|Kaplan's SLP Data Set|
|Variable(s)||Sea Level Pressure|
|Land or Ocean||Ocean|
|Current Period of Record||4/1854-12/1992|
|Resolution||Monthly, Global, 4o x 4o|
|Description:||Reduced space optimal interpolation of COADS.|
|Reference:||Kaplan A., Y. Kushnir, M.A. Cane, 2000: Reduced space optimal interpolation of historical marine sea level pressure, J. Climate. 13, 2987--3002.|
|Data Set Location:||IRI/LDEO (International Research Institute for Climate Prediction / Lamont-Doherty Earth Observatory)|
|Technical Overview||Expert User Guidance||Relevant Articles||Coverage Maps|
Reduced Space Optimal Interpolation procedure has been applied to the global sea level pressure (SLP) record of COADS averaged on 4x4 grid. For more information about this data set please click here.
|Expert User Guidance|
A climate's permanence
Least squares procedures of optimal estimation, when applied to gappy and erratic data, result in the solutions which predominantly project onto the most energetic patterns of a priori error covariance. This property of the solution allows to combine the classical least squares technique with the approach of a space reduction in order to develop a computationally effective procedure of objective analysis for observed historical climate data. (Such data are characterized by comparatively precise observations and good coverage in the last few decades, and poor observational coverage prior.) An important aspect of our approach is that it also produces verifiable error bars for analyzed values. For details of the technique see Kaplan et al. 1997, for a simple qualitative introduction see Kaplan et al. 2001.
Here we applied the reduced space optimal interpolation technique to
the COADS sea level pressure (SLP) data set
(Woodruff et al. 1987,1993) and produced an analyzed data set
) which verifies surprisingly well by other data sources (particularly
NCEP NCAR Reanalysis) and against independent data (selected land station
records). The detailed description of this product and its
verification is given in Kaplan et al. 2000, but there are a few
points I feel compelled to make here:
Kalnay, E. et al., 1996: The NCEP/NCAR 40-year reanalysis project. Bull. Amer. Meteor. Soc., 77, 437-471.
Kaplan A., M.A. Cane, and Y. Kushnir, 2001: Reduced space approach to the optimal analysis interpolation of historical marine observations: Accomplishments, difficulties, and prospects, WMO Guide to the Applications of Marine Climatology, World Meteorological Organization, Geneva, Switzerland, in press; available at http://rainbow.ldeo.columbia.edu/~alexeyk/CLIMAR99/wmogr.ps
Kaplan A., Y. Kushnir, M.A. Cane, 2000: Reduced space optimal interpolation of historical marine sea level pressure, J. Climate. 13, 2987--3002.
Kaplan, A., Y. Kushnir, M. Cane, and M. Blumenthal, 1997: Reduced space optimal analysis for historical datasets: 136 years of Atlantic sea surface temperatures, J. Geophys. Res., 102, 27835--27860.
Woodruff, S.D., R.J. Slutz, R.L. Jenne, and P.M. Steurer, 1987: A comprehensive ocean-atmosphere data set. Bull. Amer. Meteor. Soc., 68, 1239-1250.
Woodruff, S.D., S.J. Lubker, K. Wolter, S.J. Worley, and J.D. Elms, 1993: Comprehensive Ocean-Atmosphere Data Set (COADS) Release 1a : 1980-92. Earth System Monitor, 4, No. 1, 1-8.
Click on the links below to view data coverage maps for a particular time period. Percentage of non-missing data per time period is plotted. Coverage is consistent throughout the period of record.