institute for Polar and Marine Research in

the Helmholtz Association, referring to the central goal of the

expedition.

Plankton algae from these two marine currents south of the Atlantic

Ocean are absorbing significant amounts of the climate gas carbon dioxide

through their growth during the summer. By sinking to the Antarctic deep

sea, these algae are subsequently transferring the carbon dioxide to the

seafloor, where, in some cases below 4000 meter water depth, they provide

food for bottom dwelling organisms. " The efficiency of this

biological pump is controlled, for example, by nutrients, by physical

dynamics in the ocean surface layer, and by the species of algae

involved " , says Bathmann. " We have to investigate these complex

interactions further, in order to optimise scientific climate

predictions. "

The region covered by Polarstern during this mission extends from 40

to 70 degrees southern latitude, i.e. from the so-called subtropical

convergence, a hydrological boundary separating the Antarctic from the

Atlantic Ocean, and the Antarctic continent. The scientific studies

aboard Polarstern, aside from being highly relevant for climate research,

are part of three large international programmes within the International

Polar Year framework.

The research programme SCACE (Synoptic Circum-Antarctic Climate and

Ecosystem Study) explores physical and biological interrelations in the

Antarctic Circumpolar Current, comparing recently recorded parameters

with historical data. " The Antarctic Circumpolar Current measures

several hundred kilometres across, surrounding the Antarctic continent

and connecting all large oceans " , explains Ulrich Bathmann.

" This large ocean current transports both heat energy and fresh

water, plays a central role in the ocean-wide cycles of dissolved

material, and contains a series of distinct ecosystems that may displace

each other with changing climate regimes. Plankton algae involved have a

high potential for absorbing atmospheric carbon dioxide " , the marine

biologist adds about the significance of the Antarctic Circumpolar

Current for the functioning of the system Earth.

At the same time, Southern Ocean natural systems themselves are

extremely sensitive to global changes. Hence, one of the central tasks of

the SCACE programme will consist in collecting a unique data set that can

serve as a benchmark for comparison with existing data to identify and

quantify polar changes.

A special role for food webs in the Southern Ocean is played by

krill. This group of crustaceans, which may also become interesting for

economic purposes, has been relatively well studied in some few regions

of the Antarctic, for instance surrounding the Antarctic Peninsula.

However, as some of the results revealed, the krill's seasonal survival

mechanisms show large regional variation, so extrapolations from local

studies to a wider area are hardly possible. For this reason, the

research project LAKRIS (Lazarev Sea Krill Study) will be a detailed

investigation into the life cycle, distribution and physiology of krill

populations in the Lazarev Sea.

According to existing information, krill is very abundant in this

area. " In this case also, our primary question of interest is the

krill's ability to adapt to potential environmental changes " ,

explains Ulrich Bathmann the connection to climate research. The LAKRIS

study will complement similar large-scale investigations in other regions

of the Antarctic.

While the continental shelf regions surrounding Antarctica are

relatively well known, the Antarctic deep sea remains practically

unexplored. Large areas of the seafloor around Antarctica, however, are

deep-sea environments. Led by Prof Dr Angelika Brandt of the Zoological

Institute of the University of Hamburg the third expedition project,

ANDEEP-SYSTCO, tries to shed light on this unknown world. The acronym

envelops an Antarctic deep-sea research programme, exploring various

regions of the Southern Ocean at several thousand meters of depth with

the primary goal of analysing interactions among atmosphere, water column

and seafloor.

" Since deep sea research continues to take us to unknown worlds,

we are expecting some new and fascinating insights regarding biological

diversity in the ocean, perhaps even the discovery of previously unknown

species " , explains Bathmann. The Polarstern expedition thus is part

of two major global research initiatives studying marine biodiversity:

the 'Census of Antarctic Marine Life' (CAML), and the 'Census of the

Diversity of Abyssal Marine Life' (CeDAMar), both of which are

sub-programmes of the so-called 'Census of Marine Life'.

(CeAt 09:27 AM 11/30/07, you wrote:

Life In The Southern Ocean &

Climate Change

Posted by: " Mark Graffis " mgraffis

mgraffis

Thu Nov 29, 2007 9:25 am (PST)

http://www.enn.com/ecosystems/article/26129

Alfred Wegener Institute for Polar and Marine Research.

Published November 29, 2007 11:26 AM

Life In The Southern Ocean & Climate Change

A ten-week expedition to the Lazarev Sea and the eastern part of the

Weddell Sea opens this year's Antarctic research season of the German

research vessel Polarstern. On the evening of November 28, just some two

hours after an official ceremony at the Berlin Museum of Natural History

honouring Polarstern's 25th anniversary of service, the research vessel

will begin its 24th scientific voyage to the Southern Ocean from Cape

Town.

The 53 scientists from eight nations aboard Polarstern will focus much of

their work on climate-related research as part of the International Polar

Year. In addition, Polarstern will also supply the German Neumayer

Station during the first leg of the trip, and accompany the freighter

'Naja Arctica' which will deliver construction materials for the new

research station Neumayer III to the Antarctic. On February 4, 2008,

Polarstern is expected to return to Cape Town.

" Our research projects will improve the understanding of physical

and biological processes associated with the Antarctic Circumpolar

Current and the Weddell Gyre, both of which play a key role for the

earth's climate " , explains chief scientist Prof Dr Ulrich Bathmann

of the Alfred Wegener Institute for Polar and Marine Research in the

Helmholtz Association, referring to the central goal of the expedition.

Plankton algae from these two marine currents south of the Atlantic Ocean

are absorbing significant amounts of the climate gas carbon dioxide