A good opportunity for model evaluation is provided by reanalyses employing numerical weather prediction models to convert irregularly spaced observational data into complete global, gridded, and temporally homogeneous data (presently available for periods of several decades). ❋ Unknown (2009)
Time series obtained from reanalyses are subject to inhomogeneities resulting from changes in the input data over multi-decadal timescales, while trends computed using station data are complicated by measurement errors. ❋ Unknown (2009)
The quality of precipitation climatologies for high latitudes derived from reanalyses is lower than that for temperature (or, e.g., atmospheric pressure). ❋ Unknown (2009)
However, despite these problems, reanalyses provide the best gridded, self-consistent datasets available for model evaluation. ❋ Unknown (2009)
The differences between the NCEP/NCAR and ECMWF reanalyses over land follow the NCEP/NCAR minus CRU differences in most, but not all, respects. ❋ Unknown (2009)
The ECMWF reanalysis is only available for the period since 1979; the difference between the ECMWF and NCEP/NCAR reanalyses shown in Fig. 4.2 was calculated for the overlapping interval (1979 – 1993). ❋ Unknown (2009)
Neither of the two reanalyses should be considered as "truth" but their differences provide some information about the probable magnitude of errors in them. ❋ Unknown (2009)
It is worthwhile noting that direct point-to-point and time-step-to-time-step comparison of a climate GCM output against observations, reanalyses, or another climate model simulation is not methodologically correct. ❋ Unknown (2009)
Observational data and reanalyses for model evaluation ❋ Unknown (2009)
Seasonal and annual mean differences in surface air temperature (a) between the NCEP/NCAR reanalysis and the CRU dataset for the period 1961 to 1990 and (b) between the NCEP/NCAR and the ECMWF reanalyses for the period 1999 to 1993. ❋ Unknown (2009)
This section examines Northern Hemisphere circulation using the National Centers for Environmental Prediction/National Center for Atmospheric Research reanalyses for the period from 1952 to 2003 [4]. ❋ Unknown (2009)
† The most enthusiastic of these reanalyses consists of data from over 6,000 farmers who were interviewed in twenty-three different research studies; each of these original investigators provided their data to Cancian 1976b. ❋ Everett M. Rogers (1995)
These recent reanalyses of the drug di fusion data illustrate how several scholars, each with a unique theoretical model and with distinctive methodological tools, come to different conclusions about the way in which network influences explain the adoption of an innovation. ❋ Everett M. Rogers (1995)
I understand the complaints about not having a long enough dataset to deduce trends, but we have around 30 years of “good” global best-tracks, buttressed by satellite technology, model reanalyses, and aircraft/military recon. ❋ Unknown (2007)
I am unconvinced that pre-satellite era tropical winds in the reanalyses have that much skill. ❋ Unknown (2007)
NCEP (and ERA) reanalyses are less reliable prior to 1979 owing to the lack of satellite temperature and humidity profiles, this is a well accepted statement (and a point that Ryan Maue raised earlier). lucia ❋ Unknown (2007)
Although reanalyses are dependent on VOS, constituting an important part of data assimilation input, it is assumed that the reanalysis fields adequately reproduce synoptic variability at the sea surface. ❋ Unknown (2007)
Sampling errors estimated from different reanalyses and from seasonal forecasts yield qualitatively comparable spatial patterns, in which the actual values of uncertainties are controlled by the magnitudes of synoptic variability. ❋ Unknown (2007)
Behavior of tropopause height and atmospheric temperature in models, reanalyses, and observations: Decadal changes ❋ Unknown (2007)
The studies finding a large urbanisation effect Kalnay & Cai, 2003, Zhou et al., 2004 are based on comparison of observations with reanalyses, and assume that any difference is entirely due to biases in the observations. ❋ Unknown (2007)
