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Colouring on the charts is implies >90% significance for the anomaly from ER-M-ClimatClimate.  White shading on the maps only implies <90% significance of the anomaly.  It does not necessarily imply:point to a forecast of average nor to a 'don't know' forecast of climatology.

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Further information can be gained by inspection of the Extended anomaly meteogram.  Click the mouse over any location on the ensemble charts to produce probability information in meteogram diagrammatic formform. 

The example (Fig8.2.3-1) shows white shading on the maps.  When presented with white shading at the location of interest, the user should inspect the anomaly Meteograms and CDFs to decide the likely anomaly and assess the confidence.

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Fig8.2.3-1:  Consider T2m temperature forecast anomalies from model climate at the location in southern Sweden (shown at X).

For week 1, the meteogram shows a high confidence forecast of low anomalies (box and whisker symbol quite short centred near 0ºC) implying near-normal mean 2m temperatures.  This is confirmed by the relatively vertical red CDF profile near the 0ºC anomaly line.

For week 5, the meteogram shows much less certainty in the anomalies (box and whisker symbol fairly extended) implying a larger spread of mean 2m temperature anomalies and mean 2m temperatures.  The CDF profile suggests the forecast is much like climatology as the red line of the forecast anomalies is almost coincident with the black line of the model climate distribution of anomalies.  Forecast and climatology are equally uncertain.

In both cases in this example there is white shading on the maps at location X. The example shows white shading on the maps cannot, of itself, point to a forecast of average (as at week 1) nor to a 'don't know' forecast of climatology (as at week 5).

Probability that weekly mean anomaly from model climate greater than zero

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