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• The vertical structure of temperature (red) and moisture (dewpoint, green) in tephigram format, and also dewpoint depression (blue).  Shaded bands denote for the ensemble the minimum, 25th and 75th percentiles and maximum for each of temperature, dewpoint and dewpoint depression distributions at each level, with the median value shown by a thin solid line.  This display strategy mirrors the use of box-and-whisker plots on meteograms.  A thick solid line represents Ensemble Control Forecast (ex-HRES) (as on meteogram products).
  
  • Dewpoint depressions are first computed from each ensemble member output at each level, and then the spread and median are derived in the same way as for temperatures and dewpoint.  So maximum dewpoint depression shown is not derived from the highest temperature on any ensemble member and the lowest dewpoint on any ensemble member at that level.
  • Wind arrows from Ensemble Control Forecast (ex-HRES) standard level output are shown on the dewpoint depression diagram (5m/s per full barb).  This plotting position was chosen for convenience, and not because of any direct or implied relationship with the dewpoint depression information itself.
  • Note that whilst the Ensemble Control Forecast (ex-HRES) traces for each thermal variable all represent plausible solutions, the same cannot be said for the median traces because they will very probably comprise data from different runs at different levels.

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Fig8.1.8-2: An example of ecCharts vertical profile output.  Note: The diagram is output from Cy48r when the resolution of HRES (~9km) differed from the resolution of medium range ensemble (~18km) and so HRES and Ensemble Control Forecast differ.  With effect from Cy49r1, HRES and Ensemble Control Forecast (ex-HRES) are scientifically, structurally and computationally identical and their results are a single trace on the vertical profile.

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