TRAINING SESSION ON HOMOGENISATION METHODS

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TRAINING SESSION ON HOMOGENISATION METHODS
Inhomogeneities in global datasets
Bologna, 17th-18th May 2005
Maurizio Maugeri, University of Milan
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Inhomogeneities in Re-Analyses
It is to be noticed that also the most widely
used globala data-sets (e.g. NCEP reanalyses) are
affected by significant biases
NCEP US National Center for Environmental
Predictions
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NCAR/NCEP RE-ANALYSIS
Sturaro G., 2003 A closer look at the
climatological discontinuities present in the
NCEP/NCAR reanalysis temperature due to the
introduction of satellite data, Climate
Dynamics, 21, 309-316.
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NCAR/NCEP RE-ANALYSIS
NCAR/NCEP RE-ANALYSIS
Sturaro G., 2003. A closer look at the
climatological discontinuities present in the
NCEP/NCAR reanalysis temperature due to the
introduction of satellite data, Climate
Dynamics, 21, 309-316.
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NCAR/NCEP RE-ANALYSIS
NCAR/NCEP RE-ANALYSIS
Sturaro G., 2003. A closer look at the
climatological discontinuities present in the
NCEP/NCAR reanalysis temperature due to the
introduction of satellite data, Climate
Dynamics, 21, 309-316.
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NCAR/NCEP RE-ANALYSIS
NCAR/NCEP RE-ANALYSIS
Very good to study daily variability and to
capture atmospheric circulation features
Not good to study climate trends and to describe
long-term evolution
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ITALIAN SLP
NCAR/NCEP RE-ANALYSIS Italian SLP
NCAR/NCEP Re-analysis
UK Met Office
M. Maugeri, M. Brunetti, F. Monti, T. Nanni.
2003. The Italian air force sea level pressure
data set (1951-2000). Il Nuovo Cimento, 26C,
453-467.
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NCAR/NCEP RE-ANALYSIS
NCAR/NCEP RE-ANALYSIS
CRADDOCK TEST BETWEEN ITALIAN SLP AND RE-ANALYSIS
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UKMO
NCAR/NCEP RE-ANALYSIS
CRADDOCK TEST BETWEEN ITALIAN SLP AND UK MET
OFFICE SLP
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NCEP-ECMWF-MSU
We do not know which of the data set (if any) is
correct. There is, however, evidence that
inhomogeneities can be identified in both
reanalysis, but this does not imply that there
are no problems with the MSU
Stendel et al. 2000, Assessing level of
uncertainty in recent temperature time series,
Climate Dynamics, 16, 587-601.
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Stendel et al. 2000, Assessing level of
uncertainty in recent temperature time series,
Climate Dynamics, 16, 587-601.
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Inhomogeneities in Re-Analyses
Stendel et al. 2000, Assessing level of
uncertainty in recent temperature time series,
Climate Dynamics, 16, 587-601.
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Inhomogeneities in Re-Analyses
Stendel et al. 2000, Assessing level of
uncertainty in recent temperature time series,
Climate Dynamics, 16, 587-601.