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distributed in time and space. Despite this difference the patterns in the two sets of mapsare remarkably similar. The drifter velocities are distinctly stronger in the AntarcticCircumpolar Current, the western boundary currents and the equatorial zone of the IndianOcean. The zonal velocities in the equatorial zones of the Atlantic and Pacific are similarin the CFSR and drifter maps although the drifter velocities are more divergent in thecold tongue region of the eastern Pacific.In Figure 55, the first two EOFs of the CFSR sea surface height (SSH) are shown at thetop and for satellite altimeter data from TOPEX/Jason-1 in the middle. The EOFs werecomputed for the period 1993-2008, the period for which TOPEX/Jason-1 data areavailable. The principal components in the bottom panel represent the temporalvariability of the two EOFs. The first EOF for CFSR and TOPEX/Jason-1 datarepresents the warm phase of ENSO, as is indicated by the maximum value in 1997,while the second EOF represents the cold phase of ENSO, as indicated by its maximumvalue in 1998. The first two EOFS for CFSR SSH are very similar to that for upper oceanheat content (not shown), reflecting the dominance of the thermosteric variability of SSHover other physical processes. While the CFSR and TOPEX/Jason-1 data showremarkable similarity (considering that TOPEX/Jason-1 data are not assimilated inCFSR), the major difference is the double maximum found in the spatial plot of the firstEOF when compared to TOPEX/Jason-1. Also, the first EOF represents only 32% of thevariability in CFSR compared to 42% for TOPEX/Jason-1. The second EOF is verysimilar for both CFSR and TOPEX/Jason-1.11. Concluding RemarksIn this paper, we have described a new global reanalysis (CFSR) produced at NCEPcovering the period 1979 to the present. Sections in this paper describe the observationaldatasets, forecast models and data assimilation systems used in this endeavor. We alsobriefly present some preliminary results. The accuracy of this new reanalysis is hard toassess directly, but using the 5-day forecast scores as a measure of the accuracy of initialstates, (a reasonable assumption), we conclude that CFSR is considerably more accurate- 54 -
than the previous global reanalysis made at NCEP in the 1990s. It is more comprehensive,since it includes analyses of both the ocean and sea ice, and it has higher resolution inspace and time. The accuracy increases over time, especially in the Southern Hemispherewhere the use of satellite radiance data becomes very important.Many known errors in the observational data ingest and execution of the previousreanalyses was corrected in the CFSR. Many of the input datasets have been improved byyears of quality control and by exposure to successive reanalyses at various centers, mostnotably at ECMWF, NCEP and JMA. Undoubtedly, some errors may still persist andmore errors may be discovered in the future, but this is all part of the converging processof maker better and better analyses of the Earth’s system. A thorough study is alsorequired of the benefits of coupling the atmosphere to the ocean and the sea ice, but atfirst blush, this aspect appears to have worked very well in the CFSR. TheSST/precipitation correlation has improved in the tropics. Some problems related toexecuting the project in many streams (as is common to speed up the process) still exist.All subcomponents with longer time scales (such as the deep soil, deep ocean and the topof the atmosphere) have discontinuities where one stream ends and the next one begins,this in spite of a full one year overlap between the streams.Future developments include the following three projects:1. CFSR was conducted mainly to create initial conditions for the coupledatmosphere-ocean-land-sea ice Reforecasts of the next Climate ForecastSystem, over the period 1982-present. This project is underway at NCEP. Thedesign of these reforecasts is as follows: From every fifth day in the calendar,there will be four 9-month ‘seasonal’ forecasts from 0, 6, 12 and 18UTC.From every day, there will also be shorter predictions, one run to the firstseason (105 days) at 0Z and three runs to 45 days from 6, 12 and 18 UTC. Theemphasis on the shorter subseasonal predictions, for the MJO and week 3-6forecasts, is to bridge the weather-climate gap and was the main reason for ahigh resolution reanalysis to be conducted. There is consensus that, given a- 55 -
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ABSTRACTThe NCEP Climate Forecast S
Page 4 and 5: 1. IntroductionThe first reanalysis
Page 6 and 7: In this paper we only discuss globa
Page 8 and 9: the reanalysis was halted to addres
Page 10 and 11: online archive of data for reanalys
Page 12 and 13: density MESONET data is included in
Page 14 and 15: The 1B datasets were calibrated usi
Page 16 and 17: MetOp is Europe's first polar-orbit
Page 20 and 21: The third GSI feature enabled in th
Page 22 and 23: the hydrostatic assumption. Soon af
Page 24 and 25: esolution with 28 sigma layers in t
Page 26 and 27: SW and LW radiations at one-hour in
Page 28 and 29: SST data. The other uses AVHRR and
Page 30 and 31: y Gent and McWilliams (1990; see al
Page 32 and 33: from the Global Temperature-Salinit
Page 34 and 35: through the end of the data set in
Page 36 and 37: The passive microwave weather filte
Page 39 and 40: from the sea ice/ocean back to the
Page 41 and 42: weight is assigned to the gauge ana
Page 43 and 44: Stream 6: 1 Jan 1994 to 31 Mar 1999
Page 45 and 46: in the mid 1990’s, the period whe
Page 47: e due to a change over the oceans (
Page 52 and 53: In Figure 49, we show the temporal
Page 56 and 57: forecast model at a lower resolutio
Page 58 and 59: Appendix A: AcronymsAER Atmospheric
Page 60 and 61: ONPCMDIPIRATAPROFLRQBOQuikSCATR1R2R
Page 62 and 63: TMP2M 2m air temperature 24 / 473TM
Page 64 and 65: Appendix C: The Data AccessTo addre
Page 66 and 67: Figure 26 shows the global total bi
Page 68 and 69: Argo Science Team, 2001: The global
Page 70 and 71: Compo, G.P., J.S. Whitaker, and P.D
Page 72 and 73: ozone Mapping and Profiler Suite (O
Page 75 and 76: Global Forecast System. Manuscript
Page 77 and 78: and climate models. Atmos. Chem. Ph
Page 79 and 80: performance Earth system modeling w
Page 81 and 82: with mesoscale numerical weather pr
Page 83 and 84: experiments using SSM/I wind speed
Page 85 and 86: Figure 21: Same as Figure 2, but fo
Page 87 and 88: Figure 45: The fit of 6-hour foreca
Page 89 and 90: Figure 1: Diagram illustrating CFSR
Page 91 and 92: Figure 3: Same as in Figure 2, but
Page 103 and 104: Figure 15: Radiance instruments on
Page 105 and 106:
Figure 17: Same as in Figure 16, bu
Page 107 and 108:
Figure 19: Global average Tb first
Page 109 and 110:
Figure 21: Same as in Figure 16, bu
Page 111:
Figure 23: Comparisons of the SSU b
Page 114 and 115:
Figure 26: The global total bias fo
Page 116 and 117:
Figure 28: The yearly total of trop
Page 118 and 119:
Figure 30: The vertical structure o
Page 120 and 121:
Figure 32: The global number of tem
Page 122 and 123:
Figure 34: The same as Figure 33, b
Page 124 and 125:
Figure 36: Monthly mean Sea ice ext
Page 126 and 127:
Figure 38: 2-meter volumetric soil
Page 128 and 129:
Figure 40: Schematic of the executi
Page 130 and 131:
Figure 42: Yearly averaged Southern
Page 132 and 133:
Figure 44: Monthly mean hourly surf
Page 134 and 135:
Figure 46: Global mean temperature
Page 136 and 137:
Figure 48: Zonal mean total ozone d
Page 138 and 139:
Figure 50: The subsurface temperatu
Page 140 and 141:
Figure 52: Vertical profiles of the
Page 142 and 143:
Figure 54: Zonal surface velocities
Page 144 and 145:
ProgramPREVENTSACQCACAR_CQCCQCCQCVA
Page 146:
Satellite Starting date Ending Date
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