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from the Global Temperature-Salinity Profile Project (GTSPP) at:http://www.nodc.noaa.gov/GTSPPAn important aspect of the collection of temperature profiles that will have impact on anylong-term ocean reanalysis is the variability in the distribution of the profiles in time andspace over the last 30 years. Figure 32 illustrates, for the profiles used in this analysis,the number of temperature observations available per month as a function of depthbetween 1980 and the end of 2008. The stratification of colors reflects the penetrationdepths of different instrument types. The rapid growth of the Argo array after the year2000 dominates the latter part of the figure.There also have been significant changes in the geographical distribution of the profiles.Figure 33-34 which show two annual distributions of profiles (1985 and 2008) givessome idea of the scope of these changes. The year 1985 is dominated by XBTobservations collected along shipping routes and during research operations; only a fewearly TAO moorings have appeared in the tropical Pacific. As a result there are largedata voids nearly everywhere and the Southern Ocean is largely unobserved. By 2008 thetropical mooring arrays have expanded into all three ocean basins and the global pictureis dominated by Argo profiles. Some gaps remain and marginal seas are not sampled bythe Argo array, but there is a nearly complete global coverage.4.4.2 Salinity ProfilesPrior to the advent of the Argo array subsurface salinity observations were extremelysparse. For that reason we assimilate synthetic salinity profiles in the ocean analysis.Each synthetic profile is constructed from an observed temperature profile and the localclimatological T-S correlation based on the World Ocean Database 1998 (Conkright et al.,1999). An important advantage of this approach is that it maintains water massproperties over the course of the reanalysis. The disadvantage is that some salinityvariability in the near surface is lost.4.4.3 Surface Observations- 32 -
As indicated above, temperature and salinity in the top level of the model are relaxed togridded fields of observed sea surface temperature (SST) and sea surface salinity (SSS).The SST data are the daily fields described in section 4.1. The SSS data is aclimatological map based on the World Ocean Database 1998 (Conkright et al., 1999).The SST and SSS fields are remapped to the model grid before being used in the analysis.5. The Sea IceThe accuracy of sea ice coverage is essential for a good reanalysis of the atmosphereand ocean over the polar regions. Global climate modeling studies have shown that seaice concentrations strongly affect the climate in the Antarctic regions (e.g., Simmondsand Wu (1993)). However, sea ice concentrations were prescribed in the previous NCEPreanalysis (R1 and R2). The CFSR allows sea ice concentration to be predicted in theforecast guess which provides closer sea ice-atmosphere linkages in the data assimilationsystem. This should improve the description of the main climatic patterns and trends overthe polar regions in the CFSR.5.1 The Sea Ice Concentration AnalysisThe target in this analysis was to produce a global record of surface ice concentration forall points that may freeze anywhere on the globe, on a daily grid of 0.5 o latitudelongituderesolution throughout the period of the CFSR. Further, the aim was to producethe best analysis for the given day. This latter goal means that there are discontinuities inthe production of the data set, where newer data sets start to be used, and newer methodof analysis are used, or where, as for the Great Lakes, a high quality data set ended. Timeseries analyses are needed to take care of these discontinuities.From the start of the CFSR through 31 December 1996, the global ice concentrations formost of the globe are simply regridded from [Cavalieri, et al., 1996, updated 2007](GSFC Ice), except for a) possibly ice-covered regions that lie outside that grid, b) largeCanadian lakes, c) the Great Lakes and d) SST-based filtering of erroneous ice in theanalysis.For the Great Lakes, the data used are Assel et al. [2002] from the start of the CFSR- 33 -
Page 2 and 3: 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 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 54 and 55: distributed in time and space. Desp
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
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Figure 3: Same as in Figure 2, but
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Page 95 and 96:
Page 97 and 98:
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Page 103 and 104:
Figure 15: Radiance instruments on
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Figure 17: Same as in Figure 16, bu
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Figure 19: Global average Tb first
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Figure 21: Same as in Figure 16, bu
Page 111:
Figure 23: Comparisons of the SSU b
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Figure 26: The global total bias fo
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Figure 28: The yearly total of trop
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Figure 30: The vertical structure o
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Figure 32: The global number of tem
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Figure 34: The same as Figure 33, b
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Figure 36: Monthly mean Sea ice ext
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Figure 38: 2-meter volumetric soil
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Figure 40: Schematic of the executi
Page 130 and 131:
Figure 42: Yearly averaged Southern
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Figure 44: Monthly mean hourly surf
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Figure 46: Global mean temperature
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Figure 48: Zonal mean total ozone d
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Figure 50: The subsurface temperatu
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Figure 52: Vertical profiles of the
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Figure 54: Zonal surface velocities
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ProgramPREVENTSACQCACAR_CQCCQCCQCVA
Page 146:
Satellite Starting date Ending Date
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