Gridded Global Last Glacial Maximum Sea Surface Temperature and Salinity Reconstruction: Readme file
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                   NOAA Paleoclimatology Program
                               and
            World Data Center for Paleoclimatology, Boulder
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!


NAME OF DATA SET: Gridded Global LGM SST and Salinity Reconstruction

LAST UPDATE: 7/2003 (Original Receipt by WDCA Paleo)  

CONTRIBUTORS: Christian Schäfer-Neth and André Paul, University of Bremen


IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2003-046

SUGGESTED DATA CITATION: Schäfer-Neth, C. and A. Paul, 2003,
Gridded Global LGM SST and Salinity Reconstruction, 
IGBP PAGES/World Data Center for Paleoclimatology, Boulder 
Data Contribution Series #2003-046. 
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. 


ORIGINAL REFERENCES: Paul, A. and C. Schäfer-Neth, 2003, 
Modeling the water masses of the Atlantic Ocean at the 
Last Glacial Maximum, Paleoceanography, Vol. 18, No. 3, 1058
doi: 10.1029/2002PA000783.
This paper details the 'line' version of the data set (see below).

Schäfer-Neth, C. and A. Paul, The Atlantic Ocean at the last glacial maximum: 
1. Objective mapping of the GLAMAP sea-surface conditions, in:
G. Wefer, S. Mulitza, and V. Ratmeyer (eds)
The South Atlantic in the Late Quaternary: Material Budget and Current Systems, 
Springer-Verlag, Berlin, Heidelberg, 2003, in press.
This publication describes the 'core' version of the data set (see below).


ADDITIONAL REFERENCES:
Sarnthein, M., et al., 2003,
Overview of Glacial Atlantic Ocean Mapping (GLAMAP 2000), 
Paleoceanography, 18(2), 1030, doi:10.1029/2002PA000769.

Pflaumann, U., et al., 2003,
The Glacial North Atlantic: 
Sea surface conditions reconstructed by GLAMAP 2000, 
Paleoceanography, 18, doi:10.1029/2002PA000774


FUNDING SOURCE: Deutsche Forschungsgemeinschaft (DFG), Germany

GEOGRAPHIC REGION: Global Ocean
PERIOD OF RECORD: Last Glacial Maximum, 19-22 cal.KYrBP

LIST OF FILES: readme.txt (this file), 8 ZIP data files with naming convention
and contents as follows:

lgmsst_V.zip ....... SST, degrees Celsius,
lgmsss_VW.zip ...... SSS, practical salinity units,
                     with V = "l" or "c",
                     and W = "0", "5", or "1"

                     each containing twelve files:

lgmsst_V_MM.xyz .... SST,
lgmsss_VW_MM.xyz ... SSS,
                       with MM = "01", "02", ..., "12"
 
Each data file provides a three-column tab-delimited table of 
longitude, latitude, and temperature/salinity on a regular 1 by 1 
degree grid. Land points are flagged by a value of -9999 and 
sea ice is indicated by a temperature of -1.8.

V = "l" or "c" indicates the "line" and "core" versions, respectively.

MM denotes the month: "01" = January, "02" = February, ...

W represents the magnitude of the additional Weddell Sea salinity 
anomaly: "0" = no anomaly, "5" = 0.55 salinity units, and "1" = 1 unit.

DESCRIPTION:

The recent efforts of the paleoceanographic community have
resulted in a unique set of reconstructed sea-surface temperature 
for the Atlantic Ocean during the Last Glacial Maximum, plus estimates 
for the extents of glacial sea ice (Sarnthein et al. 2003). Unlike
prior attempts, the contributing research groups based their data on
the definition of a common LGM chronozone and used the same modern
reference data for calibrating the different transfer techniques.
Furthermore, the number of processed sediment cores has been vastly
increased. Thus the new data is a significant advance not only with
respect to quality, but also to quantity.

We integrated these new data and provide monthly data sets of global
sea-surface temperature and ice cover, objectively interpolated by
variogram analysis and kriging to a regular 1°x1° grid, suitable for
forcing or validating numerical ocean and atmosphere models. These
gridded fields are available in two flavours: The 'line' version is
based on the LGM SST isolines provided by Plaumann et al. (2003),
whereas the 'core' version employed the SST estimates at the
individual core sites. 

In addition, we reconstructed sea surface salinity from the new
temperature data and the available oxygen isotope measurements with
three different salinity anomalies in the Weddell Sea (0, 0.55, and 
1.0 salinity units).