710
Herterich et al.
called LGM. Further insights into the exact timing
ofthe LGM can be gained from the interaction of
ice-sheet modelling and ice core dating.
The last question to be addressed is how we
envision CLIMAP 2000 to proceed. To this end,
we suggest a three step undertaking. In a first step,
the Sonderforschungsbereich 261 at the University
of Bremen, in cooperation with the AlfredWegener-Institut, prepares the reconstruction of
the glacial South Atlantic circulation. At the same
time and independently the Sonderforschungsbereich 313 at the University ofKiel completes its
work on the glacial circulation of the northern North
Atlantic. In a second step, the two domains are
merged and proxy data and modelling results from
German terrestrial paleontologists are added. In the
final step, global maps may be produced within an
international framework, possibly the IMAGES
project. The cooperation with scientists from all
over the world is sought at an early stage.
Conclusions
In this article a new project is discussed which is
based on, but meant to go beyond CLIMAP. This
project is called CLIMAP 2000 and strives for a
global synthesis ofLGM data and modelling. The
possible share of modelling has been discussed in
detail. From the view-point of paleoclimate modelling, the new CLIMAP 2000 data base resulting
from this global synthesis should include:
I. A revised set of SSTs and a new set of SSSs.
2. Maps and sections of distributions of biogeochemically passive ocean tracers such as salinity,
8 18 0 or 14C.
3. A new ice-sheet reconstruction.
4. Rainfall and snowfall over continental ice-sheets.
S. Maps and sections of distributions of biogeochemically active ocean tracers such as Oi3C.
6. A vegetation map.
The contribution of paleoclimate modelling itself to
CLIMAP 2000 should be:
I. Generating global and detailed maps of climate
parameters which are insufficiently documented by
proxy data.
2. Checking consistency of proxy data, comparing
with simulated data on a point-by-point basis, e.g.
atmospheric and ocean models can point towards
erroneous observations.
3. Interpolating sparse data utilizing physical principles, e.g. with the help of inverse ocean and vegetation models.
4. Extrapolating into areas where no proxy data are
available, e.g. the North Pacific.
S. Depicting climate parameters for which there
are no proxy data.
Acknowledgments
The authors kindly acknowledge financial support
from various funding agencies: The Deutsche
Forschungsgemeinschaft (DFG) supports Michael
Matthies, Andre Paul and Reiner Schlotte within
the Sonderforschungsbereich 261 (Der Siidatlantik
im Splitquartlir, Teilprojekt C2) and Imke Hansen
within the Coordinated Program Antarctic Research. Phillip Helbig, Stephan Lorenz and Ulrike
Wyputta receive funds from the German climate
research program (BMBF, 03FO 131A) and Stephan
Determann from the German JGOFS program
(BMBF, 03F0160C). The atmospheric and oceanic
modelling work is supported by PMIP, which is
endorsed by PAGES IIGBP and WGNE I WCRP,
where we receive funds from EC contract ENV 4CT9S-007S. Bjorn Grieger, Klaus Herterich and
Andreas Manschke belong to the staff of the
paleoceanographic modelling group of the Fachbereich S, paid by the University of Bremen.
The models ECHAM, LSG and HAMOCC
have been developed and put at our disposal by the
Max-Planck-Institut flir Meteorologie and the
Deutsches Klimarechenzentrum, Hamburg. The
inverse ocean model on which 2RAIOM is based
was originally developed by Reiner Schlitzer. The
Antarctic ice-sheet model is developed in the frame
of the project "Marine Ice-sheet Motion" belonging to the DFG.
A. P. highly appreciates the long-term cooperation with Dan Seidov. Furthermore he wishes to
thank Christian Schlifer-Neth for his valuable advice in reconstructing glacial sea surface salinities
for the northern North Atlantic.We would like to
Herterich et al.
called LGM. Further insights into the exact timing
ofthe LGM can be gained from the interaction of
ice-sheet modelling and ice core dating.
The last question to be addressed is how we
envision CLIMAP 2000 to proceed. To this end,
we suggest a three step undertaking. In a first step,
the Sonderforschungsbereich 261 at the University
of Bremen, in cooperation with the AlfredWegener-Institut, prepares the reconstruction of
the glacial South Atlantic circulation. At the same
time and independently the Sonderforschungsbereich 313 at the University ofKiel completes its
work on the glacial circulation of the northern North
Atlantic. In a second step, the two domains are
merged and proxy data and modelling results from
German terrestrial paleontologists are added. In the
final step, global maps may be produced within an
international framework, possibly the IMAGES
project. The cooperation with scientists from all
over the world is sought at an early stage.
Conclusions
In this article a new project is discussed which is
based on, but meant to go beyond CLIMAP. This
project is called CLIMAP 2000 and strives for a
global synthesis ofLGM data and modelling. The
possible share of modelling has been discussed in
detail. From the view-point of paleoclimate modelling, the new CLIMAP 2000 data base resulting
from this global synthesis should include:
I. A revised set of SSTs and a new set of SSSs.
2. Maps and sections of distributions of biogeochemically passive ocean tracers such as salinity,
8 18 0 or 14C.
3. A new ice-sheet reconstruction.
4. Rainfall and snowfall over continental ice-sheets.
S. Maps and sections of distributions of biogeochemically active ocean tracers such as Oi3C.
6. A vegetation map.
The contribution of paleoclimate modelling itself to
CLIMAP 2000 should be:
I. Generating global and detailed maps of climate
parameters which are insufficiently documented by
proxy data.
2. Checking consistency of proxy data, comparing
with simulated data on a point-by-point basis, e.g.
atmospheric and ocean models can point towards
erroneous observations.
3. Interpolating sparse data utilizing physical principles, e.g. with the help of inverse ocean and vegetation models.
4. Extrapolating into areas where no proxy data are
available, e.g. the North Pacific.
S. Depicting climate parameters for which there
are no proxy data.
Acknowledgments
The authors kindly acknowledge financial support
from various funding agencies: The Deutsche
Forschungsgemeinschaft (DFG) supports Michael
Matthies, Andre Paul and Reiner Schlotte within
the Sonderforschungsbereich 261 (Der Siidatlantik
im Splitquartlir, Teilprojekt C2) and Imke Hansen
within the Coordinated Program Antarctic Research. Phillip Helbig, Stephan Lorenz and Ulrike
Wyputta receive funds from the German climate
research program (BMBF, 03FO 131A) and Stephan
Determann from the German JGOFS program
(BMBF, 03F0160C). The atmospheric and oceanic
modelling work is supported by PMIP, which is
endorsed by PAGES IIGBP and WGNE I WCRP,
where we receive funds from EC contract ENV 4CT9S-007S. Bjorn Grieger, Klaus Herterich and
Andreas Manschke belong to the staff of the
paleoceanographic modelling group of the Fachbereich S, paid by the University of Bremen.
The models ECHAM, LSG and HAMOCC
have been developed and put at our disposal by the
Max-Planck-Institut flir Meteorologie and the
Deutsches Klimarechenzentrum, Hamburg. The
inverse ocean model on which 2RAIOM is based
was originally developed by Reiner Schlitzer. The
Antarctic ice-sheet model is developed in the frame
of the project "Marine Ice-sheet Motion" belonging to the DFG.
A. P. highly appreciates the long-term cooperation with Dan Seidov. Furthermore he wishes to
thank Christian Schlifer-Neth for his valuable advice in reconstructing glacial sea surface salinities
for the northern North Atlantic.We would like to