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In Figure 49, we show the temporal lag-correlation coefficient between precipitation andSST in the tropical Western Pacific region in two generations of NCEP reanalysis data. Datafor the boreal winter (Nov-Apr) over the period 1979-2008 are band-pass filtered for 20-100days after removing the climatological mean.It shows clearly that the precipitation-SST relationship in CFSR is consistent withobservational data: At lag 0, precipitation has a weak negative correlation with SST. Thepositive correlation of SST and precipitation gradually increases with a warming of theSST (negative lags on the horizontal axis in the figure), reaching a maximum at lag day -7. On the other hand, the cooling of SST by precipitation reaches a maximum at lag day 5(positive lags on the horizontal axis in the figure). In R1 and R2, the increase inprecipitation due to warming of the SST is too quick, which implies a lack of coupling inthe data-assimilation system or a problem with using an observed SST which was aweekly-averaged product. In the coupled CFSR, this deficiency is largely corrected.These results are consistent with the observational study of Woolnough et al. (2000) andthe coupled vs uncoupled model comparison studies of Pegion and Kirtman (2008); andFu and Wang (2004).10.2 The Oceanic ComponentIn this subsection, we present a few results from the oceanic component of the CFSR, andcompare them to observations.Equatorial cross-sections of temperature are shown in Figure 50 for the CFSR (top) forthe years 1982-2008 and for observations from the World Ocean Atlas (WOA) (bottom)obtained from Conkright et al. (1999). The 20 o C isotherm, which, at the equator, is closeto the maximum vertical temperature gradient (plotted as a black line) slopes upwardtoward the east, from a depth of approximately 150 m in the western equatorial PacificOcean to approximately 20m depth in the equatorial cold tongue region. While the depthsof the 20 o C isotherms in the two sections are in good agreement, the thermocline in the- 52 -
CFSR is more diffuse, such that that CFSR section is cooler than the WOA section abovethe 20 o C and warmer below.The corresponding equatorial cross-section of the zonal velocity in the CFSR is shown inFigure 51. The isopleths slope upward toward the east in the equatorial Atlantic, Pacificand Indian Oceans. The core of the undercurrent is approximately centered on the 20 o Cisotherm and the maximum mean velocity is about 0.85m/s at 130 o W in the equatorialPacific.The equatorial temperatures and zonal velocites are also compared with the TAOmooring data in Figure 52. Vertical profiles of the subsurface temperature (top panels)and zonal velocities (bottom panels) are shown for four locations in the equatorial PacificOcean for the CFSR (red line) and for the TAO observations (black line). The CFSRtemperature profiles are very close to the TAO observations. This is an expected resultsince TAO observations are assimilated by the CFSR. One noticeable difference is thatthe CFSR temperatures are approximately 1 o C colder than the TAO temperatures belowthe thermocline in the western equatorial Pacific. The core depth of the undercurrent inthe CFSR is in good agreement with the TAO observations in the eastern part of the basin,although the magnitude of the undercurrent in the CFSR is about 10-15% less thanobserved. The CFSR also has difficulty capturing the mean westward flow in the centralbasin that is seen the TAO data.The vertically averaged temperature is plotted in Figure 53 for CFSR for the years: 1979-2008, and for observations from the World Ocean Atlas (Conkright et al., 1999). Notethat the plots show remarkable agreement, with the main difference being that the CFSRis approximately 0.5C colder than the observations between 30S-30N.In Figure 54, zonal and meridional velocities from the first level (5m) of the CFSR arecompared with the same fields derived from surface drifters drogued at 15m (Lumpkinand Pazos, 2006). In making this comparison it should be kept in mind that the CFSRmaps were made from averages of Eulerian velocities on the model grid, while the driftermaps were constructed from pseudo-Lagrangian motion of drifters non-uniformly- 53 -
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 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 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
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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