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For 200 hPa zonal wind the largest uncertainties are in the tropical regions. | For 850 hPa temperature, the uncertainties are generally larger in the Southern Hemisphere (this corresponds well with the fact that we have fewer observations in the Southern Hemisphere). | For MSLP the Antarctic region has the largest spread/uncertainty. |
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For all variables it is clear that the uncertainties are decreasing with time, i.e. the spread values are smaller for recent periods than for older ones.
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